HRV · desk opened JUL 9 2026 · revision 8
Reviewed OCT 24 2026
HRV: What Holds Up and What Doesn't
Alcohol, training, stress and illness all move heart rate variability. Each claim here is sorted into what is solid, what is shaky, and what does not hold up.
32 questions rated against 209 screened studies. Each rating is the evidence on that one question, not an average of the desk.
HRV hub →Where the evidence stands · 32 questions rated the number beside each is how many studies sit behind it
Established
9 questions
- Does heart rate variability reflect autonomic function and predict health outcomes?62
- Is there a normal HRV range, and does it change with age?10
- Does alcohol lower HRV?5
- Does regular exercise increase HRV?7
- Is a chest strap as accurate as an ECG for HRV?5
- Does HRV still mean anything in atrial fibrillation or heart failure?4
- Can a wearable detect seizures from HRV?3
- Does Ozempic raise your heart rate?5
- Is the Oura Ring's HRV accurate compared with an ECG?5
Emerging
13 questions
- Does a sudden drop in HRV reflect a real physiological change?5
- Does HRV biofeedback reduce substance-use cravings?2
- Is lower HRV associated with depression?11
- Is lower HRV associated with anxiety?6
- Does cannabis affect HRV?1
- Does air pollution exposure lower HRV?1
- Is a short HRV reading reliable?4
- Can a wearable predict PTSD after trauma?5
- Does work stress lower your HRV?6
- Is HRV lower in bipolar disorder?2
- Does an ice bath after exercise improve HRV recovery?1
- Can heart rate variability detect sleep apnea?7
- Does HRV reflect mental workload?6
Uncertain
8 questions
- Do consumer wearables measure HRV accurately compared to an ECG reference?30
- Is trait neuroticism associated with lower heart rate variability?8
- Does HRV biofeedback reduce anxiety?8
- Do slow-breathing exercises increase HRV?5
- Do antidepressants change HRV?2
- Does HRV vary across the menstrual cycle?3
- Does higher HRV mean better self-control?1
- How accurate is Apple Watch HRV compared with medical devices?4
Unsupported
2 questions
Does heart rate variability reflect autonomic function and predict health outcomes?
§Rated proposition Lower heart rate variability is associated with worse cardiovascular and autonomic health outcomes.
What the studies found Higher heart rate variability reflects better autonomic function and recovery, and lower HRV is associated with worse health outcomes.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
What would change this rating
- A new core-hitting conflicting study, a retraction of an anchor, or a failed replication would lower this rating.
Used in 15 articles
- Low HRV But You Feel Fine? The Number May Be the Device, Not You2 shared studies
- Does Your Bedroom Temperature Affect Your HRV at Night?1 shared study
- Higher HRV Tracks a Flexible Stress Response, Not Immunity1 shared study
- Does HRV Reflect Depression?2 shared studies
- Does HRV Actually Mean Anything If You Have Heart Failure or AFib?2 shared studies
- HRV and Anxiety: Two Different Questions, Not One2 shared studies
- Paced Breathing at Resonance Frequency Raised HRV in Trials1 shared study
- What Is a Good HRV for a 40 Year Old?1 shared study
- What Is a Good HRV for a 50 Year Old?1 shared study
- What Is a Good HRV for a 60 Year Old?1 shared study
- HRV Biofeedback Went With Less Substance Use in One Trial1 shared study
- Does Low HRV Actually Predict Who Becomes Aggressive?1 shared study
- Can Your Wearable's HRV Predict PTSD After Trauma?1 shared study
- Why Your HRV Keeps Dropping, and When the Night Explains It1 shared study
- What Is a Good HRV? The Number Means Less Than You Think1 shared study
62 studies scored · 7 anchor · 48 supporting · 2 null-result · 5 commentary (not counted) · Evidence last evaluated Oct 24, 2026
Do consumer wearables measure HRV accurately compared to an ECG reference?
§Rated proposition Consumer wearable devices measure HRV with sufficient agreement to a validated reference to be meaningful.
KnowYourPrime Evidence RegistryFinding KYP-ER-0003, the permanent, citable record of this rating
What the studies found Consumer wearables measure HRV accurately enough to be meaningful for everyday users.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
- An anchor study is present but its own reported finding does not cleanly affirm this claim, so it does not count toward the Established threshold.
- A clean anchor supports this claim, but an unresolved conflicting study contradicts it on the core relationship, so the evidence is treated as in genuine dispute.
- Some evidence conflicts on secondary points that do not change the core direction.
Used in 16 articles
- What Is a Good HRV? The Number Means Less Than You Think6 shared studies
- Chest Strap HRV Accuracy vs ECG4 shared studies
- How Does HRV Work? ECG vs PPG Sensing on Wearables3 shared studies
- Why Your HRV Keeps Dropping, and When the Night Explains It3 shared studies
- How Accurate Is Your Wearable's PPG-Based HRV Compared to a Clinical ECG?1 shared study
- Apple Watch Nails Resting Heart Rate and Misses on HRV4 shared studies
- What Is a Good HRV for a 40 Year Old?2 shared studies
- Does Your Bedroom Temperature Affect Your HRV at Night?1 shared study
- Paced Breathing at Resonance Frequency Raised HRV in Trials1 shared study
- Is a Cheap Heart Rate Strap As Accurate As a Polar H10 for Tracking HRV?1 shared study
- Does HRV Reflect Depression?1 shared study
- What Is a Good HRV for a 50 Year Old?1 shared study
- What Is a Good HRV for a 60 Year Old?1 shared study
- What Is a Good HRV for a 70 Year Old?1 shared study
- Does HRV Actually Mean Anything If You Have Heart Failure or AFib?1 shared study
- Low HRV But You Feel Fine? The Number May Be the Device, Not You1 shared study
30 studies scored · 7 anchor · 20 supporting · 3 conflicting · Evidence last evaluated Oct 24, 2026
Is trait neuroticism associated with lower heart rate variability?
§Rated proposition Higher trait neuroticism is associated with lower resting heart rate variability.
What the studies found Higher trait neuroticism is associated with lower heart rate variability.
- Anchor-grade evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
- An anchor study is present but its own reported finding does not cleanly affirm this claim, so it does not count toward the Established threshold.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
- Null-result evidence bears directly on the claimed effect.
Used in 4 articles
- HRV and Anxiety: Two Different Questions, Not One7 shared studies
- What Is a Good HRV for a 40 Year Old?1 shared study
- What Is a Good HRV for a 50 Year Old?1 shared study
- HRV Biofeedback Went With Less Substance Use in One Trial1 shared study
8 studies scored · 2 anchor · 5 supporting · 1 null-result · Evidence last evaluated Oct 24, 2026
Is there a normal HRV range, and does it change with age?
§Rated proposition Resting heart rate variability declines with age in healthy people.
KnowYourPrime Evidence RegistryFinding KYP-ER-0014, the permanent, citable record of this rating
What the studies found Resting heart rate variability declines steadily with age, so what counts as a normal value depends on age.
- Anchor-grade evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
- Some evidence conflicts on secondary points that do not change the core direction.
What would change this rating
- A new core-hitting conflicting study, a retraction of an anchor, or a failed replication would lower this rating.
Used in 4 articles
- What Is a Good HRV for a 40 Year Old?2 shared studies
- What Is a Good HRV for a 60 Year Old?1 shared study
- Does HRV Actually Mean Anything If You Have Heart Failure or AFib?1 shared study
- Why Your HRV Keeps Dropping, and When the Night Explains It1 shared study
10 studies scored · 5 anchor · 3 supporting · 2 conflicting · Evidence last evaluated Oct 24, 2026
Does a sudden drop in HRV reflect a real physiological change?
§Rated proposition A fall in overnight heart rate variability precedes the onset of an acute infection.
KnowYourPrime Evidence RegistryFinding KYP-ER-0013, the permanent, citable record of this rating
What the studies found A sudden fall in overnight HRV can precede the symptoms of an acute infection by a day or two.
- Anchor-grade evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
Used in 3 articles
5 studies scored · 1 anchor · 4 supporting · Evidence last evaluated Oct 24, 2026
Does alcohol lower HRV?
§Rated proposition Acute alcohol consumption lowers heart rate variability.
What the studies found Alcohol lowers heart rate variability during and after drinking, and the effect scales with how much is consumed.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
What would change this rating
- A new core-hitting conflicting study, a retraction of an anchor, or a failed replication would lower this rating.
Used in 3 articles
- How Long Does Alcohol Lower HRV?4 shared studies
- HRV Biofeedback Went With Less Substance Use in One Trial1 shared study
- Why Your HRV Keeps Dropping, and When the Night Explains It1 shared study
5 studies scored · 2 anchor · 3 supporting · Evidence last evaluated Oct 24, 2026
Does regular exercise increase HRV?
§Rated proposition Regular exercise training increases heart rate variability.
What the studies found Regular exercise training raises heart rate variability, with most of the trial evidence coming from people who have a cardiovascular condition.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
What would change this rating
- A new core-hitting conflicting study, a retraction of an anchor, or a failed replication would lower this rating.
Used in 1 article
- How Often You Train Decides Whether HRV Improves4 shared studies
7 studies scored · 3 anchor · 3 supporting · 1 null-result · Evidence last evaluated Oct 24, 2026
Does HRV biofeedback reduce anxiety?
§Rated proposition Heart rate variability biofeedback reduces anxiety.
What the studies found HRV biofeedback is followed by large drops in self-reported anxiety, but the controlled trials that compare it against a sham do not find an advantage over the sham.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
- An anchor study is present but its own reported finding does not cleanly affirm this claim, so it does not count toward the Established threshold.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
- Null-result evidence bears directly on the claimed effect.
Used in 2 articles
- Does HRV Biofeedback Actually Reduce Anxiety?6 shared studies
- Paced Breathing at Resonance Frequency Raised HRV in Trials1 shared study
8 studies scored · 2 anchor · 4 supporting · 2 null-result · Evidence last evaluated Oct 24, 2026
Do slow-breathing exercises increase HRV?
§Rated proposition Slow-paced breathing raises heart rate variability more than breathing at a normal rate.
What the studies found Four weeks of resonance breathing training raised HRV in a controlled trial, but the largest direct comparison found slow breathing no better than normal breathing for HRV in the moment.
- Anchor-grade evidence affirms the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
- Null-result evidence bears directly on the claimed effect.
- Some evidence conflicts on secondary points that do not change the core direction.
Used in 1 article
- Paced Breathing at Resonance Frequency Raised HRV in Trials3 shared studies
5 studies scored · 1 anchor · 2 supporting · 1 conflicting · 1 null-result · Evidence last evaluated Oct 24, 2026
Does HRV biofeedback reduce substance-use cravings?
§Rated proposition Heart rate variability biofeedback reduces craving in substance use disorder.
What the studies found HRV biofeedback added to usual treatment reduced craving in a randomized trial in substance use disorder, where craving rose in the control group.
- Anchor-grade evidence affirms the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
Used in 1 article
- HRV Biofeedback Went With Less Substance Use in One Trial2 shared studies
2 studies scored · 1 anchor · 1 supporting · Evidence last evaluated Oct 24, 2026
Is lower HRV associated with depression?
§Rated proposition People with major depression have lower resting heart rate variability.
What the studies found People with major depression have lower resting HRV, but the same is true across most of psychiatry, so a low reading is not a sign of depression specifically.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
- Null-result evidence bears directly on the claimed effect.
- Some evidence conflicts on secondary points that do not change the core direction.
Used in 2 articles
- Does HRV Reflect Depression?9 shared studies
- HRV and Anxiety: Two Different Questions, Not One1 shared study
11 studies scored · 3 anchor · 6 supporting · 1 conflicting · 1 null-result · Evidence last evaluated Oct 24, 2026
Is lower HRV associated with anxiety?
§Rated proposition People with an anxiety disorder have lower resting heart rate variability.
What the studies found Resting HRV is lower in generalized anxiety and panic disorder, but not in social anxiety or obsessive-compulsive disorder, so the association is not uniform across anxiety conditions.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- An anchor study is present but its own reported finding does not cleanly affirm this claim, so it does not count toward the Established threshold.
- Null-result evidence bears directly on the claimed effect.
Used in 2 articles
- HRV and Anxiety: Two Different Questions, Not One3 shared studies
- Does HRV Reflect Depression?1 shared study
6 studies scored · 3 anchor · 2 supporting · 1 null-result · Evidence last evaluated Oct 24, 2026
Do antidepressants change HRV?
§Rated proposition Antidepressant treatment lowers heart rate variability.
What the studies found A controlled trial of venlafaxine and mirtazapine found HRV fell further during treatment, while a larger comparison across antidepressant classes found no significant drug effect.
- Anchor-grade evidence affirms the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
- Null-result evidence bears directly on the claimed effect.
Used in 1 article
- Depression Lowers HRV, and Antidepressants Act Differently2 shared studies
2 studies scored · 1 anchor · 1 null-result · Evidence last evaluated Oct 24, 2026
Does low HRV predict reactive aggression?
§Rated proposition Lower heart rate variability predicts reactive aggression.
What the studies found HRV does not predict reactive aggression. A meta-analysis of 48 effect estimates found no correlation, against a theory that predicted one.
- Null-result evidence bears directly on the claimed effect.
Used in 1 article
- Does Low HRV Actually Predict Who Becomes Aggressive?1 shared study
1 studies scored · 1 null-result · Evidence last evaluated Oct 24, 2026
Does cannabis affect HRV?
§Rated proposition Acute THC lowers heart rate variability.
What the studies found Oral THC lowers heart rate variability and raises heart rate, and the size of the drop tracks the dose.
- Anchor-grade evidence affirms the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
Used in 1 article
1 studies scored · 1 anchor · Evidence last evaluated Oct 24, 2026
Does air pollution exposure lower HRV?
§Rated proposition Higher indoor fine-particulate exposure lowers heart rate variability.
What the studies found Cutting indoor fine-particulate exposure raised HRV within a single working day in a randomized crossover trial.
- Anchor-grade evidence affirms the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
Used in 1 article
1 studies scored · 1 anchor · Evidence last evaluated Oct 24, 2026
Does HRV vary across the menstrual cycle?
§Rated proposition Heart rate variability follows a consistent pattern across the menstrual cycle.
What the studies found A large wearable study found HRV falls before menses and rises after, while a densely sampled study aligned to ovulation found no consistent population-level rhythm at all.
- Anchor-grade evidence affirms the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
- Null-result evidence bears directly on the claimed effect.
- Some evidence conflicts on secondary points that do not change the core direction.
Used in 2 articles
- What Your HRV and Resting Heart Rate Actually Do Across a Cycle3 shared studies
- Why Your HRV Keeps Dropping, and When the Night Explains It2 shared studies
3 studies scored · 1 anchor · 1 conflicting · 1 null-result · Evidence last evaluated Oct 24, 2026
Do beta blockers lower HRV?
§Rated proposition Beta blockers lower heart rate variability.
What the studies found Beta blockers cut heart rate sharply and leave HRV unchanged. In one randomized trial atenolol raised it.
- At least one unresolved conflicting study bears on the core claim, capping the rating until reconciled.
- Null-result evidence bears directly on the claimed effect.
Used in 1 article
3 studies scored · 1 conflicting · 2 null-result · Evidence last evaluated Oct 24, 2026
Is a chest strap as accurate as an ECG for HRV?
§Rated proposition A chest-strap heart rate monitor agrees with ECG for HRV at rest.
KnowYourPrime Evidence RegistryFinding KYP-ER-0004, the permanent, citable record of this rating
What the studies found A chest strap matches a clinical ECG for HRV at rest, closely enough to be interchangeable with it. Agreement falls away as exercise intensity rises.
- Anchor-grade evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
What would change this rating
- A new core-hitting conflicting study, a retraction of an anchor, or a failed replication would lower this rating.
Used in 5 articles
- Is a Cheap Heart Rate Strap As Accurate As a Polar H10 for Tracking HRV?2 shared studies
- Chest Strap HRV Accuracy vs ECG3 shared studies
- Apple Watch Nails Resting Heart Rate and Misses on HRV1 shared study
- How Does HRV Work? ECG vs PPG Sensing on Wearables1 shared study
- What Is a Good HRV? The Number Means Less Than You Think1 shared study
5 studies scored · 2 anchor · 3 supporting · Evidence last evaluated Oct 24, 2026
Is a short HRV reading reliable?
§Rated proposition A heart rate variability recording shorter than five minutes gives a reliable RMSSD.
What the studies found RMSSD stays reliable in recordings as short as one minute. The other HRV indices need longer.
- Anchor-grade evidence affirms the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
- Some evidence conflicts on secondary points that do not change the core direction.
Used in 1 article
- How Long Does an HRV Check Actually Need to Be?3 shared studies
4 studies scored · 1 anchor · 2 supporting · 1 conflicting · Evidence last evaluated Oct 24, 2026
Does HRV still mean anything in atrial fibrillation or heart failure?
§Rated proposition Low heart rate variability predicts mortality in people with heart failure.
What the studies found Low HRV independently predicts mortality in heart failure and after a myocardial infarction, which is not true of the general population.
- Systematic-review or meta-analytic evidence affirms the core relationship.
What would change this rating
- A new core-hitting conflicting study, a retraction of an anchor, or a failed replication would lower this rating.
Used in 1 article
4 studies scored · 2 anchor · 2 supporting · Evidence last evaluated Oct 24, 2026
Can a wearable predict PTSD after trauma?
§Rated proposition Wrist-wearable heart rate variability identifies posttraumatic neuropsychiatric symptoms after trauma exposure.
What the studies found Wrist-wearable HRV features track posttraumatic symptoms in the months after a traumatic event, both at a point in time and as symptoms change.
- Anchor-grade evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
Used in 1 article
- Can Your Wearable's HRV Predict PTSD After Trauma?3 shared studies
5 studies scored · 1 anchor · 4 supporting · Evidence last evaluated Oct 24, 2026
Can a wearable detect seizures from HRV?
§Rated proposition An HRV algorithm on a wearable ECG detects seizures in patients with marked ictal autonomic change.
What the studies found In the roughly half of patients whose seizures produce a marked heart rate change, an HRV algorithm on a wearable ECG detects them, including seizures without convulsions, at about one false alarm a day.
- Anchor-grade evidence affirms the core relationship.
What would change this rating
- A new core-hitting conflicting study, a retraction of an anchor, or a failed replication would lower this rating.
Used in 2 articles
- Can a Wearable Detect Seizures?2 shared studies
- Why Your HRV Keeps Dropping, and When the Night Explains It1 shared study
3 studies scored · 2 anchor · 1 supporting · Evidence last evaluated Oct 24, 2026
Does work stress lower your HRV?
§Rated proposition Higher occupational stress is associated with lower heart rate variability.
KnowYourPrime Evidence RegistryFinding KYP-ER-0006, the permanent, citable record of this rating
What the studies found Workers reporting higher occupational stress show lower heart rate variability, mainly as reduced parasympathetic activity, though the one study that tested it within teachers across a working day found no such effect on state HRV.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
- Null-result evidence bears directly on the claimed effect.
Used in 2 articles
- Why Your HRV Keeps Dropping, and When the Night Explains It1 shared study
- What Is a Good HRV? The Number Means Less Than You Think1 shared study
6 studies scored · 2 anchor · 3 supporting · 1 null-result · Evidence last evaluated Oct 24, 2026
Is HRV lower in bipolar disorder?
§Rated proposition People with bipolar disorder have lower resting heart rate variability.
What the studies found People with bipolar disorder have lower resting heart rate variability than people without it, though the pooled difference shrinks in the larger and better-conducted studies.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
Used in 1 article
- Does HRV Reflect Depression?1 shared study
2 studies scored · 1 anchor · 1 supporting · Evidence last evaluated Oct 24, 2026
Does an ice bath after exercise improve HRV recovery?
§Rated proposition Cold water immersion after exercise accelerates parasympathetic reactivation as measured by heart rate variability.
What the studies found Cold water immersion after hard exercise speeds the return of parasympathetic activity, measured as a rise in heart rate variability, compared with resting passively.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
1 studies scored · 1 anchor · Evidence last evaluated Oct 24, 2026
Can heart rate variability detect sleep apnea?
§Rated proposition Heart rate variability analysis detects obstructive sleep apnea accurately enough to screen for it.
What the studies found Analysis of heart rate variability detects obstructive sleep apnea at about 79 percent sensitivity and 75 percent specificity, which is screening accuracy rather than diagnostic accuracy, and it has been tested on ECG recordings rather than on a wrist wearable.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
- The claim rests on a single anchor whose finding affirms it; a second independent affirming anchor is needed to reach Established.
7 studies scored · 1 anchor · 6 supporting · Evidence last evaluated Oct 24, 2026
Does HRV reflect mental workload?
§Rated proposition Heart rate variability changes measurably in response to cognitive workload.
What the studies found Heart rate variability tracks mental workload in some studies and not others: a meta-analysis found it sensitive to task load, but a well-powered test of task difficulty found the effect in other cardiac measures while heart rate variability itself did not move.
- Systematic-review or meta-analytic evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
- Null-result evidence bears directly on the claimed effect.
6 studies scored · 2 anchor · 3 supporting · 1 null-result · Evidence last evaluated Oct 24, 2026
Does higher HRV mean better self-control?
§Rated proposition Higher resting heart rate variability is associated with better self-control.
What the studies found Resting heart rate variability is associated with performance on laboratory self-control tasks, but the pooled correlation is small at r = 0.15 and the meta-analysis that produced it found evidence of publication bias in the literature behind it.
- An anchor study was assessed but its own reported finding does not cleanly affirm this claim, so the evidence is treated as unsettled rather than affirming.
1 studies scored · 1 anchor · Evidence last evaluated Oct 24, 2026
Does Ozempic raise your heart rate?
§Rated proposition GLP-1 receptor agonists raise resting heart rate and lower heart rate variability.
What the studies found GLP-1 drugs raise resting heart rate by about 6.6 to 8.1 beats per minute and lower heart rate variability, and they do it despite the weight loss and metabolic improvement happening at the same time. Both randomized trials behind that were run in people with type 2 diabetes, one of them with coronary artery disease, not in otherwise healthy people taking these drugs to lose weight.
- Anchor-grade evidence affirms the core relationship.
- Multiple supporting studies are consistent with the core relationship.
What would change this rating
- A new core-hitting conflicting study, a retraction of an anchor, or a failed replication would lower this rating.
Used in 1 article
5 studies scored · 2 anchor · 3 supporting · Evidence last evaluated Oct 24, 2026
Is the Oura Ring's HRV accurate compared with an ECG?
§Rated proposition The Oura Ring measures overnight heart rate variability in close agreement with an ECG reference.
KnowYourPrime Evidence RegistryFinding KYP-ER-0024, the permanent, citable record of this rating
What the studies found In healthy adults, the Oura Ring's overnight HRV agrees closely with a simultaneous ECG, in independent and company-affiliated studies alike, though short 5-minute readings are noisier than night averages and errors are larger in people aged 45 and older.
- Anchor-grade evidence affirms the core relationship.
What would change this rating
- A new core-hitting conflicting study, a retraction of an anchor, or a failed replication would lower this rating.
Used in 4 articles
- What Is a Good HRV for a 40 Year Old?1 shared study
- What Is a Good HRV for a 50 Year Old?1 shared study
- What Is a Good HRV for a 60 Year Old?1 shared study
- What Is a Good HRV for a 70 Year Old?1 shared study
5 studies scored · 4 anchor · 1 supporting · Evidence last evaluated Oct 24, 2026
How accurate is Apple Watch HRV compared with medical devices?
§Rated proposition Apple Watch measures heart rate variability in close agreement with an ECG or chest-strap reference.
KnowYourPrime Evidence RegistryFinding KYP-ER-0025, the permanent, citable record of this rating
What the studies found Apple Watch heart rate and beat-to-beat intervals agree closely with ECG at rest, but its HRV figures agree less well: in the newest models tested, HRV ran consistently low and fell outside equivalence with a chest strap.
- An anchor study was assessed but its own reported finding runs contrary to this claim, so the evidence is treated as unsettled rather than affirming.
- An anchor study was assessed but its own reported finding supports this claim only weakly, so the evidence is treated as unsettled rather than affirming.
Used in 2 articles
- Apple Watch Nails Resting Heart Rate and Misses on HRV2 shared studies
- Chest Strap HRV Accuracy vs ECG1 shared study
4 studies scored · 2 anchor · 2 supporting · Evidence last evaluated Oct 24, 2026
MAINTAINED BY
The KnowYourPrime Research Desk · reviewed against new evidence on a rolling basis
Evidence on: Lower heart rate variability is associated with worse cardiovascular and autonomic health outcomes.
62 scored
Anchor Studies7
Heart Rate Variability and Risk of All-Cause Death and Cardiovascular Events in Patients With Cardiovascular Disease: A Meta-Analysis of Cohort Studies.
Journal
Biological research for nursing · 2020
PMID
31558032
RCR
16.3
Citations
213
Study type
Meta-analysis
Sample size
n = 28
cardiovascular diseasescause of death
The relationship of autonomic imbalance, heart rate variability and cardiovascular disease risk factors.
Journal
International journal of cardiology · 2010
PMID
19910061
RCR
56.2
Citations
1,577
Study type
Review
age factorsautonomic nervous system
Fractal analysis of heart rate variability as a predictor of mortality: A systematic review and meta-analysis.
Journal
Chaos (Woodbury, N.Y.) · 2018
PMID
30070502
RCR
2.6
Citations
41
Study type
Meta-analysis
cardiovascular diseasesfractals
Determinants of heart rate variability.
Journal
Journal of the American College of Cardiology · 1996
PMID
8917269
RCR
9.9
Citations
258
Study type
Primary study
adultelectrocardiography, ambulatory
Determinants of heart rate variability in the general population: The Lifelines Cohort Study.
Journal
Heart rhythm · 2019
PMID
29753022
RCR
3.8
Citations
62
Study type
Primary study
Sample size
n = 149,205
adolescentadult
Differential associations of resting heart rate and heart rate variability indices with cardiovascular and coronary heart disease mortality risk: the prospective KORA study.
Journal
Scientific reports · 2026
PMID
42618690
Citations
0
Study type
Primary study
Sample size
1390 adults
humansheart rate
Altered heart rate variability is associated with all-cause mortality in patients with co-morbid insomnia and obstructive sleep apnea.
Journal
Sleep · 2026
PMID
42315121
Citations
0
Study type
Primary study
Sample size
5225 participants
humanssleep apnea, obstructive
Supporting Studies48
Heart rate variability as predictive factor for sudden cardiac death.
Journal
Aging · 2019
PMID
29476045
RCR
11.8
Citations
202
Study type
Review
asymptomatic diseasesdeath, sudden, cardiac
Heart rate variability: a review.
Journal
Medical & biological engineering & computing · 2007
PMID
17111118
RCR
47.1
Citations
1,356
Study type
Review
alcohol drinkingarrhythmias, cardiac
Heart rate variability today.
Journal
Progress in cardiovascular diseases · 2013
PMID
23217437
RCR
12.7
Citations
305
Study type
Review
autonomic nervous systemcardiac resynchronization therapy
Heart rate variability.
Journal
Handbook of clinical neurology · 2014
PMID
24095141
RCR
10.0
Citations
221
Study type
Review
animalsautonomic nervous system
Heart rate variability in health and disease.
Journal
Scandinavian journal of work, environment & health · 1995
PMID
7618063
RCR
4.5
Citations
105
Study type
Review
arrhythmias, cardiaccircadian rhythm
Heart rate variability. Frequency domain analysis.
Journal
Cardiology clinics · 1992
PMID
1504981
RCR
7.3
Citations
164
Study type
Review
agingautonomic nervous system diseases
Heart rate variability and autonomic activity at rest and during exercise in various physiological conditions.
Journal
European journal of applied physiology · 2004
PMID
13680241
RCR
9.4
Citations
279
Study type
Review
altitudeautonomic nervous system
Interaction between heart rate and heart rate variability.
Journal
Annals of noninvasive electrocardiology : the official journal of the International Society for Holter and Noninvasive Electrocardiology, Inc · 2014
PMID
24602150
RCR
7.3
Citations
148
Study type
Review
autonomic nervous systemcardiovascular diseases
Resting Heart Rate Variability Measured by Consumer Wearables and Its Associations with Diverse Health Domains in Five Longitudinal Studies.
Journal
Sensors (Basel, Switzerland) · 2025
PMID
41374522
Citations
1
Study type
Primary study
humansheart rate
Associations Between Daily Heart Rate Variability and Self-Reported Wellness: A 14-Day Observational Study in Healthy Adults.
Journal
Sensors (Basel, Switzerland) · 2025
PMID
40732543
RCR
2.0
Citations
5
Study type
Observational study
Sample size
41 participants
humansheart rate
Heart rate variability coefficient of variation during sleep as a digital biomarker that reflects behavior and varies by age and sex.
Journal
American journal of physiology. Heart and circulatory physiology · 2026
PMID
41309064
Citations
3
Study type
Primary study
Sample size
21,000 individuals
humansmale
Heart rate variability over the decades: a scoping review.
Journal
PeerJ · 2025
PMID
40321810
RCR
5.3
Citations
14
Study type
Review
humansheart rate
Heart Rate Variability Applications in Medical Specialties: A Narrative Review.
Journal
Applied psychophysiology and biofeedback · 2025
PMID
40293647
RCR
3.6
Citations
10
Study type
Review
humansheart rate
State Anxiety and Nonlinear Dynamics of Heart Rate Variability in Students.
Journal
PloS one · 2016
PMID
26807793
RCR
3.4
Citations
56
Study type
Comparative study
anthropometryanxiety
Heart rate variability as a biomarker for transdiagnostic depressive and anxiety symptom trajectory in adolescents and young adults.
Journal
Journal of psychopathology and clinical science · 2024
PMID
39480332
RCR
1.6
Citations
6
Study type
Primary study
Sample size
n = 362
humansadolescent
The Association between Neuroticism and Heart Rate Variability Is Not Fully Explained by Cardiovascular Disease and Depression.
Journal
PloS one · 2016
PMID
25951236
RCR
0.8
Citations
17
Study type
Primary study
Sample size
n = 1,255
adultanxiety disorders
Your partner makes a difference. Affective touch delivered by the romantic partner improves affective state but not physiological state.
Journal
International journal of psychophysiology : official journal of the International Organization of Psychophysiology · 2026
PMID
42520858
Citations
0
Study type
Primary study
Sample size
110 men
humansmale
New insights in heart rate variability through non-linear methods for conditioning assessment in horses.
Journal
Veterinary journal (London, England : 1997) · 2026
PMID
42203068
Citations
0
Study type
Primary study
animalshorses
Heart rate variability (HRV) and posttraumatic stress disorder (PTSD): a pilot study.
Journal
Applied psychophysiology and biofeedback · 2011
PMID
20680439
RCR
7.3
Citations
178
Study type
Primary study
adultarousal
The Role of Heart Rate Variability in Mindfulness-Based Pain Relief.
Journal
The journal of pain · 2021
PMID
31377215
RCR
4.4
Citations
56
Study type
Randomized controlled trial
adolescentadult
Effects of stress management interventions on heart rate variability in adults with cardiovascular disease: a systematic review and meta-analysis.
Journal
Journal of behavioral medicine · 2024
PMID
38478157
RCR
2.3
Citations
8
Study type
Meta-analysis
Sample size
1202 participants
humansheart rate
Heart rate variability in acute psychosis.
Journal
Psychophysiology · 2004
PMID
14696725
RCR
2.6
Citations
78
Study type
Clinical trial
acute diseaseadolescent
Heart rate variability predicts alcohol craving in alcohol dependent outpatients: further evidence for HRV as a psychophysiological marker of self-regulation.
Journal
Drug and alcohol dependence · 2014
PMID
23601925
RCR
3.0
Citations
66
Study type
Primary study
adultaged
Infant emotion regulation in the context of stress: Effects of heart rate variability and temperament.
Journal
Stress and health : journal of the International Society for the Investigation of Stress · 2024
PMID
38268180
RCR
1.3
Citations
3
Study type
Primary study
Sample size
n = 108
humanstemperament
Heart rate variability in epilepsy and its association with disease duration: a retrospective case-control study.
Journal
Frontiers in neurology · 2026
PMID
42609212
Citations
0
Study type
Primary study
Sample size
360 participants
humansfemale
Smartwatch-derived exercise metrics as predictors of early hypertension: a prospective observational study.
Journal
BMC cardiovascular disorders · 2026
PMID
42252402
Citations
0
Study type
Observational study
Sample size
28 participants
humansprospective studies
Heart rate variability and emotion regulation: Multiethnic differences in reappraisal and suppression.
Journal
Emotion (Washington, D.C.) · 2026
PMID
41801708
Citations
2
Study type
Primary study
femalehumans
A pattern-based heart rate variability approach in somatic symptom disorder: Evidence from the SOMA.SSD study.
Journal
Journal of psychosomatic research · 2026
PMID
42302632
Citations
0
Study type
Primary study
Sample size
148 patients
humansheart rate
Heart Rate Variability and Blood Pressure Response to Low-Intensity Endurance Exercise Training Plus Blood Flow Restriction in Individuals with Mild Hypertension: A Randomized Controlled Clinical Trial.
Journal
Iranian journal of medical sciences · 2025
PMID
41262323
Citations
1
Study type
Randomized controlled trial
humansheart rate
Arrhythmia, heart rate variability, and antiepileptic drugs.
Journal
Epilepsia · 2010
PMID
19909327
RCR
2.9
Citations
77
Study type
Comparative study
adultaged
Clinical applicability of heart rate variability analysis by methods based on nonlinear dynamics.
Journal
Cardiac electrophysiology review · 2003
PMID
12114847
RCR
2.1
Citations
63
Study type
Review
autonomic nervous systemelectrocardiography, ambulatory
Heart rate variability analysis in patients with multiple sclerosis.
Journal
Multiple sclerosis and related disorders · 2018
PMID
29957350
RCR
1.8
Citations
29
Study type
Primary study
Sample size
25 patients
adultautonomic nervous system diseases
Genetic influences on heart rate variability.
Journal
International journal of psychophysiology : official journal of the International Organization of Psychophysiology · 2017
PMID
27114045
RCR
1.7
Citations
30
Study type
Primary study
Sample size
n = 1060
electrocardiographyelectroencephalography
Overnight Heart Rate Variability During Sleep Disturbance In Peri- And Postmenopausal Women.
Journal
Behavioral sleep medicine · 2025
PMID
37671829
RCR
0.6
Citations
2
Study type
Randomized controlled trial
humansfemale
Identifying high-risk post-infarction patients by autonomic testing - Below the tip of the iceberg.
Journal
International journal of cardiology · 2018
PMID
28343763
RCR
0.5
Citations
11
Study type
Review
autonomic nervous system diseasesdefibrillators, implantable
Heart-rate variability in sleep and wakefulness.
Journal
Cardiology · 1971
PMID
4326041
RCR
0.4
Citations
10
Study type
Primary study
adultarousal
Heart rate variability and autonomic function during sleep in fragile X syndrome
Journal
American Journal of Medical Genetics · 1999
DOI
10.1002/(sici)1096-8628(19990402)83:4<296::aid-ajmg11>3.0.co;2-d
TSH index and 24-hour mean heart rate in euthyroid adults: opposing FT3 and heart rate variability components.
Journal
Frontiers in endocrinology · 2026
PMID
42620477
Citations
0
Study type
Observational study
humansheart rate
Sex differences in regulatory mechanisms of the cardiovascular system during simulated hypokinesia.
Journal
Life sciences in space research · 2026
PMID
42601152
Citations
0
Study type
Primary study
humansmale
Heart rate variability as a predictor of mortality in patients with AA and AL amyloidosis.
Journal
European heart journal · 2002
PMID
11785998
RCR
0.9
Citations
35
Study type
Primary study
Sample size
23 patients
adultaged
Heart Rate Variability Predicts Major Adverse Cardiovascular Events and Hospitalization in Maintenance Hemodialysis Patients.
Journal
Kidney & blood pressure research · 2018
PMID
28315879
RCR
1.1
Citations
20
Study type
Primary study
Sample size
n = 179
agedcardiovascular diseases
Role of Heart Rate Variability in Association Between Glomerular Hyperfiltration and All-Cause Mortality.
Journal
Journal of the American Heart Association · 2022
PMID
34889105
RCR
0.8
Citations
9
Study type
Primary study
Sample size
1615 participants
agedaged, 80 and over
Impedance cardiography and heart rate variability for long-term cardiovascular outcome prediction after myocardial infarction.
Journal
Medicina (Kaunas, Lithuania) · 2013
PMID
23032907
RCR
0.4
Citations
10
Study type
Primary study
agedcardiography, impedance
Heart rate variability during night sleep and after awakening in overtrained athletes.
Journal
Medicine and science in sports and exercise · 2006
PMID
16531900
RCR
3.5
Citations
88
Study type
Primary study
Sample size
6 men
adultanalysis of variance
Posttraumatic stress, heart rate variability, and the mediating role of behavioral health risks.
Journal
Psychosomatic medicine · 2015
PMID
25264973
RCR
3.2
Citations
71
Study type
Primary study
adolescentadult
Procedural memory consolidation is associated with heart rate variability and sleep spindles.
Journal
Journal of sleep research · 2021
PMID
31454120
RCR
0.7
Citations
11
Study type
Primary study
Sample size
n = 20
adultfemale
The subjective sleep quality and heart rate variability in hemodialysis patients.
Journal
Renal failure · 2011
PMID
21332330
RCR
0.6
Citations
12
Study type
Primary study
Sample size
n = 50
agedautonomic nervous system
Changes and prognostic significance of autonomic cardiac regulation during ageing.
Journal
Autonomic neuroscience : basic & clinical · 2025
PMID
40023882
Citations
0
Study type
Primary study
humansheart rate
Null-Result Studies2
Disconnection Between Self-Reported Wellbeing and Heart Rate Variability from Wearables.
Journal
Sensors (Basel, Switzerland) · 2026
PMID
41755264
Citations
0
Study type
Primary study
Sample size
n = 21
Bears on
Secondary point
humansheart rate
Theories of Arousal Predict a Link Between Heart Rate Variability and Reactive Aggression: Meta-Analytic Results Disagree.
Journal
Aggressive behavior · 2024
PMID
39513333
RCR
0.6
Citations
2
Study type
Meta-analysis
Bears on
Secondary point
humansaggression
Letters, Editorials and Comments (not counted in the rating)5
Heart rate variability, but not heart rate, is associated with handgrip strength and mortality in older Africans at very low cardiovascular risk: A population-based study.
Journal
International journal of cardiology · 2016
PMID
25863303
RCR
1.1
Citations
22
agedcardiovascular diseases
Nighttime heart rate variability, overnight urinary norepinephrine, and glycemic status in apparently healthy human adults.
Journal
International journal of cardiology · 2014
PMID
23651814
RCR
0.5
Citations
13
blood glucosecircadian rhythm
Heart rate variability in healthy subjects: effect of age and derivation of normal ranges for tests of autonomic function.
Journal
British heart journal · 1987
PMID
3801254
RCR
0.3
Citations
8
age factorsheart function tests
Heart rate variability and sleep.
Journal
Circulation · 1996
PMID
8653852
RCR
0.1
Citations
3
circadian rhythmheart diseases
Indicators of heart rate variability, urinary norepinephrine and plasma lipid levels in healthy adults.
Journal
International journal of cardiology · 2014
PMID
23871333
RCR
0.0
Citations
1
cholesterolcircadian rhythm
Evidence on: Consumer wearable devices measure HRV with sufficient agreement to a validated reference to be meaningful.
30 scored
Anchor Studies7
The Validity of Apple Watch Series 9 and Ultra 2 for Serial Measurements of Heart Rate Variability and Resting Heart Rate.
Journal
Sensors (Basel, Switzerland) · 2024
PMID
39409260
RCR
5.9
Citations
16
Study type
Primary study
humansheart rate
Validation of nocturnal resting heart rate and heart rate variability in consumer wearables.
Journal
Physiological reports · 2025
PMID
40834291
RCR
3.7
Citations
10
Study type
Validity study
humansheart rate
Can Wearable Devices Accurately Measure Heart Rate Variability? A Systematic Review.
Journal
Folia medica · 2019
PMID
29668452
RCR
8.7
Citations
131
Study type
Systematic review
electrocardiographyexercise
Deriving Accurate Nocturnal Heart Rate, rMSSD and Frequency HRV from the Oura Ring.
Journal
Sensors (Basel, Switzerland) · 2024
PMID
39686012
RCR
2.6
Citations
8
Study type
Primary study
humansheart rate
A Comparative Study Between ECG- and PPG-Based Heart Rate Sensors for Heart Rate Variability Measurements: Influence of Body Position, Duration, Sex, and Age.
Journal
Sensors (Basel, Switzerland) · 2025
PMID
41012985
RCR
3.1
Citations
8
Study type
Comparative study
humansheart rate
Limited Validity of the Low-Cost Coospo H808S Heart-Rate Monitor Compared to the Polar H10.
Journal
International journal of sports physiology and performance · 2025
PMID
40615117
Citations
1
Study type
Validity study
humansheart rate
Publication guidelines for human heart rate and heart rate variability studies in psychophysiology-Part 1: Physiological underpinnings and foundations of measurement.
Journal
Psychophysiology · 2024
PMID
38873876
RCR
59.6
Citations
181
Study type
Guideline
humansautonomic nervous system
Supporting Studies20
Comparative analysis of heart rate variability indices from ballistocardiogram and electrocardiogram: a study on measurement agreement.
Journal
Heart and vessels · 2025
PMID
39672926
Citations
0
Study type
Comparative study
Sample size
25 individuals
humansmale
Reliability of resting-state photoplethysmogram-based pulse rate variability in lifespan samples: implications for cardiovascular research.
Journal
Physiological measurement · 2026
PMID
42055071
Citations
0
Study type
Primary study
Sample size
n = 536
humansphotoplethysmography
Butterworth Filtering at 500 Hz Optimizes PPG-Based Heart Rate Variability Analysis for Wearable Devices: A Comparative Study.
Journal
Sensors (Basel, Switzerland) · 2025
PMID
41305298
Citations
0
Study type
Comparative study
Sample size
n = 10
humansheart rate
Effects of electrocardiographic noise on ultra-short term Heart Rate Variability indices.
Journal
Computers in biology and medicine · 2025
PMID
40773995
Citations
1
Study type
Primary study
humansheart rate
Kubios HRV--heart rate variability analysis software.
Journal
Computer methods and programs in biomedicine · 2014
PMID
24054542
RCR
85.6
Citations
1,745
Study type
Primary study
algorithmsheart rate
Optimizing Intersession Reliability of Heart Rate Variability-The Effects of Artifact Correction and Breathing Type.
Journal
Journal of strength and conditioning research · 2021
PMID
33105371
RCR
2.1
Citations
22
Study type
Primary study
Sample size
41 participants
adolescentartifacts
Intra-day and inter-day reliability of heart rate variability measurement.
Journal
Journal of sports sciences · 2013
PMID
22963409
RCR
2.3
Citations
44
Study type
Comparative study
Sample size
99 participants
analysis of variancecircadian rhythm
Test-retest reliability of time- and frequency-domain measures of short-term resting heart rate variability in a healthy young population.
Journal
International journal of psychophysiology : official journal of the International Organization of Psychophysiology · 2026
PMID
41765049
Citations
0
Study type
Primary study
Sample size
116 participants
humansheart rate
A quantitative systematic review of normal values for short-term heart rate variability in healthy adults.
Journal
Pacing and clinical electrophysiology : PACE · 2011
PMID
20663071
RCR
21.2
Citations
553
Study type
Systematic review
Sample size
21,438 participants
adultfemale
Reference values for time- and frequency-domain heart rate variability measures.
Journal
Heart rhythm · 2018
PMID
26883166
RCR
4.9
Citations
93
Study type
Primary study
adultautonomic nervous system
Validity and reliability of short-term heart-rate variability from the Polar S810.
Journal
Medicine and science in sports and exercise · 2009
PMID
19092682
RCR
9.0
Citations
217
Study type
Validity study
adultalgorithms
Evaluation of HRV-PRV agreement with autoencoder-based signal quality assessment in resting and dynamic conditions.
Journal
Physiological measurement · 2026
PMID
42556396
Citations
0
Study type
Primary study
Sample size
15 volunteers
humansautoencoder
Heart Rate Variability Analysis on CEBS Database Signals.
Journal
Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference · 2019
PMID
30441629
RCR
0.7
Citations
9
Study type
Primary study
electrocardiographyheart rate
The Novel Estimation Algorithm of Heart Rate Variability and Stress Using Facial Video Analysis.
Journal
Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference · 2025
PMID
40039066
RCR
0.0
Citations
0
Study type
Primary study
humansheart rate
Hybrid CNN-LSTM Model for Evaluating Heart Rate Variability from Pulse-to-Pulse Intervals.
Journal
Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference · 2025
PMID
41336669
Citations
0
Study type
Primary study
Sample size
19 subjects
humansheart rate
Validation of the ultra short term heart rate variability measures under changing psychophysiological state of the healthy participants at rest.
Journal
Scientific reports · 2026
PMID
42243172
Citations
0
Study type
Primary study
humansheart rate
Reproducibility of 24-h heart rate variability in children.
Journal
Clinical autonomic research : official journal of the Clinical Autonomic Research Society · 2018
PMID
28667574
RCR
0.3
Citations
5
Study type
Primary study
adolescentaging
Validity of the Polar H7 Heart Rate Sensor for Heart Rate Variability Analysis during Exercise in Different Age, Body Composition and Fitness Level Groups.
Journal
Sensors (Basel, Switzerland) · 2021
PMID
33572800
RCR
4.6
Citations
42
Study type
Primary study
adultaged
Validity of Heart Rate Variability Measured with Apple Watch Series 6 Compared to Laboratory Measures.
Journal
Sensors (Basel, Switzerland) · 2025
PMID
40285070
RCR
3.7
Citations
9
Study type
Primary study
Sample size
n = 78
wearable electronic devicesheart rate determination
Accuracy of Photoplethysmography-Derived Pulse Rate Variability Compared with Electrocardiography-Derived Heart Rate Variability: A Systematic Review and Meta-Analysis.
Journal
Sensors (Basel, Switzerland) · 2026
PMID
42655500
Citations
0
Study type
Meta-analysis
photoplethysmographyhumans
Conflicting Studies3
Signal Quality Assessment and Reconstruction of PPG-Derived Signals for Heart Rate and Variability Estimation in In-Vehicle Applications: A Comparative Review and Empirical Validation.
Journal
Sensors (Basel, Switzerland) · 2025
PMID
41471550
RCR
2.4
Citations
6
Study type
Comparative study
Bears on
Secondary point
humansheart rate
The reliability of short-term measurements of heart rate variability.
Journal
International journal of cardiology · 2005
PMID
16098384
RCR
7.4
Citations
208
Study type
Review
Bears on
Core claim
heart ratehumans
Reliability and inter-device agreement of multi-site heart rate variability measurements during transcutaneous auricular vagus nerve stimulation: a prospective single-arm methodological physiological study.
Journal
BMC cardiovascular disorders · 2026
PMID
42859155
Citations
0
Study type
Clinical trial
Bears on
Secondary point
adultfemale
Evidence on: Higher trait neuroticism is associated with lower resting heart rate variability.
8 scored
Anchor Studies2
The Association between Neuroticism and Heart Rate Variability Is Not Fully Explained by Cardiovascular Disease and Depression.
Journal
PloS one · 2016
PMID
25951236
RCR
0.8
Citations
17
Study type
Primary study
Sample size
n = 1,255
adultanxiety disorders
Determinants of heart rate variability in the general population: The Lifelines Cohort Study.
Journal
Heart rhythm · 2019
PMID
29753022
RCR
3.8
Citations
62
Study type
Primary study
Sample size
n = 149,205
adolescentadult
Supporting Studies5
Neuroticism's importance in understanding the daily life correlates of heart rate variability.
Journal
Emotion (Washington, D.C.) · 2010
PMID
20677870
RCR
1.2
Citations
28
Study type
Primary study
activities of daily livingaffect
Decreased heart rate variability during emotion regulation in subjects at risk for psychopathology.
Journal
Psychological medicine · 2012
PMID
22067596
RCR
2.9
Citations
67
Study type
Primary study
Sample size
n = 13
adultanalysis of variance
Measures of the psychophysiological response to recurrent anticipatory stress - the influence of neuroticism on heart rhythm and skin resistance.
Journal
Scientific reports · 2026
PMID
41272229
Citations
1
Study type
Primary study
humansheart rate
Relationship between neuroticism, threat of shock and heart rate variability reactivity.
Journal
International maritime health · 2014
PMID
23788220
RCR
0.1
Citations
2
Study type
Primary study
adolescentadult
Neuroticism and extraversion in relation to physiological stress reactivity during adolescence.
Journal
Biological psychology · 2017
PMID
26956979
RCR
2.0
Citations
34
Study type
Primary study
Sample size
n = 327
adolescentadolescent development
Null-Result Studies1
Association of negative affect with resting heart rate variability in medical students.
Journal
Biological psychology · 2025
PMID
40541707
Citations
0
Study type
Primary study
Sample size
294 women
Bears on
Core claim
humansheart rate
Evidence on: Resting heart rate variability declines with age in healthy people.
10 scored
Anchor Studies5
Reference values for time- and frequency-domain heart rate variability measures.
Journal
Heart rhythm · 2018
PMID
26883166
RCR
4.9
Citations
93
Study type
Primary study
adultautonomic nervous system
Effect of age and sex on heart rate variability in healthy subjects.
Journal
Journal of manipulative and physiological therapeutics · 2007
PMID
17574955
RCR
5.8
Citations
161
Study type
Primary study
Sample size
470 subjects
adolescentadult
A quantitative systematic review of normal values for short-term heart rate variability in healthy adults.
Journal
Pacing and clinical electrophysiology : PACE · 2011
PMID
20663071
RCR
21.2
Citations
553
Study type
Systematic review
Sample size
21,438 participants
adultfemale
Reference values for short-term resting-state heart rate variability in healthy adults: Results from the Brazilian Longitudinal Study of Adult Health-ELSA-Brasil study.
Journal
Psychophysiology · 2019
PMID
29292837
RCR
3.7
Citations
53
Study type
Primary study
adultaged
Changes and prognostic significance of autonomic cardiac regulation during ageing.
Journal
Autonomic neuroscience : basic & clinical · 2025
PMID
40023882
Citations
0
Study type
Primary study
humansheart rate
Supporting Studies3
Comprehensive linear and nonlinear heart rate variability normative data in children.
Journal
Clinical autonomic research : official journal of the Clinical Autonomic Research Society · 2025
PMID
39249159
RCR
2.6
Citations
6
Study type
Primary study
Sample size
247 patients
humansheart rate
Heart rate variability: reference values and role for clinical profile and mortality in individuals with heart failure.
Journal
Clinical research in cardiology : official journal of the German Cardiac Society · 2024
PMID
37422841
RCR
9.6
Citations
35
Study type
Primary study
Sample size
n = 3289
humansfemale
Normative Values of Short-Term Heart Rate Variability Parameters in Koreans and Their Clinical Value for the Prediction of Mortality.
Journal
Heart, lung & circulation · 2018
PMID
28592377
RCR
1.3
Citations
19
Study type
Primary study
adultaged
Conflicting Studies2
Ethnic differences in resting heart rate variability: a systematic review and meta-analysis.
Journal
Psychosomatic medicine · 2015
PMID
25551201
RCR
7.3
Citations
144
Study type
Meta-analysis
Bears on
Secondary point
black or african americancardiovascular diseases
Age-related losses in cardiac autonomic activity during a daytime nap.
Journal
Psychophysiology · 2022
PMID
33048396
RCR
2.1
Citations
23
Study type
Primary study
Bears on
Secondary point
adultaged
Evidence on: A fall in overnight heart rate variability precedes the onset of an acute infection.
5 scored
Anchor Studies1
Heart rate variability in female soccer players, before, during, and after a COVID-19 positive test.
Journal
Scientific reports · 2025
PMID
40634557
Citations
0
Study type
Primary study
humansfemale
Supporting Studies4
Real-time infection prediction with wearable physiological monitoring and AI to aid military workforce readiness during COVID-19.
Journal
Scientific reports · 2022
PMID
35260671
RCR
3.6
Citations
37
Study type
Primary study
algorithmsarea under curve
Detection of COVID-19 using multimodal data from a wearable device: results from the first TemPredict Study.
Journal
Scientific reports · 2022
PMID
35236896
RCR
4.5
Citations
53
Study type
Primary study
Sample size
63,153 participants
adolescentadult
Using Patient-Held Devices to Measure Variations in Resting Heart Rate and Step Count Prior to Presentation With an Acute Illness: International, Multicenter Flash Mob Feasibility Study.
Journal
JMIR cardio · 2025
PMID
41397288
Citations
0
Study type
Observational study
Sample size
n = 17
humansheart rate
Day-to-day reliability of basal heart rate and short-term and ultra short-term heart rate variability assessment by the Equivital eq02+ LifeMonitor in US Army soldiers.
Journal
BMJ military health · 2025
PMID
39004444
RCR
2.2
Citations
5
Study type
Primary study
humansmilitary personnel
Evidence on: Acute alcohol consumption lowers heart rate variability.
5 scored
Anchor Studies2
Acute alcohol consumption and arrhythmias in young adults: the MunichBREW II study.
Journal
European heart journal · 2024
PMID
39363568
RCR
4.2
Citations
20
Study type
Primary study
Sample size
202 volunteers
humansmale
Heart rate variability in alcohol use: A review.
Journal
Pharmacology, biochemistry, and behavior · 2020
PMID
30529588
RCR
4.9
Citations
73
Study type
Review
adolescentadult
Supporting Studies3
The level of acute alcohol exposure during binge drinking associates with the extent of cardiac response.
Journal
Clinical research in cardiology : official journal of the German Cardiac Society · 2026
PMID
40828179
Citations
0
Study type
Primary study
Sample size
193 participants
humansbinge drinking
Characteristics of heart rate variability in alcohol-dependent subjects and nondependent chronic alcohol users.
Journal
Alcoholism, clinical and experimental research · 2014
PMID
24117482
RCR
2.5
Citations
50
Study type
Review
alcohol drinkingalcoholism
Heart rate variability as a potential biomarker for alcohol use disorders: A systematic review and meta-analysis.
Journal
Drug and alcohol dependence · 2020
PMID
31494439
RCR
3.9
Citations
56
Study type
Meta-analysis
alcoholismautonomic nervous system
Evidence on: Regular exercise training increases heart rate variability.
7 scored
Anchor Studies3
The effect of exercise training on heart rate variability in patients with hypertension: A systematic review and meta-analysis.
Journal
Journal of sports sciences · 2024
PMID
39115012
RCR
2.9
Citations
12
Study type
Meta-analysis
humansheart rate
Beneficial impacts of physical activity on heart rate variability: A systematic review and meta-analysis.
Journal
PloS one · 2024
PMID
38578755
RCR
11.1
Citations
38
Study type
Meta-analysis
humanscardiovascular diseases
Effect of exercise training on heart rate variability in type 2 diabetes mellitus patients: A systematic review and meta-analysis.
Journal
PloS one · 2021
PMID
33999947
RCR
7.9
Citations
88
Study type
Meta-analysis
Sample size
n = 21
diabetes mellitus, type 2diabetic neuropathies
Supporting Studies3
Exercise Frequency Determines Heart Rate Variability Gains in Older People: A Meta-Analysis and Meta-Regression.
Journal
Sports medicine (Auckland, N.Z.) · 2020
PMID
30945205
RCR
3.7
Citations
51
Study type
Meta-analysis
Sample size
111 subjects
agedaging
Monitoring Athletic Training Status Through Autonomic Heart Rate Regulation: A Systematic Review and Meta-Analysis.
Journal
Sports medicine (Auckland, N.Z.) · 2017
PMID
26888648
RCR
12.6
Citations
207
Study type
Meta-analysis
athletic performanceautonomic nervous system
Physical activity and heart rate variability in older adults: the Cardiovascular Health Study.
Journal
Circulation · 2014
PMID
24799513
RCR
7.5
Citations
171
Study type
Randomized controlled trial
agedcardiovascular diseases
Null-Result Studies1
Effects of aerobic training intensity on resting, exercise and post-exercise blood pressure, heart rate and heart-rate variability.
Journal
Journal of human hypertension · 2010
PMID
19554028
RCR
5.4
Citations
144
Study type
Randomized controlled trial
Bears on
Secondary point
agedblood pressure
Evidence on: Heart rate variability biofeedback reduces anxiety.
8 scored
Anchor Studies2
The effect of heart rate variability biofeedback training on stress and anxiety: a meta-analysis.
Journal
Psychological medicine · 2018
PMID
28478782
RCR
21.3
Citations
361
Study type
Meta-analysis
Sample size
484 participants
anxietyanxiety disorders
Psychophysiological effects of heart rate variability biofeedback versus sham biofeedback: A randomized controlled trial.
Journal
Biological psychology · 2026
PMID
41905438
Citations
0
Study type
Randomized controlled trial
Sample size
n = 47
humansbiofeedback, psychology
Supporting Studies4
Impact of a brief HRV-biofeedback intervention on emotion regulation following a real-life stressful event: A randomized controlled study.
Journal
Behaviour research and therapy · 2026
PMID
41702143
Citations
0
Study type
Randomized controlled trial
Sample size
n = 122
humansbiofeedback, psychology
Physical activity, mindfulness meditation, or heart rate variability biofeedback for stress reduction: a randomized controlled trial.
Journal
Applied psychophysiology and biofeedback · 2016
PMID
26111942
RCR
7.6
Citations
142
Study type
Randomized controlled trial
Sample size
126 participants
adultanxiety
Efficacy and Methodology of Remote Heart Rate Variability Biofeedback Interventions for Mental Health: A Systematic Review and Meta-Analysis.
Journal
Applied psychophysiology and biofeedback · 2026
PMID
41310318
Citations
4
Study type
Meta-analysis
Sample size
1352 subjects
humansheart rate
Feasibility and Effectiveness of Portable/Remote Heart Rate Variability (HRV) Biofeedback Training in Treating Stress and Mental Health Difficulties: A Systematic Review.
Journal
Applied psychophysiology and biofeedback · 2026
PMID
41364320
Citations
0
Study type
Systematic review
humansheart rate
Null-Result Studies2
Effects of Heart Rate Variability Biofeedback Training on Anxiety Reduction and Brain Activity: a Randomized Active-Controlled Study Using EEG.
Journal
Applied psychophysiology and biofeedback · 2024
PMID
38888656
RCR
2.8
Citations
8
Study type
Randomized controlled trial
Bears on
Core claim
humansheart rate
A Randomized Sham-Controlled Trial of Heart Rate Variability Biofeedback Following Traumatic Brain Injury (TBI).
Journal
Applied psychophysiology and biofeedback · 2026
PMID
40828260
Citations
0
Study type
Randomized controlled trial
Bears on
Core claim
humansmale
Evidence on: Slow-paced breathing raises heart rate variability more than breathing at a normal rate.
5 scored
Anchor Studies1
Effect of Resonance Breathing on Heart Rate Variability and Cognitive Functions in Young Adults: A Randomised Controlled Study.
Journal
Cureus · 2022
PMID
35308668
RCR
3.4
Citations
24
Study type
Primary study
Supporting Studies2
Efficacy of Paced Breathing at the Low-frequency Peak on Heart Rate Variability and Baroreflex Sensitivity.
Journal
Applied psychophysiology and biofeedback · 2020
PMID
31781925
RCR
1.5
Citations
18
Study type
Primary study
adultautonomic nervous system
Heart Rate and Breathing Are Not Always in Phase During Resonance Frequency Breathing.
Journal
Applied psychophysiology and biofeedback · 2020
PMID
32285231
RCR
2.2
Citations
26
Study type
Primary study
Sample size
24 adults
adolescentadult
Conflicting Studies1
Comparison of slow-paced breathing interventions with and without an inhalation-hold on physiological outcomes: A randomized cross-over pilot study.
Journal
International journal of psychophysiology : official journal of the International Organization of Psychophysiology · 2026
PMID
42385999
Citations
0
Study type
Randomized controlled trial
Sample size
n = 32
Bears on
Secondary point
humansfemale
Null-Result Studies1
Breathing slower is not always better: Slow-paced breathing enhances heart rate variability but produces age-differential effects on emotional reactivity and memory.
Journal
International journal of psychophysiology : official journal of the International Organization of Psychophysiology · 2026
PMID
42173198
Citations
0
Study type
Primary study
Sample size
n = 82
Bears on
Core claim
humansheart rate
Evidence on: Heart rate variability biofeedback reduces craving in substance use disorder.
2 scored
Anchor Studies1
Heart Rate Variability Biofeedback for Substance Use Disorder: A Randomized Clinical Trial.
Journal
JAMA psychiatry · 2025
PMID
41032322
RCR
2.1
Citations
6
Study type
Randomized controlled trial
Sample size
260 individuals
humansfemale
Supporting Studies1
Theoretical implications and clinical support for heart rate variability biofeedback for substance use disorders.
Journal
Current opinion in psychology · 2020
PMID
31055246
RCR
1.4
Citations
21
Study type
Review
biofeedback, psychologyheart rate
Evidence on: People with major depression have lower resting heart rate variability.
11 scored
Anchor Studies3
A meta-analysis of heart rate variability and psychopathology: An investigation guided by the hierarchical taxonomy of psychopathology framework.
Journal
Journal of psychopathology and clinical science · 2026
PMID
42490257
Citations
0
Study type
Meta-analysis
Sample size
n = 62,264
humansheart rate
Divergence of clinical and autonomic recovery in adolescent major depressive disorder: A 10-week prospective heart rate variability study with nocturnal electrocardiogram monitoring.
Journal
Journal of affective disorders · 2026
PMID
42107656
Citations
0
Study type
Primary study
Sample size
n = 43
humansmajor depressive disorder
A meta-analysis of heart rate variability in major depression.
Journal
Psychological medicine · 2020
PMID
31239003
RCR
21.8
Citations
341
Study type
Meta-analysis
adultcardiovascular diseases
Supporting Studies6
Autonomic dysfunction and heart rate variability in depression.
Journal
Stress (Amsterdam, Netherlands) · 2016
PMID
26004818
RCR
11.5
Citations
250
Study type
Review
animalsautonomic nervous system
Heart and soul: heart rate variability and major depression.
Journal
Behavioural pharmacology · 2019
PMID
29543649
RCR
1.9
Citations
34
Study type
Review
animalsantidepressive agents
Heart Rate Variability, Sleep Quality, and Depression in the Context of Chronic Stress.
Journal
Annals of behavioral medicine : a publication of the Society of Behavioral Medicine · 2021
PMID
32525208
RCR
7.9
Citations
82
Study type
Primary study
adultcaregivers
Usefulness of heart rate variability indices in assessing the risk of an unsuccessful return to work after sick leave in depressed patients.
Journal
Neuropsychopharmacology reports · 2021
PMID
32627417
RCR
0.7
Citations
7
Study type
Primary study
Sample size
n = 30
adultmajor depressive disorder
The role of change in peripartum heart rate variability in the prediction of depressive symptoms 18 months after childbirth: a follow-up study.
Journal
Journal of psychiatric research · 2026
PMID
41780443
Citations
0
Study type
Primary study
humansfemale
The effects of non-pharmacological interventions on vagally-mediated heart rate variability (vmHRV) in individuals with depression: A systematic review and meta-analysis.
Journal
Neuroscience and biobehavioral reviews · 2025
PMID
40721201
Citations
4
Study type
Meta-analysis
humansdepression
Conflicting Studies1
Heart rate variability as a biomarker for transdiagnostic depressive and anxiety symptom trajectory in adolescents and young adults.
Journal
Journal of psychopathology and clinical science · 2024
PMID
39480332
RCR
1.6
Citations
6
Study type
Primary study
Sample size
n = 362
Bears on
Secondary point
humansadolescent
Null-Result Studies1
Heart rate variability in mental disorders: an umbrella review of meta-analyses.
Journal
Translational psychiatry · 2025
PMID
40155386
RCR
9.4
Citations
26
Study type
Systematic review
Sample size
n = 442
Bears on
Core claim
humansheart rate
Evidence on: People with an anxiety disorder have lower resting heart rate variability.
6 scored
Anchor Studies3
A meta-analysis of heart rate variability and psychopathology: An investigation guided by the hierarchical taxonomy of psychopathology framework.
Journal
Journal of psychopathology and clinical science · 2026
PMID
42490257
Citations
0
Study type
Meta-analysis
Sample size
n = 62,264
humansheart rate
How Much Does Stress Cost? A Case-Control Study on Vagally Mediated Heart Rate Variability Responses in Anxious and Non-Anxious Individuals During a Cognitive Task.
Journal
Medical sciences (Basel, Switzerland) · 2025
PMID
41003154
Citations
0
Study type
Primary study
humansheart rate
Altered autonomic stress reactivity and recovery in panic disorder during the Trier Social Stress Test.
Journal
Journal of affective disorders · 2026
PMID
41850612
Citations
0
Study type
Primary study
humanspanic disorder
Supporting Studies2
The role of perseverative cognition and heart rate variability in high trait anxiety.
Journal
International journal of psychophysiology : official journal of the International Organization of Psychophysiology · 2025
PMID
41197776
Citations
0
Study type
Primary study
humansheart rate
Heart Rate Variability Moderates the Association Between Trait Anxiety and Sympathetic Nerve Activity in Humans.
Journal
Hypertension (Dallas, Tex. : 1979) · 2026
PMID
41717699
Citations
3
Study type
Primary study
Sample size
130 adults
humansfemale
Null-Result Studies1
Heart rate variability in mental disorders: an umbrella review of meta-analyses.
Journal
Translational psychiatry · 2025
PMID
40155386
RCR
9.4
Citations
26
Study type
Systematic review
Sample size
n = 442
Bears on
Core claim
humansheart rate
Evidence on: Antidepressant treatment lowers heart rate variability.
2 scored
Anchor Studies1
Heart rate variability during antidepressant treatment with venlafaxine and mirtazapine.
Journal
Clinical neuropharmacology · 2014
PMID
24201230
RCR
1.2
Citations
27
Study type
Randomized controlled trial
Sample size
n = 20
adultantidepressive agents
Null-Result Studies1
The Effects of Antidepressants and Quetiapine on Heart Rate Variability.
Journal
Pharmacopsychiatry · 2017
PMID
27023265
RCR
1.2
Citations
22
Study type
Primary study
Sample size
n = 19
Bears on
Core claim
adultaged
Evidence on: Lower heart rate variability predicts reactive aggression.
1 scored
Null-Result Studies1
Theories of Arousal Predict a Link Between Heart Rate Variability and Reactive Aggression: Meta-Analytic Results Disagree.
Journal
Aggressive behavior · 2024
PMID
39513333
RCR
0.6
Citations
2
Study type
Meta-analysis
Bears on
Core claim
humansaggression
Evidence on: Acute THC lowers heart rate variability.
1 scored
Anchor Studies1
Acute effects of oral delta-9-tetrahydrocannabinol (THC) on autonomic cardiac activity and their relation to subjective and anxiogenic effects.
Journal
Psychophysiology · 2022
PMID
34665890
RCR
2.5
Citations
19
Study type
Primary study
administration, oraladult
Evidence on: Higher indoor fine-particulate exposure lowers heart rate variability.
1 scored
Anchor Studies1
Heart rate variability, electrodermal activity and cognition in adults: Association with short-term indoor PM2.5 exposure in a real-world intervention study.
Journal
Environmental research · 2024
PMID
39490569
RCR
1.8
Citations
7
Study type
Randomized controlled trial
Sample size
n = 40
adultfemale
Evidence on: Heart rate variability follows a consistent pattern across the menstrual cycle.
3 scored
Anchor Studies1
Wearable-measured heart rate variability and premenstrual disorder symptoms across menstrual cycle.
Journal
Archives of women's mental health · 2026
PMID
42412242
Citations
2
Study type
Primary study
Sample size
193 participants
humansfemale
Conflicting Studies1
Variations in Estrogen, Progesterone, and Nocturnal Physiology are not Associated with Performance and Sleep within and between Menstrual Cycles.
Journal
Medicine and science in sports and exercise · 2026
PMID
41747284
Citations
0
Study type
Primary study
Bears on
Secondary point
humansfemale
Null-Result Studies1
Cardiac autonomic regulation across the menstrual cycle is highly individual: evidence from phase-aligned cyclic generalized additive mixed models.
Journal
American journal of physiology. Regulatory, integrative and comparative physiology · 2026
PMID
42012497
Citations
1
Study type
Primary study
Bears on
Core claim
humansfemale
Evidence on: Beta blockers lower heart rate variability.
3 scored
Conflicting Studies1
Effect of atenolol versus ivabradine on heart rate variability in patients of schizophrenia with clozapine-induced tachycardia: a randomized controlled trial.
Journal
Psychiatry research · 2026
PMID
42567080
Citations
0
Study type
Randomized controlled trial
Bears on
Core claim
adultfemale
Null-Result Studies2
Effect of propranolol on heart rate variability in hyperthyroidism.
Journal
BMC research notes · 2018
PMID
29471876
RCR
0.5
Citations
10
Study type
Primary study
Bears on
Core claim
adrenergic beta-antagonistsadult
Effects of low-dose metoprolol succinate sustained-release tablets on patients with paroxysmal atrial fibrillation undergoing circumferential pulmonary vein isolation: a retrospective cohort study.
Journal
BMC cardiovascular disorders · 2025
PMID
41013292
Citations
1
Study type
Primary study
Sample size
67 patients
Bears on
Core claim
humansatrial fibrillation
Evidence on: A chest-strap heart rate monitor agrees with ECG for HRV at rest.
5 scored
Anchor Studies2
Validity of the Polar H10 for heart rate variability and cardiac autonomic reflex tests.
Journal
Autonomic neuroscience : basic & clinical · 2026
PMID
42275859
Citations
2
Study type
Validity study
humansheart rate
Validity of the Polar H7 Heart Rate Sensor for Heart Rate Variability Analysis during Exercise in Different Age, Body Composition and Fitness Level Groups.
Journal
Sensors (Basel, Switzerland) · 2021
PMID
33572800
RCR
4.6
Citations
42
Study type
Primary study
adultaged
Supporting Studies3
Can Wearable Devices Accurately Measure Heart Rate Variability? A Systematic Review.
Journal
Folia medica · 2019
PMID
29668452
RCR
8.7
Citations
131
Study type
Systematic review
electrocardiographyexercise
Limited Validity of the Low-Cost Coospo H808S Heart-Rate Monitor Compared to the Polar H10.
Journal
International journal of sports physiology and performance · 2025
PMID
40615117
Citations
1
Study type
Validity study
humansheart rate
Validity of a Smartphone Application and Chest Strap for Recording RR Intervals at Rest in Athletes.
Journal
International journal of sports physiology and performance · 2020
PMID
32163924
RCR
2.7
Citations
31
Study type
Validity study
adultelectrocardiography
Evidence on: A heart rate variability recording shorter than five minutes gives a reliable RMSSD.
4 scored
Anchor Studies1
Ultra-short heart rate variability recording reliability: The effect of controlled paced breathing.
Journal
Annals of noninvasive electrocardiology : the official journal of the International Society for Holter and Noninvasive Electrocardiology, Inc · 2019
PMID
29863781
RCR
2.9
Citations
40
Study type
Primary study
adolescentadult
Supporting Studies2
Short-term heart rate variability in resting conditions: methodological considerations.
Journal
Kardiologia polska · 2021
PMID
34227676
RCR
3.3
Citations
31
Study type
Primary study
heart ratehumans
Heart Rate Variability in Anorexia Nervosa: A Systematic Review and Meta-Analysis on the Moderating Role of Measurement Duration and Clinical Stage.
Journal
European eating disorders review : the journal of the Eating Disorders Association · 2026
PMID
41873160
Citations
2
Study type
Meta-analysis
Sample size
805 participants
humansheart rate
Conflicting Studies1
Validity of Smartphone Heart Rate Variability Pre- and Post-Resistance Exercise.
Journal
Sensors (Basel, Switzerland) · 2021
PMID
33050249
RCR
1.3
Citations
12
Study type
Primary study
Bears on
Secondary point
adultelectrocardiography
Evidence on: Low heart rate variability predicts mortality in people with heart failure.
4 scored
Anchor Studies2
Heart rate variability as predictive factor for sudden cardiac death.
Journal
Aging · 2019
PMID
29476045
RCR
11.8
Citations
202
Study type
Review
asymptomatic diseasesdeath, sudden, cardiac
Heart rate variability: reference values and role for clinical profile and mortality in individuals with heart failure.
Journal
Clinical research in cardiology : official journal of the German Cardiac Society · 2024
PMID
37422841
RCR
9.6
Citations
35
Study type
Primary study
Sample size
n = 3289
humansfemale
Supporting Studies2
Heart Rate Variability Triangular Index as a Predictor of Cardiovascular Mortality in Patients With Atrial Fibrillation.
Journal
Journal of the American Heart Association · 2021
PMID
32750290
RCR
4.0
Citations
53
Study type
Primary study
Sample size
1922 patients
agedatrial fibrillation
Heart Rate Variability and Prognosis in Hemodialysis Patients: A Meta-Analysis.
Journal
Blood purification · 2021
PMID
33291108
RCR
1.9
Citations
20
Study type
Meta-analysis
cardiovascular diseasesheart disease risk factors
Evidence on: Wrist-wearable heart rate variability identifies posttraumatic neuropsychiatric symptoms after trauma exposure.
5 scored
Anchor Studies1
Heart rate variability wrist-wearable biomarkers identify adverse posttraumatic neuropsychiatric sequelae after traumatic stress exposure.
Journal
Psychiatry research · 2024
PMID
39549594
RCR
1.8
Citations
7
Study type
Observational study
humansmale
Supporting Studies4
Long-term impact of combat-related traumatic injury on heart rate variability: findings from the ADVANCE study.
Journal
BMJ military health · 2026
PMID
40664473
Citations
1
Study type
Primary study
humansheart rate
Predicting high anger intensity using ecological momentary assessment and wearable-derived physiological data in a trauma-affected sample.
Journal
European journal of psychotraumatology · 2025
PMID
40135377
Citations
1
Study type
Primary study
Sample size
n = 84
humansanger
Heart rate variability in mental disorders: an umbrella review of meta-analyses.
Journal
Translational psychiatry · 2025
PMID
40155386
RCR
9.4
Citations
26
Study type
Systematic review
Sample size
n = 442
humansheart rate
Resting respiratory sinus arrhythmia and posttraumatic stress disorder: A meta-analysis.
Journal
Biological psychology · 2019
PMID
30779926
RCR
4.8
Citations
71
Study type
Meta-analysis
adolescentadult
Evidence on: An HRV algorithm on a wearable ECG detects seizures in patients with marked ictal autonomic change.
3 scored
Anchor Studies2
Seizure detection based on heart rate variability using a wearable electrocardiography device.
Journal
Epilepsia · 2020
PMID
31538347
RCR
5.3
Citations
82
Study type
Clinical trial
Sample size
n = 100
adolescentadult
Seizure detection using heart rate variability: A prospective validation study.
Journal
Epilepsia · 2021
PMID
32378197
RCR
3.0
Citations
42
Study type
Clinical trial
adolescentadult
Supporting Studies1
A systematic review and meta-analysis of heart rate variability in epilepsy and antiepileptic drugs.
Journal
Epilepsia · 2012
PMID
22221253
RCR
9.6
Citations
223
Study type
Meta-analysis
anticonvulsantsarrhythmias, cardiac
Evidence on: Higher occupational stress is associated with lower heart rate variability.
6 scored
Anchor Studies2
Heart rate variability and occupational stress-systematic review.
Journal
Industrial health · 2019
PMID
29910218
RCR
10.9
Citations
143
Study type
Systematic review
Sample size
653 participants
autonomic nervous systemelectrocardiography
Continuous heart rate variability monitoring, stress and recovery in doctors: a systematic review and meta-analysis.
Journal
Occupational medicine (Oxford, England) · 2026
PMID
41157926
Citations
2
Study type
Meta-analysis
humansheart rate
Supporting Studies3
Heart rate variability as a measure of mental stress in surgery: a systematic review.
Journal
International archives of occupational and environmental health · 2021
PMID
32215713
RCR
4.7
Citations
48
Study type
Systematic review
general surgeryheart rate
Heart rate variability as a dynamic marker of surgeons' stress during vascular surgery.
Journal
BJS open · 2024
PMID
39270744
RCR
3.8
Citations
10
Study type
Primary study
humansheart rate
Work-related mental stress in confined tunnel construction environments: a field study with heart rate variability (HRV).
Journal
Ergonomics · 2026
PMID
40791132
Citations
1
Study type
Primary study
humansheart rate
Null-Result Studies1
Teachers' ambulatory heart rate variability as an outcome and moderating variable in the job demands-resources model.
Journal
Anxiety, stress, and coping · 2021
PMID
32228186
RCR
1.5
Citations
15
Study type
Primary study
Sample size
101 participants
Bears on
Core claim
adultburnout, professional
Evidence on: People with bipolar disorder have lower resting heart rate variability.
2 scored
Anchor Studies1
Heart rate variability in bipolar disorder: A systematic review and meta-analysis.
Journal
Neuroscience and biobehavioral reviews · 2017
PMID
27986468
RCR
4.6
Citations
85
Study type
Meta-analysis
Sample size
n = 1581
bipolar disordermajor depressive disorder
Supporting Studies1
Heart rate variability in bipolar disorder and borderline personality disorder: a clinical review.
Journal
Evidence-based mental health · 2018
PMID
29223951
RCR
2.0
Citations
31
Study type
Review
autonomic nervous systembipolar disorder
Evidence on: Cold water immersion after exercise accelerates parasympathetic reactivation as measured by heart rate variability.
1 scored
Anchor Studies1
Cold Water Immersion, Heart Rate Variability and Post-Exercise Recovery: A Systematic Review.
Journal
Physiotherapy research international : the journal for researchers and clinicians in physical therapy · 2025
PMID
39918163
Citations
4
Study type
Systematic review
humansheart rate
Evidence on: Heart rate variability analysis detects obstructive sleep apnea accurately enough to screen for it.
7 scored
Anchor Studies1
Electrocardiogram heart rate variability for machine learning diagnosis of obstructive sleep Apnoea: A bayesian meta-analysis.
Journal
Sleep & breathing = Schlaf & Atmung · 2025
PMID
41026252
Citations
4
Study type
Meta-analysis
Sample size
2,019 participants
humanssleep apnea, obstructive
Supporting Studies6
Detecting sleep apnea using non-linear measures of heart rate variability.
Journal
Respiratory research · 2026
PMID
41851735
Citations
1
Study type
Primary study
humansheart rate
Heart and Respiration Rate Variability Analysis to Estimate the Apnoea-Hypopnoea Index in People With Intellectual Disabilities.
Journal
Journal of intellectual disability research : JIDR · 2026
PMID
41531095
Citations
0
Study type
Primary study
Sample size
73 participants
humansintellectual disability
Heart Rate Variability in the Diagnostics and CPAP Treatment of Obstructive Sleep Apnea.
Journal
Advances in experimental medicine and biology · 2019
PMID
31073928
RCR
0.7
Citations
11
Study type
Primary study
Sample size
n = 15
autonomic nervous systemcase-control studies
Ultra-short term Heart Rate Variability in moderate and severe Obstructive Sleep Apnea.
Journal
Respiratory medicine · 2026
PMID
41580095
Citations
0
Study type
Primary study
Sample size
88 patients
humanssleep apnea, obstructive
Heart rate variability and obstructive sleep apnea: Current perspectives and novel technologies.
Journal
Journal of sleep research · 2021
PMID
33462936
RCR
6.6
Citations
72
Study type
Review
autonomic nervous systemheart rate
Validation of a Textile-Based Wearable Measuring Electrocardiogram and Breathing Frequency for Sleep Apnea Monitoring.
Journal
Sensors (Basel, Switzerland) · 2024
PMID
39409269
RCR
1.7
Citations
6
Study type
Primary study
humansmale
Evidence on: Heart rate variability changes measurably in response to cognitive workload.
6 scored
Anchor Studies2
Cardiac Measures of Cognitive Workload: A Meta-Analysis.
Journal
Human factors · 2020
PMID
30822151
RCR
4.2
Citations
48
Study type
Meta-analysis
cognitionheart rate
Heart rate dynamics for cognitive load estimation in a driving simulation task.
Journal
Scientific reports · 2024
PMID
39738154
RCR
5.3
Citations
12
Study type
Primary study
humansheart rate
Supporting Studies3
Heart Rate Variability and Body Motion as Digital Biomarkers of Task Workload During Military En Route Critical Care Simulations.
Journal
Sensors (Basel, Switzerland) · 2026
PMID
42281109
Citations
0
Study type
Primary study
humansheart rate
Workload Intensity in Human-Robot Collaboration: A Personalized Approach to Sustainable Efficiency and Well-Being.
Journal
Human factors · 2026
PMID
41671514
Citations
0
Study type
Primary study
humansworkload
Change in heart rate variability with increasing time-on-task as a marker for mental fatigue: A systematic review.
Journal
Biological psychology · 2024
PMID
38056707
RCR
10.9
Citations
28
Study type
Systematic review
humansautonomic nervous system
Null-Result Studies1
A well-powered test of task difficulty effects on cardiovascular indicators of mental effort.
Journal
International journal of psychophysiology : official journal of the International Organization of Psychophysiology · 2026
PMID
41951107
Citations
0
Study type
Primary study
Sample size
n = 114
Bears on
Core claim
humansfemale
Evidence on: Higher resting heart rate variability is associated with better self-control.
1 scored
Anchor Studies1
Heart rate variability and self-control--A meta-analysis.
Journal
Biological psychology · 2016
PMID
26747415
RCR
6.2
Citations
107
Study type
Meta-analysis
Sample size
n = 2317
arousalelectrocardiography
Evidence on: GLP-1 receptor agonists raise resting heart rate and lower heart rate variability.
5 scored
Anchor Studies2
Effects of Liraglutide on Heart Rate and Heart Rate Variability: A Randomized, Double-Blind, Placebo-Controlled Crossover Study.
Journal
Diabetes care · 2017
PMID
27797930
RCR
3.3
Citations
80
Study type
Randomized controlled trial
Sample size
27 subjects
agedcircadian rhythm
Heart rate acceleration with GLP-1 receptor agonists in type 2 diabetes patients: an acute and 12-week randomised, double-blind, placebo-controlled trial.
Journal
European journal of endocrinology · 2017
PMID
27777261
RCR
1.7
Citations
47
Study type
Randomized controlled trial
Sample size
n = 29
agedblood glucose
Supporting Studies3
Heart and health behavior responses to GLP-1 receptor agonists: a 12-wk study using wearable technology and causal inference.
Journal
American journal of physiology. Heart and circulatory physiology · 2025
PMID
39705534
RCR
2.4
Citations
8
Study type
Primary study
Sample size
66 individuals
humansmale
Exenatide acutely increases heart rate in parallel with augmented sympathetic nervous system activation in healthy overweight males.
Journal
British journal of clinical pharmacology · 2016
PMID
26609792
RCR
2.0
Citations
56
Study type
Clinical trial
adultblood glucose
GLP-1 receptor stimulation depresses heart rate variability and inhibits neurotransmission to cardiac vagal neurons.
Journal
Cardiovascular research · 2011
PMID
20736238
RCR
2.8
Citations
92
Study type
Primary study
animalsexenatide
Evidence on: The Oura Ring measures overnight heart rate variability in close agreement with an ECG reference.
5 scored
Anchor Studies4
Validation of nocturnal resting heart rate and heart rate variability in consumer wearables.
Journal
Physiological reports · 2025
PMID
40834291
RCR
3.7
Citations
10
Study type
Validity study
humansheart rate
Accuracy Assessment of Oura Ring Nocturnal Heart Rate and Heart Rate Variability in Comparison With Electrocardiography in Time and Frequency Domains: Comprehensive Analysis
Journal
Journal of Medical Internet Research · 2022
DOI
10.2196/27487
Citations
158
Feasible assessment of recovery and cardiovascular health: accuracy of nocturnal HR and HRV assessed via ring PPG in comparison to medical grade ECG.
Journal
Physiological measurement · 2020
PMID
32217820
RCR
10.2
Citations
121
Study type
Comparative study
adolescentadult
Deriving Accurate Nocturnal Heart Rate, rMSSD and Frequency HRV from the Oura Ring.
Journal
Sensors (Basel, Switzerland) · 2024
PMID
39686012
RCR
2.6
Citations
8
Study type
Primary study
humansheart rate
Supporting Studies1
Assessing the Accuracy of Popular Commercial Technologies That Measure Resting Heart Rate and Heart Rate Variability
Journal
Frontiers in Sports and Active Living · 2021
DOI
10.3389/fspor.2021.585870
Citations
97
Evidence on: Apple Watch measures heart rate variability in close agreement with an ECG or chest-strap reference.
4 scored
Anchor Studies2
The Validity of Apple Watch Series 9 and Ultra 2 for Serial Measurements of Heart Rate Variability and Resting Heart Rate.
Journal
Sensors (Basel, Switzerland) · 2024
PMID
39409260
RCR
5.9
Citations
16
Study type
Primary study
humansheart rate
Validity of Heart Rate Variability Measured with Apple Watch Series 6 Compared to Laboratory Measures.
Journal
Sensors (Basel, Switzerland) · 2025
PMID
40285070
RCR
3.7
Citations
9
Study type
Primary study
Sample size
n = 78
wearable electronic devicesheart rate determination
Supporting Studies2
Validation of the Apple Watch for Heart Rate Variability Measurements during Relax and Mental Stress in Healthy Subjects.
Journal
Sensors (Basel, Switzerland) · 2018
PMID
30103376
RCR
8.4
Citations
127
Study type
Validity study
autonomic nervous systemhealthy volunteers
Estimation of Heart Rate Variability Measures Using Apple Watch and Evaluating Their Accuracy
Journal
PErvasive Technologies Related to Assistive Environments Conference (PETRA) · 2021
DOI
10.1145/3453892.3462647
Citations
7
01 Research Log
JUL 9 2026
Comparative analysis of heart rate variability indices from ballistocardiogram and electrocardiogram: a study on measurement agreement. (Heart and vessels 2025) entered as supporting on the measurement validity claim.
Kubios HRV--heart rate variability analysis software. (Computer methods and programs in biomedicine 2014) entered as supporting on the measurement validity claim.
Effects of electrocardiographic noise on ultra-short term Heart Rate Variability indices. (Computers in biology and medicine 2025) entered as supporting on the measurement validity claim.
Reference values for time- and frequency-domain heart rate variability measures. (Heart rhythm 2018) entered as supporting on the measurement validity claim.
The reliability of short-term measurements of heart rate variability. (International journal of cardiology 2005) entered as conflicting on the measurement validity claim.
Test-retest reliability of time- and frequency-domain measures of short-term resting heart rate variability in a healthy young population. (International journal of psychophysiology : official journal of the International Organization of Psychophysiology 2026) entered as supporting on the measurement validity claim.
Intra-day and inter-day reliability of heart rate variability measurement. (Journal of sports sciences 2013) entered as supporting on the measurement validity claim.
Reliability of resting-state photoplethysmogram-based pulse rate variability in lifespan samples: implications for cardiovascular research. (Physiological measurement 2026) entered as supporting on the measurement validity claim.
A quantitative systematic review of normal values for short-term heart rate variability in healthy adults. (Pacing and clinical electrophysiology : PACE 2011) entered as supporting on the measurement validity claim.
Publication guidelines for human heart rate and heart rate variability studies in psychophysiology-Part 1: Physiological underpinnings and foundations of measurement. (Psychophysiology 2024) entered as anchor on the measurement validity claim.
Limited Validity of the Low-Cost Coospo H808S Heart-Rate Monitor Compared to the Polar H10. (International journal of sports physiology and performance 2025) entered as anchor on the measurement validity claim.
Validation of nocturnal resting heart rate and heart rate variability in consumer wearables. (Physiological reports 2025) entered as anchor on the measurement validity claim.
Optimizing Intersession Reliability of Heart Rate Variability-The Effects of Artifact Correction and Breathing Type. (Journal of strength and conditioning research 2021) entered as supporting on the measurement validity claim.
Can Wearable Devices Accurately Measure Heart Rate Variability? A Systematic Review. (Folia medica 2019) entered as anchor on the measurement validity claim.
The Validity of Apple Watch Series 9 and Ultra 2 for Serial Measurements of Heart Rate Variability and Resting Heart Rate. (Sensors (Basel, Switzerland) 2024) entered as anchor on the measurement validity claim.
Deriving Accurate Nocturnal Heart Rate, rMSSD and Frequency HRV from the Oura Ring. (Sensors (Basel, Switzerland) 2024) entered as anchor on the measurement validity claim.
A Comparative Study Between ECG- and PPG-Based Heart Rate Sensors for Heart Rate Variability Measurements: Influence of Body Position, Duration, Sex, and Age. (Sensors (Basel, Switzerland) 2025) entered as anchor on the measurement validity claim.
Butterworth Filtering at 500 Hz Optimizes PPG-Based Heart Rate Variability Analysis for Wearable Devices: A Comparative Study. (Sensors (Basel, Switzerland) 2025) entered as supporting on the measurement validity claim.
Signal Quality Assessment and Reconstruction of PPG-Derived Signals for Heart Rate and Variability Estimation in In-Vehicle Applications: A Comparative Review and Empirical Validation. (Sensors (Basel, Switzerland) 2025) entered as conflicting on the measurement validity claim.
Heart rate variability and autonomic activity at rest and during exercise in various physiological conditions. (European journal of applied physiology 2004) entered as supporting on the physiological claim.
Heart Rate Variability Applications in Medical Specialties: A Narrative Review. (Applied psychophysiology and biofeedback 2025) entered as supporting on the physiological claim.
Heart rate variability: a review. (Medical & biological engineering & computing 2007) entered as supporting on the physiological claim.
Heart rate variability. (Handbook of clinical neurology 2014) entered as supporting on the physiological claim.
The relationship of autonomic imbalance, heart rate variability and cardiovascular disease risk factors. (International journal of cardiology 2010) entered as anchor on the physiological claim.
Heart rate variability today. (Progress in cardiovascular diseases 2013) entered as supporting on the physiological claim.
Determinants of heart rate variability. (Journal of the American College of Cardiology 1996) entered as anchor on the physiological claim.
Fractal analysis of heart rate variability as a predictor of mortality: A systematic review and meta-analysis. (Chaos (Woodbury, N.Y.) 2018) entered as anchor on the physiological claim.
Interaction between heart rate and heart rate variability. (Annals of noninvasive electrocardiology : the official journal of the International Society for Holter and Noninvasive Electrocardiology, Inc 2014) entered as supporting on the physiological claim.
Heart rate variability coefficient of variation during sleep as a digital biomarker that reflects behavior and varies by age and sex. (American journal of physiology. Heart and circulatory physiology 2026) entered as supporting on the physiological claim.
Heart Rate Variability and Risk of All-Cause Death and Cardiovascular Events in Patients With Cardiovascular Disease: A Meta-Analysis of Cohort Studies. (Biological research for nursing 2020) entered as anchor on the physiological claim.
Heart rate variability as predictive factor for sudden cardiac death. (Aging 2019) entered as anchor on the physiological claim.
Associations Between Daily Heart Rate Variability and Self-Reported Wellness: A 14-Day Observational Study in Healthy Adults. (Sensors (Basel, Switzerland) 2025) entered as supporting on the physiological claim.
Resting Heart Rate Variability Measured by Consumer Wearables and Its Associations with Diverse Health Domains in Five Longitudinal Studies. (Sensors (Basel, Switzerland) 2025) entered as supporting on the physiological claim.
Disconnection Between Self-Reported Wellbeing and Heart Rate Variability from Wearables. (Sensors (Basel, Switzerland) 2026) entered as null_result on the physiological claim.
Heart rate variability in health and disease. (Scandinavian journal of work, environment & health 1995) entered as supporting on the physiological claim.
Heart rate variability over the decades: a scoping review. (PeerJ 2025) entered as supporting on the physiological claim.
Heart rate variability. Frequency domain analysis. (Cardiology clinics 1992) entered as supporting on the physiological claim.
JUL 9 2026
The reliability of short-term measurements of heart rate variability. (International journal of cardiology 2005) entered as a conflicting study on the measurement validity claim, bearing on the core claim.
It caps the rating until reconciled.
JUL 9 2026
Signal Quality Assessment and Reconstruction of PPG-Derived Signals for Heart Rate and Variability Estimation in In-Vehicle Applications: A Comparative Review and Empirical Validation. (Sensors (Basel, Switzerland) 2025) entered as a conflicting study on the measurement validity claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
JUL 9 2026
Disconnection Between Self-Reported Wellbeing and Heart Rate Variability from Wearables. (Sensors (Basel, Switzerland) 2026) entered as a null result study on the physiological claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
JUL 11 2026
Determinants of heart rate variability in the general population: The Lifelines Cohort Study. (Heart rhythm 2019) entered as anchor on the physiological claim.
Heart rate variability as a biomarker for transdiagnostic depressive and anxiety symptom trajectory in adolescents and young adults. (Journal of psychopathology and clinical science 2024) entered as supporting on the physiological claim.
Heart Rate Variability and Risk of All-Cause Death and Cardiovascular Events in Patients With Cardiovascular Disease: A Meta-Analysis of Cohort Studies. (Biological research for nursing 2020) entered as anchor on the physiological claim.
The Association between Neuroticism and Heart Rate Variability Is Not Fully Explained by Cardiovascular Disease and Depression. (PloS one 2016) entered as supporting on the physiological claim.
State Anxiety and Nonlinear Dynamics of Heart Rate Variability in Students. (PloS one 2016) entered as supporting on the physiological claim.
Heart rate variability as predictive factor for sudden cardiac death. (Aging 2019) entered as supporting on the physiological claim.
JUL 11 2026
Neuroticism and extraversion in relation to physiological stress reactivity during adolescence. (Biological psychology 2017) entered as supporting on the trait neuroticism claim.
Association of negative affect with resting heart rate variability in medical students. (Biological psychology 2025) entered as null_result on the trait neuroticism claim.
Determinants of heart rate variability in the general population: The Lifelines Cohort Study. (Heart rhythm 2019) entered as anchor on the trait neuroticism claim.
Decreased heart rate variability during emotion regulation in subjects at risk for psychopathology. (Psychological medicine 2012) entered as supporting on the trait neuroticism claim.
Neuroticism's importance in understanding the daily life correlates of heart rate variability. (Emotion (Washington, D.C.) 2010) entered as supporting on the trait neuroticism claim.
Measures of the psychophysiological response to recurrent anticipatory stress - the influence of neuroticism on heart rhythm and skin resistance. (Scientific reports 2026) entered as supporting on the trait neuroticism claim.
The Association between Neuroticism and Heart Rate Variability Is Not Fully Explained by Cardiovascular Disease and Depression. (PloS one 2016) entered as anchor on the trait neuroticism claim.
Relationship between neuroticism, threat of shock and heart rate variability reactivity. (International maritime health 2014) entered as supporting on the trait neuroticism claim.
JUL 11 2026
Association of negative affect with resting heart rate variability in medical students. (Biological psychology 2025) entered as a null result study on the trait neuroticism claim, bearing on the core claim.
It caps the rating until reconciled.
JUL 17 2026
Theories of Arousal Predict a Link Between Heart Rate Variability and Reactive Aggression: Meta-Analytic Results Disagree. (Aggressive behavior 2024) entered as null_result on the physiological claim.
JUL 17 2026
Theories of Arousal Predict a Link Between Heart Rate Variability and Reactive Aggression: Meta-Analytic Results Disagree. (Aggressive behavior 2024) entered as a null result study on the physiological claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
JUL 17 2026
The relationship of autonomic imbalance, heart rate variability and cardiovascular disease risk factors. (International journal of cardiology 2010) entered as anchor on the physiological claim.
AUG 7 2026
Validation of nocturnal resting heart rate and heart rate variability in consumer wearables. (Physiological reports 2025) entered as anchor on the measurement validity claim.
The relationship of autonomic imbalance, heart rate variability and cardiovascular disease risk factors. (International journal of cardiology 2010) entered as anchor on the physiological claim.
Your partner makes a difference. Affective touch delivered by the romantic partner improves affective state but not physiological state. (International journal of psychophysiology : official journal of the International Organization of Psychophysiology 2026) entered as supporting on the physiological claim.
New insights in heart rate variability through non-linear methods for conditioning assessment in horses. (Veterinary journal (London, England : 1997) 2026) entered as supporting on the physiological claim.
Fractal analysis of heart rate variability as a predictor of mortality: A systematic review and meta-analysis. (Chaos (Woodbury, N.Y.) 2018) entered as anchor on the physiological claim.
Heart Rate Variability and Risk of All-Cause Death and Cardiovascular Events in Patients With Cardiovascular Disease: A Meta-Analysis of Cohort Studies. (Biological research for nursing 2020) entered as anchor on the physiological claim.
AUG 14 2026
Theories of Arousal Predict a Link Between Heart Rate Variability and Reactive Aggression: Meta-Analytic Results Disagree. (Aggressive behavior 2024) entered as null_result on the physiological claim.
AUG 14 2026
Theories of Arousal Predict a Link Between Heart Rate Variability and Reactive Aggression: Meta-Analytic Results Disagree. (Aggressive behavior 2024) entered as a null result study on the physiological claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
AUG 21 2026
Reproducibility of 24-h heart rate variability in children. (Clinical autonomic research : official journal of the Clinical Autonomic Research Society 2018) entered as supporting on the measurement validity claim.
Validation of the ultra short term heart rate variability measures under changing psychophysiological state of the healthy participants at rest. (Scientific reports 2026) entered as supporting on the measurement validity claim.
Evaluation of HRV-PRV agreement with autoencoder-based signal quality assessment in resting and dynamic conditions. (Physiological measurement 2026) entered as supporting on the measurement validity claim.
Heart Rate Variability Analysis on CEBS Database Signals. (Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference 2019) entered as supporting on the measurement validity claim.
The Novel Estimation Algorithm of Heart Rate Variability and Stress Using Facial Video Analysis. (Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference 2025) entered as supporting on the measurement validity claim.
Hybrid CNN-LSTM Model for Evaluating Heart Rate Variability from Pulse-to-Pulse Intervals. (Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference 2025) entered as supporting on the measurement validity claim.
Validity and reliability of short-term heart-rate variability from the Polar S810. (Medicine and science in sports and exercise 2009) entered as supporting on the measurement validity claim.
doi:10.1002/(sici)1096-8628(19990402)83:4<296::aid-ajmg11>3.0.co;2-d entered as supporting on the physiological claim.
Infant emotion regulation in the context of stress: Effects of heart rate variability and temperament. (Stress and health : journal of the International Society for the Investigation of Stress 2024) entered as supporting on the physiological claim.
Heart rate variability (HRV) and posttraumatic stress disorder (PTSD): a pilot study. (Applied psychophysiology and biofeedback 2011) entered as supporting on the physiological claim.
Effects of stress management interventions on heart rate variability in adults with cardiovascular disease: a systematic review and meta-analysis. (Journal of behavioral medicine 2024) entered as supporting on the physiological claim.
Heart rate variability predicts alcohol craving in alcohol dependent outpatients: further evidence for HRV as a psychophysiological marker of self-regulation. (Drug and alcohol dependence 2014) entered as supporting on the physiological claim.
Nighttime heart rate variability, overnight urinary norepinephrine, and glycemic status in apparently healthy human adults. (International journal of cardiology 2014) entered as supporting on the physiological claim.
Indicators of heart rate variability, urinary norepinephrine and plasma lipid levels in healthy adults. (International journal of cardiology 2014) entered as supporting on the physiological claim.
Heart rate variability, but not heart rate, is associated with handgrip strength and mortality in older Africans at very low cardiovascular risk: A population-based study. (International journal of cardiology 2016) entered as supporting on the physiological claim.
Identifying high-risk post-infarction patients by autonomic testing - Below the tip of the iceberg. (International journal of cardiology 2018) entered as supporting on the physiological claim.
Genetic influences on heart rate variability. (International journal of psychophysiology : official journal of the International Organization of Psychophysiology 2017) entered as supporting on the physiological claim.
The Role of Heart Rate Variability in Mindfulness-Based Pain Relief. (The journal of pain 2021) entered as supporting on the physiological claim.
A pattern-based heart rate variability approach in somatic symptom disorder: Evidence from the SOMA.SSD study. (Journal of psychosomatic research 2026) entered as supporting on the physiological claim.
Sex differences in regulatory mechanisms of the cardiovascular system during simulated hypokinesia. (Life sciences in space research 2026) entered as supporting on the physiological claim.
Heart rate variability analysis in patients with multiple sclerosis. (Multiple sclerosis and related disorders 2018) entered as supporting on the physiological claim.
Clinical applicability of heart rate variability analysis by methods based on nonlinear dynamics. (Cardiac electrophysiology review 2003) entered as supporting on the physiological claim.
Heart rate variability and emotion regulation: Multiethnic differences in reappraisal and suppression. (Emotion (Washington, D.C.) 2026) entered as supporting on the physiological claim.
Differential associations of resting heart rate and heart rate variability indices with cardiovascular and coronary heart disease mortality risk: the prospective KORA study. (Scientific reports 2026) entered as anchor on the physiological claim.
Overnight Heart Rate Variability During Sleep Disturbance In Peri- And Postmenopausal Women. (Behavioral sleep medicine 2025) entered as supporting on the physiological claim.
Altered heart rate variability is associated with all-cause mortality in patients with co-morbid insomnia and obstructive sleep apnea. (Sleep 2026) entered as anchor on the physiological claim.
Heart rate variability in acute psychosis. (Psychophysiology 2004) entered as supporting on the physiological claim.
Arrhythmia, heart rate variability, and antiepileptic drugs. (Epilepsia 2010) entered as supporting on the physiological claim.
Heart rate variability in healthy subjects: effect of age and derivation of normal ranges for tests of autonomic function. (British heart journal 1987) entered as supporting on the physiological claim.
Heart-rate variability in sleep and wakefulness. (Cardiology 1971) entered as supporting on the physiological claim.
Smartwatch-derived exercise metrics as predictors of early hypertension: a prospective observational study. (BMC cardiovascular disorders 2026) entered as supporting on the physiological claim.
Heart Rate Variability and Blood Pressure Response to Low-Intensity Endurance Exercise Training Plus Blood Flow Restriction in Individuals with Mild Hypertension: A Randomized Controlled Clinical Trial. (Iranian journal of medical sciences 2025) entered as supporting on the physiological claim.
TSH index and 24-hour mean heart rate in euthyroid adults: opposing FT3 and heart rate variability components. (Frontiers in endocrinology 2026) entered as supporting on the physiological claim.
Heart rate variability in epilepsy and its association with disease duration: a retrospective case-control study. (Frontiers in neurology 2026) entered as supporting on the physiological claim.
Heart rate variability and sleep. (Circulation 1996) entered as supporting on the physiological claim.
SEP 4 2026
Validity of the Polar H7 Heart Rate Sensor for Heart Rate Variability Analysis during Exercise in Different Age, Body Composition and Fitness Level Groups. (Sensors (Basel, Switzerland) 2021) entered as supporting on the measurement validity claim.
Heart rate variability as a predictor of mortality in patients with AA and AL amyloidosis. (European heart journal 2002) entered as supporting on the physiological claim.
Heart Rate Variability Predicts Major Adverse Cardiovascular Events and Hospitalization in Maintenance Hemodialysis Patients. (Kidney & blood pressure research 2018) entered as supporting on the physiological claim.
Role of Heart Rate Variability in Association Between Glomerular Hyperfiltration and All-Cause Mortality. (Journal of the American Heart Association 2022) entered as supporting on the physiological claim.
Impedance cardiography and heart rate variability for long-term cardiovascular outcome prediction after myocardial infarction. (Medicina (Kaunas, Lithuania) 2013) entered as supporting on the physiological claim.
SEP 17 2026
Publication guidelines for human heart rate and heart rate variability studies in psychophysiology-Part 1: Physiological underpinnings and foundations of measurement. (Psychophysiology 2024) entered as anchor on the measurement validity claim.
Validity of Heart Rate Variability Measured with Apple Watch Series 6 Compared to Laboratory Measures. (Sensors (Basel, Switzerland) 2025) entered as supporting on the measurement validity claim.
Heart rate variability analysis in patients with multiple sclerosis. (Multiple sclerosis and related disorders 2018) entered as supporting on the physiological claim.
Posttraumatic stress, heart rate variability, and the mediating role of behavioral health risks. (Psychosomatic medicine 2015) entered as supporting on the physiological claim.
Procedural memory consolidation is associated with heart rate variability and sleep spindles. (Journal of sleep research 2021) entered as supporting on the physiological claim.
Heart rate variability during night sleep and after awakening in overtrained athletes. (Medicine and science in sports and exercise 2006) entered as supporting on the physiological claim.
The subjective sleep quality and heart rate variability in hemodialysis patients. (Renal failure 2011) entered as supporting on the physiological claim.
SEP 29 2026
Heart rate variability: reference values and role for clinical profile and mortality in individuals with heart failure. (Clinical research in cardiology : official journal of the German Cardiac Society 2024) entered as supporting on the normal range age claim.
Comprehensive linear and nonlinear heart rate variability normative data in children. (Clinical autonomic research : official journal of the Clinical Autonomic Research Society 2025) entered as supporting on the normal range age claim.
Reference values for time- and frequency-domain heart rate variability measures. (Heart rhythm 2018) entered as anchor on the normal range age claim.
Effect of age and sex on heart rate variability in healthy subjects. (Journal of manipulative and physiological therapeutics 2007) entered as anchor on the normal range age claim.
A quantitative systematic review of normal values for short-term heart rate variability in healthy adults. (Pacing and clinical electrophysiology : PACE 2011) entered as anchor on the normal range age claim.
SEP 29 2026
Detection of COVID-19 using multimodal data from a wearable device: results from the first TemPredict Study. (Scientific reports 2022) entered as supporting on the acute drop infection claim.
Real-time infection prediction with wearable physiological monitoring and AI to aid military workforce readiness during COVID-19. (Scientific reports 2022) entered as supporting on the acute drop infection claim.
Heart rate variability in female soccer players, before, during, and after a COVID-19 positive test. (Scientific reports 2025) entered as anchor on the acute drop infection claim.
Day-to-day reliability of basal heart rate and short-term and ultra short-term heart rate variability assessment by the Equivital eq02+ LifeMonitor in US Army soldiers. (BMJ military health 2025) entered as supporting on the acute drop infection claim.
Using Patient-Held Devices to Measure Variations in Resting Heart Rate and Step Count Prior to Presentation With an Acute Illness: International, Multicenter Flash Mob Feasibility Study. (JMIR cardio 2025) entered as supporting on the acute drop infection claim.
SEP 29 2026
The level of acute alcohol exposure during binge drinking associates with the extent of cardiac response. (Clinical research in cardiology : official journal of the German Cardiac Society 2026) entered as supporting on the alcohol claim.
Heart rate variability in alcohol use: A review. (Pharmacology, biochemistry, and behavior 2020) entered as anchor on the alcohol claim.
Acute alcohol consumption and arrhythmias in young adults: the MunichBREW II study. (European heart journal 2024) entered as anchor on the alcohol claim.
Characteristics of heart rate variability in alcohol-dependent subjects and nondependent chronic alcohol users. (Alcoholism, clinical and experimental research 2014) entered as supporting on the alcohol claim.
SEP 29 2026
Exercise Frequency Determines Heart Rate Variability Gains in Older People: A Meta-Analysis and Meta-Regression. (Sports medicine (Auckland, N.Z.) 2020) entered as supporting on the exercise training claim.
The effect of exercise training on heart rate variability in patients with hypertension: A systematic review and meta-analysis. (Journal of sports sciences 2024) entered as anchor on the exercise training claim.
Beneficial impacts of physical activity on heart rate variability: A systematic review and meta-analysis. (PloS one 2024) entered as anchor on the exercise training claim.
SEP 29 2026
Physical activity, mindfulness meditation, or heart rate variability biofeedback for stress reduction: a randomized controlled trial. (Applied psychophysiology and biofeedback 2016) entered as supporting on the biofeedback anxiety claim.
Effects of Heart Rate Variability Biofeedback Training on Anxiety Reduction and Brain Activity: a Randomized Active-Controlled Study Using EEG. (Applied psychophysiology and biofeedback 2024) entered as null_result on the biofeedback anxiety claim.
A Randomized Sham-Controlled Trial of Heart Rate Variability Biofeedback Following Traumatic Brain Injury (TBI). (Applied psychophysiology and biofeedback 2026) entered as null_result on the biofeedback anxiety claim.
Psychophysiological effects of heart rate variability biofeedback versus sham biofeedback: A randomized controlled trial. (Biological psychology 2026) entered as anchor on the biofeedback anxiety claim.
Impact of a brief HRV-biofeedback intervention on emotion regulation following a real-life stressful event: A randomized controlled study. (Behaviour research and therapy 2026) entered as supporting on the biofeedback anxiety claim.
The effect of heart rate variability biofeedback training on stress and anxiety: a meta-analysis. (Psychological medicine 2018) entered as anchor on the biofeedback anxiety claim.
SEP 29 2026
Effects of Heart Rate Variability Biofeedback Training on Anxiety Reduction and Brain Activity: a Randomized Active-Controlled Study Using EEG. (Applied psychophysiology and biofeedback 2024) entered as a null result study on the biofeedback anxiety claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 29 2026
A Randomized Sham-Controlled Trial of Heart Rate Variability Biofeedback Following Traumatic Brain Injury (TBI). (Applied psychophysiology and biofeedback 2026) entered as a null result study on the biofeedback anxiety claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 29 2026
Efficacy of Paced Breathing at the Low-frequency Peak on Heart Rate Variability and Baroreflex Sensitivity. (Applied psychophysiology and biofeedback 2020) entered as supporting on the slow breathing claim.
Heart Rate and Breathing Are Not Always in Phase During Resonance Frequency Breathing. (Applied psychophysiology and biofeedback 2020) entered as supporting on the slow breathing claim.
Breathing slower is not always better: Slow-paced breathing enhances heart rate variability but produces age-differential effects on emotional reactivity and memory. (International journal of psychophysiology : official journal of the International Organization of Psychophysiology 2026) entered as null_result on the slow breathing claim.
Comparison of slow-paced breathing interventions with and without an inhalation-hold on physiological outcomes: A randomized cross-over pilot study. (International journal of psychophysiology : official journal of the International Organization of Psychophysiology 2026) entered as conflicting on the slow breathing claim.
Effect of Resonance Breathing on Heart Rate Variability and Cognitive Functions in Young Adults: A Randomised Controlled Study. (Cureus 2022) entered as anchor on the slow breathing claim.
SEP 29 2026
Breathing slower is not always better: Slow-paced breathing enhances heart rate variability but produces age-differential effects on emotional reactivity and memory. (International journal of psychophysiology : official journal of the International Organization of Psychophysiology 2026) entered as a null result study on the slow breathing claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 29 2026
Comparison of slow-paced breathing interventions with and without an inhalation-hold on physiological outcomes: A randomized cross-over pilot study. (International journal of psychophysiology : official journal of the International Organization of Psychophysiology 2026) entered as a conflicting study on the slow breathing claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
SEP 29 2026
Heart Rate Variability Biofeedback for Substance Use Disorder: A Randomized Clinical Trial. (JAMA psychiatry 2025) entered as anchor on the biofeedback cravings claim.
Theoretical implications and clinical support for heart rate variability biofeedback for substance use disorders. (Current opinion in psychology 2020) entered as supporting on the biofeedback cravings claim.
SEP 29 2026
Usefulness of heart rate variability indices in assessing the risk of an unsuccessful return to work after sick leave in depressed patients. (Neuropsychopharmacology reports 2021) entered as supporting on the depression claim.
Divergence of clinical and autonomic recovery in adolescent major depressive disorder: A 10-week prospective heart rate variability study with nocturnal electrocardiogram monitoring. (Journal of affective disorders 2026) entered as anchor on the depression claim.
The role of change in peripartum heart rate variability in the prediction of depressive symptoms 18 months after childbirth: a follow-up study. (Journal of psychiatric research 2026) entered as supporting on the depression claim.
A meta-analysis of heart rate variability and psychopathology: An investigation guided by the hierarchical taxonomy of psychopathology framework. (Journal of psychopathology and clinical science 2026) entered as anchor on the depression claim.
Heart rate variability as a biomarker for transdiagnostic depressive and anxiety symptom trajectory in adolescents and young adults. (Journal of psychopathology and clinical science 2024) entered as conflicting on the depression claim.
Heart Rate Variability, Sleep Quality, and Depression in the Context of Chronic Stress. (Annals of behavioral medicine : a publication of the Society of Behavioral Medicine 2021) entered as supporting on the depression claim.
Heart and soul: heart rate variability and major depression. (Behavioural pharmacology 2019) entered as supporting on the depression claim.
Autonomic dysfunction and heart rate variability in depression. (Stress (Amsterdam, Netherlands) 2016) entered as supporting on the depression claim.
SEP 29 2026
Heart rate variability as a biomarker for transdiagnostic depressive and anxiety symptom trajectory in adolescents and young adults. (Journal of psychopathology and clinical science 2024) entered as a conflicting study on the depression claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
SEP 29 2026
The role of perseverative cognition and heart rate variability in high trait anxiety. (International journal of psychophysiology : official journal of the International Organization of Psychophysiology 2025) entered as supporting on the anxiety claim.
Altered autonomic stress reactivity and recovery in panic disorder during the Trier Social Stress Test. (Journal of affective disorders 2026) entered as anchor on the anxiety claim.
A meta-analysis of heart rate variability and psychopathology: An investigation guided by the hierarchical taxonomy of psychopathology framework. (Journal of psychopathology and clinical science 2026) entered as anchor on the anxiety claim.
Heart Rate Variability Moderates the Association Between Trait Anxiety and Sympathetic Nerve Activity in Humans. (Hypertension (Dallas, Tex. : 1979) 2026) entered as supporting on the anxiety claim.
How Much Does Stress Cost? A Case-Control Study on Vagally Mediated Heart Rate Variability Responses in Anxious and Non-Anxious Individuals During a Cognitive Task. (Medical sciences (Basel, Switzerland) 2025) entered as anchor on the anxiety claim.
SEP 29 2026
The Effects of Antidepressants and Quetiapine on Heart Rate Variability. (Pharmacopsychiatry 2017) entered as null_result on the antidepressants claim.
Heart rate variability during antidepressant treatment with venlafaxine and mirtazapine. (Clinical neuropharmacology 2014) entered as anchor on the antidepressants claim.
SEP 29 2026
The Effects of Antidepressants and Quetiapine on Heart Rate Variability. (Pharmacopsychiatry 2017) entered as a null result study on the antidepressants claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 29 2026
Theories of Arousal Predict a Link Between Heart Rate Variability and Reactive Aggression: Meta-Analytic Results Disagree. (Aggressive behavior 2024) entered as null_result on the reactive aggression claim.
SEP 29 2026
Theories of Arousal Predict a Link Between Heart Rate Variability and Reactive Aggression: Meta-Analytic Results Disagree. (Aggressive behavior 2024) entered as a null result study on the reactive aggression claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 29 2026
Acute effects of oral delta-9-tetrahydrocannabinol (THC) on autonomic cardiac activity and their relation to subjective and anxiogenic effects. (Psychophysiology 2022) entered as anchor on the cannabis claim.
SEP 29 2026
Heart rate variability, electrodermal activity and cognition in adults: Association with short-term indoor PM2.5 exposure in a real-world intervention study. (Environmental research 2024) entered as anchor on the air quality claim.
SEP 29 2026
Wearable-measured heart rate variability and premenstrual disorder symptoms across menstrual cycle. (Archives of women's mental health 2026) entered as anchor on the menstrual cycle claim.
Cardiac autonomic regulation across the menstrual cycle is highly individual: evidence from phase-aligned cyclic generalized additive mixed models. (American journal of physiology. Regulatory, integrative and comparative physiology 2026) entered as null_result on the menstrual cycle claim.
Variations in Estrogen, Progesterone, and Nocturnal Physiology are not Associated with Performance and Sleep within and between Menstrual Cycles. (Medicine and science in sports and exercise 2026) entered as conflicting on the menstrual cycle claim.
SEP 29 2026
Cardiac autonomic regulation across the menstrual cycle is highly individual: evidence from phase-aligned cyclic generalized additive mixed models. (American journal of physiology. Regulatory, integrative and comparative physiology 2026) entered as a null result study on the menstrual cycle claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 29 2026
Variations in Estrogen, Progesterone, and Nocturnal Physiology are not Associated with Performance and Sleep within and between Menstrual Cycles. (Medicine and science in sports and exercise 2026) entered as a conflicting study on the menstrual cycle claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
SEP 29 2026
Effect of atenolol versus ivabradine on heart rate variability in patients of schizophrenia with clozapine-induced tachycardia: a randomized controlled trial. (Psychiatry research 2026) entered as conflicting on the beta blockers claim.
Effects of low-dose metoprolol succinate sustained-release tablets on patients with paroxysmal atrial fibrillation undergoing circumferential pulmonary vein isolation: a retrospective cohort study. (BMC cardiovascular disorders 2025) entered as null_result on the beta blockers claim.
Effect of propranolol on heart rate variability in hyperthyroidism. (BMC research notes 2018) entered as null_result on the beta blockers claim.
SEP 29 2026
Effect of atenolol versus ivabradine on heart rate variability in patients of schizophrenia with clozapine-induced tachycardia: a randomized controlled trial. (Psychiatry research 2026) entered as a conflicting study on the beta blockers claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 29 2026
Effects of low-dose metoprolol succinate sustained-release tablets on patients with paroxysmal atrial fibrillation undergoing circumferential pulmonary vein isolation: a retrospective cohort study. (BMC cardiovascular disorders 2025) entered as a null result study on the beta blockers claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 29 2026
Effect of propranolol on heart rate variability in hyperthyroidism. (BMC research notes 2018) entered as a null result study on the beta blockers claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 29 2026
Validity of the Polar H10 for heart rate variability and cardiac autonomic reflex tests. (Autonomic neuroscience : basic & clinical 2026) entered as anchor on the chest strap accuracy claim.
Limited Validity of the Low-Cost Coospo H808S Heart-Rate Monitor Compared to the Polar H10. (International journal of sports physiology and performance 2025) entered as supporting on the chest strap accuracy claim.
Can Wearable Devices Accurately Measure Heart Rate Variability? A Systematic Review. (Folia medica 2019) entered as supporting on the chest strap accuracy claim.
Validity of the Polar H7 Heart Rate Sensor for Heart Rate Variability Analysis during Exercise in Different Age, Body Composition and Fitness Level Groups. (Sensors (Basel, Switzerland) 2021) entered as anchor on the chest strap accuracy claim.
SEP 29 2026
Ultra-short heart rate variability recording reliability: The effect of controlled paced breathing. (Annals of noninvasive electrocardiology : the official journal of the International Society for Holter and Noninvasive Electrocardiology, Inc 2019) entered as anchor on the measurement duration claim.
Validity of Smartphone Heart Rate Variability Pre- and Post-Resistance Exercise. (Sensors (Basel, Switzerland) 2021) entered as conflicting on the measurement duration claim.
Short-term heart rate variability in resting conditions: methodological considerations. (Kardiologia polska 2021) entered as supporting on the measurement duration claim.
SEP 29 2026
Validity of Smartphone Heart Rate Variability Pre- and Post-Resistance Exercise. (Sensors (Basel, Switzerland) 2021) entered as a conflicting study on the measurement duration claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
SEP 29 2026
Heart rate variability: reference values and role for clinical profile and mortality in individuals with heart failure. (Clinical research in cardiology : official journal of the German Cardiac Society 2024) entered as supporting on the prognostic in cardiac disease claim.
Heart Rate Variability Triangular Index as a Predictor of Cardiovascular Mortality in Patients With Atrial Fibrillation. (Journal of the American Heart Association 2021) entered as supporting on the prognostic in cardiac disease claim.
Heart rate variability as predictive factor for sudden cardiac death. (Aging 2019) entered as anchor on the prognostic in cardiac disease claim.
SEP 29 2026
Heart rate variability wrist-wearable biomarkers identify adverse posttraumatic neuropsychiatric sequelae after traumatic stress exposure. (Psychiatry research 2024) entered as anchor on the ptsd biomarkers claim.
Predicting high anger intensity using ecological momentary assessment and wearable-derived physiological data in a trauma-affected sample. (European journal of psychotraumatology 2025) entered as supporting on the ptsd biomarkers claim.
Long-term impact of combat-related traumatic injury on heart rate variability: findings from the ADVANCE study. (BMJ military health 2026) entered as supporting on the ptsd biomarkers claim.
SEP 29 2026
Seizure detection based on heart rate variability using a wearable electrocardiography device. (Epilepsia 2020) entered as anchor on the seizure detection claim.
Seizure detection using heart rate variability: A prospective validation study. (Epilepsia 2021) entered as anchor on the seizure detection claim.
SEP 30 2026
Heart rate variability as a potential biomarker for alcohol use disorders: A systematic review and meta-analysis. (Drug and alcohol dependence 2020) entered as supporting on the alcohol claim.
Heart rate variability in mental disorders: an umbrella review of meta-analyses. (Translational psychiatry 2025) entered as null_result on the anxiety claim.
Heart rate variability in mental disorders: an umbrella review of meta-analyses. (Translational psychiatry 2025) entered as null_result on the depression claim.
Ethnic differences in resting heart rate variability: a systematic review and meta-analysis. (Psychosomatic medicine 2015) entered as conflicting on the normal range age claim.
Heart rate variability in mental disorders: an umbrella review of meta-analyses. (Translational psychiatry 2025) entered as supporting on the ptsd biomarkers claim.
SEP 30 2026
Heart rate variability in mental disorders: an umbrella review of meta-analyses. (Translational psychiatry 2025) entered as a null result study on the anxiety claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 30 2026
Heart rate variability in mental disorders: an umbrella review of meta-analyses. (Translational psychiatry 2025) entered as a null result study on the depression claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 30 2026
Ethnic differences in resting heart rate variability: a systematic review and meta-analysis. (Psychosomatic medicine 2015) entered as a conflicting study on the normal range age claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
SEP 30 2026
Effect of exercise training on heart rate variability in type 2 diabetes mellitus patients: A systematic review and meta-analysis. (PloS one 2021) entered as anchor on the exercise training claim.
A systematic review and meta-analysis of heart rate variability in epilepsy and antiepileptic drugs. (Epilepsia 2012) entered as supporting on the seizure detection claim.
SEP 30 2026
Heart rate variability as a measure of mental stress in surgery: a systematic review. (International archives of occupational and environmental health 2021) entered as supporting on the occupational stress claim.
Work-related mental stress in confined tunnel construction environments: a field study with heart rate variability (HRV). (Ergonomics 2026) entered as supporting on the occupational stress claim.
Teachers' ambulatory heart rate variability as an outcome and moderating variable in the job demands-resources model. (Anxiety, stress, and coping 2021) entered as null_result on the occupational stress claim.
Heart rate variability as a dynamic marker of surgeons' stress during vascular surgery. (BJS open 2024) entered as supporting on the occupational stress claim.
Continuous heart rate variability monitoring, stress and recovery in doctors: a systematic review and meta-analysis. (Occupational medicine (Oxford, England) 2026) entered as anchor on the occupational stress claim.
Heart rate variability and occupational stress-systematic review. (Industrial health 2019) entered as anchor on the occupational stress claim.
SEP 30 2026
Teachers' ambulatory heart rate variability as an outcome and moderating variable in the job demands-resources model. (Anxiety, stress, and coping 2021) entered as a null result study on the occupational stress claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 30 2026
Heart rate variability in bipolar disorder: A systematic review and meta-analysis. (Neuroscience and biobehavioral reviews 2017) entered as anchor on the bipolar claim.
Heart rate variability in bipolar disorder and borderline personality disorder: a clinical review. (Evidence-based mental health 2018) entered as supporting on the bipolar claim.
SEP 30 2026
Cold Water Immersion, Heart Rate Variability and Post-Exercise Recovery: A Systematic Review. (Physiotherapy research international : the journal for researchers and clinicians in physical therapy 2025) entered as anchor on the cold water immersion claim.
SEP 30 2026
Heart Rate Variability in the Diagnostics and CPAP Treatment of Obstructive Sleep Apnea. (Advances in experimental medicine and biology 2019) entered as supporting on the hrv apnea detection claim.
Electrocardiogram heart rate variability for machine learning diagnosis of obstructive sleep Apnoea: A bayesian meta-analysis. (Sleep & breathing = Schlaf & Atmung 2025) entered as anchor on the hrv apnea detection claim.
Ultra-short term Heart Rate Variability in moderate and severe Obstructive Sleep Apnea. (Respiratory medicine 2026) entered as supporting on the hrv apnea detection claim.
Heart and Respiration Rate Variability Analysis to Estimate the Apnoea-Hypopnoea Index in People With Intellectual Disabilities. (Journal of intellectual disability research : JIDR 2026) entered as supporting on the hrv apnea detection claim.
Heart rate variability and obstructive sleep apnea: Current perspectives and novel technologies. (Journal of sleep research 2021) entered as supporting on the hrv apnea detection claim.
Detecting sleep apnea using non-linear measures of heart rate variability. (Respiratory research 2026) entered as supporting on the hrv apnea detection claim.
SEP 30 2026
A well-powered test of task difficulty effects on cardiovascular indicators of mental effort. (International journal of psychophysiology : official journal of the International Organization of Psychophysiology 2026) entered as null_result on the cognitive workload claim.
Cardiac Measures of Cognitive Workload: A Meta-Analysis. (Human factors 2020) entered as anchor on the cognitive workload claim.
Workload Intensity in Human-Robot Collaboration: A Personalized Approach to Sustainable Efficiency and Well-Being. (Human factors 2026) entered as supporting on the cognitive workload claim.
Heart Rate Variability and Body Motion as Digital Biomarkers of Task Workload During Military En Route Critical Care Simulations. (Sensors (Basel, Switzerland) 2026) entered as supporting on the cognitive workload claim.
SEP 30 2026
A well-powered test of task difficulty effects on cardiovascular indicators of mental effort. (International journal of psychophysiology : official journal of the International Organization of Psychophysiology 2026) entered as a null result study on the cognitive workload claim, bearing on the core claim.
It caps the rating until reconciled.
SEP 30 2026
Heart rate variability and self-control--A meta-analysis. (Biological psychology 2016) entered as anchor on the self control claim.
OCT 2 2026
GLP-1 receptor stimulation depresses heart rate variability and inhibits neurotransmission to cardiac vagal neurons. (Cardiovascular research 2011) entered as supporting on the glp1_heart_rate_hrv claim.
Exenatide acutely increases heart rate in parallel with augmented sympathetic nervous system activation in healthy overweight males. (British journal of clinical pharmacology 2016) entered as supporting on the glp1_heart_rate_hrv claim.
Heart and health behavior responses to GLP-1 receptor agonists: a 12-wk study using wearable technology and causal inference. (American journal of physiology. Heart and circulatory physiology 2025) entered as supporting on the glp1_heart_rate_hrv claim.
Heart rate acceleration with GLP-1 receptor agonists in type 2 diabetes patients: an acute and 12-week randomised, double-blind, placebo-controlled trial. (European journal of endocrinology 2017) entered as anchor on the glp1_heart_rate_hrv claim.
Effects of Liraglutide on Heart Rate and Heart Rate Variability: A Randomized, Double-Blind, Placebo-Controlled Crossover Study. (Diabetes care 2017) entered as anchor on the glp1_heart_rate_hrv claim.
OCT 2 2026
Limited Validity of the Low-Cost Coospo H808S Heart-Rate Monitor Compared to the Polar H10. (International journal of sports physiology and performance 2025) entered as anchor on the measurement validity claim.
OCT 2 2026
Efficacy and Methodology of Remote Heart Rate Variability Biofeedback Interventions for Mental Health: A Systematic Review and Meta-Analysis. (Applied psychophysiology and biofeedback 2026) entered as supporting on the biofeedback anxiety claim.
Heart Rate Variability and Prognosis in Hemodialysis Patients: A Meta-Analysis. (Blood purification 2021) entered as supporting on the prognostic in cardiac disease claim.
Resting respiratory sinus arrhythmia and posttraumatic stress disorder: A meta-analysis. (Biological psychology 2019) entered as supporting on the ptsd biomarkers claim.
OCT 3 2026
Reference values for time- and frequency-domain heart rate variability measures. (Heart rhythm 2018) entered as anchor on the normal range age claim.
Heart rate variability: reference values and role for clinical profile and mortality in individuals with heart failure. (Clinical research in cardiology : official journal of the German Cardiac Society 2024) entered as anchor on the prognostic in cardiac disease claim.
OCT 7 2026
The effects of non-pharmacological interventions on vagally-mediated heart rate variability (vmHRV) in individuals with depression: A systematic review and meta-analysis. (Neuroscience and biobehavioral reviews 2025) entered as supporting on the depression claim.
Heart Rate Variability in Anorexia Nervosa: A Systematic Review and Meta-Analysis on the Moderating Role of Measurement Duration and Clinical Stage. (European eating disorders review : the journal of the Eating Disorders Association 2026) entered as supporting on the measurement duration claim.
Accuracy of Photoplethysmography-Derived Pulse Rate Variability Compared with Electrocardiography-Derived Heart Rate Variability: A Systematic Review and Meta-Analysis. (Sensors (Basel, Switzerland) 2026) entered as supporting on the measurement validity claim.
OCT 15 2026
Validity of a Smartphone Application and Chest Strap for Recording RR Intervals at Rest in Athletes. (International journal of sports physiology and performance 2020) entered as supporting on the chest strap accuracy claim.
Change in heart rate variability with increasing time-on-task as a marker for mental fatigue: A systematic review. (Biological psychology 2024) entered as supporting on the cognitive workload claim.
Heart rate dynamics for cognitive load estimation in a driving simulation task. (Scientific reports 2024) entered as anchor on the cognitive workload claim.
A meta-analysis of heart rate variability in major depression. (Psychological medicine 2020) entered as anchor on the depression claim.
Monitoring Athletic Training Status Through Autonomic Heart Rate Regulation: A Systematic Review and Meta-Analysis. (Sports medicine (Auckland, N.Z.) 2017) entered as supporting on the exercise training claim.
Validation of a Textile-Based Wearable Measuring Electrocardiogram and Breathing Frequency for Sleep Apnea Monitoring. (Sensors (Basel, Switzerland) 2024) entered as supporting on the hrv apnea detection claim.
Reliability and inter-device agreement of multi-site heart rate variability measurements during transcutaneous auricular vagus nerve stimulation: a prospective single-arm methodological physiological study. (BMC cardiovascular disorders 2026) entered as conflicting on the measurement validity claim.
Changes and prognostic significance of autonomic cardiac regulation during ageing. (Autonomic neuroscience : basic & clinical 2025) entered as anchor on the normal range age claim.
Normative Values of Short-Term Heart Rate Variability Parameters in Koreans and Their Clinical Value for the Prediction of Mortality. (Heart, lung & circulation 2018) entered as supporting on the normal range age claim.
Reference values for short-term resting-state heart rate variability in healthy adults: Results from the Brazilian Longitudinal Study of Adult Health-ELSA-Brasil study. (Psychophysiology 2019) entered as anchor on the normal range age claim.
Age-related losses in cardiac autonomic activity during a daytime nap. (Psychophysiology 2022) entered as conflicting on the normal range age claim.
Changes and prognostic significance of autonomic cardiac regulation during ageing. (Autonomic neuroscience : basic & clinical 2025) entered as supporting on the physiological claim.
OCT 15 2026
Reliability and inter-device agreement of multi-site heart rate variability measurements during transcutaneous auricular vagus nerve stimulation: a prospective single-arm methodological physiological study. (BMC cardiovascular disorders 2026) entered as a conflicting study on the measurement validity claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
OCT 15 2026
Age-related losses in cardiac autonomic activity during a daytime nap. (Psychophysiology 2022) entered as a conflicting study on the normal range age claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
OCT 17 2026
Feasibility and Effectiveness of Portable/Remote Heart Rate Variability (HRV) Biofeedback Training in Treating Stress and Mental Health Difficulties: A Systematic Review. (Applied psychophysiology and biofeedback 2026) entered as supporting on the biofeedback anxiety claim.
Effects of aerobic training intensity on resting, exercise and post-exercise blood pressure, heart rate and heart-rate variability. (Journal of human hypertension 2010) entered as null_result on the exercise training claim.
Physical activity and heart rate variability in older adults: the Cardiovascular Health Study. (Circulation 2014) entered as supporting on the exercise training claim.
OCT 17 2026
Effects of aerobic training intensity on resting, exercise and post-exercise blood pressure, heart rate and heart-rate variability. (Journal of human hypertension 2010) entered as a null result study on the exercise training claim, flagged as bearing on a secondary point, not the core direction.
Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.
OCT 24 2026
Feasible assessment of recovery and cardiovascular health: accuracy of nocturnal HR and HRV assessed via ring PPG in comparison to medical grade ECG. (Physiological measurement 2020) entered as anchor on the oura_hrv_validity claim.
Validation of nocturnal resting heart rate and heart rate variability in consumer wearables. (Physiological reports 2025) entered as anchor on the oura_hrv_validity claim.
Accuracy Assessment of Oura Ring Nocturnal Heart Rate and Heart Rate Variability in Comparison With Electrocardiography in Time and Frequency Domains: Comprehensive Analysis (Journal of Medical Internet Research 2022) entered as anchor on the oura_hrv_validity claim.
Assessing the Accuracy of Popular Commercial Technologies That Measure Resting Heart Rate and Heart Rate Variability (Frontiers in Sports and Active Living 2021) entered as supporting on the oura_hrv_validity claim.
Deriving Accurate Nocturnal Heart Rate, rMSSD and Frequency HRV from the Oura Ring. (Sensors (Basel, Switzerland) 2024) entered as anchor on the oura_hrv_validity claim.
OCT 24 2026
Estimation of Heart Rate Variability Measures Using Apple Watch and Evaluating Their Accuracy (PErvasive Technologies Related to Assistive Environments Conference (PETRA) 2021) entered as supporting on the apple_watch_hrv_validity claim.
Validation of the Apple Watch for Heart Rate Variability Measurements during Relax and Mental Stress in Healthy Subjects. (Sensors (Basel, Switzerland) 2018) entered as supporting on the apple_watch_hrv_validity claim.
The Validity of Apple Watch Series 9 and Ultra 2 for Serial Measurements of Heart Rate Variability and Resting Heart Rate. (Sensors (Basel, Switzerland) 2024) entered as anchor on the apple_watch_hrv_validity claim.
Validity of Heart Rate Variability Measured with Apple Watch Series 6 Compared to Laboratory Measures. (Sensors (Basel, Switzerland) 2025) entered as anchor on the apple_watch_hrv_validity claim.
02 Revision Log
OCT 24 2026
apple_watch_hrv_validity: opened at Uncertain
Opened at Uncertain by rule from the current evidence for: Apple Watch measures heart rate variability in close agreement with an ECG or chest-strap reference..
OCT 24 2026
oura_hrv_validity: opened at Established
Opened at Established by rule from the current evidence for: The Oura Ring measures overnight heart rate variability in close agreement with an ECG reference..
OCT 15 2026
cognitive workload: Uncertain → Emerging
Moved to Emerging by rule from the current evidence for: Heart rate variability changes measurably in response to cognitive workload..
OCT 3 2026
prognostic in cardiac disease: Emerging → Established
Moved to Established by rule from the current evidence for: Low heart rate variability predicts mortality in people with heart failure..
OCT 2 2026
glp1_heart_rate_hrv: opened at Established
Opened at Established by rule from the current evidence for: GLP-1 receptor agonists raise resting heart rate and lower heart rate variability..
SEP 30 2026
self control: opened at Uncertain
Opened at Uncertain by rule from the current evidence for: Higher resting heart rate variability is associated with better self-control..
SEP 30 2026
cognitive workload: opened at Uncertain
Opened at Uncertain by rule from the current evidence for: Heart rate variability changes measurably in response to cognitive workload..
SEP 30 2026
hrv apnea detection: opened at Emerging
Opened at Emerging by rule from the current evidence for: Heart rate variability analysis detects obstructive sleep apnea accurately enough to screen for it..
SEP 30 2026
cold water immersion: opened at Emerging
Opened at Emerging by rule from the current evidence for: Cold water immersion after exercise accelerates parasympathetic reactivation as measured by heart rate variability..
SEP 30 2026
bipolar: opened at Emerging
Opened at Emerging by rule from the current evidence for: People with bipolar disorder have lower resting heart rate variability..
SEP 30 2026
occupational stress: opened at Emerging
Opened at Emerging by rule from the current evidence for: Higher occupational stress is associated with lower heart rate variability..
SEP 30 2026
anxiety: Established → Emerging
Moved to Emerging by rule from the current evidence for: People with an anxiety disorder have lower resting heart rate variability..
SEP 30 2026
depression: Established → Emerging
Moved to Emerging by rule from the current evidence for: People with major depression have lower resting heart rate variability..
SEP 29 2026
seizure detection: opened at Established
Opened at Established by rule from the current evidence for: An HRV algorithm on a wearable ECG detects seizures in patients with marked ictal autonomic change..
SEP 29 2026
ptsd biomarkers: opened at Emerging
Opened at Emerging by rule from the current evidence for: Wrist-wearable heart rate variability identifies posttraumatic neuropsychiatric symptoms after trauma exposure..
SEP 29 2026
prognostic in cardiac disease: opened at Emerging
Opened at Emerging by rule from the current evidence for: Low heart rate variability predicts mortality in people with heart failure..
SEP 29 2026
measurement duration: opened at Emerging
Opened at Emerging by rule from the current evidence for: A heart rate variability recording shorter than five minutes gives a reliable RMSSD..
SEP 29 2026
chest strap accuracy: opened at Established
Opened at Established by rule from the current evidence for: A chest-strap heart rate monitor agrees with ECG for HRV at rest..
SEP 29 2026
beta blockers: opened at Unsupported
Opened at Unsupported by rule from the current evidence for: Beta blockers lower heart rate variability..
SEP 29 2026
menstrual cycle: opened at Uncertain
Opened at Uncertain by rule from the current evidence for: Heart rate variability follows a consistent pattern across the menstrual cycle..
SEP 29 2026
air quality: opened at Emerging
Opened at Emerging by rule from the current evidence for: Higher indoor fine-particulate exposure lowers heart rate variability..
SEP 29 2026
cannabis: opened at Emerging
Opened at Emerging by rule from the current evidence for: Acute THC lowers heart rate variability..
SEP 29 2026
reactive aggression: opened at Unsupported
Opened at Unsupported by rule from the current evidence for: Lower heart rate variability predicts reactive aggression..
SEP 29 2026
antidepressants: opened at Uncertain
Opened at Uncertain by rule from the current evidence for: Antidepressant treatment lowers heart rate variability..
SEP 29 2026
anxiety: opened at Established
Opened at Established by rule from the current evidence for: People with an anxiety disorder have lower resting heart rate variability..
SEP 29 2026
depression: opened at Established
Opened at Established by rule from the current evidence for: People with major depression have lower resting heart rate variability..
SEP 29 2026
biofeedback cravings: opened at Emerging
Opened at Emerging by rule from the current evidence for: Heart rate variability biofeedback reduces craving in substance use disorder..
SEP 29 2026
slow breathing: opened at Uncertain
Opened at Uncertain by rule from the current evidence for: Slow-paced breathing raises heart rate variability more than breathing at a normal rate..
SEP 29 2026
biofeedback anxiety: opened at Uncertain
Opened at Uncertain by rule from the current evidence for: Heart rate variability biofeedback reduces anxiety..
SEP 29 2026
trait neuroticism: Emerging → Uncertain
Moved to Uncertain by rule from the current evidence for: Higher trait neuroticism is associated with lower resting heart rate variability..
SEP 29 2026
exercise training: opened at Established
Opened at Established by rule from the current evidence for: Regular exercise training increases heart rate variability..
SEP 29 2026
alcohol: opened at Established
Opened at Established by rule from the current evidence for: Acute alcohol consumption lowers heart rate variability..
SEP 29 2026
acute drop infection: opened at Emerging
Opened at Emerging by rule from the current evidence for: A fall in overnight heart rate variability precedes the onset of an acute infection..
SEP 29 2026
normal range age: opened at Established
Opened at Established by rule from the current evidence for: Resting heart rate variability declines with age in healthy people..
JUL 11 2026
trait neuroticism: opened at Emerging
Opened at Emerging by rule from the current evidence for: Higher trait neuroticism is associated with lower resting heart rate variability..
JUL 9 2026
measurement validity: opened at Uncertain
Opened at Uncertain by rule from the current evidence for: Consumer wearable devices measure HRV with sufficient agreement to a validated reference to be meaningful..
JUL 9 2026
physiological: opened at Established
Opened at Established by rule from the current evidence for: Lower heart rate variability is associated with worse cardiovascular and autonomic health outcomes..
This page interprets published research. It is not medical advice. The KnowYourPrime Research Desk rates the evidence supporting a claim, not the claim itself. It does not diagnose or treat. Talk to your own doctor about your health.