Activity · desk opened JUL 20 2026 · revision 4 Reviewed OCT 15 2026

Activity: What Holds Up and What Doesn't

Wrist trackers count steps well for ordinary walking and badly with a cane or walker. What step counts predict, and where the calorie numbers fall apart.

7 questions rated against 98 screened studies. Each rating is the evidence on that one question, not an average of the desk.

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Where the evidence stands · 7 questions rated the number beside each is how many studies sit behind it

Established 1 question

Do wearables measure heart rate accurately?61

Emerging 1 question

does device-measured physical activity predict better health outcomes13

Uncertain 4 questions

do activity trackers make people more active8
are consumer wearables accurate enough to trust for calorie/energy-expenditure estimates21
does 220 minus age (or similar age-based formulas) accurately predict max heart rate2
Can a fitness tracker detect depression?3

Unsupported 1 question

Does a wrist tracker still count steps right with a cane or walker?6

does device-measured physical activity predict better health outcomes

Rated proposition Higher wearable-measured physical activity is associated with lower all-cause mortality risk.

KnowYourPrime evidence rating Emerging Evidence currently favors the claim, but more confirmation is needed.

What the studies found Higher device-recorded physical activity reflects a genuine reduction in health risk, particularly mortality risk.

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.
Some evidence conflicts on secondary points that do not change the core direction.

Used in 1 article

Tracker Data Sorted Depression Scores About 80% Right1 shared study

13 studies scored · 2 anchor · 7 supporting · 3 commentary (not counted) · Evidence last evaluated Oct 15, 2026

do activity trackers make people more active

Rated proposition Wearable activity tracker use increases physical activity participation.

KnowYourPrime evidence rating Uncertain Evidence is conflicting, inconsistent, or difficult to interpret.

KnowYourPrime Evidence RegistryFinding KYP-ER-0012, the permanent, citable record of this rating

What the studies found Using a consumer wearable activity tracker increases how physically active people actually become.

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.
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 Wearing a Fitness Tracker Actually Make You More Active?1 shared study
How Accurate Is the Calorie Count on Your Watch?1 shared study

8 studies scored · 1 anchor · 4 supporting · 1 conflicting · 1 null-result · 1 commentary (not counted) · Evidence last evaluated Oct 15, 2026

Do wearables measure heart rate accurately?

Rated proposition Consumer wearable devices measure heart rate with accuracy comparable to reference standards.

KnowYourPrime evidence rating Established Strong, consistent evidence supports the claim.

KnowYourPrime Evidence RegistryFinding KYP-ER-0009, the permanent, citable record of this rating

What the studies found Wrist wearables measure heart rate accurately against a chest-strap or ECG reference at rest, with agreement falling away as movement increases.

Systematic-review or meta-analytic 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 5 articles

How Does Your Watch Actually Count Steps?8 shared studies
Step Counts Hold Up in Parkinson's, Less Known for Stroke3 shared studies
How Accurate Is the Calorie Count on Your Watch?7 shared studies
Tracker Data Sorted Depression Scores About 80% Right1 shared study
Your Smartwatch May Undercount Steps If You Use a Cane or Walker1 shared study

61 studies scored · 5 anchor · 53 supporting · 1 conflicting · 1 commentary (not counted) · Evidence last evaluated Oct 15, 2026

are consumer wearables accurate enough to trust for calorie/energy-expenditure estimates

Rated proposition Consumer wearable devices measure energy expenditure with accuracy comparable to reference standards.

KnowYourPrime evidence rating Uncertain Evidence is conflicting, inconsistent, or difficult to interpret.

KnowYourPrime Evidence RegistryFinding KYP-ER-0010, the permanent, citable record of this rating

What the studies found Consumer wearables measure calorie/energy-expenditure accurately enough to be meaningful.

Multiple supporting studies are consistent with the core relationship.
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 runs contrary to this claim, so the evidence is treated as unsettled rather than affirming.
An anchor study was assessed but it does not test this claim’s core relationship directly, so the evidence is treated as unsettled rather than affirming.
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.
At least one unresolved conflicting study bears on the core claim, capping the rating until reconciled.
Some evidence conflicts on secondary points that do not change the core direction.

Used in 3 articles

How Accurate Is the Calorie Count on Your Watch?4 shared studies
How Does Your Watch Actually Count Steps?2 shared studies
Tracker Data Sorted Depression Scores About 80% Right1 shared study

21 studies scored · 4 anchor · 14 supporting · 2 conflicting · 1 commentary (not counted) · Evidence last evaluated Oct 15, 2026

does 220 minus age (or similar age-based formulas) accurately predict max heart rate

Rated proposition Age-predicted maximal-heart-rate equations match an individual’s actual measured maximal heart rate.

KnowYourPrime evidence rating Uncertain Evidence is conflicting, inconsistent, or difficult to interpret.

What the studies found Age-based formulas such as 220-minus-age accurately predict an individual's true maximal heart rate.

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 runs contrary to this claim, so the evidence is treated as unsettled rather than affirming.

Used in 1 article

Is 220 Minus Your Age Actually Your Max Heart Rate?2 shared studies

2 studies scored · 2 anchor · Evidence last evaluated Oct 15, 2026

Does a wrist tracker still count steps right with a cane or walker?

Rated proposition A wrist-worn wearable counts steps accurately when a mobility aid is used.

KnowYourPrime evidence rating Unsupported Existing evidence does not support the claim.

What the studies found A wrist tracker undercounts badly when you use a walker or walk slowly. An Apple Watch lost 36% of steps with a rolling walker, and a wrist Fitbit ran 31% error where the same Fitbit on a hip ran 1.5%.

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

Your Smartwatch May Undercount Steps If You Use a Cane or Walker2 shared studies
Step Counts Hold Up in Parkinson's, Less Known for Stroke2 shared studies

6 studies scored · 1 supporting · 3 conflicting · 2 null-result · Evidence last evaluated Oct 15, 2026

Can a fitness tracker detect depression?

Rated proposition Wearable-derived data detects depressive symptoms.

KnowYourPrime evidence rating Uncertain Evidence is conflicting, inconsistent, or difficult to interpret.

What the studies found Wearable data sorted depression severity at an AUC of 0.82 across a student and an outpatient sample. Reviews of the wider literature put the predictive ability lower and call it unready for clinical use.

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.
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 1 article

Tracker Data Sorted Depression Scores About 80% Right3 shared studies

3 studies scored · 2 anchor · 1 supporting · Evidence last evaluated Oct 15, 2026

MAINTAINED BY The KnowYourPrime Research Desk · reviewed against new evidence on a rolling basis

Evidence on: Higher wearable-measured physical activity is associated with lower all-cause mortality risk.

13 scored

Anchor Studies2

Wearable-device-measured physical activity and future health risk.

Journal

Nature medicine · 2020

PMID

32807930

RCR

14.5

Citations

253

Study type

Primary study

accelerometryenergy metabolism

Daily Step Counts for Measuring Physical Activity Exposure and Its Relation to Health.

Journal

Medicine and science in sports and exercise · 2019

PMID

31095077

RCR

11.9

Citations

231

Study type

Systematic review

accelerometrybiomedical research

Supporting Studies7

Association of Perioperative Steps and Heart Rate Variability from Wearable Devices with Surgical Outcomes.

Journal

Journal of the American College of Surgeons · 2026

PMID

42089531

Citations

Study type

Primary study

Sample size

66,345 patients

humansfemale

Predicting incident type 2 diabetes using wearable activity and polygenic risk: A survival-modeling study in All of Us.

Journal

The Journal of clinical endocrinology and metabolism · 2026

PMID

41396877

Citations

Study type

Primary study

Sample size

4589 adults

humansdiabetes mellitus, type 2

Digital Biomarkers for Depression Screening With Wearable Devices: Cross-sectional Study With Machine Learning Modeling.

Journal

JMIR mHealth and uHealth · 2021

PMID

34694233

RCR

8.7

Citations

102

Study type

Primary study

Sample size

n = 170

adultbiomarkers

Preoperative Decline and Postoperative Recovery of Wearable-Derived Physical Activity over a Four-Year Perioperative Period in Total Knee and Hip Arthroplasty.

Journal

Sensors (Basel, Switzerland) · 2026

PMID

42280838

Citations

Study type

Primary study

Sample size

238 participants

humansarthroplasty, replacement, hip

Impact of Extravalvular Remodeling on Wearable Smartwatch-Recorded Physical Activity in Patients Undergoing Transcatheter Aortic Valve Implantation for Severe Symptomatic Aortic Stenosis.

Journal

Journal of the American Heart Association · 2026

PMID

41944153

Citations

Study type

Primary study

humansaortic valve stenosis

Association Between Wearable Device Measured Activity and Patient-Reported Outcomes for Heart Failure.

Journal

JACC. Heart failure · 2023

PMID

37498273

RCR

3.0

Citations

Study type

Randomized controlled trial

Sample size

425 patients

humansfemale

Device-Measured Sleep Characteristics, Daily Step Count, and Cardiometabolic Health Markers: Findings From the Prospective Physical Activity, Sitting, and Sleep (ProPASS) Consortium.

Journal

Circulation. Cardiovascular quality and outcomes · 2025

PMID

40703058

RCR

1.4

Citations

Study type

Primary study

Sample size

n = 11

humansfemale

Retired / Excluded1

Validity of energy expenditure estimation methods during 10 days of military training.

Journal

Scandinavian journal of medicine & science in sports · 2019

PMID

31136027

RCR

2.7

Citations

Study type

Validity study

accelerometryadult

Letters, Editorials and Comments (not counted in the rating)3

Beyond the snapshot: harnessing daily physical activity for heart failure characterization.

Journal

Clinical research in cardiology : official journal of the German Cardiac Society · 2025

PMID

39167192

Bears on

Secondary point

Device-measured physical activity and type 2 diabetes mellitus risk.

Journal

Frontiers in endocrinology · 2024

PMID

38179306

Study type

Primary study

Sample size

90,044 participants

Bears on

Secondary point

humansprospective studies

Quantifying population levels of physical activity in Africa using wearable sensors: implications for global physical activity surveillance.

Journal

BMJ open sport & exercise medicine · 2026

PMID

33868705

Study type

Primary study

Bears on

Secondary point

Evidence on: Wearable activity tracker use increases physical activity participation.

8 scored

Anchor Studies1

Consumer-Based Wearable Activity Trackers Increase Physical Activity Participation: Systematic Review and Meta-Analysis.

Journal

JMIR mHealth and uHealth · 2020

PMID

30977740

RCR

23.0

Citations

405

Study type

Meta-analysis

exercisefitness trackers

Supporting Studies4

A Web-Based Pedometer-Mediated Intervention Maintains Benefits After Pulmonary Rehabilitation: A Pilot Study.

Journal

International journal of chronic obstructive pulmonary disease · 2026

PMID

42610055

Citations

Study type

Primary study

Sample size

n = 20

humanspilot projects

The use of artificial intelligence and wearable devices in enhanced recovery after surgery pathways following radical cystectomy: A systematic review.

Journal

The Journal of international medical research · 2026

PMID

42750161

Citations

Study type

Systematic review

humanscystectomy

Use of commercially available wearable devices for physical rehabilitation in healthcare: a systematic review.

Journal

BMJ open · 2024

PMID

39515863

RCR

4.1

Citations

Study type

Systematic review

Sample size

1754 patients

humanswearable electronic devices

A Web-Based, Pedometer-Mediated Intervention Increases Amount and Intensity of Physical Activity in COPD: A Randomized Controlled Trial.

Journal

International journal of chronic obstructive pulmonary disease · 2026

PMID

42701779

Citations

Study type

Randomized controlled trial

humanspulmonary disease, chronic obstructive

Conflicting Studies1

Activity monitors for increasing physical activity in adult stroke survivors.

Journal

The Cochrane database of systematic reviews · 2018

PMID

30051462

RCR

5.2

Citations

Study type

Meta-analysis

Sample size

245 participants

Bears on

Secondary point

adultaged

Null-Result Studies1

Effectiveness of Minimal Contact Interventions: An RCT.

Journal

American journal of preventive medicine · 2021

PMID

33612170

RCR

0.5

Citations

Study type

Randomized controlled trial

Bears on

Core claim

adolescentadult

Letters, Editorials and Comments (not counted in the rating)1

Editorial: Wearable Sensors for Remote Health Monitoring and Intelligent Disease Management.

Journal

Frontiers in sports and active living · 2021

PMID

34927069

Bears on

Secondary point

Evidence on: Consumer wearable devices measure heart rate with accuracy comparable to reference standards.

61 scored

Anchor Studies5

Reliability and Validity of Commercially Available Wearable Devices for Measuring Steps, Energy Expenditure, and Heart Rate: Systematic Review.

Journal

JMIR mHealth and uHealth · 2021

PMID

32897239

RCR

37.3

Citations

464

Study type

Systematic review

Sample size

n = 158

energy metabolismfitness trackers

Accuracy and Acceptability of Wrist-Wearable Activity-Tracking Devices: Systematic Review of the Literature.

Journal

Journal of medical Internet research · 2022

PMID

35060915

RCR

17.8

Citations

145

Study type

Systematic review

exercisefitness trackers

Keeping Pace with Wearables: A Living Umbrella Review of Systematic Reviews Evaluating the Accuracy of Consumer Wearable Technologies in Health Measurement.

Journal

Sports medicine (Auckland, N.Z.) · 2024

PMID

39080098

RCR

15.1

Citations

Study type

Systematic review

Sample size

n = 249

humansexercise

Accuracy and Precision of Energy Expenditure, Heart Rate, and Steps Measured by Combined-Sensing Fitbits Against Reference Measures: Systematic Review and Meta-analysis.

Journal

JMIR mHealth and uHealth · 2022

PMID

35416777

RCR

7.7

Citations

Study type

Meta-analysis

Sample size

n = 117

accelerometryenergy metabolism

Validity of Wrist-Worn photoplethysmography devices to measure heart rate: A systematic review and meta-analysis.

Journal

Journal of sports sciences · 2020

PMID

32552580

RCR

4.4

Citations

Study type

Meta-analysis

accelerometryactivities of daily living

Supporting Studies53

The validity and reliability of consumer-grade activity trackers in older, community-dwelling adults: A systematic review.

Journal

Maturitas · 2018

PMID

29704922

RCR

7.8

Citations

113

Study type

Systematic review

Sample size

290 adults

actigraphyaged

Wearable activity trackers-advanced technology or advanced marketing?

Journal

European journal of applied physiology · 2022

PMID

35445837

RCR

9.8

Citations

Study type

Review

fitness trackershumans

Recommendations for determining the validity of consumer wearable and smartphone step count: expert statement and checklist of the INTERLIVE network.

Journal

British journal of sports medicine · 2021

PMID

33361276

RCR

6.8

Citations

Study type

Systematic review

adolescentadult

Wrist-worn devices for the measurement of heart rate and energy expenditure: A validation study for the Apple Watch 6, Polar Vantage V and Fitbit Sense.

Journal

European journal of sport science · 2023

PMID

34957939

RCR

7.6

Citations

Study type

Primary study

Sample size

30 men

malehumans

Standardizing Analytic Methods and Reporting in Activity Monitor Validation Studies.

Journal

Medicine and science in sports and exercise · 2020

PMID

30913159

RCR

5.6

Citations

Study type

Review

Sample size

n = 23

accelerometrycalibration

Quality Evaluation of Free-living Validation Studies for the Assessment of 24-Hour Physical Behavior in Adults via Wearables: Systematic Review.

Journal

JMIR mHealth and uHealth · 2022

PMID

35679106

RCR

3.9

Citations

Study type

Systematic review

adultexercise

Recommendations for Determining the Validity of Consumer Wearables and Smartphones for the Estimation of Energy Expenditure: Expert Statement and Checklist of the INTERLIVE Network.

Journal

Sports medicine (Auckland, N.Z.) · 2022

PMID

35260991

RCR

3.5

Citations

Study type

Systematic review

checklistenergy metabolism

Assessment of 24-hour physical behaviour in adults via wearables: a systematic review of validation studies under laboratory conditions.

Journal

The international journal of behavioral nutrition and physical activity · 2023

PMID

37291598

RCR

2.7

Citations

Study type

Systematic review

Sample size

n = 420

humansadult

Sensing leg movement enhances wearable monitoring of energy expenditure.

Journal

Nature communications · 2021

PMID

34257310

RCR

3.8

Citations

Study type

Primary study

energy metabolismexercise

A catalog of validity indices for step counting wearable technologies during treadmill walking: the CADENCE-adults study.

Journal

The international journal of behavioral nutrition and physical activity · 2022

PMID

36076265

RCR

3.5

Citations

Study type

Primary study

adultchild

Using Free-Living Heart Rate Data as an Objective Method to Assess Physical Activity: A Scoping Review and Recommendations by the INTERLIVE-Network Targeting Consumer Wearables.

Journal

Sports medicine (Auckland, N.Z.) · 2025

PMID

39893599

RCR

3.7

Citations

Study type

Review

Sample size

n = 72

humansheart rate

Validity of Apple Watch 6 and Polar A370 for monitoring energy expenditure while resting or performing light to vigorous physical activity.

Journal

Journal of science and medicine in sport · 2023

PMID

37517888

RCR

2.0

Citations

Study type

Randomized controlled trial

Sample size

n = 11

young adulthumans

A meta-analysis of Fitbit devices: same company, different models, different validity evidence.

Journal

Journal of medical engineering & technology · 2022

PMID

34881682

RCR

1.8

Citations

Study type

Meta-analysis

databases, factualenergy metabolism

Are Wrist-Worn Activity Trackers and Mobile Applications Valid for Assessing Physical Activity in High School Students? Wearfit Study.

Journal

Journal of sports science & medicine · 2022

PMID

36157395

RCR

2.9

Citations

Study type

Primary study

accelerometryadolescent

Validity of energy expenditure estimation methods during 10 days of military training.

Journal

Scandinavian journal of medicine & science in sports · 2019

PMID

31136027

RCR

2.7

Citations

Study type

Validity study

accelerometryadult

Step-count outcomes of 13 different activity trackers: Results from laboratory and free-living experiments.

Journal

Gait & posture · 2022

PMID

36030707

RCR

2.6

Citations

Study type

Primary study

adulthumans

Validity of Wrist-Worn Activity Trackers for Estimating VO 2max and Energy Expenditure.

Journal

International journal of environmental research and public health · 2020

PMID

31443347

RCR

1.9

Citations

Study type

Primary study

adultenergy metabolism

Accuracy of the Multisensory Wristwatch Polar Vantage's Estimation of Energy Expenditure in Various Activities: Instrument Validation Study.

Journal

JMIR mHealth and uHealth · 2020

PMID

31579020

RCR

1.5

Citations

Study type

Primary study

Sample size

30 volunteers

accelerometryadult

Criterion-Related Validity of Consumer-Wearable Activity Trackers for Estimating Steps in Primary Schoolchildren under Controlled Conditions: Fit-Person Study.

Journal

Journal of sports science & medicine · 2024

PMID

38455433

RCR

1.0

Citations

Study type

Primary study

femalehumans

Raw Photoplethysmography as an Enhancement for Research-Grade Wearable Activity Monitors.

Journal

JMIR mHealth and uHealth · 2024

PMID

39331461

RCR

2.0

Citations

Study type

Primary study

photoplethysmographyhumans

Fitness band accuracy in older community dwelling adults.

Journal

Health informatics journal · 2020

PMID

28743215

RCR

0.7

Citations

Study type

Primary study

Sample size

30 participants

accelerometryaged, 80 and over

Factors associated with validity of consumer-oriented wearable physical activity trackers: a meta-analysis.

Journal

Journal of medical engineering & technology · 2021

PMID

33750250

RCR

0.4

Citations

Study type

Meta-analysis

databases, factualenergy metabolism

Apple watch accuracy in monitoring health metrics: a systematic review and meta-analysis.

Journal

Physiological measurement · 2025

PMID

40199339

RCR

1.8

Citations

Study type

Meta-analysis

Sample size

n = 56

humansenergy metabolism

Validation of an Open-Source Smartwatch for Continuous Monitoring of Physical Activity and Heart Rate in Adults.

Journal

Sensors (Basel, Switzerland) · 2025

PMID

40363363

Citations

Study type

Validity study

Sample size

n = 47

humansheart rate

Comparison of consumer-grade wearable devices with a research-grade instrument for measuring physical activity in a free-living setting.

Journal

PloS one · 2026

PMID

41729926

Citations

Study type

Comparative study

Sample size

n = 21

humanswearable electronic devices

Validity of four low-cost smartwatches in estimating energy expenditure during cycling in Chinese untrained women.

Journal

PloS one · 2025

PMID

40986546

Citations

Study type

Primary study

adultfemale

Performance Evaluation of Device-Based Algorithms to Estimate Step Counts in Free-Living Adults Compared with Direct Observation.

Journal

Medicine and science in sports and exercise · 2026

PMID

42456002

Citations

Study type

Comparative study

humansalgorithms

Is my smartwatch a valid witness? A systematic review and meta-analysis.

Journal

Forensic science international · 2026

PMID

41819643

Citations

Study type

Meta-analysis

humanswearable electronic devices

Validation of a novel multi-sensor wearable for measuring heart rate, steps, and energy expenditure in laboratory and simulated free-living protocols.

Journal

Physiological measurement · 2026

PMID

42229511

Citations

Study type

Validity study

humansenergy metabolism

Benchmarking open-source step counting algorithms for wrist-worn devices.

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

41335822

Citations

Study type

Primary study

humansalgorithms

Aggregation Periods Influence Step Count Error in Low-Power Wearables.

Journal

Sensors (Basel, Switzerland) · 2025

PMID

41305204

Citations

Study type

Primary study

humanswearable electronic devices

Accurate measurement of simulated slow and altered walking activity: Apple Watch best in class wearable devices.

Journal

PloS one · 2025

PMID

41124109

Citations

Study type

Primary study

humanswearable electronic devices

Step Count Accuracy of the Life Plus Connected Watch at Different Localizations and Speeds in Healthy Adults, Patients With Cardiovascular Disease, and Patients With Peripheral Artery Disease: Step Count Validation Study in Laboratory Settings.

Journal

JMIR formative research · 2025

PMID

39930990

Citations

Study type

Validity study

Sample size

n = 10

humansperipheral arterial disease

Validation of steps countering recorded with a smartwatch

Journal

The Journal of Sports Medicine and Physical Fitness · 2024

DOI

10.23736/S0022-4707.24.15888-4

Validation of a wireless device-driven method of estimating caloric expenditure during running.

Journal

Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme · 2026

PMID

42330544

Citations

Study type

Validity study

humansenergy metabolism

Accuracy of energy expenditure estimation by the Apple Watch in EMS-supported exercise.

Journal

Physiological measurement · 2025

PMID

40825349

Citations

Study type

Primary study

humansenergy metabolism

Validity of a Consumer-Based Wearable to Measure Clinical Parameters in Patients With Chronic Obstructive Pulmonary Disease and Healthy Controls: Observational Study.

Journal

JMIR mHealth and uHealth · 2024

PMID

39504450

RCR

3.7

Citations

Study type

Observational study

Sample size

30 patients

humanspulmonary disease, chronic obstructive

Step count accuracy and reliability of two activity tracking devices in people after stroke.

Journal

Physiotherapy theory and practice · 2018

PMID

28777710

RCR

3.0

Citations

Study type

Comparative study

actigraphyadult

Accuracy of wearable physical activity trackers in people with Parkinson's disease.

Journal

Gait & posture · 2018

PMID

29729611

RCR

3.7

Citations

Study type

Primary study

accelerometryaged

The Effect of Assistive Devices on the Accuracy of Fitbits in Healthy Individuals: A Brief Report.

Journal

International journal of environmental research and public health · 2025

PMID

40724167

Citations

Study type

Primary study

Sample size

n = 11

humansmale

Wearable technology for mobility measurement in orthopedics and traumatology: a comparison of commercially available systems.

Journal

Archives of orthopaedic and trauma surgery · 2025

PMID

40088311

Citations

Study type

Comparative study

Sample size

40 participants

humanswearable electronic devices

Comparison of Students' Physical Activity at Different Times and Establishment of a Regression Model for Smart Fitness Trackers.

Journal

Sensors (Basel, Switzerland) · 2025

PMID

40292814

Citations

Study type

Comparative study

humansmale

Analysis of a Medically Certified, Wrist-Worn Sensor for the Assessment of Heart Rate and Energy Expenditure During Daily Activities in Patients With Chronic Heart Failure or Coronary Artery Disease and Recreational Athletes: Validation Study.

Journal

JMIR cardio · 2026

PMID

41027033

Citations

Study type

Validity study

Sample size

57 patients

heart rate determinationenergy metabolism

Consumer Smartwatch Technology in Health and Performance Research: Validity, Limitations, and Real-World Applications.

Journal

Sensors (Basel, Switzerland) · 2026

PMID

42515370

Citations

Study type

Review

humansdigital health

Step count accuracy of StepWatch and FitBit One™ among individuals with a unilateral transtibial amputation.

Journal

Prosthetics and orthotics international · 2019

PMID

29623810

RCR

1.5

Citations

Study type

Primary study

accelerometryadolescent

Validity and Reliability Evaluation of Four Commercial Activity Trackers' Step Counting Performance.

Journal

Telemedicine journal and e-health : the official journal of the American Telemedicine Association · 2019

PMID

29303680

RCR

0.9

Citations

Study type

Primary study

accelerometryadult

Validity of Wearable Activity Monitors during Cycling and Resistance Exercise.

Journal

Medicine and science in sports and exercise · 2018

PMID

29189666

RCR

8.0

Citations

132

Study type

Validity study

Sample size

28 women

adultbicycling

Assessment of step accuracy using the Consumer Technology Association standard.

Journal

Journal of sports sciences · 2019

PMID

29958058

RCR

1.3

Citations

Study type

Comparative study

adolescentadult

Validity of the "Samsung Health" application to measure steps: A study with two different samsung smartphones.

Journal

Journal of sports sciences · 2019

PMID

30332917

RCR

0.9

Citations

Study type

Validity study

abdomenactigraphy

A Step in the Right Direction: Body Location Determines Activity Tracking Device Accuracy in Total Knee and Hip Arthroplasty Patients.

Journal

The Journal of the American Academy of Orthopaedic Surgeons · 2020

PMID

31884504

RCR

1.3

Citations

Study type

Observational study

Sample size

n = 24

agedankle

Feasibility of Commercially Marketed Health Devices for Potential Clinical Application.

Journal

Critical reviews in biomedical engineering · 2020

PMID

31679244

RCR

0.0

Citations

Study type

Primary study

accelerometryadult

Wearable Device Validity in Measuring Steps, Energy Expenditure, and Heart Rate Across Age, Gender, and Body Mass Index: Data Analysis From a Systematic Review.

Journal

Journal of physical activity & health · 2023

PMID

36535270

RCR

1.4

Citations

Study type

Systematic review

humansmale

Fitbit Sense 2 in hospitalized general medicine patients: A pilot study assessing feasibility and validity of specific measures.

Journal

International journal of medical informatics · 2026

PMID

42691870

Citations

Study type

Observational study

adultaged

Conflicting Studies1

Activity trackers are not valid for step count registration when walking with crutches.

Journal

Gait & posture · 2019

PMID

30798092

RCR

0.9

Citations

Study type

Validity study

Bears on

Secondary point

adultarthroplasty, replacement, knee

Retired / Excluded1

Designing wearable computing devices for improved comfort and user acceptance.

Journal

Ergonomics · 2020

PMID

31437415

RCR

0.7

Citations

Study type

Primary study

adultconsumer behavior

Letters, Editorials and Comments (not counted in the rating)1

Navigating the night: evaluating and accessing wearable sleep trackers for clinical use.

Journal

Sleep · 2024

PMID

38097380

Bears on

Secondary point

humanswearable electronic devices

Evidence on: Consumer wearable devices measure energy expenditure with accuracy comparable to reference standards.

21 scored

Anchor Studies4

Reliability and Validity of Commercially Available Wearable Devices for Measuring Steps, Energy Expenditure, and Heart Rate: Systematic Review.

Journal

JMIR mHealth and uHealth · 2021

PMID

32897239

RCR

37.3

Citations

464

Study type

Systematic review

Sample size

n = 158

energy metabolismfitness trackers

Accuracy and Acceptability of Wrist-Wearable Activity-Tracking Devices: Systematic Review of the Literature.

Journal

Journal of medical Internet research · 2022

PMID

35060915

RCR

17.8

Citations

145

Study type

Systematic review

exercisefitness trackers

Keeping Pace with Wearables: A Living Umbrella Review of Systematic Reviews Evaluating the Accuracy of Consumer Wearable Technologies in Health Measurement.

Journal

Sports medicine (Auckland, N.Z.) · 2024

PMID

39080098

RCR

15.1

Citations

Study type

Systematic review

Sample size

n = 249

humansexercise

Accuracy and Precision of Energy Expenditure, Heart Rate, and Steps Measured by Combined-Sensing Fitbits Against Reference Measures: Systematic Review and Meta-analysis.

Journal

JMIR mHealth and uHealth · 2022

PMID

35416777

RCR

7.7

Citations

Study type

Meta-analysis

Sample size

n = 117

accelerometryenergy metabolism

Supporting Studies14

Exercise Intensity and Activity Energy Expenditure of Professional Golf Players in Official Competitive Setting.

Journal

Sports health · 2024

PMID

37278287

RCR

1.1

Citations

Study type

Primary study

humansmale

Comparison of Students' Physical Activity at Different Times and Establishment of a Regression Model for Smart Fitness Trackers.

Journal

Sensors (Basel, Switzerland) · 2025

PMID

40292814

Citations

Study type

Comparative study

humansmale

Comparison of consumer-grade wearable devices with a research-grade instrument for measuring physical activity in a free-living setting.

Journal

PloS one · 2026

PMID

41729926

Citations

Study type

Comparative study

Sample size

n = 21

humanswearable electronic devices

Validity of Galaxy Watch for Estimating Energy Expenditure During Intermittent Running: Cross-Sectional Study.

Journal

JMIR formative research · 2026

PMID

41849635

Citations

Study type

Primary study

Sample size

n = 148

humansenergy metabolism

Validity of four low-cost smartwatches in estimating energy expenditure during cycling in Chinese untrained women.

Journal

PloS one · 2025

PMID

40986546

Citations

Study type

Primary study

adultfemale

Leveraging Accelerometry and Heart Rate Data from Consumer Wearables to Predict Physical Activity in Children: A Device Agnostic Approach.

Journal

Medicine and science in sports and exercise · 2025

PMID

40197719

Citations

Study type

Primary study

humanschild

Developing and comparing a new BMI inclusive energy expenditure algorithm on wrist-worn wearables.

Journal

Scientific reports · 2025

PMID

40537505

Citations

Study type

Comparative study

Sample size

n = 2,189

humansenergy metabolism

Journal

JMIR cardio · 2026

PMID

41027033

Citations

Study type

Validity study

Sample size

57 patients

heart rate determinationenergy metabolism

Consumer Smartwatch Technology in Health and Performance Research: Validity, Limitations, and Real-World Applications.

Journal

Sensors (Basel, Switzerland) · 2026

PMID

42515370

Citations

Study type

Review

humansdigital health

Assessment of laboratory and daily energy expenditure estimates from consumer multi-sensor physical activity monitors.

Journal

PloS one · 2017

PMID

28234979

RCR

5.3

Citations

Study type

Primary study

Sample size

n = 15

accelerometryadult

Improving energy expenditure estimates from wearable devices: A machine learning approach.

Journal

Journal of sports sciences · 2020

PMID

32252598

RCR

2.1

Citations

Study type

Validity study

Sample size

59 subjects

accelerometryactivities of daily living

Validity of Wearable Activity Monitors during Cycling and Resistance Exercise.

Journal

Medicine and science in sports and exercise · 2018

PMID

29189666

RCR

8.0

Citations

132

Study type

Validity study

Sample size

28 women

adultbicycling

Wearable Device Validity in Measuring Steps, Energy Expenditure, and Heart Rate Across Age, Gender, and Body Mass Index: Data Analysis From a Systematic Review.

Journal

Journal of physical activity & health · 2023

PMID

36535270

RCR

1.4

Citations

Study type

Systematic review

humansmale

Validity of a wrist-worn consumer-grade wearable for estimating energy expenditure, sedentary behaviour, and physical activity in manual wheelchair users with spinal cord injury.

Journal

Disability and rehabilitation. Assistive technology · 2025

PMID

39301994

RCR

2.1

Citations

Study type

Validity study

humansspinal cord injuries

Conflicting Studies2

Validity of Activity Trackers in Estimating Energy Expenditure During High-Intensity Functional Training.

Journal

Research quarterly for exercise and sport · 2020

PMID

31046630

RCR

1.9

Citations

Study type

Validity study

Sample size

n = 47

Bears on

Core claim

accelerometryadolescent

Comparative validity of energy expenditure prediction algorithms using wearable devices for people with spinal cord injury.

Journal

Spinal cord · 2021

PMID

32020039

RCR

0.9

Citations

Study type

Validity study

Bears on

Secondary point

actigraphyadult

Letters, Editorials and Comments (not counted in the rating)1

Navigating the night: evaluating and accessing wearable sleep trackers for clinical use.

Journal

Sleep · 2024

PMID

38097380

Bears on

Secondary point

humanswearable electronic devices

Evidence on: Age-predicted maximal-heart-rate equations match an individual’s actual measured maximal heart rate.

2 scored

Anchor Studies2

Age-Predicted Maximal Heart Rate in Recreational Marathon Runners: A Cross-Sectional Study on Fox's and Tanaka's Equations

Journal

Frontiers in Physiology · 2018

PMID

29599724

Sample size

n = 180

Target Heart Rate Formulas for Exercise Stress Testing: What Is the Evidence?

Journal

Journal of Clinical Medicine · 2024

PMID

39337046

Evidence on: A wrist-worn wearable counts steps accurately when a mobility aid is used.

6 scored

Supporting Studies1

Accuracy of Fitbit Devices: Systematic Review and Narrative Syntheses of Quantitative Data

Journal

JMIR mhealth and uhealth · 2018

DOI

10.2196/10527

Citations

686

Study type

Systematic review

Sample size

n = 67

Conflicting Studies3

Accuracy of wearable physical activity trackers in people with Parkinson's disease.

Journal

Gait & posture · 2018

PMID

29729611

RCR

3.7

Citations

Study type

Primary study

Bears on

Secondary point

accelerometryaged

Utilization of wearable technology to assess gait and mobility post-stroke: a systematic review.

Journal

Journal of neuroengineering and rehabilitation · 2021

PMID

33882948

RCR

6.4

Citations

Study type

Systematic review

Bears on

Secondary point

gaithumans

Validation of different stepping counters during treadmill and over ground walking.

Journal

Gait & posture · 2021

PMID

32497979

RCR

0.4

Citations

Study type

Validity study

Bears on

Secondary point

actigraphyadult

Null-Result Studies2

Why your smartwatch may be misleading your doctor: a cross-sectional study on the impact of mobility aids on wearable accuracy in older adults.

Journal

PeerJ · 2026

PMID

42004701

Citations

Study type

Primary study

Bears on

Core claim

humanscross-sectional studies

The Effect of Assistive Devices on the Accuracy of Fitbits in Healthy Individuals: A Brief Report.

Journal

International journal of environmental research and public health · 2025

PMID

40724167

Citations

Study type

Primary study

Sample size

n = 11

Bears on

Core claim

humansmale

Evidence on: Wearable-derived data detects depressive symptoms.

3 scored

Anchor Studies2

Using wearable data to detect depression severity across clinical and non-clinical samples.

Journal

Scientific reports · 2026

PMID

41933099

Citations

Study type

Primary study

Sample size

n = 187

humanswearable electronic devices

Digital Biomarkers for Depression Screening With Wearable Devices: Cross-sectional Study With Machine Learning Modeling.

Journal

JMIR mHealth and uHealth · 2021

PMID

34694233

RCR

8.7

Citations

102

Study type

Primary study

Sample size

n = 170

adultbiomarkers

Supporting Studies1

Use of Mobile Sensing Data for Longitudinal Monitoring and Prediction of Depression Severity: Systematic Review.

Journal

Journal of medical Internet research · 2025

PMID

40839863

RCR

3.3

Citations

Study type

Systematic review

humanssmartphone

01 Research Log

JUL 20 2026

Consumer-Based Wearable Activity Trackers Increase Physical Activity Participation: Systematic Review and Meta-Analysis. (JMIR mHealth and uHealth 2020) entered as anchor on the behavior change claim.

Wearable activity trackers-advanced technology or advanced marketing? (European journal of applied physiology 2022) entered as supporting on the measurement validity claim.

Recommendations for Determining the Validity of Consumer Wearables and Smartphones for the Estimation of Energy Expenditure: Expert Statement and Checklist of the INTERLIVE Network. (Sports medicine (Auckland, N.Z.) 2022) entered as supporting on the measurement validity claim.

Keeping Pace with Wearables: A Living Umbrella Review of Systematic Reviews Evaluating the Accuracy of Consumer Wearable Technologies in Health Measurement. (Sports medicine (Auckland, N.Z.) 2024) entered as anchor on the measurement validity claim.

Using Free-Living Heart Rate Data as an Objective Method to Assess Physical Activity: A Scoping Review and Recommendations by the INTERLIVE-Network Targeting Consumer Wearables. (Sports medicine (Auckland, N.Z.) 2025) entered as supporting on the measurement validity claim.

Is my smartwatch a valid witness? A systematic review and meta-analysis. (Forensic science international 2026) entered as supporting on the measurement validity claim.

Step-count outcomes of 13 different activity trackers: Results from laboratory and free-living experiments. (Gait & posture 2022) entered as supporting on the measurement validity claim.

Validity of Apple Watch 6 and Polar A370 for monitoring energy expenditure while resting or performing light to vigorous physical activity. (Journal of science and medicine in sport 2023) entered as supporting on the measurement validity claim.

The validity and reliability of consumer-grade activity trackers in older, community-dwelling adults: A systematic review. (Maturitas 2018) entered as supporting on the measurement validity claim.

Sensing leg movement enhances wearable monitoring of energy expenditure. (Nature communications 2021) entered as supporting on the measurement validity claim.

Validity of Wrist-Worn photoplethysmography devices to measure heart rate: A systematic review and meta-analysis. (Journal of sports sciences 2020) entered as anchor on the measurement validity claim.

Factors associated with validity of consumer-oriented wearable physical activity trackers: a meta-analysis. (Journal of medical engineering & technology 2021) entered as supporting on the measurement validity claim.

A meta-analysis of Fitbit devices: same company, different models, different validity evidence. (Journal of medical engineering & technology 2022) entered as supporting on the measurement validity claim.

Wrist-worn devices for the measurement of heart rate and energy expenditure: A validation study for the Apple Watch 6, Polar Vantage V and Fitbit Sense. (European journal of sport science 2023) entered as supporting on the measurement validity claim.

Apple watch accuracy in monitoring health metrics: a systematic review and meta-analysis. (Physiological measurement 2025) entered as supporting on the measurement validity claim.

Accuracy of energy expenditure estimation by the Apple Watch in EMS-supported exercise. (Physiological measurement 2025) entered as supporting on the measurement validity claim.

Validation of a novel multi-sensor wearable for measuring heart rate, steps, and energy expenditure in laboratory and simulated free-living protocols. (Physiological measurement 2026) entered as supporting on the measurement validity claim.

Benchmarking open-source step counting algorithms for wrist-worn devices. (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 of energy expenditure estimation methods during 10 days of military training. (Scandinavian journal of medicine & science in sports 2019) entered as supporting on the measurement validity claim.

Recommendations for determining the validity of consumer wearable and smartphone step count: expert statement and checklist of the INTERLIVE network. (British journal of sports medicine 2021) entered as supporting on the measurement validity claim.

Validation of a wireless device-driven method of estimating caloric expenditure during running. (Applied physiology, nutrition, and metabolism = Physiologie appliquee, nutrition et metabolisme 2026) entered as supporting on the measurement validity claim.

Fitness band accuracy in older community dwelling adults. (Health informatics journal 2020) entered as supporting on the measurement validity claim.

A catalog of validity indices for step counting wearable technologies during treadmill walking: the CADENCE-adults study. (The international journal of behavioral nutrition and physical activity 2022) entered as supporting on the measurement validity claim.

Assessment of 24-hour physical behaviour in adults via wearables: a systematic review of validation studies under laboratory conditions. (The international journal of behavioral nutrition and physical activity 2023) entered as supporting on the measurement validity claim.

Standardizing Analytic Methods and Reporting in Activity Monitor Validation Studies. (Medicine and science in sports and exercise 2020) entered as supporting on the measurement validity claim.

Performance Evaluation of Device-Based Algorithms to Estimate Step Counts in Free-Living Adults Compared with Direct Observation. (Medicine and science in sports and exercise 2026) entered as supporting on the measurement validity claim.

Validity of four low-cost smartwatches in estimating energy expenditure during cycling in Chinese untrained women. (PloS one 2025) entered as supporting on the measurement validity claim.

Accurate measurement of simulated slow and altered walking activity: Apple Watch best in class wearable devices. (PloS one 2025) entered as supporting on the measurement validity claim.

Comparison of consumer-grade wearable devices with a research-grade instrument for measuring physical activity in a free-living setting. (PloS one 2026) entered as supporting on the measurement validity claim.

Accuracy of the Multisensory Wristwatch Polar Vantage's Estimation of Energy Expenditure in Various Activities: Instrument Validation Study. (JMIR mHealth and uHealth 2020) entered as supporting on the measurement validity claim.

Reliability and Validity of Commercially Available Wearable Devices for Measuring Steps, Energy Expenditure, and Heart Rate: Systematic Review. (JMIR mHealth and uHealth 2021) entered as anchor on the measurement validity claim.

Accuracy and Acceptability of Wrist-Wearable Activity-Tracking Devices: Systematic Review of the Literature. (Journal of medical Internet research 2022) entered as anchor on the measurement validity claim.

Accuracy and Precision of Energy Expenditure, Heart Rate, and Steps Measured by Combined-Sensing Fitbits Against Reference Measures: Systematic Review and Meta-analysis. (JMIR mHealth and uHealth 2022) entered as anchor on the measurement validity claim.

Quality Evaluation of Free-living Validation Studies for the Assessment of 24-Hour Physical Behavior in Adults via Wearables: Systematic Review. (JMIR mHealth and uHealth 2022) entered as supporting on the measurement validity claim.

Raw Photoplethysmography as an Enhancement for Research-Grade Wearable Activity Monitors. (JMIR mHealth and uHealth 2024) entered as supporting on the measurement validity claim.

Validation of steps countering recorded with a smartwatch. (The Journal of sports medicine and physical fitness 2024) entered as supporting on the measurement validity claim.

Validity of Wrist-Worn Activity Trackers for Estimating VO 2max and Energy Expenditure. (International journal of environmental research and public health 2020) entered as supporting on the measurement validity claim.

Validation of an Open-Source Smartwatch for Continuous Monitoring of Physical Activity and Heart Rate in Adults. (Sensors (Basel, Switzerland) 2025) entered as supporting on the measurement validity claim.

Aggregation Periods Influence Step Count Error in Low-Power Wearables. (Sensors (Basel, Switzerland) 2025) entered as supporting on the measurement validity claim.

Are Wrist-Worn Activity Trackers and Mobile Applications Valid for Assessing Physical Activity in High School Students? Wearfit Study. (Journal of sports science & medicine 2022) entered as supporting on the measurement validity claim.

Criterion-Related Validity of Consumer-Wearable Activity Trackers for Estimating Steps in Primary Schoolchildren under Controlled Conditions: Fit-Person Study. (Journal of sports science & medicine 2024) entered as supporting on the measurement validity claim.

Wearable-device-measured physical activity and future health risk. (Nature medicine 2020) entered as anchor on the physiological claim.

JUL 20 2026

Wearable activity trackers-advanced technology or advanced marketing? (European journal of applied physiology 2022) entered as supporting on the device motion validity claim.

Is my smartwatch a valid witness? A systematic review and meta-analysis. (Forensic science international 2026) entered as supporting on the device motion validity claim.

Step-count outcomes of 13 different activity trackers: Results from laboratory and free-living experiments. (Gait & posture 2022) entered as supporting on the device motion validity claim.

The validity and reliability of consumer-grade activity trackers in older, community-dwelling adults: A systematic review. (Maturitas 2018) entered as supporting on the device motion validity claim.

Sensing leg movement enhances wearable monitoring of energy expenditure. (Nature communications 2021) entered as supporting on the device motion validity claim.

Validity of Wrist-Worn photoplethysmography devices to measure heart rate: A systematic review and meta-analysis. (Journal of sports sciences 2020) entered as anchor on the device motion validity claim.

Apple watch accuracy in monitoring health metrics: a systematic review and meta-analysis. (Physiological measurement 2025) entered as supporting on the device motion validity claim.

Accuracy of energy expenditure estimation by the Apple Watch in EMS-supported exercise. (Physiological measurement 2025) entered as supporting on the device motion validity claim.

Fitness band accuracy in older community dwelling adults. (Health informatics journal 2020) entered as supporting on the device motion validity claim.

Standardizing Analytic Methods and Reporting in Activity Monitor Validation Studies. (Medicine and science in sports and exercise 2020) entered as supporting on the device motion validity claim.

Validity of four low-cost smartwatches in estimating energy expenditure during cycling in Chinese untrained women. (PloS one 2025) entered as supporting on the device motion validity claim.

Accurate measurement of simulated slow and altered walking activity: Apple Watch best in class wearable devices. (PloS one 2025) entered as supporting on the device motion validity claim.

Raw Photoplethysmography as an Enhancement for Research-Grade Wearable Activity Monitors. (JMIR mHealth and uHealth 2024) entered as supporting on the device motion validity claim.

Validation of steps countering recorded with a smartwatch. (The Journal of sports medicine and physical fitness 2024) entered as supporting on the device motion validity claim.

Aggregation Periods Influence Step Count Error in Low-Power Wearables. (Sensors (Basel, Switzerland) 2025) entered as supporting on the device motion validity claim.

Age-Predicted Maximal Heart Rate in Recreational Marathon Runners: A Cross-Sectional Study on Fox's and Tanaka's Equations (Frontiers in Physiology 2018) entered as anchor on the max heart rate formula validity claim.

Target Heart Rate Formulas for Exercise Stress Testing: What Is the Evidence? (Journal of Clinical Medicine 2024) entered as anchor on the max heart rate formula validity claim.

JUL 20 2026

Manual restructuring: genesis founded a single combined "measurement-validity" claim (steps + heart rate + energy expenditure). Split into device-motion-validity and energy-expenditure-validity because the anchor evidence itself draws a clear line: energy-expenditure accuracy is consistently and specifically worse than step/heart-rate accuracy across every anchor, and a combined claim risked understating that finding under one averaged rung.

max-heart-rate-formula-validity founded from 2 manually-seeded, individually-verified papers (not the automated crawl) -- exercise-physiology literature on age-predicted HRmax formulas (220-minus-age, Fox, Tanaka) is not indexed under this cluster's wearable-device MeSH anchors.

JUL 24 2026

Editorial: Wearable Sensors for Remote Health Monitoring and Intelligent Disease Management. (Frontiers in sports and active living 2021) entered as conflicting on the behavior change claim.

Navigating the night: evaluating and accessing wearable sleep trackers for clinical use. (Sleep 2024) entered as conflicting on the device motion validity claim.

Navigating the night: evaluating and accessing wearable sleep trackers for clinical use. (Sleep 2024) entered as conflicting on the energy expenditure validity claim.

Quantifying population levels of physical activity in Africa using wearable sensors: implications for global physical activity surveillance. (BMJ open sport & exercise medicine 2026) entered as conflicting on the physiological claim.

Device-measured physical activity and type 2 diabetes mellitus risk. (Frontiers in endocrinology 2024) entered as conflicting on the physiological claim.

Beyond the snapshot: harnessing daily physical activity for heart failure characterization. (Clinical research in cardiology : official journal of the German Cardiac Society 2025) entered as conflicting on the physiological claim.

JUL 24 2026

Editorial: Wearable Sensors for Remote Health Monitoring and Intelligent Disease Management. (Frontiers in sports and active living 2021) entered as a conflicting study on the behavior change 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 24 2026

Navigating the night: evaluating and accessing wearable sleep trackers for clinical use. (Sleep 2024) entered as a conflicting study on the device motion 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 24 2026

Navigating the night: evaluating and accessing wearable sleep trackers for clinical use. (Sleep 2024) entered as a conflicting study on the energy expenditure 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 24 2026

Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.

JUL 24 2026

Device-measured physical activity and type 2 diabetes mellitus risk. (Frontiers in endocrinology 2024) entered as a conflicting 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 24 2026

Because it does not hit the core claim, it does not cap the rating and is tracked as an open question.

AUG 14 2026

Wearable technology for mobility measurement in orthopedics and traumatology: a comparison of commercially available systems. (Archives of orthopaedic and trauma surgery 2025) entered as supporting on the device motion validity claim.

Accuracy of wearable physical activity trackers in people with Parkinson's disease. (Gait & posture 2018) entered as supporting on the device motion validity claim.

Step count accuracy and reliability of two activity tracking devices in people after stroke. (Physiotherapy theory and practice 2018) entered as supporting on the device motion validity claim.

Validity of a Consumer-Based Wearable to Measure Clinical Parameters in Patients With Chronic Obstructive Pulmonary Disease and Healthy Controls: Observational Study. (JMIR mHealth and uHealth 2024) entered as supporting on the device motion validity claim.

The Effect of Assistive Devices on the Accuracy of Fitbits in Healthy Individuals: A Brief Report. (International journal of environmental research and public health 2025) entered as supporting on the device motion validity claim.

Comparison of Students' Physical Activity at Different Times and Establishment of a Regression Model for Smart Fitness Trackers. (Sensors (Basel, Switzerland) 2025) entered as supporting on the device motion validity claim.

Consumer Smartwatch Technology in Health and Performance Research: Validity, Limitations, and Real-World Applications. (Sensors (Basel, Switzerland) 2026) entered as supporting on the device motion validity claim.

Developing and comparing a new BMI inclusive energy expenditure algorithm on wrist-worn wearables. (Scientific reports 2025) entered as supporting on the energy expenditure validity claim.

Exercise Intensity and Activity Energy Expenditure of Professional Golf Players in Official Competitive Setting. (Sports health 2024) entered as supporting on the energy expenditure validity claim.

Leveraging Accelerometry and Heart Rate Data from Consumer Wearables to Predict Physical Activity in Children: A Device Agnostic Approach. (Medicine and science in sports and exercise 2025) entered as supporting on the energy expenditure validity claim.

Validity of four low-cost smartwatches in estimating energy expenditure during cycling in Chinese untrained women. (PloS one 2025) entered as supporting on the energy expenditure validity claim.

Validity of Galaxy Watch for Estimating Energy Expenditure During Intermittent Running: Cross-Sectional Study. (JMIR formative research 2026) entered as supporting on the energy expenditure validity claim.

Association of Perioperative Steps and Heart Rate Variability from Wearable Devices with Surgical Outcomes. (Journal of the American College of Surgeons 2026) entered as supporting on the physiological claim.

Impact of Extravalvular Remodeling on Wearable Smartwatch-Recorded Physical Activity in Patients Undergoing Transcatheter Aortic Valve Implantation for Severe Symptomatic Aortic Stenosis. (Journal of the American Heart Association 2026) entered as supporting on the physiological claim.

Predicting incident type 2 diabetes using wearable activity and polygenic risk: A survival-modeling study in All of Us. (The Journal of clinical endocrinology and metabolism 2026) entered as supporting on the physiological claim.

Digital Biomarkers for Depression Screening With Wearable Devices: Cross-sectional Study With Machine Learning Modeling. (JMIR mHealth and uHealth 2021) entered as supporting on the physiological claim.

Preoperative Decline and Postoperative Recovery of Wearable-Derived Physical Activity over a Four-Year Perioperative Period in Total Knee and Hip Arthroplasty. (Sensors (Basel, Switzerland) 2026) entered as supporting on the physiological claim.

AUG 21 2026

A Web-Based Pedometer-Mediated Intervention Maintains Benefits After Pulmonary Rehabilitation: A Pilot Study. (International journal of chronic obstructive pulmonary disease 2026) entered as supporting on the behavior change claim.

Designing wearable computing devices for improved comfort and user acceptance. (Ergonomics 2020) entered as retired on the device motion validity claim.

Validity and Reliability Evaluation of Four Commercial Activity Trackers' Step Counting Performance. (Telemedicine journal and e-health : the official journal of the American Telemedicine Association 2019) entered as supporting on the device motion validity claim.

Step count accuracy of StepWatch and FitBit One™ among individuals with a unilateral transtibial amputation. (Prosthetics and orthotics international 2019) entered as supporting on the device motion validity claim.

Improving energy expenditure estimates from wearable devices: A machine learning approach. (Journal of sports sciences 2020) entered as supporting on the energy expenditure validity claim.

Assessment of laboratory and daily energy expenditure estimates from consumer multi-sensor physical activity monitors. (PloS one 2017) entered as supporting on the energy expenditure validity claim.

Association Between Wearable Device Measured Activity and Patient-Reported Outcomes for Heart Failure. (JACC. Heart failure 2023) entered as supporting on the physiological claim.

Validity of energy expenditure estimation methods during 10 days of military training. (Scandinavian journal of medicine & science in sports 2019) entered as retired on the physiological claim.

SEP 4 2026

Activity trackers are not valid for step count registration when walking with crutches. (Gait & posture 2019) entered as conflicting on the device motion validity claim.

Assessment of step accuracy using the Consumer Technology Association standard. (Journal of sports sciences 2019) entered as supporting on the device motion validity claim.

Validity of the "Samsung Health" application to measure steps: A study with two different samsung smartphones. (Journal of sports sciences 2019) entered as supporting on the device motion validity claim.

Validity of Wearable Activity Monitors during Cycling and Resistance Exercise. (Medicine and science in sports and exercise 2018) entered as supporting on the device motion validity claim.

Validity of Activity Trackers in Estimating Energy Expenditure During High-Intensity Functional Training. (Research quarterly for exercise and sport 2020) entered as conflicting on the energy expenditure validity claim.

Validity of Wearable Activity Monitors during Cycling and Resistance Exercise. (Medicine and science in sports and exercise 2018) entered as supporting on the energy expenditure validity claim.

Device-Measured Sleep Characteristics, Daily Step Count, and Cardiometabolic Health Markers: Findings From the Prospective Physical Activity, Sitting, and Sleep (ProPASS) Consortium. (Circulation. Cardiovascular quality and outcomes 2025) entered as supporting on the physiological claim.

SEP 4 2026

Activity trackers are not valid for step count registration when walking with crutches. (Gait & posture 2019) entered as a conflicting study on the device motion 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.

SEP 4 2026

Validity of Activity Trackers in Estimating Energy Expenditure During High-Intensity Functional Training. (Research quarterly for exercise and sport 2020) entered as a conflicting study on the energy expenditure validity claim, bearing on the core claim.

It caps the rating until reconciled.

SEP 17 2026

The use of artificial intelligence and wearable devices in enhanced recovery after surgery pathways following radical cystectomy: A systematic review. (The Journal of international medical research 2026) entered as supporting on the behavior change claim.

Feasibility of Commercially Marketed Health Devices for Potential Clinical Application. (Critical reviews in biomedical engineering 2020) entered as supporting on the device motion validity claim.

A Step in the Right Direction: Body Location Determines Activity Tracking Device Accuracy in Total Knee and Hip Arthroplasty Patients. (The Journal of the American Academy of Orthopaedic Surgeons 2020) entered as supporting on the device motion validity claim.

SEP 30 2026

Accuracy of wearable physical activity trackers in people with Parkinson's disease. (Gait & posture 2018) entered as conflicting on the atypical_gait_steps claim.

Why your smartwatch may be misleading your doctor: a cross-sectional study on the impact of mobility aids on wearable accuracy in older adults. (PeerJ 2026) entered as null_result on the atypical_gait_steps claim.

SEP 30 2026

Accuracy of wearable physical activity trackers in people with Parkinson's disease. (Gait & posture 2018) entered as a conflicting study on the atypical_gait_steps 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

It caps the rating until reconciled.

SEP 30 2026

Why your smartwatch may be misleading your doctor: a cross-sectional study on the impact of mobility aids on wearable accuracy in older adults. (PeerJ 2026) entered as a null result study on the atypical_gait_steps claim, bearing on the core claim.

It caps the rating until reconciled.

SEP 30 2026

Using wearable data to detect depression severity across clinical and non-clinical samples. (Scientific reports 2026) entered as anchor on the depression_detection claim.

Digital Biomarkers for Depression Screening With Wearable Devices: Cross-sectional Study With Machine Learning Modeling. (JMIR mHealth and uHealth 2021) entered as anchor on the depression_detection claim.

Use of Mobile Sensing Data for Longitudinal Monitoring and Prediction of Depression Severity: Systematic Review. (Journal of medical Internet research 2025) entered as supporting on the depression_detection claim.

SEP 30 2026

Accuracy of Fitbit Devices: Systematic Review and Narrative Syntheses of Quantitative Data (JMIR mhealth and uhealth 2018) entered as supporting on the atypical_gait_steps claim.

OCT 2 2026

Using wearable data to detect depression severity across clinical and non-clinical samples. (Scientific reports 2026) entered as anchor on the depression_detection claim.

OCT 7 2026

Validation of different stepping counters during treadmill and over ground walking. (Gait & posture 2021) entered as conflicting on the atypical_gait_steps claim.

Utilization of wearable technology to assess gait and mobility post-stroke: a systematic review. (Journal of neuroengineering and rehabilitation 2021) entered as conflicting on the atypical_gait_steps claim.

Activity monitors for increasing physical activity in adult stroke survivors. (The Cochrane database of systematic reviews 2018) entered as conflicting on the behavior change claim.

Use of commercially available wearable devices for physical rehabilitation in healthcare: a systematic review. (BMJ open 2024) entered as supporting on the behavior change claim.

A Web-Based, Pedometer-Mediated Intervention Increases Amount and Intensity of Physical Activity in COPD: A Randomized Controlled Trial. (International journal of chronic obstructive pulmonary disease 2026) entered as supporting on the behavior change claim.

Wearable Device Validity in Measuring Steps, Energy Expenditure, and Heart Rate Across Age, Gender, and Body Mass Index: Data Analysis From a Systematic Review. (Journal of physical activity & health 2023) entered as supporting on the device motion validity claim.

Comparative validity of energy expenditure prediction algorithms using wearable devices for people with spinal cord injury. (Spinal cord 2021) entered as conflicting on the energy expenditure validity claim.

Validity of a wrist-worn consumer-grade wearable for estimating energy expenditure, sedentary behaviour, and physical activity in manual wheelchair users with spinal cord injury. (Disability and rehabilitation. Assistive technology 2025) entered as supporting on the energy expenditure validity claim.

Daily Step Counts for Measuring Physical Activity Exposure and Its Relation to Health. (Medicine and science in sports and exercise 2019) entered as anchor on the physiological claim.

OCT 7 2026

Validation of different stepping counters during treadmill and over ground walking. (Gait & posture 2021) entered as a conflicting study on the atypical_gait_steps 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 7 2026

Utilization of wearable technology to assess gait and mobility post-stroke: a systematic review. (Journal of neuroengineering and rehabilitation 2021) entered as a conflicting study on the atypical_gait_steps 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 7 2026

Activity monitors for increasing physical activity in adult stroke survivors. (The Cochrane database of systematic reviews 2018) entered as a conflicting study on the behavior change 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 7 2026

Comparative validity of energy expenditure prediction algorithms using wearable devices for people with spinal cord injury. (Spinal cord 2021) entered as a conflicting study on the energy expenditure 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

Effectiveness of Minimal Contact Interventions: An RCT. (American journal of preventive medicine 2021) entered as null_result on the behavior change claim.

Fitbit Sense 2 in hospitalized general medicine patients: A pilot study assessing feasibility and validity of specific measures. (International journal of medical informatics 2026) entered as supporting on the device motion validity claim.

OCT 15 2026

Effectiveness of Minimal Contact Interventions: An RCT. (American journal of preventive medicine 2021) entered as a null result study on the behavior change claim, bearing on the core claim.

It caps the rating until reconciled.

02 Revision Log

OCT 15 2026

behavior change: Emerging → Uncertain

Moved to Uncertain by rule from the current evidence for: Wearable activity tracker use increases physical activity participation..

OCT 2 2026

depression_detection: Emerging → Uncertain

Moved to Uncertain by rule from the current evidence for: Wearable-derived data detects depressive symptoms..

SEP 30 2026

depression_detection: opened at Emerging

Opened at Emerging by rule from the current evidence for: Wearable-derived data detects depressive symptoms..

SEP 30 2026

atypical_gait_steps: opened at Unsupported

Opened at Unsupported by rule from the current evidence for: A wrist-worn wearable counts steps accurately when a mobility aid is used or gait is slow..

JUL 20 2026

max heart rate formula validity: opened at Uncertain

Opened at Uncertain by rule from the current evidence for: Age-predicted maximal-heart-rate equations match an individual’s actual measured maximal heart rate..

JUL 20 2026

energy expenditure validity: opened at Uncertain

Opened at Uncertain by rule from the current evidence for: Consumer wearable devices measure energy expenditure with accuracy comparable to reference standards..

JUL 20 2026

device motion validity: opened at Established

Opened at Established by rule from the current evidence for: Consumer wearable devices measure step count and heart rate with accuracy comparable to reference standards..

JUL 20 2026

behavior change: opened at Emerging

Opened at Emerging by rule from the current evidence for: Wearable activity tracker use increases physical activity participation..

JUL 20 2026

physiological: opened at Emerging

Opened at Emerging by rule from the current evidence for: Higher wearable-measured physical activity is associated with lower all-cause mortality risk..

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.