KnowYourPrime Evidence Registry · Finding KYP-ER-0015

VO2 Max by Age and Sex: US Reference Standards

Question assessedWhat is a normal or good VO2 max for my age and sex?

KnowYourPrime evidence ratingEstablishedStrong, consistent evidence supports the claim.

US reference standards from more than 22,000 laboratory tests give VO2 max percentiles for every decade from 20 to 89, for men and women and for treadmill and cycle tests. Across those 22,379 tests the median fell by an average of 13.5 percent per decade on treadmill and 16.4 percent on cycle, so a good value depends heavily on age, and which reference set is used can change where a person lands.

Finding KYP-ER-0015Version 1.1Reviewed October 24, 2026Rating rule 1.6CC BY 4.0

Why this is rated Established

Two anchor studies from the US Fitness Registry and the Importance of Exercise National Database (FRIEND) built the percentiles this question is usually answered with, and both affirm the age decline, which rates the claim Established.

Three studies add a real limit on how the percentiles are used: no single reference set fits every population, common equations underestimated measured fitness in healthy 50-year-old women, and the same test result can be classed as reduced or normal depending on which equation is used.

How the rating rule reads this evidence

Anchor-grade evidence affirms the core relationship.
Some evidence conflicts on secondary points that do not change the core direction.

Key results

From 22,379 maximal tests in apparently healthy US adults aged 20 to 89 (16,278 treadmill, 6,101 cycle), the 50th percentile fell with age in both sexes and both modes, by an average of 13.5 percent per decade on treadmill and 16.4 percent on cycle, and was higher in men at every age. (Kaminsky et al., Mayo Clinic Proceedings, 2022)
The first FRIEND standards, from 7,783 treadmill tests, put the 50th percentile at 48.0 and 37.6 mL/kg/min for men and women aged 20 to 29 and 24.4 and 18.3 for ages 70 to 79, a decline of about 10 percent per decade. (Kaminsky et al., Mayo Clinic Proceedings, 2016)
Scored against seven prediction equations, 332 adults’ mean percent-predicted ranged from 83 to 113 percent and the share classed as reduced from 7 to 51 percent, depending on the equation. (Kaboudan et al., Medicine and Science in Sports and Exercise, 2026)

What this finding covers

Applies to: VO2 max measured by cardiopulmonary exercise testing in apparently healthy US adults, by age, sex and test mode.

Does not cover: Watch estimates of VO2 max, which differ from lab values (see the related finding); people with cardiovascular disease; whether VO2 max predicts lifespan.

Limitations

The registry draws on volunteers tested at US laboratories, which may not represent the whole population.
Treadmill values run higher than cycle values, so a percentile must be read against the right mode.
A watch estimate placed on these lab percentiles can misplace a person by several percentile bands.

Evidence base

6 studies scored · 2 anchor · 3 conflicting · 1 supporting · Evidence last evaluated Oct 17, 2026

Anchor studies

The studies the rating rests on.

Updated Reference Standards for Cardiorespiratory Fitness Measured with Cardiopulmonary Exercise Testing: Data from the Fitness Registry and the Importance of Exercise National Database (FRIEND).Kaminsky et al., Mayo Clinic Proceedings, 2022. doi.org/10.1016/j.mayocp.2021.08.020
Reference Standards for Cardiorespiratory Fitness Measured With Cardiopulmonary Exercise Testing: Data From the Fitness Registry and the Importance of Exercise National Database.Kaminsky et al., Mayo Clinic Proceedings, 2016. doi.org/10.1016/j.mayocp.2015.07.026

Conflicting studies

Studies whose findings run against the claim.

Determinants of Reclassification of Exercise Performance across Cardiopulmonary Exercise Testing Prediction Equations.Kaboudan et al., Medicine and Science in Sports and Exercise, 2026. doi.org/10.1249/MSS.0000000000004065
Commonly used reference values underestimate oxygen uptake in healthy, 50-year-old Swedish women.Genberg et al., Clinical Physiology and Functional Imaging, 2018. doi.org/10.1111/cpf.12377
Reference values for cardiopulmonary exercise testing in healthy adults: a systematic review.Paap et al., Expert Review of Cardiovascular Therapy, 2015. doi.org/10.1586/14779072.2014.985657

Supporting studies

Studies consistent with the claim that do not carry the rating on their own.

Size Exponents for Scaling Maximal Oxygen Uptake in Over 6500 Humans: A Systematic Review and Meta-Analysis.Lolli et al., Sports Medicine, 2018. doi.org/10.1007/s40279-016-0655-1

Version history

Version	Date	Rating	Change
1.0	October 24, 2026	Established	First published.
1.1	October 24, 2026	Established	Opening restores the per-decade decline with its 22,379-test base.

Rating history on the research desk: Established (October 3, 2026).

Cite this finding

KnowYourPrime Evidence Registry, Finding KYP-ER-0015, version 1.1, reviewed 2026-10-24. https://knowyourprime.com/evidence-vo2-max-by-age-reference

Machine-readable: JSON · Markdown · All findings

Research desk: the VO2 max research desk entry for this question, with every scored study and its role
Related finding: Wearable VO2 Max Estimate Accuracy (KYP-ER-0011)
On this site: VO2 Max by Age: What's a Good Score for Men and Women?
On this site: What Is a Good VO2 Max for a 40 Year Old? Percentiles for Men and Women
On this site: What Is a Good VO2 Max for a 50 Year Old? Percentiles for Men and Women
On this site: What Is a Good VO2 Max for a 60 Year Old? Percentiles for Men and Women
On this site: What Is a Good VO2 Max for a 70 Year Old? Percentiles and the Survival Threshold

This is KnowYourPrime's own assessment of the published evidence, rated under the KnowYourPrime evidence methodology. The rating is set by a fixed rule from the roles of the studies above and moves only when the evidence or the rule changes. Every change to the rating or the text is published as a new dated version. To report an error, write to corrections@knowyourprime.com.