{ "registry": "KnowYourPrime Evidence Registry", "license": { "name": "CC BY 4.0", "url": "https://creativecommons.org/licenses/by/4.0/", "attribution": "Credit KnowYourPrime and link to the finding URL." }, "fields": { "devices": "Devices this finding names, including models it says it does not cover. What was actually tested is in scope.applies_to; exclusions are in scope.does_not_cover.", "evidence": "Studies by role: anchor (the rating rests on it), conflicting, null_result, supporting.", "industry_ties": "Device-maker ties listed in Europe PMC metadata: author_affiliations names makers an author lists as an affiliation, funders names makers listed as funding. stated_ties holds ties a paper states only in its own conflict, funding or acknowledgement text, each read from that statement and worded to say only what it says. Sources are Europe PMC metadata, funding printed in the abstract, and those reviewed statements. An empty list means no tie was found there, not that the study is independent: many papers have no open full text to read. Metadata, not a judgment of the study. checked false means no Europe PMC metadata was available." }, "id": "KYP-ER-0015", "version": "1.1", "reviewed": "2026-10-24", "url": "https://knowyourprime.com/evidence-vo2-max-by-age-reference", "title": "VO2 Max by Age and Sex: US Reference Standards", "question": "What is a normal or good VO2 max for my age and sex?", "measurement": "VO2 max (cardio fitness)", "devices": [ "Apple Watch", "Garmin", "Fitbit", "Lab testing" ], "rating": { "label": "Established", "code": "established", "definition": "Strong, consistent evidence supports the claim.", "rule_version": "1.6", "rule_reasons": [ "Anchor-grade evidence affirms the core relationship.", "Some evidence conflicts on secondary points that do not change the core direction." ] }, "conclusion": "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.", "reasoning": [ "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." ], "key_results": [ { "text": "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.", "source": "doi:10.1016/j.mayocp.2021.08.020", "source_url": "https://doi.org/10.1016/j.mayocp.2021.08.020", "source_citation": "Kaminsky et al., Mayo Clinic Proceedings, 2022" }, { "text": "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.", "source": "doi:10.1016/j.mayocp.2015.07.026", "source_url": "https://doi.org/10.1016/j.mayocp.2015.07.026", "source_citation": "Kaminsky et al., Mayo Clinic Proceedings, 2016" }, { "text": "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.", "source": "doi:10.1249/mss.0000000000004065", "source_url": "https://doi.org/10.1249/MSS.0000000000004065", "source_citation": "Kaboudan et al., Medicine and Science in Sports and Exercise, 2026" } ], "scope": { "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": { "anchor": [ { "key": "doi:10.1016/j.mayocp.2021.08.020", "title": "Updated Reference Standards for Cardiorespiratory Fitness Measured with Cardiopulmonary Exercise Testing: Data from the Fitness Registry and the Importance of Exercise National Database (FRIEND).", "first_author": "Kaminsky", "journal": "Mayo Clinic proceedings", "year": 2022, "url": "https://doi.org/10.1016/j.mayocp.2021.08.020", "industry_ties": { "checked": true, "author_affiliations": [], "funders": [], "stated_ties": [] } }, { "key": "doi:10.1016/j.mayocp.2015.07.026", "title": "Reference Standards for Cardiorespiratory Fitness Measured With Cardiopulmonary Exercise Testing: Data From the Fitness Registry and the Importance of Exercise National Database.", "first_author": "Kaminsky", "journal": "Mayo Clinic proceedings", "year": 2016, "url": "https://doi.org/10.1016/j.mayocp.2015.07.026", "industry_ties": { "checked": true, "author_affiliations": [], "funders": [], "stated_ties": [] } } ], "conflicting": [ { "key": "doi:10.1249/mss.0000000000004065", "title": "Determinants of Reclassification of Exercise Performance across Cardiopulmonary Exercise Testing Prediction Equations.", "first_author": "Abbaspour Kaboudan", "journal": "Medicine and science in sports and exercise", "year": 2026, "url": "https://doi.org/10.1249/MSS.0000000000004065", "industry_ties": { "checked": true, "author_affiliations": [], "funders": [], "stated_ties": [] } }, { "key": "doi:10.1111/cpf.12377", "title": "Commonly used reference values underestimate oxygen uptake in healthy, 50-year-old Swedish women.", "first_author": "Genberg", "journal": "Clinical physiology and functional imaging", "year": 2018, "url": "https://doi.org/10.1111/cpf.12377", "industry_ties": { "checked": true, "author_affiliations": [], "funders": [], "stated_ties": [] } }, { "key": "doi:10.1586/14779072.2014.985657", "title": "Reference values for cardiopulmonary exercise testing in healthy adults: a systematic review.", "first_author": "Paap", "journal": "Expert review of cardiovascular therapy", "year": 2015, "url": "https://doi.org/10.1586/14779072.2014.985657", "industry_ties": { "checked": true, "author_affiliations": [], "funders": [], "stated_ties": [] } } ], "supporting": [ { "key": "doi:10.1007/s40279-016-0655-1", "title": "Size Exponents for Scaling Maximal Oxygen Uptake in Over 6500 Humans: A Systematic Review and Meta-Analysis.", "first_author": "Lolli", "journal": "Sports medicine (Auckland, N.Z.)", "year": 2018, "url": "https://doi.org/10.1007/s40279-016-0655-1", "industry_ties": { "checked": true, "author_affiliations": [], "funders": [], "stated_ties": [] } } ] }, "evidence_last_evaluated": "Oct 17, 2026", "rating_history": [ { "date": "2026-10-03", "rating": "Established", "from": null, "rule_version": "1.6" } ], "versions": [ { "version": "1.0", "date": "2026-10-24", "rating": "Established", "change": "First published." }, { "version": "1.1", "date": "2026-10-24", "rating": "Established", "change": "Opening restores the per-decade decline with its 22,379-test base." } ], "research_desk": "https://knowyourprime.com/research-desk-vo2max#normative_by_age_sex", "related_findings": [ "https://knowyourprime.com/evidence-wearable-vo2-max-accuracy" ], "related_articles": [ "https://knowyourprime.com/vo2-max-by-age", "https://knowyourprime.com/good-vo2-max-for-40-year-old", "https://knowyourprime.com/good-vo2-max-for-50-year-old", "https://knowyourprime.com/good-vo2-max-for-60-year-old", "https://knowyourprime.com/good-vo2-max-for-70-year-old" ], "methodology": "https://knowyourprime.com/methodology", "citation": "KnowYourPrime Evidence Registry, Finding KYP-ER-0015, version 1.1, reviewed 2026-10-24. https://knowyourprime.com/evidence-vo2-max-by-age-reference" }