VO2 Max Calculator (Rockport Walk Test)
- Calculator
- About 3 min
- Rockport one-mile walk equation, Kline 1987
- Runs in your browser, nothing is sent
- Medical review: Medical review pending
What this calculator works out
VO2 max is the most oxygen your body can use per minute during hard exercise, expressed per kilogram of body weight. It is the single fitness number most strongly tied to how long people live, and a brisk walk with a heart rate reading is enough to estimate it.
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Your estimated VO2 max
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Where it sits for your age and sex
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What one point of change is worth
How this compares with a typical online quiz
| Feature | Typical free quiz | Regenerated.com |
|---|---|---|
| Published equation named | Rarely | Kline, Porcari, Hintermeister and colleagues, 1987 |
| Error margin stated | No | Yes, the standard error of about 5 mL/kg/min |
| Age and sex norms cited | Unsourced tables | FRIEND registry, measured treadmill tests |
| Other field tests explained | Mixed into one score | Cooper run and heart rate ratio described separately |
| Weight in lb or kg | One or the other | Either, conversion in the help text |
| Answers sent to a server | Often | Never; scored in your browser, counts-only events |
How to do the one-mile walk test properly
Pick a flat, measured mile: four laps of a standard 400 meter running track is 1,600 meters, close enough, or use a GPS watch on a level path. Warm up for five minutes at an easy pace. Then walk the mile as fast as you can without breaking into a jog; the equation was built on walking, and running invalidates it. Keep the pace steady rather than sprinting the last lap.
Note the time to the nearest second and, the moment you finish, your heart rate. A chest strap or a watch with a heart rate sensor is easiest; otherwise count your pulse at the wrist for 15 seconds and multiply by four, immediately, because heart rate falls fast once you stop. Enter the time as decimal minutes: 14 minutes and 30 seconds is 14.5.
The test works best when the finishing heart rate is at least 120 beats per minute. If you finished well below that, you walked too gently for the regression to see your fitness and the estimate will read high; repeat it at a harder walking pace. If you cannot walk a mile briskly because of pain, breathlessness or a heart condition, do not force it: a supervised exercise test at a clinic is the right tool.
Where your number sits: age and sex reference values
The FRIEND registry (Kaminsky and colleagues, 2015) pooled directly measured treadmill VO2 max from US adults and published percentiles by decade. The 50th percentile for men aged 20 to 29 is 48.0 mL/kg/min and for women 37.6; by ages 70 to 79 the medians fall to 24.4 for men and 18.3 for women. Between those endpoints the median drops roughly 10 percent per decade, so a man in his forties near 40 and a woman in her forties near 31 are close to the middle of the registry.
Two cautions. The registry measured people breathing into a mask on a treadmill pushed to exhaustion; a walk-test estimate carries about 5 mL/kg/min of error on top of day-to-day variation, so treat a percentile from this page as a neighborhood, not an address. And the registry describes people who were referred for or volunteered for maximal testing, which skews slightly fitter than the general population.
The ACSM Guidelines for Exercise Testing and Prescription reproduce fitness classifications by age and sex that derive from the same registry and from the Cooper Institute data. Clinicians and exercise physiologists use them in the same way: as a reference for where you are, never as a pass or fail.
The other two field methods, and why this page uses only the walk
The Cooper 12-minute run (Cooper, JAMA 1968) estimates VO2 max from the distance you can run in 12 minutes: VO2 max = (distance in meters minus 504.9) divided by 44.73. It was derived in 115 US Air Force men and correlated 0.90 with treadmill testing. It demands a maximal effort, which is why it suits trained runners and is a poor idea for someone returning to exercise or anyone with a heart condition. A 2,400 meter run gives about 42 mL/kg/min.
The heart rate ratio method (Uth and colleagues, European Journal of Applied Physiology 2004) multiplies the ratio of your maximal to resting heart rate by 15.3. With a maximal rate of 180 and a resting rate of 60 the ratio is 3.0 and the estimate 45.9 mL/kg/min. It was derived in a small group of trained men and depends entirely on knowing a true maximal heart rate; using an age formula for that number can swing the estimate by 5 to 8 points either way. It is a rough screening figure, not a test.
This page implements only the Rockport walk because it is the method validated across the widest adult age range (30 to 69) in both sexes, it is submaximal, and every input is something you can measure at home. If you have a measured VO2 max from a clinic or a laboratory, trust that over any field estimate.
Methodology and sources
The calculator implements the Rockport Fitness Walking Test regression published by Kline, Porcari, Hintermeister and colleagues in Medicine and Science in Sports and Exercise in 1987. VO2 max in mL/kg/min = 132.853 minus 0.0769 times body weight in pounds, minus 0.3877 times age in years, plus 6.315 for men (0 for women), minus 3.2649 times the walk time in minutes, minus 0.1565 times the heart rate at the end of the mile. It was derived in 343 adults (165 men, 178 women) aged 30 to 69 against treadmill-measured VO2 max, with a correlation of 0.88 and a standard error of estimate of 5.0 mL/kg/min. Outside that age range, in people who jog part of the mile, and in anyone whose finishing heart rate stays under about 120 beats per minute, the error grows and the estimate tends to read high.
How this is calculated: a 70 kg (154.3 lb) man aged 30 who walks the mile in 14.0 minutes and finishes at 130 beats per minute scores 132.853 minus 0.0769 x 154.3 (11.9) minus 0.3877 x 30 (11.6) plus 6.315 minus 3.2649 x 14 (45.7) minus 0.1565 x 130 (20.3), which is 49.6 mL/kg/min. Weight entered in kilograms is converted to pounds with the factor 2.2046 before the arithmetic. Dividing the result by 3.5 gives the equivalent in METs, the unit most mortality studies use.
The result bands are educational groupings set against the FRIEND registry reference standards (Kaminsky, Arena and Myers, Mayo Clinic Proceedings 2015) and the fitness and mortality literature (Kodama and colleagues, JAMA 2009; Mandsager and colleagues, JAMA Network Open 2018). Because VO2 max falls with age and runs lower in women, the bands name the groups for which each range is typical rather than labeling anyone fit or unfit. Reference values differ between registries and testing protocols, and a single field test is less reliable than two taken a week apart.
Medical review: Medical review pending. Last updated .
References
- Kline GM, Porcari JP, Hintermeister R, et al. Estimation of VO2max from a one-mile track walk, gender, age, and body weight. Med Sci Sports Exerc. 1987;19(3):253-259.
- Kaminsky LA, Arena R, Myers J. Reference standards for cardiorespiratory fitness measured with cardiopulmonary exercise testing: data from the Fitness Registry and the Importance of Exercise National Database. Mayo Clin Proc. 2015;90(11):1515-1523. doi:10.1016/j.mayocp.2015.07.026
- Cooper KH. A means of assessing maximal oxygen intake: correlation between field and treadmill testing. JAMA. 1968;203(3):201-204.
- Uth N, Sorensen H, Overgaard K, Pedersen PK. Estimation of VO2max from the ratio between HRmax and HRrest: the Heart Rate Ratio Method. Eur J Appl Physiol. 2004;91(1):111-115.
- Kodama S, Saito K, Tanaka S, et al. Cardiorespiratory fitness as a quantitative predictor of all-cause mortality and cardiovascular events in healthy men and women: a meta-analysis. JAMA. 2009;301(19):2024-2035.