Guide · Performance
VO2 max: what it is, chart by age and how to improve it
Why VO2 max is one of the best predictors of longevity, and how to train for it.
VO2 max is the maximum amount of oxygen your body can use per minute during maximal effort. In the United States, the median measured in lab tests falls from 48 mL/kg/min in men aged 20 to 29 to 24 at age 70. In 122,000 people, the fitter the group, the longer they lived: the elite group lived the longest.
In this article
- What VO2 max is
- VO2 max and longevity
- VO2 max chart by age
- What a good VO2 max is
- How VO2 max is measured (and whether your watch measures it)
- How to improve VO2 max
- How to track VO2 max over time
- Frequently asked questions
- Sources
What VO2 max is
VO2 max is the largest amount of oxygen your body can take in, transport and use per minute during maximal effort. It depends on the lungs, heart, blood and muscles working together. That is why it is the most widely used measure of cardiorespiratory fitness, or aerobic fitness.
It is usually expressed in millilitres of oxygen per kilogram of body weight per minute (mL/kg/min), so people of different sizes can be compared. In some clinical studies the same capacity appears in METs, a unit of energy expenditure; 1 extra MET is roughly the same as running about 1 km/h faster EV A.
The American Heart Association (AHA) published a scientific statement arguing that cardiorespiratory fitness should be treated as a vital sign in clinical practice, alongside blood pressure and heart rate EV A.
VO2 max and longevity
Few markers are as closely related to longevity. The main studies:
- A meta-analysis of 33 studies with more than 100,000 healthy participants found that each extra MET of aerobic capacity was associated with 13% lower risk of dying early from all causes and 15% fewer cardiovascular events EV A.
- A Cleveland Clinic study of 122,007 people who took a treadmill test found a risk of early death about five times higher in the least fit group compared with the elite group. The effect was comparable to, or greater than, that of smoking, diabetes or coronary disease EV B.
- In the same study there was no ceiling: the higher the fitness, the lower the risk, including in people over 70 EV B.
These are observational studies, which show association. Even so, the consistency of the data led the AHA to state that aerobic fitness may predict longevity better than traditional risk factors EV A. VO2 max is also one of the pieces that help explain biological age.
VO2 max chart by age
The most widely used reference in the United States comes from the FRIEND registry, which gathered treadmill cardiopulmonary tests from adults without cardiovascular disease. The table shows the median (50th percentile) for each age group: half of people are above and half below EV B.
| Age | Men | Women |
|---|---|---|
| 20 to 29 | 48.0 | 37.6 |
| 30 to 39 | 42.4 | 30.2 |
| 40 to 49 | 37.8 | 26.7 |
| 50 to 59 | 32.6 | 23.4 |
| 60 to 69 | 28.2 | 20.0 |
| 70 to 79 | 24.4 | 18.3 |
Values in mL/kg/min, measured in a treadmill cardiopulmonary test. In this group, VO2 max fell about 10% per decade EV B. A 2022 update with more than 22,000 tests found treadmill values 1.5 to 4.6 mL/kg/min lower than in 2015 EV B.
In studies that followed the same people over the years, the decline sped up with age: from 3% to 6% per decade in the 20s and 30s to more than 20% per decade from age 70 EV B. That makes training even more valuable over time.
What a good VO2 max is
There is no magic number. In the 2009 meta-analysis, people with a capacity below 7.9 METs had much higher rates of death and cardiovascular events than those with intermediate or high capacity EV A. In the study of 122,000 people, moving from the below-average group to the above-average group was already associated with lower risk EV B.
A practical goal: be above the median for your age and sex, and move up a band over time. The biggest health gain comes from leaving the least fit group.
How VO2 max is measured (and whether your watch measures it)
There are three ways, with different levels of precision:
- Cardiopulmonary exercise test. It measures the oxygen and carbon dioxide in your breath during progressive effort on a treadmill or bike. It is the reference standard and is done with professional supervision.
- Field and exercise tests without gas analysis. They estimate VO2 from speed, load or time. Useful, but they are estimates.
- Watches and wearables. They use heart rate, pace and personal data in algorithms.
Does a watch really measure VO2 max? It estimates it. A meta-analysis of 14 validation studies showed that wearables using exercise data (such as GPS runs) are almost unbiased on average for a group, but the error for one individual can exceed 9 mL/kg/min either way. Those that estimate from resting data tend to overestimate EV A.
In practice, the watch number is useful for following your trend over months. For a clinical decision or high-performance training, the cardiopulmonary test remains the reference.
How to improve VO2 max
The good news: VO2 max responds to training at any age. A meta-analysis of 28 controlled studies in adults aged 18 to 45 showed EV A:
- Continuous endurance training (running, cycling, swimming at a steady pace) raised VO2 max by about 4.9 mL/kg/min compared with no training.
- High-intensity interval training (HIIT), with hard efforts and rests, raised it by about 5.5 mL/kg/min, a small advantage over continuous training.
- Gains were larger in longer programs and in people who started less fit.
The response to training varies between people. In the HERITAGE study, 481 sedentary adults did the same program for 20 weeks: some barely improved, others gained more than 1 litre per minute. The estimated heritability of this response was up to 47% EV B.
If you have a health condition or are just starting, talk to a doctor before taking on intense training.
How to track VO2 max over time
VO2 max moves together with resting heart rate: as fitness rises, resting heart rate tends to fall. Following both over months shows whether your training is working. Look at the trend, not single days, and use the same device and the same type of workout for the estimate.
Frequently asked questions
What is a good VO2 max?
There is no single number. A practical goal is to be above the median for your age and sex: in the American FRIEND registry data, it ranges from 48 mL/kg/min in men and 37.6 in women aged 20 to 29 to 24.4 and 18.3 at ages 70 to 79. The biggest health gain comes from leaving the least fit group.
Does my watch really measure VO2 max?
It estimates it. Watches that use exercise data are accurate on average for a group, but the error for one person can exceed 9 mL/kg/min. The number is useful for following a trend over months. The reference remains the cardiopulmonary test.
How do I increase VO2 max?
With regular aerobic training. Controlled studies show average gains of about 5 mL/kg/min with both continuous and high-intensity interval training, with a small advantage for intervals. Longer programs and people who start less fit tend to gain more.
Is VO2 max linked to longevity?
Yes. In a meta-analysis of more than 100,000 people, each extra MET of aerobic capacity was associated with 13% lower risk of dying early. The American Heart Association recommends treating cardiorespiratory fitness as a vital sign.
Sources
- Ross R et al. Importance of Assessing Cardiorespiratory Fitness in Clinical Practice: a case for fitness as a clinical vital sign. AHA Scientific Statement. Circulation, 2016. doi.org/10.1161/CIR.0000000000000461 · Evidence A
- Kodama 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. doi.org/10.1001/jama.2009.681 · Evidence A
- Mandsager K et al. Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing. JAMA Network Open, 2018. doi.org/10.1001/jamanetworkopen.2018.3605 · Evidence B
- Kaminsky LA, Arena R, Myers J. Reference Standards for Cardiorespiratory Fitness Measured With Cardiopulmonary Exercise Testing: data from FRIEND. Mayo Clinic Proceedings, 2015. doi.org/10.1016/j.mayocp.2015.07.026 · Evidence B
- Kaminsky LA et al. Updated Reference Standards for Cardiorespiratory Fitness Measured with Cardiopulmonary Exercise Testing: data from FRIEND. Mayo Clinic Proceedings, 2022. doi.org/10.1016/j.mayocp.2021.08.020 · Evidence B
- Fleg JL et al. Accelerated longitudinal decline of aerobic capacity in healthy older adults. Circulation, 2005. doi.org/10.1161/CIRCULATIONAHA.105.545459 · Evidence B
- Molina-Garcia P et al. Validity of Estimating the Maximal Oxygen Consumption by Consumer Wearables: a systematic review with meta-analysis. Sports Medicine, 2022. doi.org/10.1007/s40279-021-01639-y · Evidence A
- Milanović Z et al. Effectiveness of High-Intensity Interval Training and Continuous Endurance Training for VO2max Improvements: a systematic review and meta-analysis. Sports Medicine, 2015. doi.org/10.1007/s40279-015-0365-0 · Evidence A
- Bouchard C et al. Familial aggregation of VO2max response to exercise training: results from the HERITAGE Family Study. Journal of Applied Physiology, 1999. doi.org/10.1152/jappl.1999.87.3.1003 · Evidence B