What is a good VO2 max for your age?

The short answer

• ≈10%

  How much the middle VO2 max falls with each decade of age, in 7,783 US lab tests

• −13%

  Lower risk of dying during the studies for each small step up in fitness, across 33 studies of healthy adults

• 5×

  Risk of dying for the least fit quarter of patients, compared with the fittest 2%

• −6.25

  How far Apple Watch read below a lab test, in ml/kg/min, on average, in 35 young adults

Key findingA good VO2 max is one above the middle for your age and sex. The biggest health links come from moving out of the least fit group, and fitness can be raised at any age.

What is VO2 max?

VO2 max is the most oxygen your body can use during hard exercise. It is a good measure of fitness. It shows how well your heart, lungs and muscles work together when you push hard.

It is given in millilitres of oxygen per kilogram of body weight per minute (ml/kg/min). Researchers also use METs. One MET is the oxygen you use sitting still: 3.5 ml/kg/min. So a VO2 max of 35 is 10 METs.

The best way to measure it is a lab test. You run or cycle harder and harder while a mask measures your breathing. Field tests and watches can only estimate it. Our VO2 max calculator gives three such estimates.

Your genes matter too. A 2024 review notes that nearly half of the differences in fitness between people come from genes. The rest depends mainly on how active you are.

What is a good VO2 max?

There is no single number. VO2 max falls with age, and women’s values are lower than men’s at every age. So “good” means good for people of your age and sex.

The main US reference values come from the FRIEND registry. It holds 7,783 lab treadmill tests of adults aged 20 to 79 without known heart disease, from 8 labs. The middle value for men fell from 48.0 in their 20s to 24.4 in their 70s. For women, it fell from 37.6 to 18.3. That is about 10% less with each decade.

Researchers rank fitness against people of the same age and sex. Picture 100 people like you lined up from least to most fit. Then:

• The bottom quarter counts as low fitness in research.
• Above the middle is better than average. That is a good VO2 max.
• The top quarter counts as high fitness for your age.

For example, take a 45-year-old woman with a VO2 max of 30. She is above the middle for her age (26.7) but below the top quarter (32.4). The full VO2 max by age and sex table is on our calculator page.

Treat these numbers as a rough guide. A larger 2022 update from 34 US labs found treadmill values 1.5 to 4.6 points lower than these. So if you sit a little below a line, you may be closer to average than it looks.

Why VO2 max matters: fitness and a long life

This was a cohort study: a study that followed a large group of people over time. It shows a link. It can’t prove that fitness itself caused the longer lives, because healthier people may simply be able to exercise harder.

The researchers then allowed for age, sex and other health problems. The gap between below-average and above-average fitness was about as big as the gap for smoking or for diabetes. There was no top limit either: the elite group still did better than the high group. When people were split by age, that extra edge showed only in those aged 70 or over.

Pooled studies point the same way. A 2009 meta-analysis pooled 33 studies of healthy adults. It looked at steps of 1 MET (3.5 ml/kg/min). Each step up in fitness went with a 13% lower risk of dying during the studies, and a 15% lower risk of heart disease events. People below 7.9 METs (about 28 ml/kg/min) had 1.7 times the risk of death of people at 10.9 METs (about 38) or more.

A 2024 review of reviews combined 26 meta-analyses, covering 199 studies and more than 20.9 million records. High fitness went with a 41% to 53% lower risk of early death than low fitness. Each 1 MET step went with an 11% to 17% lower risk. The review rated how sure we can be as very low to moderate, mainly because most of the people studied were men.

How accurate is Apple Watch VO2 max?

Apple Watch estimates VO2 max and calls it Cardio Fitness. It uses your heart rate during outdoor walks, runs or hikes on fairly flat ground. It also uses GPS, your age, sex, height and weight.

A 2026 study checked the Apple Watch Series 10 against a lab test. It tested 40 healthy adults in Ireland and analysed 35 of them. Most were young, with an average age of 23, and very fit.

• On average, the watch read 6.25 ml/kg/min lower than the lab test.
• For one person, it could be anywhere from 18 points too low to 6 points too high.
• It put only 5 of the 35 people (14%) in the right fitness band. Half were two or more bands out.
• The gap was bigger in women (8.6 points low) than in men (3.8 points low), but these groups were small.

An earlier study by the same team, in 30 people, found much the same. The watch read about 6 points low.

So one watch reading isn’t a lab result, and it may place you in the wrong part of an age chart. The watch may still help you follow your own trend over months. But no independent study has yet checked how well it tracks change.

How to increase VO2 max

Regular cardio raises VO2 max. A 2015 meta-analysis pooled 28 trials with 723 healthy adults aged 18 to 45. Compared with doing nothing, steady endurance training raised VO2 max by 4.9 ml/kg/min. Interval training raised it by 5.5. Intervals are short bursts of hard effort with easy breaks in between.

Those gains are about 1.4 to 1.6 METs (our calculation). In the studies above, people who were 1 MET fitter had a lower risk. That doesn’t prove that raising your own fitness lowers your risk. But it is a sensible goal.

Gains were bigger in longer programmes and in people who started less fit. The 2024 review adds that brisk walking for about 150 minutes a week can raise fitness a lot in people who are unfit. It also found the biggest health links when people moved from unfit to fit.

To plan your week, see our zone 2 training explainer and how much exercise you need each week.

Claims and evidence

• ClaimThere is one good VO2 max number for everyone.

  EvidenceIt depends on age and sex. In US lab tests, the middle value for men fell from 48.0 in their 20s to 24.4 in their 70s.

• ClaimPast a certain level, more fitness doesn’t help.

  EvidenceIn 122,007 patients, the fittest 2% still did better than the next group, and no upper limit was seen. By age, that edge showed in people aged 70 or older.

• ClaimYour Apple Watch VO2 max is as good as a lab test.

  EvidenceIn 35 young adults, it read 6.25 ml/kg/min low on average and put only 14% in the right fitness band.

• ClaimVO2 max is all down to your genes.

  EvidenceGenes explain nearly half of the differences between people. In 28 trials, training raised VO2 max by about 5 ml/kg/min.

What this means for you

What the research can’t tell you yet

• Links, not proof. The fitness studies followed people over time. Healthier people may simply be fitter, so the studies can’t prove that fitness causes a longer life.
• Who was studied. Most of the survival studies were of men, and the age charts come from US labs.
• Estimates, not measurements. The study of 122,007 patients estimated fitness from treadmill speed and slope, not from breathing.
• Watches. The Apple Watch study had 35 young, mostly fit adults, one watch model and one test each.
• Older people. Few people over 70 were tested for the age charts.

How Bodyvault uses this research

Bodyvault reads the VO2 max estimate your watch saves to Apple Health or Health Connect. The app’s Heart section shows your latest value with a six-month trend. The detail view labels it a watch estimate and suggests you compare it only with your own history. Bodyvault doesn’t turn your VO2 max into a risk of dying.

General information about fitness and nutrition, not medical advice. If you have a health condition, are pregnant or take medication, talk to your doctor before changing your diet or training.