VO2 max calculator and fitness age

Estimate your VO2 max without a treadmill test. The calculator uses the formula researchers at NTNU in Norway built from 4,637 healthy adults in the HUNT study, and shows your fitness age.

What is VO2 max?

VO2 max is the most oxygen your body can take up and use during hard exercise, measured in millilitres per kilogram of body weight per minute (ml/kg/min). It shows how well your heart, lungs and muscles work together. The exact number comes from a max test on a treadmill or bike with a breathing mask.

It is also one of the strongest markers of long-term health. When NTNU estimated the fitness of 37,112 healthy adults in the first HUNT study, every 1 MET higher fitness (about 3.5 ml/kg/min) went with a 21% lower risk of dying from cardiovascular disease among those under 60 (Nes et al., 2014).

How the calculator works

Researchers at the Norwegian University of Science and Technology (NTNU) measured VO2 max directly in 4,637 healthy adults and built a formula that predicts it from five things: sex, age, waist, resting heart rate and how much you exercise (Nes et al., 2011). Exercise is scored from how often, how hard and how long you train.

Your fitness age is the age at which the average healthy man or woman in HUNT3 has the same VO2 max as you. The averages come from max tests on 3,816 healthy people aged 20–90 (Loe et al., 2013). The formula is accurate on average, but the standard error is 5.7 ml/kg/min for men and 5.1 for women, so treat your result as an estimate.

Average VO2 max by age

Mean ± standard deviation in ml/kg/min for healthy adults in the HUNT3 fitness study:

Age	Women	Men
20–29	43.0 ± 7.7	54.4 ± 8.4
30–39	40.0 ± 6.8	49.1 ± 7.5
40–49	38.4 ± 6.9	47.2 ± 7.7
50–59	34.4 ± 5.7	42.6 ± 7.4
60–69	31.1 ± 5.1	39.2 ± 6.7
70+	28.3 ± 5.2	35.3 ± 6.5

How to improve your VO2 max

High-intensity intervals raise VO2 max more than easy training. In a study from NTNU, 40 moderately trained men trained three times a week for eight weeks. The 4x4 group (four 4-minute intervals at 90–95% of max heart rate, with 3 minutes of easy activity between) improved VO2 max by 7.2%, from 55.5 to 60.4 ml/kg/min. Long, easy runs with the same total work did not give the same gain (Helgerud et al., 2007).

One or two interval sessions a week is a good start. Find your max heart rate and the 4x4 targets with the heart rate zone calculator. A smaller waist and a lower resting heart rate also lower your fitness age in the formula.

Frequently asked questions

What is a good VO2 max?

It depends on your age and sex. In the Norwegian HUNT study, healthy men in their 40s averaged 47.2 ml/kg/min and women 38.4. Above the average for your age is good, and the higher the better for health. The table on this page shows the averages for every age group.

How accurate is a VO2 max calculator?

The HUNT formula is accurate on average, with a standard error of 5.7 ml/kg/min for men and 5.1 for women. For one person it can miss by enough to shift the fitness age by 10–15 years. A max test on a treadmill or bike with a breathing mask gives a more precise number.

What is fitness age?

Fitness age is the age at which the average healthy man or woman has the same VO2 max as you. If your VO2 max matches the average 35-year-old, your fitness age is 35, whatever your actual age.

How can I increase my VO2 max?

High-intensity intervals work best. In a Norwegian study, the 4x4 workout (four 4-minute intervals at 90–95% of max heart rate with 3 minutes of easy activity between) raised VO2 max by 7.2% in eight weeks, while easy long runs with the same total work did not.

Sources

• Nes et al. (2011): Estimating V̇O₂peak from a nonexercise prediction model: the HUNT Study, Norway, Med Sci Sports Exerc
• Loe et al. (2013): Aerobic capacity reference data in 3816 healthy men and women 20–90 years, PLoS One
• Nes et al. (2014): A simple nonexercise model of cardiorespiratory fitness predicts long-term mortality, Med Sci Sports Exerc
• Helgerud et al. (2007): Aerobic high-intensity intervals improve VO₂max more than moderate training, Med Sci Sports Exerc

The calculator gives an estimate based on formulas and averages from large studies. It does not replace an assessment by a doctor. The numbers you enter stay in your browser and are not stored.