VO2 max: Definition

Maximal oxygen intake (VO2max)

VO2 max is the maximum amount of oxygen an individual can consume per minute. It can be measured by a VO2max (maximal oxygen intake) test.

The test, which is usually carried out by a fitness expert at a sports centre, takes around 10 minutes. Depending on how fit the individual is, the test involves walking or running on a treadmill or pedalling on a stationary bicycle. The treadmill or bicycle is programmed to increase in gradient or speed every minute or two until maximum intensity is reached. This is the point at which oxygen intake levels off or when the individual is no longer able to keep up with the machine. The individual’s heart rate is measured using electrodes, and a mask worn over the mouth directs the exhaled air into an analyser.

Scores are litres of oxygen per minute divided by body weight in kilos. Expressed in millilitres of oxygen per kilogram of body weight, the average score for a young man is 45-48 and 39-41 for a young woman. Active men may score in the 50s and 60s and active women may score in the 40s and 50s. Male endurance athletes have been measured in the 80s and females in the 70s.

VO2max decreases by about 10 per cent with each decade, but regular aerobic activity cuts this decline to just 2-3 per cent. The VO2max test requires a fitness instructor to set up the machinery and to calculate the test result.