VO2 max
The maximum volume of oxygen the body can use during exercise, expressed in millilitres of oxygen per kilogram of body weight per minute (ml/kg/min).
VO2 max is a measure of cardiovascular capacity and aerobic metabolism. It shows how much oxygen the heart can pump, the lungs can take in and the muscles can use.
An elite endurance athlete can have a VO2 max of 70+ ml/kg/min; a sedentary person around 35 ml/kg/min.
Factors that improve it:
- High-intensity interval training (HIIT)
- Continuous moderate-intensity training
- A diet rich in iron and antioxidants to support mitochondrial energy
A fresh angle (nutrition): VO2 max also depends on mitochondrial health and the antioxidant system. A diet rich in vitamins C and E and in polyphenols (tea, berries, dark chocolate) supports aerobic capacity.
Also: VO2 max declines quickly if you stop training (2-3 weeks without exercise leads to a noticeable loss). It is a very activity-specific adaptation.
One last point: VO2 max is not the only indicator of performance. Energy efficiency and lactate threshold matter too. Two runners with the same VO2 max will not perform the same if they differ in running economy.