VO2 max is a clinical measurement of a person’s fitness level; it reflects the aerobic physical fitness of the individual. This measurement is also known as maximal oxygen consumption, maximal oxygen uptake, peak oxygen uptake or maximal aerobic capacity.
VO2 max is a measure of the maximum volume of oxygen that an athlete can use. It is measured in millilitres per kilogram of body weight per minute (ml/kg/min).
VO2 max is usually measured during incremental exercise, most typically on a motorized treadmill with a breathing apparatus strapped to the person’s mouth and nose. They measure ventilation and oxygen and carbon dioxide concentration of the inhaled and exhaled air. VO2 max is reached when oxygen consumption remains at a steady state despite an increase in workload.