A VO2 Max Test is a measurement that reflects a person’s ability to perform sustained exercise. It is generally considered the best indicator of cardiovascular fitness and aerobic endurance. The actual measurement is “milliliters of oxygen used in one minute per kilogram of body weight.” It is suitable for a wide range of individuals, from the sedentary to elite athletes.
VO2 Max is the maximum rate of oxygen consumption that can be attained during the most intense exercise possible. The measurement requires that the subject breathe into an oxygen consumption analyzer during an all-out effort (usually on a treadmill or bicycle) as part of a graded exercise protocol. These protocols involve specific increases in the speed and intensity of the exercise. While exercising, the person wears a mask to collect all the air he breathes in and out for a measurement of the volume of exhaled gas and the concentration of oxygen in that exhaled gas. This determines how much oxygen is used during each minute of the exercise test.
A person’s oxygen consumption rises in a linear relationship with exercise intensity — up to a point. There are specific physiological markers (AeT, AT) that can be detected throughout the test as oxygen consumption is measured. Eventually, oxygen consumption plateaus even if the exercise intensity increases. When the person is no longer able to keep up with the oxygen demands of his muscles and complete fatigue forces him to stop exercising, then his oxygen consumption has reached a maximum, and VO2 Max can be calculated. The test usually takes between 10 and 15 minutes