VO₂ max: How To Measure and Improve It

VO₂ max is the maximum rate of oxygen consumption measured during incremental exercise; that is, the exercise of increasing intensity. The name is derived from three abbreviations: “V̇” for volume, “O₂” for oxygen, and “max” for maximum.

VO₂ max shows how well your heart pushes blood to your muscles and how efficiently your muscles can extract that oxygen from your circulating blood. As you breathe in oxygen, it powers a metabolic reaction within your muscle cells that gives your muscles energy called adenosine triphosphate (ATP). You breathe faster and deeper while exercising because your body needs more energy to work.

By measuring how much oxygen is converted to carbon dioxide, you’ll find out how many calories you burn at different levels of exercise intensity. Your heart rate will also be monitored at different exercise intensities.

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.

The measurement requires you to breathe into an oxygen consumption analyzer during an all-out effort (treadmill or an exercise bike) as part of a graded exercise protocol. These protocols involve specific increases in the speed and intensity of the exercise. While exercising, you will wear 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.

Your 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 you are no longer able to keep up with the oxygen demands of your muscles and complete fatigue forces you to stop exercising, then your oxygen consumption has reached a maximum, and VO₂ Max can be calculated.

The test usually takes between 10 and 15 minutes.