Your body needs oxygen all day long, but it needs more when you are exercising. VO2 max measures maximum aerobic capacity by assigning a number to the maximum amount of oxygen your body can turn into energy. The “V” denotes volume, “O2” is the chemical formula for oxygen, and “max” is short for “maximum.”

1. Is VO2 Max a New Measurement?

Not at all. A.V. Hill, a Nobel Laureate and physiologist, first proposed the measure in 1923, and though it was standardized decades later, it has not changed much from the calculation introduced nearly a century ago. While it’s been studied, argued, athletes have rarely wavered in their approach to maxing out the number and continue to attempt to boost their numbers and use it as a training tool.

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