The most accurate way to calculate your VO2 max is in a clinical setting, says Tanayan. “A CPET (cardiopulmonary exercise test) is the gold standard of estimating someone’s VO2 max,” he says. In the ...

Hardcore endurance athletes have tracked the metric for decades, but it is increasingly touted as a measure of fitness and health for the average person.

The concentration of oxygen at sea level is about 21% and the barometric pressure averages 760 mmHg. As altitude increases, the concentration remains the same but the number of oxygen molecules per ...