At least, that’s the theory we’ve been working with since 1923. But a controversial new study from researchers on three continents suggests that the famous “VO2max” – the maximum amount of oxygen that you’re able to deliver to your muscles during hard exercise – isn’t really a maximum at all. Your heart and lungs don’t call the shots after all; your brain does.
The concept of VO2max was first introduced by Nobel Prize-winning physiologist A.V. Hill, who found that the amount of oxygen consumed by his muscles increased as he ran at a steadily increasing pace – up to a point. Eventually, his oxygen consumption would plateau, even if he continued to run faster and faster until he reached exhaustion. That plateau, he argued, represented his body’s “maximal oxygen uptake,” or VO2max.