VO2max and longevity: why this number predicts more than speed

VO2max falls roughly 10% per decade without training and is among the strongest predictors of long-term mortality in the published research. What the number means, and what actually raises it.

VO2max measures the peak rate at which your body can use oxygen during exercise. It's the single number that best captures your cardiorespiratory fitness — and one of the most consistently reproduced predictors of long-term mortality risk in the exercise science literature.

“Low cardiorespiratory fitness carries a mortality risk comparable to established conditions such as coronary artery disease and smoking.”

The decline is real, and it's not linear with effort

Without targeted training, VO2max declines roughly 10% per decade past early adulthood. The encouraging part: it responds to training at any age, and the sessions that move it most are unglamorous — Zone 2 volume plus a smaller amount of structured high-intensity work.

The capability threshold

Roughly 18 ml/kg/min of VO2max is the rough threshold most people need to keep climbing stairs and carrying groceries without strain, independent of age. The useful exercise isn't comparing your number to a chart — it's projecting your own trend line forward and asking whether it's heading toward or away from that floor while there's still time to change the slope.