More than weight or heart rate: the fitness metric linked to longevity

VO₂ max, or maximal oxygen consumption, is a lesser-known fitness metric that can reveal a great deal about an individual's overall fitness and longevity. Unlike weight or heart rate, VO₂ max is not merely a measure of the heart or lungs, but rather a reflection of the combined performance of the entire cardiorespiratory system. In short, it represents the greatest amount of oxygen our body can take in, transport and use during maximal physical exertion.

VO₂ max is considered one of the strongest predictors of health and longevity, as it summarizes how well the respiratory, cardiovascular, and muscular systems work together under maximum capacity. This integrated performance cannot be achieved by any single gear alone; all three must cooperate to achieve optimal results. Consequently, VO₂ max has gained significant attention in recent years as a central measure for understanding physical fitness and its impact on health outcomes.

There are two primary methods to measure VO₂ max: laboratory testing and field tests. Laboratory measurement involves a maximal exercise test on a treadmill or bicycle, connected to a metabolic system that precisely measures oxygen consumption throughout the effort. Alternatively, field tests, such as the Cooper test—a 12-minute run covering the maximum distance possible—are used to estimate VO₂ max based on performance.

While smartwatches can provide an estimate of VO₂ max, they should be treated with caution, as their values may not accurately reflect reality. Regardless of the method used, the good news is that VO₂ max can be improved at any age. Regular exercise, particularly aerobic activities, is proven to increase VO₂ max, thus enhancing cardiovascular and respiratory health.