What Is VO2 Max?
VO2 max is the maximum rate at which your body can take in, transport, and use oxygen during intense exercise. It's measured in millilitres of oxygen used per kilogram of body weight per minute, and it reflects how efficiently your heart, lungs, blood, and muscles work together to fuel sustained effort. A higher VO2 max means your body can produce more energy aerobically before it has to rely on the less efficient, faster-fatiguing anaerobic system.
VO2 max is influenced by genetics, but it's also trainable. Structured aerobic work, particularly a mix of steady-state training and higher-intensity intervals, improves the cardiovascular and muscular adaptations that raise it: a stronger heart pumping more blood per beat, more capillaries delivering oxygen to working muscle, and more efficient oxygen use at the cellular level.
A well-built approach doesn't chase VO2 max as an isolated number. It builds the aerobic base that supports it through appropriate training volume and intensity, layered into the same structured blocks used for strength and conditioning work.
Why Is It Important?
VO2 max is one of the strongest predictors of aerobic endurance performance, and it has a real effect on sports that aren't purely "endurance" sports too. Golf and tennis both involve hours on court or course with periods of elevated effort in between; a higher aerobic capacity means less fatigue accumulating over a long round or match, and faster recovery between points or holes. Running performance is directly tied to it, since VO2 max sets the ceiling for how much aerobic energy is available at any given pace. Swimming, with its continuous, whole-body demand on the cardiovascular system, relies heavily on it too.
Beyond sport-specific performance, VO2 max is also one of the most consistently cited markers of long-term health. Research has repeatedly linked higher aerobic fitness to lower risk of cardiovascular disease and greater longevity, independent of other factors. That makes it relevant even to athletes whose sport doesn't obviously demand endurance, since the training that improves it carries benefits well beyond the field, court, or pool.
Who Is It For?
VO2 max training isn't just for distance runners and endurance athletes, though it's central to their performance. It applies to anyone whose sport involves sustained effort, or who wants the long-term health benefits that come with a stronger aerobic base.
For runners and swimmers, improving VO2 max directly raises the ceiling on sustainable pace and race performance. For golfers and tennis players, it supports the ability to stay sharp and recover between efforts across a long round or match, rather than fading in the closing holes or final set. For HYROX and hybrid athletes, aerobic capacity is one of the two core pillars the entire format is built around, alongside strength. For anyone training primarily for general health rather than a specific sport, VO2 max is one of the most evidence-backed markers to build and track over time.
In short, VO2 max training is for anyone who wants their body to sustain effort for longer, recover faster between efforts, and build a foundation of fitness that supports both performance and long-term health.