What is VO2 Max
VO2 max is the maximum rate at which your body can consume oxygen during intense exercise, and is widely regarded as the gold standard measure of cardiovascular fitness and aerobic capacity.
VO2 max — formally, maximal oxygen uptake — is the highest rate at which your body can consume oxygen during sustained, intense aerobic exercise. It is expressed in milliliters of oxygen per kilogram of body weight per minute (mL/kg/min) and is considered the most reliable single measure of cardiorespiratory fitness.
The higher your VO2 max, the more efficiently your cardiovascular and muscular systems can use oxygen to generate energy — and the better your endurance performance tends to be.
How VO2 Max Is Measured
A clinical VO2 max test (called a maximal exercise test or graded exercise test) takes place on a treadmill or cycle ergometer. Intensity is gradually increased until exhaustion while the subject breathes through a mask that analyzes the volume and composition of exhaled air. The point at which oxygen consumption stops increasing despite rising effort is the VO2 max.
Consumer fitness watches (Garmin, Apple Watch, Polar) estimate VO2 max algorithmically using heart rate data, without requiring a lab test.
Average VO2 Max Values by Age and Sex
| Category | Women (mL/kg/min) | Men (mL/kg/min) |
|---|---|---|
| Excellent | 50+ | 60+ |
| Good | 43–50 | 52–60 |
| Average | 35–43 | 43–52 |
| Below Average | 28–35 | 34–43 |
| Poor | Under 28 | Under 34 |
Elite endurance athletes — Tour de France cyclists, marathon runners — often test at 70–90+ mL/kg/min. Norwegian cross-country skier Bjørn Dæhlie is believed to hold one of the highest recorded values at 96 mL/kg/min.
What Influences VO2 Max
- Genetics — A significant portion of VO2 max potential is inherited; some individuals simply have higher ceilings
- Training — Cardiovascular training, especially sustained aerobic exercise and HIIT, increases VO2 max
- Age — VO2 max declines approximately 1% per year after age 25, though regular exercise dramatically slows this decline
- Body composition — Because VO2 max is expressed relative to body weight, excess fat mass reduces the number
- Altitude — Living or training at altitude can stimulate adaptations that improve VO2 max
How to Improve VO2 Max
The most effective training methods for improving VO2 max are those that consistently push the cardiovascular system close to its limits:
- HIIT — Interval training at 90–100% of max heart rate is the most studied and effective method for increasing VO2 max rapidly
- Tabata — The original Tabata protocol was specifically designed around VO2 max development
- Zone 4/5 training — Sustained efforts at 85–95% max heart rate for 3–8 minutes per interval
- Long slow distance (LSD) — Lower intensity but high volume running/cycling also produces VO2 max gains over time
VO2 Max and Longevity
Research published in JAMA and other major medical journals has identified VO2 max as one of the strongest predictors of all-cause mortality — more predictive than many traditional clinical markers. Individuals in the top quartile of cardiorespiratory fitness consistently show significantly lower risks of cardiovascular disease, diabetes, and premature death.
For those interested in testing their VO2 max without a lab, Garmin's fitness tracker lineup includes built-in VO2 max estimation for runners and cyclists.