How to use the VO2 Max
- Choose an estimation method — race time, Cooper test, or resting heart rate.
- Enter the required inputs for that method.
- Read the estimate in ml/kg/min and its fitness category.
- Retest the same way in eight to twelve weeks to measure change.
How the calculation works
Race-based estimation uses Daniels and Gilbert's velocity-to-oxygen-cost relationship, which is the most accurate non-laboratory approach because a genuine race effort reveals sustainable oxygen uptake directly. The Cooper 12-minute test uses VO2max = (distance in metres − 504.9) ÷ 44.73, and the heart-rate method, 15.3 × HRmax ÷ HRrest, is convenient but crude, inheriting all the error in an estimated maximum.
Values are expressed relative to body mass, so losing fat raises VO2 max without any change in oxygen delivery. Typical untrained men score 35 to 45 and women 27 to 38, trained endurance athletes reach 60 to 75, and elite figures exceed 80. Trainability is limited — most people improve 15 to 20% from a sedentary baseline, and beyond that gains in running economy and lactate threshold matter more for actual race performance.
Cooper: VO2max = (metres − 504.9) / 44.73 ; HR method: 15.3 × HRmax / HRrest ; race method per Daniels' oxygen cost tablesSource: Cooper 12-minute test; Daniels and Gilbert VDOT tables; Uth et al. heart-rate ratio method.
Worked example
A runner covers 2,780 m in the Cooper test, with HRmax 186 and resting 54.
- Cooper: (2,780 − 504.9) / 44.73 = 50.9 ml/kg/min.
- HR ratio: 15.3 × 186 / 54 = 52.7.
- The two agree closely, which raises confidence.
- That places a 40-year-old man in the excellent category.
Roughly 51 to 53 ml/kg/min — an excellent value for a recreational runner, and a solid baseline to retest against in three months.
Frequently asked questions
What is a good VO2 max?+
Untrained men typically score 35 to 45 and women 27 to 38. Trained endurance athletes reach 60 to 75, and elite competitors exceed 80. Values decline with age.
How much can I improve it?+
Most people gain 15 to 20% from a sedentary starting point over several months. Beyond that, further performance comes from running economy and lactate threshold rather than raw capacity.
Which estimation method is best?+
A recent all-out race time, because it reflects genuine sustainable effort. The heart-rate ratio is the least reliable, since it depends on an estimated maximum.
Are watch estimates accurate?+
They track direction well but can be off by several points in absolute terms. Use the same device and method consistently and pay attention to the trend, not the number.
Last reviewed August 31, 2026. We review this page whenever the underlying formula, tax year, published rate or standard changes.