What is VO₂max?
The maximum rate at which you can consume oxygen during exercise, in millilitres per kilogram per minute. It sets the ceiling on aerobic performance — but not, on its own, your race times.
VO₂max is the highest rate of oxygen uptake you can achieve, and it is limited mainly by how much oxygenated blood your heart can deliver rather than by how much your muscles can use. Expressed relative to body mass, it lets you compare runners of different sizes, which is why it is quoted in mL/kg/min rather than litres per minute.
It is a ceiling, not a performance. Race times depend on three things together: VO₂max, the fraction of it you can sustain (your threshold), and how much oxygen it costs you to run at a given speed (your running economy). The Joyner model weights these at roughly 45%, 30% and 25% respectively — which means a runner can improve substantially with VO₂max unchanged.
It also responds differently depending on where you start. Untrained people can raise VO₂max dramatically in a few months. Already-trained distance runners often see very little movement, which is not a training failure — it is the ceiling being close to its structural limit, with the remaining gains available in threshold and economy instead.
Age matters too. Peak values sit near the mid-twenties and decline by roughly 0.5–0.7% per year in people who stay active, considerably faster in those who do not.
Key numbers
| Ceiling at age 25 | ~85 (M) / ~72 (F) | mL/kg/min, elite upper bound |
|---|---|---|
| Age decline | 0.5–0.7% per year | active adults, above ~35 |
| Weight in race prediction | ~45% | Joyner model |
Work it out for yourself
Race time predictor — Combine VO₂max, threshold and economy into a race-time forecast.
Frequently asked questions
What is a good VO₂max for a runner?
It depends heavily on age and sex, and the useful range is wide. Recreational runners commonly sit in the 40s and 50s, well-trained club runners in the 55–70 band, and elite distance runners above that, with the highest recorded values approaching 85 for men and 72 for women at peak age. A number in the 40s supports a perfectly respectable marathon.
Can you increase VO₂max?
Yes, though how much depends on your starting point. Untrained individuals often gain 15–20% within a few months. Trained distance runners typically see far smaller changes, and their improvements come mostly from threshold and running economy instead.
Sources
- Joyner & Coyle (2008). Endurance exercise performance: the physiology of champions. Journal of Physiology.
- Tanaka & Seals (2008). Endurance exercise performance in Masters athletes. Journal of Physiology.
Related explainers
Glossary: VO₂max, Joyner Model