What is VO₂max?
VO₂max (maximal oxygen uptake) is the maximum rate at which your body can consume oxygen during sustained exercise. It's measured in millilitres of oxygen per kilogram of body weight per minute (mL/kg/min) and is widely regarded as the best single predictor of aerobic endurance performance.
The Jack Daniels Method
Running coach Jack Daniels developed a system to translate race performances into a VO₂max estimate (VDOT). The calculation uses your running speed and race duration to estimate what percentage of VO₂max you sustained during the race, then back-calculates your maximum:
VO₂demand = −4.60 + 0.182258v + 0.000104v²
%VO₂max = 0.8 + 0.189e^(−0.01277t) + 0.299e^(−0.1933t)
VO₂max = VO₂demand / %VO₂max
Where v is speed in m/min and t is race duration in minutes.
How to Improve VO₂max
VO₂max responds best to high-intensity interval training at or near VO₂max pace (interval zone), interspersed with adequate easy running. Most recreational runners can improve VO₂max by 10–20% with consistent training over 6–12 months. Elite athletes have genetically high ceilings but still improve through volume and intensity.