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VO2 max

VO₂ max is the maximum oxygen your body can use during exercise, in ml/kg/min. The strongest single fitness correlate of all-cause mortality — going from 'poor' to 'average' is the biggest single health investment most adults can make.

Updated May 2026 · 4 min read
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Definition

VO₂ max is the maximum oxygen your body can use during exercise, in ml/kg/min. The strongest single fitness correlate of all-cause mortality — going from 'poor' to 'average' is the biggest single health investment most adults can make.

What it means

Measured directly via a metabolic cart in a lab; estimated via the Cooper 12-minute run, Rockport 1-mile walk test, or resting heart rate proxies. Typical adult ranges: 35-45 (average), 45-55 (good), 55+ (excellent). Genetics + age set the ceiling; training moves you 15-25% within that ceiling. Decline after 30 is roughly 1% per year without training.

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Why it matters

Mandsager et al. (2018, JAMA): VO₂ max correlated with all-cause mortality more strongly than smoking, diabetes, or hypertension. The fitness investment with highest payoff. Build it via Zone 2 cardio (4-5 hrs/wk) + 1-2 high-intensity intervals/wk.

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Frequently asked questions

How fast can I improve it?

10-20% improvement in 8-12 weeks of structured training. Plateau is typical after 6-12 months unless you keep adding stimulus.

Wearable VO₂ max vs lab?

Apple Watch / Garmin VO₂ max estimates are within 5-10% of lab measurements for most users. Useful for tracking trends, not for absolute precision.

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