What does a VO2 max of 51 ml/kg/min mean physiologically?

A VO2 max of 51 means your body can use 51 ml of oxygen per kilogram of body weight per minute at maximum effort. For a 175-lb (79 kg) adult that's 4.0 liters of oxygen per minute — enough to sustain roughly 15 METs of activity.

How can I improve from a VO2 max of 51?

Consistent aerobic training — zone 2 workouts 2–3 times per week plus one HIIT session — typically produces 5–15% gains in 8–12 weeks. See /improve/ for specific programs.

Is 51 a Good VO2 Max?

A VO2 max of 51 ml/kg/min is "Good" for a 35-year-old man (79th percentile) and "Superior" for a 35-year-old woman (98th percentile). The table below shows how 51 ranks in every age bracket.

Want your exact percentile? Enter your age and sex in the percentile calculator.

Where 51 ml/kg/min ranks by age and sex
Age bracket	Men		Women
Age bracket	Percentile	Category	Percentile	Category
20–29	60	Good	89	Excellent
30–39	79	Good	98	Superior
40–49	88	Excellent	99	Superior
50–59	95	Superior	99	Superior
60–69	99	Superior	99	Superior
70–79	99	Superior	99	Superior

What 51 ml/kg/min means physiologically

VO2 max of 51 ml/kg/min is equivalent to 14.6 METs (one MET = 3.5 ml/kg/min, resting oxygen consumption). Practically, someone at this level can sustain steady-state exercise at roughly 60–70% of 51 — that is, 33.1 ml/kg/min, or about 9 METs — for an hour or more. For context, brisk walking is ~4 METs, jogging ~7 METs, and competitive running ~12–16 METs.

Each MET above the population median is associated with an ~10–15% reduction in all-cause mortality risk in long-term cohort studies, even after adjusting for traditional cardiovascular risk factors.

Next steps

Whether 51 is good for you depends on where you want to go. Three common paths:

If you're below average for your bracket: start with zone-2 training — the highest-return intervention for beginners.
If you're average-to-good: add Norwegian 4x4 intervals once a week. Consistent use produces 5–10% gains in 8 weeks.
If you're excellent-or-better: polarized training (80% easy / 20% hard) is the dominant approach in elite endurance programs.

Nearby values

Frequently asked questions

Is 51 a good VO2 max?: It depends on age and sex. For a 35-year-old man, 51 ml/kg/min is "Good" (79th percentile). For a 35-year-old woman, 51 is "Superior" (98th percentile). See the full table below for every age bracket.
What does a VO2 max of 51 ml/kg/min mean physiologically?: A VO2 max of 51 means your body can use 51 ml of oxygen per kilogram of body weight per minute at maximum effort. For a 175-lb (79 kg) adult that's 4.0 liters of oxygen per minute — enough to sustain roughly 15 METs of activity.
How can I improve from a VO2 max of 51?: Consistent aerobic training — zone 2 workouts 2–3 times per week plus one HIIT session — typically produces 5–15% gains in 8–12 weeks. See /improve/ for specific programs.