VO₂ Max Calculator
Estimate your VO₂ max from your resting heart rate in seconds — no lab, no mask. Then see where your breathing muscles fit into raising it.
What your VO2 max tells you
VO2 max is the ceiling of your aerobic engine: the maximum volume of oxygen your body can take in, transport, and use per minute of intense effort. It depends on your lungs, heart, blood, and muscles working as one system. The higher your VO2 max, the more work you can sustain aerobically before fatigue forces you to slow down.
The overlooked link: your breathing muscles
Most training plans target the heart and legs and ignore the muscles that move air. Yet during hard exercise your diaphragm and intercostal muscles can consume up to 15 percent of total oxygen, and when they fatigue, blood is redirected away from your limbs. Strengthening them with resistance-based inspiratory muscle training frees up oxygen for the muscles that drive performance.
Frequently asked questions
What is VO2 max?
VO2 max is the maximum amount of oxygen your body can use during intense exercise, measured in milliliters of oxygen per kilogram of body weight per minute. It is widely considered the best single measure of cardiovascular fitness and aerobic endurance.
How accurate is a VO2 max calculator?
Calculators based on resting heart rate, like the Uth heart-rate-ratio method used here, provide a solid estimate within roughly 10 percent of lab values for most people. For exact numbers, a laboratory test with gas exchange analysis is the gold standard.
What is a good VO2 max for my age?
For men in their 30s, above 42 ml/kg/min is good and above 50 is very good. For women in their 30s, above 37 is good and above 44 is very good. Elite endurance athletes commonly exceed 60 to 70 ml/kg/min.
Can breathing training improve VO2 max?
Inspiratory muscle training does not directly raise VO2 max, but research shows it improves time to exhaustion, reduces perceived exertion, and delays diaphragm fatigue, which lets you train harder and sustain output closer to your VO2 max for longer.
Train the 15% you're ignoring
Your breathing muscles can consume up to 15% of your oxygen at max effort. The O2Trainer makes them stronger, so your legs get more.
Shop the O2Trainer
