Oxygen Metabolic Rates in Healthy Adults

Resting Oxygen Consumption Values

The American Heart Association defines standard resting oxygen uptake as 3.5 mL O₂ per kilogram of body weight per minute, which serves as the baseline (1 MET) for expressing exercise intensity 1, 2
This value represents sitting/resting oxygen requirements in the general adult population and is used universally to calculate metabolic equivalents during physical activity 2

Maximal oxygen consumption for men aged 20-29 is 43 ± 7.2 mL O₂/kg/min (approximately 12 METs), and for women aged 20-29 is 36 ± 6.9 mL O₂/kg/min (approximately 10 METs) 1, 2
Maximal oxygen consumption for men aged 60-69 is 33 ± 7.3 mL O₂/kg/min (approximately 9 METs), and for women aged 60-69 is 27 ± 4.7 mL O₂/kg/min (approximately 8 METs) 1, 2
The American College of Cardiology considers maximal oxygen consumption as the best measure of cardiovascular fitness, representing the greatest amount of oxygen a person can consume during dynamic exercise involving large muscle groups 1, 2