ventilatory equivalent for oxygen

The ratio of the volume of air ventilating the lungs to the volume of oxygen consumed. It represents the amount of ventilation required for the consumption of each litre of oxygen and reflects ventilatory efficiency. It is measured as the ratio of the volume of gas expired per minute to the volume of oxygen consumed per minute (i.e. VE/VO₂). At rest the ventilatory equivalent for oxygen ranges from about 23 to 28 l air l⁻¹ oxygen consumed. It usually remains relatively constant during sub-maximal exercises, but the value may increase above 30 l air l⁻¹ oxygen consumed during maximal exercise.