Is Ventilatory Anaerobic Threshold a Good Index of Endurance Capacity?

Abstract

This study was undertaken to assess whether ventilatory anaerobic threshold (T vent) reflected endurance capacity (EC) in sports medical control. Fifteen subjects performed two cycle ergometer tests. The first was a maximal exercise test, which consisted of increasing the load 20 W/min until exhaustion. During this test, the gas exchange anaerobic threshold was determined and V̇O₂ max was measured. The second was an endurance exercise test, which consisted of asking the subject to work, as long as possible, a load representing 80% of his maximal aerobic power. During this test, we measured endurance time (ET). The statistical analysis showed (1) the lack of relationship between V̇O₂ max and ET and (2) the linear correlations between V̇O₂ T vent ml/min/kg and ET min (r = 0.521, P < 0.05), V̇O₂ T vent l/min and ET min (r = 0.524, P < 0.05), and T vent % V̇O₂ max and ET (r = 0.738, P < 0.01).

These results establish that ventilatory anaerobic threshold actually reflects endurance capacity. This relation can be explained referring to the muscle energetic metabolism during exercise. Therefore, T vent should be determined systematically in addition to V̇O₂ max during maximal exercise tests to better evaluate physical fitness.

Key words

anaerobic threshold - maximal oxygen uptake - endurance time - endurance capacity - physical fitness