Ventilatory threshold measurement to evaluate maximal endurance performance

The ventilatory (anaerobic) threshold during short-term exercise has been defined as the O2 uptake (VO2) immediately below the VO2 at which pulmonary ventilation (VE) increases disproportionally relative to VO2 and the ventilatory threshold for long-term exercise as the VO2 immediately below the VO2 at which the VE continues to increase with time rather than attain a steady state. Maximal endurance performance was determined by measurement of the maximal endurance time during treadmill runs at 90%, and 70% of the previously determined VO2 max. The purpose of the present study was to investigate how maximal endurance performance was related to both ventilatory thresholds and to VO2max, and to select which variable best explained maximal endurance performance. The subjects were 11 healthy males. Maximal endurance performance was significantly correlated with the ventilatory threshold for long-term exercise and VO2max. A stepwise multiple regression analysis indicated that maximal endurance performance was best predicted by the ventilatory threshold for long-term exercise. Combination of variables could not improve the prediction. It is concluded that the ventilatory threshold for long-term exercise better explains maximal endurance performance than VO2max or the ventilatory threshold during short-term exercise.