Effet de 4 semaines d'entraînement sur le temps limite à V̇O₂max

The purpose of this study was to examine the effect of 4 weeks training in running on the time spent at V̇O₂max (tlim V̇O ₂max). Eight athletes carried out, before and after an aerobic training, an incremental and five exhaustive tests at 90, 95, 100, 115% vV̇O₂max and at the critical power at V̇O₂max (CV'; slope of the linear relation between the tlim V̇O₂max and the distance limit at V̇O₂max). This training did not significantly improve V̇O₂max (p = 0.17) or tlim V̇O ₂max (p = 0.72). However, the "tlim V̇O₂max- intensity" curve was shifted toward the right, meaning that the athlete had to run at a higher intensity after training to obtain the same tlim V̇O₂max. Tlim V̇O₂max at CV' before training was significantly higher than tlim V̇O₂max at 90, 95, 100, and 115% vV̇O₂max (p < 0.05). This training increased CV' in absolute value (13.9 ± 1.3 vs. 14.9 ± 1.2 km·h^-1, p < 0.05; n = 6) but not in relative value (86 ± 4 vs. 86 ± 5% vV̇O₂max; p = 0.9). In conclusion, in spite of the shift of the "tlim V̇O₂max-intensity" curve, tlim V̇O ₂max was not significantly increased by this training. Furthermore, CV' allowed subjects to spend the longest time of exercise at V̇O ₂max during a continuous exercise with constant speed, but CV', expressed in % vV̇O₂max, did not improve with this training.