Gender effect on the relationship of time limit at 100% VO2max with other bioenergetic characteristics

The aim of this study was to investigate the influence of gender on the possible contribution of t lim at v a max (minimal speed that elicts VO 2 max ) in performance speeds. The male and female elite middle-distance runners had similar performance (IAAF scores). Fourteen female and fifteen male (25.2 ± 3.6 and 25.1 ± 4.2 yr old ; VO 2max = 63.2 ± 4.2 and 77.7 ± 6.4 ml.kg -1 .min -1 ; v a max = 17.3 ± 0.7 and 20.8 ± 1.1 km.h -1 , respectively) performed three exercise tests on a treadmill (3° slope) within a 2-wk period : an incremental test to determine VO 2max , v a max and the velocity at the onset of blood lactate accumulation (vOBLA) ; an exhaustive constant velocity test to determine t lim at v a max ; and an exhaustive constant velocity test at 110% v a max to determine the accumulated oxygen deficit (AOD). There were no effects of gender, i.e., no significant differences were observed between female and male for t lim at v a max (421 ± 129 vs 367 ± 118 s respectively ; P = 0.24), vOBLA as %v a max (88.4 ± 2.7 vs 90.4 3% of v a max ; P = 0.07), AOD (40.1 ± 14.9 vs 48.9 ± 21.3 ml.O 2 .kg -1 ; P = 0.22), running economy at the same absolute speed, i.e., 14 km.h -1 (53.4 ± 2.6 vs 52.7 ± 4.1 ml.O 2 .min -1 .kg -1 ; P = 0.64) or for gross oxygen cost of running (CR) at the same relative velocity (75% v a max ) (0.214 ± 0.001 vs 0.214 ± 0.002 ml.O 2 .kg -1 .m -1 ; P = 0.94). However, an effect of gender was found on the relationship between the bioenergetic parameters and performance. For male, v1500 was predicted by v a max , vOBLA, t lim at 110% of v a max , and CR (R 2 = 0.96). For female, no bioenergetic parameters were strongly correlated with v1500 m. The inverse relationship found between v a max and t lim at v a max in previous literature was confirmed by the 29 runners in this study and for the subset of male only.