REPRODUCIBILITY OF RUNNING TIME TO EXHAUSTION AT VO2MAX IN SUBELITE RUNNERS

The purpose of this study was to assess the reproducibility of running time to exhaustion (Tlim) at maximal aerobic speed (MAS: the minimum speed that elicits VO2max), on eight subelite male long distance runne rs (29 +/- 3-yr-old; VO2max = 69.5 +/- 4.2 ml.kg(-1).min(-1); MAS = 21 .25 +/- 1.1 km.h(-1)). No significant differences were observed betwee n Tlim measured on a treadmill at a 1-wk interval (404 +/- 101 s vs 40 2 +/- 113 s; r = 0.864); however, observation of individual data indic ates a wide within-subjects variability (CV = 25%). In a small and hom ogenous sample of runners studied, exercise time to exhaustion at MAS was not related to VO2max (r = 0.138), MAS (r = 0.241), running econom y (mlO(2).kg(-1).min(-1) at 16 km.h(-1)) (r = 0.024), or running perfo rmance achieved for 3000 m (km.h(-1)) (r = 0.667). However, Tlim at MA S was significantly related to the lactate threshold determined by the distinctive acceleration point detected in the lactate curve around 3 -5 mmol.l(-1) expresses in %VO2max (r = 0.745) and to the speed over a 21.1-km race (km.h(-1)) (r = 0.719). These data demonstrate that runn ing time to exhaustion at MAS in subelite male long distance runners i s related to long distance performance and lactate threshold but not t o VO2max or MAS.