Abstract des Autors

In order to assess the relative contribution of aerobic processes to running velocity (v), 27 male athletes were selected on the basis of their middle-distance performances over 800, 1500, 3000 or 5000 m. To be selected for study, the average running velocity (-v) corresponding to their performances had to be superior to 90 of the best French -v of the season. VO2max and energy cost of running (C) had been measured within the 2 months preceding the track season, which, together with oxygen consumption at rest (Vo2rest) allowed us to calculate the maximal v that could be sustained under aerobic conditions: vamax = (VO2max - VO2rest) x 1/C. The treadmill running v corresponding to a blood lactate of 4 mmol/l (v1a4), was also calculated. In the whole group, C was significantly related to height. Neither C nor VO2max (with the exception of the 3000 m athletes) were correlated to -v. On the other hand, vamax was significantly correlated to -v over distances longer than 800 m. These -v were also correlated to v1a4. However v1a4 occurred at 87.5 SD 3.3 of vamax, this relationship was interpreted as being an expression of the correlation between vamax and -v. Calculation of vamax provided a useful means of analysing the performances. At the level of achievement studied, -v sustained over 3000 m corresponded to vamax. The shape of the relationship of v/vamax as a function of the duration of the event raised the question of a possible change in C as a function of v during middle-distance running competitions.