ملخص: ResumeL'objectif de cette etude est de comparer la depense energetique et ses limites en laboratoire et sur le terrain. Les variables utilisees sont la consommation d'oxygene, la vitesse maximale aerobie et la lactatemie, enregistrees lors d'epreuves classiques identiques, realisees en laboratoire (sur tapis roulant) et sur le terrain (piste d'athletisme). Dix huit sujets dont 13 coureurs de fond, volontaires (age = 26,4 [plus-or-minus sign]6,5 ans; poids = 65,1 [plus-or-minus sign] 7,0 kg ; taille = 172,9 [plus-or-minus sign] 5,2 cm) ont subi, a 1 semaine d'intervalle et dans un ordre aleatoire, deux epreuves l'une en laboratoire et l'autre sur le terrain. La consommation maximale d'oxygene (VO2 max) et la vitesse maximale aerobie (VMA) ont ete evaluees a l'aide d'un protocole triangulaire sur tapis roulant et sur piste d'athletisme. La consommation d'oxygene (VO2), le debit ventilatoire (VE) et la frequence cardiaque (FC) ont ete mesures au moyen d'un systeme telemetrique portable (K2 Cosmed). Les resultats indiquent que VMA est significativement plus basse sur le terrain (18,11 contre 19,78 km[middle dot]h-1, p 2 max de terrain est egalement inferieur (56,25 contre 61,93 mL[middle dot]min-1[middle dot] kg-1, p 2 max est plus indiquee en laboratoire sur tapis roulant, car une plus grande masse musculaire y est sollicitee. Mais pour la programmation de l'entrainement, il est preferable de se referer a VMA de terrain.SummaryIn long distance runners aerobic energy contribution is strongly predominant. VO2max and maximal aerobic speed (MAS) are generally measured on a treadmill to evaluate aerobic energy system. Various field tests have been proposed. Field tests are not always consistent with laboratory data; MAS is often better on treadmill and VO2max cannot been measured directly. The aim of this study is to compare aerobic metabolism measurements in laboratory and on the field, with the same methodology. VO2max, MAS, minute ventilation (VE) heart rate (HR) and onset of blood lactate accumulation (OBLA) have been assessed in laboratory and on the field by the mean of identical protocol (6 minutes warming up at 12 km[middle dot]hr-1, 3 minutes steps at increasing speed with 0% slope till exhaustion. Thirteen subjects of the study were long distance runners and five were students in sport education. VO2, VE were measured with a telemetric system (K2 Cosmed) in both experimental situations. MAS was higher on the treadmill (19.78 versus 18.11 km[middle dot]h-1, P 2max was higher on treadmill (61.93 versus 56.25 mL[middle dot]min-1[middle dot]kg-1, P 2max restriction on the field: lactatemia at MAS was identical in both situations; OBLA, in % VO2max was the same in both situations (85.48 [plus-or-minus sign] 4,04% versus 86.82 [plus-or-minus sign] 3.95%); energy cost of running at 60% MAS was higher on the field (170.25 [plus-or-minus sign] 14.02 versus 162.5 [plus-or-minus sign] 11.83 mL[middle dot]kg-1km-1, P 2max evaluation is better than field measurement because more muscles are working. But for training program field MAS evaluation is more adapted.

لغة: فرنسية