Effects of aerobic exercise on the torque-velocity relationship in cycling |
| |
Authors: | O. Buttelli H. Vandewalle J. C. Jouanin D. Seck H. Monod |
| |
Affiliation: | (1) Laboratoire de Physiologie du Travail et du Sport, 91 bd de l'H?pital, F-75634 Paris Cedex 13, France, FR;(2) Centre Médico-Sportif, Ecole Interarmées des Sports. F-77307 Fontainebleau Cedex, France, FR |
| |
Abstract: | The kinetics of the torque-velocity (T-ω) relationship after aerobic exercise was studied to assess the effect of fatigue on the contractile properties of muscle. A group of 13 subjects exercised until fatigued on a cycle ergometer, at an intensity which corresponded to 60% of their maximal aerobic power for 50 min (MAP60%); ten subjects exercised until fatigued at 80% of their maximal aerobic power for 15 min (MAP80%). Of the subjects 7 exercised at both intensities with at least a 1-week interval between sessions. Pedalling rate was set at 60 rpm. The T-ω relationship was determined from the velocity data collected during all-out sprints against a 19 N · m braking torque on the same ergometer, according to a method proposed previously. Maximal theoretical velocity (ω0) and maximal theoretical torque (T 0) were estimated by extrapolation of the linear T-ω relationship. Maximal power (P max) was calculated from the values of T 0 and ω0 (P max = 0.25 ω0 T 0). The T-ω relationships were determined before, immediately after and 5 and 10 min after the aerobic exercise. The kinetics of ω0, T 0 and P max was assumed to express the effects of fatigue on the muscle contractile properties (maximal shortening velocity, maximal muscle strength and maximal power). Immediately after exercise at MAP60% a 7.8% decrease in T 0 and 8.8% decrease in P max was seen while the decrease in ω0 was nonsignificant, which suggested that P max decreased in the main because of a loss in maximal muscle strength. In contrast, MAP80% induced a 8.1% decrease in ω0 and 12.8% decrease in P max while the decrease in T 0 was nonsignificant, which suggested that the main cause of the decrease in P max was probably a slowing of maximal shortening velocity. The short recovery time of the T-ω relationship suggests that the causes of the decrease of torque and velocity are processes which recover rapidly. Accepted: 25 November 1996 |
| |
Keywords: | Fatigue Aerobic Exercise Cycling |
本文献已被 SpringerLink 等数据库收录! |
|