A comparison of peak and constant angle torque-velocity curves in fast and slow-twitch populations.

Peak and constant angle torque-velocity (T-V) curves were measured on a group of fast-twitch (FT, n = 10) and slow-twitch (ST, n = 6) subjects using a Cybex dynamometer. The T-V curve was plotted from 10 randomly assigned velocities ranging from 0.52 to 5.24 rad s-1 (30 to 300 degrees s-1). Each subject was tested four times with at least 24 h between testing sessions. Torque-velocity curves were plotted from the peak torque generated throughout the range of motion and from torque produced at a constant angle (150 degrees). When all subjects were combined into a single group, no significant difference existed between the normalized T-V curves even though they differed significantly in absolute amounts. When subjects were grouped according to muscle fiber type the T-V curves produced from constant angle torque differed significantly while those generated from peak torque did not. This finding suggests that T-V curves generated from peak torque are not as sensitive to influences produced by muscle fiber type as those curves generated from constant angle torque.