Knee extensor fatigability and strength after bicycle ergometer training.

The objective of this research was to study the effect of a 10-week bicycle-ergometer training program on the strength of knee extension and vastii muscles fatigability in male subjects with no knee pathology. Subjects performed maximum effort isometric knee extension at 60 degrees of knee flexion. Fatigue rates of vastii muscles were evaluated by quantifying myoelectric power density spectrum changes during a 1-minute dynamic (concentric/eccentric) knee exercise. Maximal oxygen uptake as well as muscle efficiency increased (p < .01), indicating positive changes in physical fitness and neuromuscular adaptation in muscles. The endurance of knee extensors increased (p < .001-.05) whereas their maximal short-term force decreased (p < .01-.05). Training response was greater (p < .01-.05) in vastus medialis than in vastus lateralis muscle. This effect encourages to use bicycle ergometer in knee rehabilitation programs.