筋力トレーニングが筋線維伝導速度に及ぼす影響  [in Japanese] THE EFFECTS OF STRENGTH TRAINING ON MUSCLE FIBER CONDUCTION VELOCITY OF SURFACE ACTION POTENTIAL  [in Japanese]

We investigated the effects of strength training a muscle fiber conduction velocity in biceps brachii of 7 male students. The subjects were trained to exhaustion by 60% of maximum isotonic voluntary contraction with 3 sets/day, 3 days/week for 16 weeks. The muscle fiber conduction velocity was measured with a surface electorode array placed along the muscle fibers, and calculated from the time delay between 2 myoelectric signals recorded during a maximal voluntary contraction. Upper arm girth significantly increased (p < 0.01), from 29.2±1.4cm (means±S.D.) to 30.6±1.5cm. On the other hand, training induced no significant changes in upper arm skinfold. A significant difference between pre-and post-training was found in maximum isotonic strength (p < 0.01). Although maximum isometric strength showed no significant changes with training, there was a tendency for an increase in maximum isometric strength. Muscle fiber conduction velocity increased by 3.5% during training period, but this was not significant. These results suggest no effects of strength training on muscle fiber conduction velocity.