Training effects on muscle fatigue in man

Abstract
Effects of 3 months training, on electrical and mechanical failures during fatigue, were studied in human adductor pollicis muscle. Eight subjects carried out a daily training program of 10 series of 20 fast (0.5 s) voluntary contractions, against a load equivalent to 30–40% of the muscle maximal force. Contractile properties in control and trained muscles are tested by delivering supramaximal electrical pulses (30 Hz) to the motor nerve, thereby triggering series of 60 1-s contractions separated by 1-s intervals. Training produces significant increase in tension development during a 30 Hz isometric tetanus (+13%;PPPPP<0.01) reduces augmentation of muscle SAP duration and area recorded during fatigue. Comparison of time courses of mechanical and electrical failures in control and trained muscles, supports the idea that intracellular processes play the major role in tension decay associated with fatigue in human adductor pollicis muscle.