title: Fatigue of long duration in human skeletal muscle after exercise.
abstract: 1. After severe muscular contraction in man recovery of force is largely complete in a few minutes, but is not wholly so for many hours. The long-lasting element of fatigue is found to occur primarily for low frequencies of stimulation (e.g. 20/sec), and is much less pronounced, or absent, at high frequencies (80/sec). The twitch force is an unreliable measure of the state of fatigue. 2. The long-lasting element of fatigue is not due to depletion of high-energy phosphate nor is it due to failure of electrical activity as recorded from surface electrodes. It is probably the result of an impairment of the process of excitation-contraction coupling. Its practical importance for man could be significant as an explanation of the subjective feelings of weakness following exercise.
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D005221:Fatigue / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009119:Muscle Contraction; D009132:Muscles / Q000378:metabolism / Q000502:physiology*; D010725:Phosphocreatine / Q000378:metabolism; D005082:Physical Exertion; D013997:Time Factors
chemical_list: D010725:Phosphocreatine; D000255:Adenosine Triphosphate