Role of excitation-contraction coupling in muscle fatigue
Deutscher übersetzter Titel: | Bedeutung der Erregungs-Kontraktions-Kopplung fuer die Muskelermuedung |
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Autor: | Allen, D.G.; Westerblad, H.; Lee, J.A.; Laennergren, J. |
Erschienen in: | Sports medicine |
Veröffentlicht: | 13 (1992), 2, S. 116-126, Lit. |
Format: | Literatur (SPOLIT) |
Publikationstyp: | Zeitschriftenartikel |
Medienart: | Gedruckte Ressource Elektronische Ressource (online) |
Sprache: | Englisch |
ISSN: | 0112-1642, 1179-2035 |
DOI: | 10.2165/00007256-199213020-00007 |
Schlagworte: | |
Online Zugang: | |
Erfassungsnummer: | PU199207057143 |
Quelle: | BISp |
Abstract
The force produced by muscles declines during prolonged activity and this decline arises largely from processes within the muscle. At a cellular level the reduced force could be caused by: a) reduced intracellular calcium release during activity; b) reduced sensitivity of the myofilaments to calcium; or c) reduced maximal force development. Experiments involving intracellular calcium measurements in isolated single fibres show that all 3 of the above contribute to the decline of force during fatigue. Metabolic changes associated with fatigue are probably involved in each of the 3 factors. Thus the accumulation of phosphate and protons which occur during fatigue cause a reduction in calcium sensitivity and a decline in maximal force. The cause of the reduced intracellular calcium during contractions in fatigue is less clear. During prolonged tetani the conduction of the action potential in the T-tubules appears to fail leading to reduced intracellular calcium in the central part of the muscle fibre. However, during repeated tetani there is a uniform decline of intracellular calcium across the fibre and this remains one of the least understood processes which contribute to fatigue. Verf.-Referat