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Updated: Jul 8, 2026
14:02
Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
Skeletal muscle fatigue: cellular mechanisms
D G Allen1, G D Lamb, H Westerblad
1School of Medical Sciences and Bosch Institute, University of Sydney, Sydney, New South Wales, Australia. davida@physiol.usyd.edu.au
Physiological Reviews
|January 16, 2008
Summary
Muscle fatigue, a decline in performance from intense exercise, involves complex mechanisms beyond lactate accumulation. Ionic changes, impaired calcium release, and reactive oxygen species are key factors influencing muscle function.
Area of Science:
- Exercise Physiology
- Muscle Biology
- Biochemistry
Background:
- Muscle fatigue is a complex physiological response to strenuous activity.
- Traditional explanations involving lactate and hydrogen ions may be less significant in mammals.
- Understanding fatigue mechanisms is crucial for athletic performance and disease management.
Purpose of the Study:
- To explore the multifaceted mechanisms underlying muscle fatigue.
- To evaluate alternative explanations for performance decline beyond traditional theories.
- To bridge the gap between isolated tissue studies and fatigue in intact organisms.
Main Methods:
- Review of existing literature on muscle fatigue mechanisms.
- Analysis of changes in action potentials, ion concentrations, and metabolites during fatigue.
- Examination of the roles of sarcoplasmic reticulum calcium release and reactive oxygen species.
Main Results:
- Intracellular lactate and hydrogen ion accumulation has limited impact on mammalian muscle function.
- Ionic shifts affecting action potentials contribute to fatigue.
- Dysfunctional sarcoplasmic reticulum calcium release and reactive oxygen species are significant factors.
Conclusions:
- Muscle fatigue involves a range of mechanisms, including ionic disturbances and impaired calcium handling.
- Identifying specific fatigue contributors under various conditions remains a challenge.
- Translating findings from animal models to human physiology and disease is essential.
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