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Updated: May 10, 2026
14:02
Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
Skeletal muscle fatigue
Jane A Kent-Braun1, Robert H Fitts, Anita Christie
1Department of Kinesiology, University of Massachusetts-Amherst, Amherst, Massachusetts, USA. janekb@kin.umass.edu
Comprehensive Physiology
|June 27, 2013
Summary
Skeletal muscle fatigue, a decline in force or power during activity, has diverse mechanisms and measurement methods. Understanding its molecular to organismal basis aids in identifying disease-related dysfunction.
Area of Science:
- Physiology
- Exercise Science
- Pathology
Background:
- Skeletal muscle fatigue is a critical factor limiting physical performance.
- The mechanisms underlying muscle fatigue are complex and multifaceted.
- Understanding fatigue is essential for both athletic performance and clinical applications.
Purpose of the Study:
- To define skeletal muscle fatigue and its variability.
- To highlight the range of mechanisms and methods for studying fatigue.
- To explore the role of fatigue in disease states.
Main Methods:
- Examining fatigue from molecular to whole-organism levels.
- Utilizing conceptual and technological advancements in research.
- Evaluating muscle fatigue across various disease conditions.
Main Results:
- Fatigue mechanisms and elicitation modes show significant variation.
- Advances enable comprehensive analysis of fatigue.
- Disease states reveal specific sources of muscle dysfunction.
Conclusions:
- Skeletal muscle fatigue is characterized by reduced force/power output.
- Research approaches span multiple biological scales.
- Studying fatigue in disease provides insights into pathophysiology.
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