Related Experiment Video
Updated: Apr 17, 2026

Ex Vivo Assessment of Contractility, Fatigability and Alternans in Isolated Skeletal Muscles
Published on: November 1, 2012
Skeletal muscle fatigue and decreased efficiency: two sides of the same coin?
Bruno Grassi1, Harry B Rossiter, Jerzy A Zoladz
11 Exercise Physiology Laboratory, Department of Medical and Biological Sciences, University of Udine, Udine, Italy; 2 Division of Respiratory and Critical Care Physiology and Medicine, Los Angeles Biomedical Research Institute at Harbor UCLA Medical Center, Torrance, CA; and 3 Department of Muscle Physiology, Chair of Physiology and Biochemistry, Faculty of Rehabilitation, University School of Physical Education, Kraków, Poland.
Abstract:
During high-intensity submaximal exercise, muscle fatigue and decreased efficiency are intertwined closely, and each contributes to exercise intolerance. Fatigue and muscle inefficiency share common mechanisms, for example, decreased "metabolic stability," muscle metabolite accumulation, decreased free energy of adenosine triphosphate breakdown, limited O2 or substrate availability, increased glycolysis, pH disturbance, increased muscle temperature, reactive oxygen species production, and altered motor unit recruitment patterns.
Related Concept Videos
Muscle Recovery and Fatigue
Disorders of the Skeletal Muscle
Musculoskeletal disorders
Musculoskeletal disorders involve injuries and conditions affecting the skeletal muscles and associated connective tissues. These disorders can arise from acute biomechanical stresses or chronic overuse and can occur across different age groups. Common injuries include sprains, fractures, and muscular strains, often resulting from...
Cross-bridge Cycle
Energy Supply for Muscle Contraction
Exercise and Muscle Performance
Endurance exercises
Endurance exercises involve running, swimming, or cycling, which require repetitive movements with low force output. When a person engages in endurance exercise, a few noticeable changes occur in their skeletal muscles. For instance, the number of capillaries...
Fatigue

