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Review on aging, unloading and reloading: changes in skeletal muscle quantity and quality
Teet Seene1, Priit Kaasik, Eva-Maria Riso
1Institute of Exercise Biology and Physiotherapy, University of Tartu, Ülikooli 18, 50090 Tartu, Estonia. teet.seene@ut.ee
Archives of Gerontology and Geriatrics
|June 3, 2011
Summary
Aging and muscle unloading reduce muscle mass and function. While reloading can help, age-related changes complicate full recovery of skeletal muscle strength and structure.
Area of Science:
- Gerontology
- Skeletal Muscle Physiology
- Exercise Science
Background:
- Aging and muscle unloading lead to decreased muscle mass, structure, and force.
- Skeletal muscle exhibits altered mechanical properties with age and disuse.
- Regeneration capacity varies between intra- and extra-cellular compartments, impacting recovery.
Purpose of the Study:
- To review studies on aging skeletal muscle during unloading and reloading.
- To highlight age-dependent changes in muscle mass, structure, and function.
- To examine the role of the extracellular matrix (ECM) and protein metabolism in recovery.
Main Methods:
- Literature review of studies on aging skeletal muscle.
- Analysis of changes in muscle mass, architecture, and mechanical properties.
- Examination of factors influencing muscle regeneration and adaptation.
Main Results:
- Muscle unloading and aging significantly impair muscle mass, strength, and locomotion.
- Extracellular matrix (ECM) components undergo changes affecting muscle properties.
- Age-related susceptibility to damage impacts the contractile machinery and recovery potential.
Conclusions:
- Full restoration of muscle architecture and function after unloading is challenging in aging individuals.
- Differences in regenerative capacity and age-related damage complicate the understanding of recovery.
- Further research is needed to optimize interventions for aging muscle health.
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