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Muscle fibre denervation in ageing
1The August Krogh Section for Human Physiology, Department of Nutrition, Exercise and Sports, University of Copenhagen, Copenhagen, Denmark.
Clinical Science (London, England : 1979)
|June 10, 2026
Summary
Muscle fibre denervation, the loss of neural input to muscles, contributes to age-related strength decline. Defining and measuring this complex process in humans requires multiple approaches.
Area of Science:
- Neurology
- Gerontology
- Muscle Physiology
Background:
- Muscle fibre denervation, the loss of neural input to muscle fibers, is a key factor in age-related muscle weakness.
- Current understanding and measurement of denervation in humans are limited by complexity and methodological challenges.
Purpose of the Study:
- To review human evidence on muscle fibre denervation in aging.
- To clarify conceptual distinctions and evaluate assessment methods for denervation in humans.
- To synthesize current knowledge for preserving neuromuscular function.
Main Methods:
- Review of histological, molecular, electrophysiological, and circulating biomarker studies in humans.
- Analysis of experimental disuse models in humans.
- Evaluation of physical activity's mitigating effects.
Main Results:
- Denervation can result from structural or functional neuromuscular transmission impairment.
- Multiple methods capture different aspects of neuromuscular integrity; no single measure is comprehensive.
- Disuse models show functional denervation phenotypes similar to aging.
- Physical activity may counteract denervation, but mechanisms are unclear.
Conclusions:
- Age-related denervation is a complex, dynamic process.
- Multimodal, longitudinal studies are essential for accurate assessment and targeted interventions.
- Understanding denervation is crucial for maintaining neuromuscular function throughout life.
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