Research

Hormonal

Age-related sarcopenia is driven by a combination of motor unit loss, fiber atrophy (specifically Type II), inflammatory cytokine expression, and hormonal declines (IGF-1, testosterone).

Understanding that muscle loss is biological (hormonal/inflammatory) helps explain why it happens, but it does not negate the effectiveness of exercise as a treatment.

StrongSupportsHIGH confidence
The underlying cellular changes involve weakening of factors promoting muscle anabolism and increased expression of inflammatory factors and other agents which contribute to skeletal muscle catabolism.
Thomas Lang et al. · Osteoporosis International · 2009

Why this rating

The paper is a review summarizing extensive literature on these mechanisms.

Source

Sarcopenia: etiology, clinical consequences, intervention, and assessment

Thomas Lang et al. · Osteoporosis International · 2009

DOI 10.1007/s00198-009-1059-y

narrative_reviewCited 787×
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DOI resolved against Crossref · corpus check 2026-06-10

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