Research

Hormonal

Two weeks of progressive resistance exercise significantly increases the fractional rate of quadriceps muscle protein synthesis in both young and elderly adults, effectively eliminating the age-related deficit in synthesis rate without increasing whole-body or myofibrillar protein breakdown.

Start resistance training immediately, regardless of age. Your muscles are just as capable of building protein as a young person's when you lift weights at a challenging intensity (60-90% of your max). You don't need supplements to trigger this early response; the mechanical load itself is the signal.

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These findings demonstrate that, during the initial phase of a resistance exercise training program, a marked increase in quadriceps muscle protein synthesis rate occurs in elderly and young adults without an increase in the rate of whole body protein breakdown.
Kevin E. Yarasheski et al. · American Journal of Physiology-Endocrinology and Metabolism · 1993

Why this rating

Controlled clinical study with stable isotope tracers, though small sample size (n=12).

Source

Acute effects of resistance exercise on muscle protein synthesis rate in young and elderly men and women

Kevin E. Yarasheski et al. · American Journal of Physiology-Endocrinology and Metabolism · 1993

DOI 10.1152/ajpendo.1993.265.2.e210

rct · n=12Cited 404×
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DOI resolved against Crossref · corpus check 2026-06-10

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