Research

Hormonal

Aging impairs contraction-induced mTORC1 signaling and muscle protein synthesis (MPS) in skeletal muscle, leading to a blunted hypertrophic response to resistance exercise compared to young adults.

For older adults, standard resistance exercise may not trigger the same muscle-building signals (mTORC1) as it does in younger people. This biological impairment contributes to slower muscle growth. To counteract this, older adults may need to focus on higher-intensity resistance training or combine exercise with specific nutritional strategies (like protein intake) to help stimulate the mTORC1 pathway, as the natural response is blunted by aging.

GoodRefutesHIGH confidence
We conclude that aging impairs contraction-induced human skeletal muscle mTORC1 signaling and protein synthesis. These age-related differences may contribute to the blunted hypertrophic response seen after resistance-exercise training in older adults...
Christopher S. Fry et al. · Skeletal Muscle · 2011

Why this rating

Randomized controlled comparison between young and older adults with detailed time-course molecular analysis and stable isotope tracing for MPS; however, it is a single study with a small sample size (n=32).

Source

Aging impairs contraction-induced human skeletal muscle mTORC1 signaling and protein synthesis

Christopher S. Fry et al. · Skeletal Muscle · 2011

DOI 10.1186/2044-5040-1-11

mechanism_only · n=32Cited 350×
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DOI resolved against Crossref · corpus check 2026-06-10

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