Research

Hormonal

Aging causes anabolic resistance to protein intake, characterized by a blunted muscle protein synthetic response to amino acids, which contributes to sarcopenia.

As you age, your muscles become less sensitive to protein. To build or maintain muscle, you likely need to consume more protein per meal (specifically leucine-rich sources) or time it precisely around exercise, rather than just eating the standard amount spread out.

GoodSupportsHIGH confidence
Recent studies suggest that the muscle protein synthetic response to food intake is blunted in the elderly. The latter is now believed to represent a key factor responsible for the age-related decline in skeletal muscle mass.
René Koopman et al. · Journal of Applied Physiology · 2009

Why this rating

Based on a review of multiple studies showing consistent findings of blunted response, though mechanisms are still being elucidated.

Source

Aging, exercise, and muscle protein metabolism

René Koopman et al. · Journal of Applied Physiology · 2009

DOI 10.1152/japplphysiol.91551.2008

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DOI resolved against Crossref · corpus check 2026-06-10

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