Research

Hormonal

Long-term high-level endurance training does not preserve or enhance the capacity for myofibrillar protein synthesis (iMyoPS) in response to unaccustomed resistance exercise in older adults compared to untrained age-matched peers.

If you are an older adult who has done endurance sports for decades, don't assume your muscles will automatically build or maintain mass when you start lifting weights. Your history of running or cycling does not protect you from 'anabolic resistance' to resistance exercise. You likely need to approach resistance training with the same diligence as an untrained peer, focusing on progressive overload and adequate protein intake, as your chronic training history offers no special advantage in muscle protein synthesis rates.

ModerateRefutesMEDIUM confidence
these data suggest that rested-state and RE-induced iMyoPS are indistinguishable between MA and OC. Importantly, the OC retain a capacity for RE-induced stimulation of skeletal muscle remodeling.
James McKendry et al. · Frontiers in Physiology · 2019

Why this rating

Small sample size (n=15 total) and short duration (48h measurement), but rigorous methodology (isotope tracing, controlled diet).

Source

Comparable Rates of Integrated Myofibrillar Protein Synthesis Between Endurance-Trained Master Athletes and Untrained Older Individuals

James McKendry et al. · Frontiers in Physiology · 2019

DOI 10.3389/fphys.2019.01084

rct · n=15Cited 25×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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