Comparable rates of integrated myofibrillar protein synthesis between endurance-trained master athletes and untrained older individuals

Research output: Contribution to journalArticle


Colleges, School and Institutes

External organisations

  • Department of Kinesiology; McMaster University; Hamilton ON CA
  • NIHR Birmingham Biomedical Research Centre
  • MRC-Arthritis Research UK Centre for Musculoskeletal Ageing Research, University of Birmingham, Birmingham, England, UK


Background: An impaired muscle anabolic response to exercise and protein nutrition isthought to underpin age-related muscle loss, which may be exacerbated by aspects ofbiological aging that may not be present in older individuals who have undertaken long-term high-level exercise training, or master athletes (MA). The aim of this study was to compare rested-state and exercise-induced rates of integrated myofibrillar protein synthesis (iMyoPS) and intracellular signaling in endurance trained MA and healthy age-matched untrained individuals (Older Controls).

Methods: In a parallel study design, iMyoPS rates were determined over 48 h inthe rested-state and following a bout of unaccustomed resistance exercise (RE) inOC (n = 8 males; 73.5 3.3 years) and endurance-trained MA (n = 7 males;68.9 5.7 years). Intramuscular anabolic signaling was also determined. During theiMyoPS measurement period, physical activity was monitored via accelerometry anddietary intake was controlled.

Results: Anthropometrics, habitual activity, and dietary intake were similar betweengroups. There was no difference in rested-state rates of iMyoPS between OC(1.47 0.06%day&#x100000;1) and MA (1.46 0.08%day&#x100000;1). RE significantly increased iMyoPS above rest in both OC (1.60 0.08%day&#x100000;1, P < 0.01) and MA (1.61 0.08%day&#x100000;1,P < 0.01), with no difference between groups. AktThr308 phosphorylation increased at1 h post-RE in OC (P < 0.05), but not MA. No other between-group differences inintramuscular signaling were apparent at any time-point.

Conclusion: While our sample size is limited, these data suggest that rested-state andRE-induced iMyoPS are indistinguishable between MA and OC. Importantly, the OCretain a capacity for RE-induced stimulation of skeletal muscle remodeling.


Original languageEnglish
Pages (from-to)1084
Number of pages10
JournalFrontiers in Physiology
Publication statusPublished - 30 Aug 2019


  • muscle, anabolism, master athlete, resistance exercise, sarcopenia