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Lower integrated muscle protein synthesis in masters compared with younger athletes
Medicine and Science in Sports and Exercise (2016)
  • Thomas M Doering, Central Queensland University
  • David G Jenkins, Central Queensland University
  • Peter Reaburn, Central Queensland University
  • Nattai R Borges, Central Queensland University
  • Erik Hohmann
  • Stuart M Phillips, McMaster University

The objective of this study is to compare the integrated muscle protein synthesis (MPS) rates of masters and younger triathletes over three consecutive days of intense endurance training. Recovery of cycling performance, after muscle-damaging running, was also compared between groups.


Five masters (age, 53 ± 2 yr; V˙O2max, 55.7 ± 6.9 mL·kg·min) and six younger (age, 27 ± 2 yr; V˙O2max, 62.3 ± 1.5 mL·kg·min) trained triathletes volunteered for the study. Baseline skeletal muscle and saliva were initially sampled, after which a 150-mL bolus of deuterium oxide (70%) was consumed. Participants then completed a 30-min downhill run; three 20-km cycling time trials (TT) were completed 10, 24, and 48 h after the run. Saliva was collected each morning, and skeletal muscle was again sampled 72 h after the run; both were used for MPS analysis. Diet was controlled throughout the study.


Over 3 d, masters triathletes showed a significantly lower myofibrillar fractional synthetic rate (1.49% ± 0.12%·d) compared with the younger (1.70% ± 0.09%·d) triathletes (P = 0.009, d = 1.98). There was also a trend for masters triathletes to produce a slower cycle TT (-3.0%, d = 0.46) than younger triathletes (-1.4%, d = 0.29) at 10 h postrun in comparison with the baseline performance. The between-group comparison of change was moderate (d = 0.51), suggesting slower acute recovery among masters triathletes.


The present data show lower MPS rates in well-trained masters triathletes over 3 d of training, and this likely contributes to poorer muscle protein repair and remodeling. Furthermore, acute recovery of cycle TT performance tended to be poorer in the masters triathletes.
Publication Date
August, 2016
Publisher Statement
Citation only

Doering, T., Jenkins, D., Reaburn, P., Borges, N., Hohmann, E. & Phillips, S. (2016). Lower integrated protein synthesis in masters compared to younger athletes. Medicine and Science in Sports and Exercise, 48(8), 1613-1618.

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Copyright © 2016 by the American College of Sports Medicine

This document has been peer reviewed.
Citation Information
Thomas M Doering, David G Jenkins, Peter Reaburn, Nattai R Borges, et al.. "Lower integrated muscle protein synthesis in masters compared with younger athletes" Medicine and Science in Sports and Exercise Vol. 48 Iss. 8 (2016) p. 1613 - 1618 ISSN: 0195-9131
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