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Meta-Analysis of Variation in Sport and Exercise Science

Examples of Application Within Resistance Training Research


  • James Steele Solent University
  • James P. Fisher Solent University
  • Dave Smith Manchester Metropolitan University
  • Brad J Schoenfeld CUNY Lehman College
  • Yefeng Yang University of New South Wales
  • Shinichi Nakagawa University of New South Wales



meta-analysis, intraindividual variability, variability, resistance training, applied statistics


Meta-analysis has become commonplace within sport and exercise science for synthesising and summarising empirical studies. However, most research in the field focuses upon mean effects; particularly the effects of interventions to improve outcomes such as fitness or performance. It is thought that individual responses to interventions vary considerably. Hence, interest has increased in exploring precision or personalised exercise approaches. Not only is the mean often affected by interventions, but variances may also be impacted. Exploration of variances in studies such as randomised controlled trials (RCTs) can yield insight into interindividual heterogeneity in response to interventions and help determine generalisability of effects. Yet, larger samples sizes than those used for typical mean effects are required when probing variances. Thus, in a field with small samples such as sport and exercise science, exploration of variance through a meta-analytic framework is appealing. Despite the value of embracing and exploring variation alongside mean effects in sport and exercise science it is rarely applied to research synthesis through meta-analysis.We introduce and evaluate different effect size calculations along with models for meta-analysis of variation using relatable examples from resistance training RCTs.


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2022-10-26 — Updated on 2023-09-15