Standard Deviation of Individual Response for VO Following Exercise Interventions: A Systematic Review and Meta-analysis.

BACKGROUND

Although numerous attempts to demonstrate inter-individual differences in trainability across various outcomes have been unsuccessful, the investigation of maximal oxygen consumption (VO) trainability warrants further study.

OBJECTIVE

Our objective was to conduct the first systematic review and meta-analysis to evaluate inter-individual differences in VO trainability across aerobic exercise training protocols utilizing non-exercising comparator groups.

METHODS

We conducted a literature search across three databases: EMBASE, PubMed and SCOPUS. The search strategy incorporated two main concepts: aerobic exercise training and VO. Studies were included if they used human participants, employed standardized and supervised exercise training, reported absolute or relative VO, included a non-exercise comparator group, reported VO change scores for non-exercise and exercise groups and provided the standard deviation (SD) of change for all groups. We calculated the SD of individual response (SD) to estimate the presence of inter-individual differences in trainability across all studies.

RESULTS

The literature search generated 32,968 studies, 24 of which were included in the final analysis. Our findings indicated that (1) the majority of variation in observed change scores following an intervention is due to measurement error, (2) calculating SD within a single study would not yield sufficient accuracy of SD due to generally small sample sizes and (3) meta-analysis of across studies does not provide strong evidence for a positive value.

CONCLUSION

Overall, our meta-analysis demonstrated that there is not strong evidence supporting the existence of VO trainability across single interventions. As such, it appears unlikely that clinically relevant predictors of VO response will be discovered. Registration can be found online ( https://doi.org/10.17605/OSF.IO/X9VU3 ).