A meta-analysis to determine the dose response for strength development

Purpose: The identification of a quantifiable dose-response relationship for strength training is important to the prescription of proper training programs. Although much research has been performed examining strength increases with training, taken individually, they provide little insight into the magnitude of strength gains along the continuum of training intensities, frequencies, and volumes. A meta-analysis of 140 studies with a total of 1433 effect sizes (ES) was carried out to identify the dose-response relationship. Methods: Studies employing a strength-training intervention and containing data necessary to calculate ES were included in the analysis. Results: ES demonstrated different responses based on the training status of the participants. Training with a mean intensity of 60% of one repetition maximum elicits maximal gains in untrained individuals, whereas 80% is most effective in those who are trained. Untrained participants experience maximal gains by training each muscle group 3 d(.)wk(-1) and trained individuals 2 d(.)wk(-1). Four sets per muscle group elicited maximal gains in both trained and untrained individuals. Conclusion: The dose-response trends identified in this analysis support the theory of progression in resistance program design and can be useful in the development of training programs designed to optimize the effort to benefit ratio.