Effects of optimal power load strength training on kinetic and kinematic indicators: a systematic review and meta-analysis

Optimal power load strength training (OPLST) has been proposed as an effective strategy for integrating force and velocity characteristics to maximise power output. However, evidence regarding its effects on athletic performance remains inconsistent. Therefore, this study aimed to systematically evaluate the effects of OPLST on sprint time, jump height, one-repetition maximum (1RM), and peak power through a systematic review and meta-analysis. Five databases were searched. Seven studies were included, with four independent studies contributing to each outcome. Random-effects analyses were supplemented by within-study aggregation, sensitivity analyses, and exploratory comparisons of optimal power load determination, training background, and intervention duration. The original CMA estimates were − 0.162 for sprint time (95% CI − 0.441 to 0.117), 0.586 for jump height (0.287 to 0.886), 0.368 for 1RM (0.038 to 0.697), and 0.208 for peak power (− 0.007 to 0.423; p = 0.058). After within-study aggregation with an assumed correlation of 0.50, estimates were − 0.187 (− 0.532 to 0.159), 0.581 (0.192 to 0.971), 0.355 (− 0.026 to 0.736), and 0.239 (− 0.088 to 0.566), respectively. Small-sample interval and influence analyses further limited confidence in statistical significance. Exploratory comparisons did not establish a reliable moderator effect. The most consistent positive signal concerned jump height; evidence for 1RM was sensitive to analytical assumptions, and differences in sprint time and peak power were not statistically established. Few studies, variable interventions and comparators, and uncertain reporting bias limit certainty and generalisability. https://www.crd.york.ac.uk/prospero , identifier: CRD42024510488.