Is Training Transfer Uniform? A Systematic Review and Three-Level Meta-Analysis of Resisted Sprint Training Effects...

Resisted sprint training (RST) is widely used to improve acceleration, but transfer to jumping and changing direction remains unclear. This review examined RST effects on acceleration, vertical and horizontal jump, and change of direction performance, with variation by comparator and training characteristics. Eight databases were searched to 7 July 2026. The review included 66 independent studies and 1945 participants; 31 controlled studies contributed 179 effect sizes to the primary analysis. Three-level random-effects models accounted for dependence within studies. RST favored acceleration (g = 0.32, 95% CI [0.16, 0.49]), vertical jump (g = 0.25, 95% CI [0.06, 0.44]), horizontal jump (g = 0.24, 95% CI [0.11, 0.37]), and change of direction performance (g = 0.46, 95% CI [0.09, 0.82]). Prediction intervals crossed zero for acceleration, vertical jump, and change of direction performance, but not horizontal jump. After adjustment for comparator type, effects did not clearly differ among domains (p = 0.699). Compared with unresisted sprint training, additional mean effects were small (g = 0.22-0.30). Exploratory moderator analyses found no clear associations with comparator type, external load, training dose, or RST modality. GRADE certainty was moderate for acceleration and low for other outcomes. RST showed favorable mean effects across all four domains, although benefits in new training contexts remain uncertain. Evidence identifies no universal load, dose, or superior modality, and the predominantly male evidence base limits generalizability to female athletes. RST is best viewed as a targeted overload method complementing sprinting at high speed and training specific to the task.