This study aimed to assess the effects of jump training (JT) on the jumping performance of handball players compared with a control condition. The data sources utilised were PubMed, MEDLINE, Web of Science Core Collection, and SCOPUS. Only peer-review randomised controlled trials were included. The inclusion criteria comprised: a JT programme of at least 2 weeks; a control group; the assessment of the countermovement jump (CMJ). The Physiotherapy Evidence Database scale was used to assess the risk of bias and methodological quality of eligible studies included in the meta-analysis. Risk of publication bias across studies was assessed using the extended Egger’s test. Cohen`s d effect sizes (ESs) were calculated from the CMJ and presented together with 95% confidence intervals (CIs). From 6108 records initially identified through database searching, 5 were eligible for meta-analysis. A significant improvement in CMJ height was observed, corresponding to 6.4 cm (95%CI=4.9-7.9; Z=8.4, p <0.001), showing moderate heterogeneity (I2=51.4%). The magnitude of the main effect was very large (ES=2.2 [95%CI=0.95-3.4], Z=3.5, p < 0.001). JT is effective in increasing vertical jump performance in handball players. However, the insufficient number of studies conducted precluded analyses of moderator variables. In future, researchers are advised to conduct JT studies of high methodological quality (e.g., randomized controlled trials) and assess different jump exercise prescriptions across handball players of different sexes, ages, and competitive levels to analyse if exercise prescription and player characteristics may influence training responses.
Fonte: International Journal of Sports Science and Coaching, in press, 2020.