Effects of plyometric training on jumping performance in junior basketballplayers

Background. Although the plyometric training has proved its efficiency, it remains generally unknown whether a limited amount of plyometric training c ould improve movements in subjects who already demonstrate high level of pe rformance. Methods. Three different training regimens were performed in order to study effects of plyometric training on elite junior basketball players. While c ontrol group (CG) participated only in the regular midseason training activ ity, another two groups performed a limited amount of plyometric training e mploying drop jumps from the height of either 50 cm (EG-50) or 100 cm (EG-1 00). The height of the maximal vertical jump (CMJ), as well as the maximal voluntary force (F) and the rate of force development (RFD) of hip and knee extensors were tested prior to and after the training. Results. An increase in CMJ (4.8 and 5.6 cm in EG-50 and EG-100, respective ly), as well as in F of hip extensors and RFD of knee extensors was observe d in both experimental groups, while no significant changes were recorded i n CG. When the pretest scores were used as a covariate, both experimental g roups demonstrated higher increase in CMJ and RFD of knee extensors then CG . However, no differences were observed between EG-50 and EG-100. The multi ple correlation between four isometric parameters and CMJ revealed R-2=0.29 . Conclusions. A limited amount of plyometric training could improve jumping performance in elite junior basketball players and this improvement could b e partly related with an increase in F of hip extensors and RFD of knee ext ensors. However, neither of the two initial heights of the applied drop jum ps proved to be more effective.