The Effect Of 8-week Lower Extremity Ballistic Training Program On Block Jump Performance In Male Volleyball Players

Objective: The purpose of this study was to explore the effect of two different ballistic training programs on lower extremity muscle power and block jump performance in male volleyball players.Methods:Fourteen(n=14)male elite atheltes,from volleyball team in Beijing Sport University,volunteered to participate in this study.All subjects were divided into treatment group and control group ramdomly.Treatment group performed 8 weeks,2 times per week squat jump combined with Cormax ballistic training machine and discontinuous block jump training consisting of 6 sets of 6 reps at their 30%1RM.Control group perform the same program with treatment group.The only different training was not using the Cormax ballistic machine when squat jump.The half squat jump output power and motion speed when loaded 20,30,40 and 50 kg were recorded using Tendo Unit system.The height of half squat jump,contermovement jump and block jump were recorded using Kistler 3D force plate.Smartspeed tachymeter was used to measure the reaction time when block jump.Independent sample t-test and paired sample t-test were analyzed using SPSS 17.0 software.Results:(1)Squat jump output power and motion speed in treatment group were lower than control group.Output power increased along with the increased load and motion speed increased with decreased load.(2)Statistically significant increases were found in right leg contermovement jump height(0.174±0.059 m,P<0.05)after training in treatment group.Treatment group and control group increased their contermovement jump and block jump height.And Squat Jump height decreased in treatment group and in control group.(3)The block jump reaction time decreased by 0.068±0.089 s in treatment group and 0.047±0.084 s in control group.Conclusions:(1)No Eccentric Contraction of ballistic squat jump training was lower than traditional squat jump in output power and motion speed when using the same load.(2)There was no significant difference in vertical jump height for the two different ballistic training program during.And ballistic training without eccentric contraction phase increased nondominant leg vertical jump height effectively.(3)There were no significant differences in block jump height and reaction time between ballistic training and traditional training.