The Effect Of Postactivation Potentiation On Vertical Jump Performance After The Back Squat Exercises With Different Load, Resting Interval And Depth

Postactivation potentiation (PAP) is believed to be a series of muscle contraction history generated by human muscle acute power output, also known as “contraction memory” which is able to potentiate muscle contraction performance subsequently.The purpose of this study including find the best exercise to induce PAP and improving countermovement jump (CMJ) performance and the optimum intensity, knee angel and resting interval and their best combination. Ultimately help coaches and athletes better design their pregame warm-up protocol.12participants voluntarily participated in this study. Before every testing session, a fatigue level evaluation was performed and only if the result was positive, the testing session would continue.5minutes jogging was implemented first, dynamic stretching was utilized right after jogging, then one of the following testing protocol was randomly performed.80%1RM-90degree squat,80%1RM-120degree squat,85%1RM-90degree squat,85%1RM-120degree squat,90%1RM-90degree squat,90%1RM-120degree squat,95%1RM-90degree squat and95%1RM-120degree squat.The testing session was performed at Zhejiang Sport Technology College training center on every Tuesday and Thursday between10am to12pm. Participants were asked to perform squats with1repetition3sets using the assigned technique. The resting interval was1minutes and countermovement jumps were tested at right after the squat,3minutes later,6minutes later,9minutes later,12minutes later and15minutes later respectively.Results shown that the CMJ performance were significantly improved after85%1RM-90degree squat,90%1RM-90degree squat,90%1RM-120degree squat,95%1RM-90degree squat and95%1RM-120degree squat(P<0.05). There were no significant difference between85%1RM、90%1RM and95%1RM intensity level. Different squat, depth, the knee angel, also does not have significant difference.6and9minutes resting seems to be the most effective resting interval for participants in this study after85%1RM-90degree squat,90%1RM-90degree squat,90%1RM-120degree squat,95%1RM-90degree squat,85%1RM-90degree squat,90%1RM-90degree squat,90%1RM-120degree squat,95%1RM-90degree squat,95%1RM-120degree. For95%1RM-120degree9and12minutes resting seems optimum.