Optimal recovery time for post-activation potentiation following a ballistic concentric only half squat in elite youth rugby players

The purpose of this study was to determine the optimal rest interval which produces the greatest postactivation potentiation (PAP) response during a squat jump (SJ) following a ballistic concentric only half squat (COHS). Twenty-four elite youth rugby players (18.4 ± 0.32 y, 181.4 ± 2.25 cm, 90.0 ± 12.36 kg) visited the weight room on four separate occasions. During each potentiation session subjects performed a baseline SJ followed by 1 set of 2 repetitions of either a COHS or a half squat protocol at 90% of their 1RM or a control protocol followed by subsequent SJs at five rest intervals. These rest intervals were ~15 s, 2, 4, 6 and 8 minutes post the conditioning activity. Jump height (JH), peak force (PF), peak power (PP) and RFD were all measured during the SJs. A repeated measures ANOVA revealed there was no effect of rest interval on JH, PP, PF or RFD. There was a condition effect on PF, PP and RFD where the COHS and half squat conditions produced a greater amount of PF and PP compared to the control condition and the COHS produced a greater amount of RFD compared to the other two conditions. The optimal rest interval could not be identified as the length of the rest interval had no effect on the PAP response and the COHS was the most effective conditioning activity. Consequently, it was recommended that subjects self-select a rest interval up to 8 minutes between the COHS and the SJ.