The Effects of Accentuated Eccentric Loading on the Drop Jump Exercise and the Subsequent Postactivation Potentiation Response.

The aims of this study were to (A) investigate the acute effects of different drop jump (DJ) accentuated eccentric loading (AEL) protocols and (B) to investigate the effect of these AEL DJ protocols on subsequent countermovement jump (CMJ) performance. The subjects were 12 strength-trained athletes, initially, baseline CMJ performance was assessed and individual optimal DJ drop height identified. In subsequent weeks subjects completed 1 set of 5 DJ's with no additional load or an AEL of 10, 20 or 30% of their individual body mass (BM) utilising dumbbells to provide the extra load. After the AEL DJ protocols 3 CMJ's were completed after 2, 6 and 12 minutes rest. A generalised linear mixed model was used to investigate the effects of AEL load and time post DJ's on CMJ height, peak power and GRF. The 20% AEL condition resulted in greater CMJ height in comparison to all other conditions (p < 0.001). CMJ height was significantly greater after 2 and 6 minutes rest compared to 12 minutes (p < 0.001 and p < 0.05 respectively). Greater peak power was also found during the CMJ's after the 20% AEL condition compared to baseline, BM and 10% AEL (p < 0.05). In conclusion 5 DJ's with 20% AEL followed by a 2 minute recovery period resulted in significant enhancement in CMJ height and peak power.