Effect of volume on eccentric overload-induced postactivation potentiation of jumps

Purpose
To investigate the post-activation potentiation (PAP) effects of different eccentric overload (EOL) exercise volumes on countermovement jump (CMJ) and standing long jump (LJ) performance.

Methods
Thirteen male university soccer players participated in a cross over design study following a familiarization period. Control (no PAP) CMJ and LJ performances were recorded, and three experimental protocols were performed in a randomized order: 1, 2 or 3 sets of 6 repetitions of flywheel EOL half-squats (inertia=0.029 kg·m²). Performance of CMJ and LJ
were measured at 3 and 6 min following all experimental conditions. The time course and magnitude of the PAP were compared between conditions.

Results
Meaningful positive PAP effects were reported for CMJ after 2 (Bayes factor
[BF₁₀]=3.15, moderate) and 3 (BF₁₀=3.25, moderate) sets but not 1 set (BF₁₀=2.10, anecdotal). Meaningful positive PAP effects were reported for LJ after 2 (BF₁₀=3.05, moderate) and 3 (BF₁₀=3.44, moderate) sets but not 1 set (BF₁₀=0.53, anecdotal). Two and three set protocols resulted in meaningful positive PAP effects on both CMJ and LJ after 6 but not 3 min.

Conclusion
This study reported beneficial effects of multiple-set eccentric overload exercise over a single set. A minimum of two sets of flywheel EOL half-squats are required to induce PAP effects on CMJ and LJ performance of male university soccer players. Rest intervals of around 6 min (greater than 3 min) are required to maximize the PAP effects via multiple sets of EOL exercise. However, further research is needed to clarify the optimal EOL protocol
configurations for PAP response.