This study aimed to evaluate the post-activation potentiation (PAP) effects of an eccentric overload (EOL) exercise on vertical and horizontal jumps and change of direction (COD) performance. Twelve healthy physically active male subjects were involved in a cross-over study. The subjects performed 3 sets of 6 repetitions of EOL half-squats for maximal power
using a flywheel ergometer. PAP using an EOL exercise was compared between a medium (M12 EOL) vs. high inertia (H-EOL) experimental condition. Long jump (LJ) was recorded at 30 s, 3 min, and 6 min following both EOL exercises and compared with baseline values (control). The same procedure was utilised to assess countermovement jump (CMJ) height and peak power and 5-m change of direction test (COD-5m). A fully Bayesian statistical approach to provide probabilistic statements was used in this study. LJ performance reported improvements following M-EOL and H-EOL exercise (Bayes factor [BF10]=32.7, strong; BF10=9.2,moderate), respectively. CMJ height (BF10=135.6, extreme; BF10>200, extreme), CMJ peak power (BF10>200, extreme; BF10=56.1, very strong), and COD-5m (BF10=55.7, very strong; BF10=16.4, strong) reported improvements following M-EOL and H-EOL exercise, respectively. Between analysis did not report meaningful differences in performance between M-EOL and H-EOL exercises. The present outcomes highlight that PAP using an EOL (M23 EOL and H-EOL) improves LJ, CMJ height, CMJ peak power, and COD-5m in male athletes. The optimal time window for the PAP effect was found for both EOL conditions from 3 to 6 min. However, M-EOL and H-EOL produce similar PAP effect on LJ, CMJ and COD-5m tasks.