Yiming Liu, Xinmao Zou, Lu Dong, Ning Xu, Mengqi Chen, Liming Zhu
Purpose: This study compared the acute time-course effects of a Multi-dimensional Elastic Band (MEB) activation protocol versus a traditional Heavy Barbell Squat (HBS) protocol on lower limb explosive performance, aiming to identify optimal recovery windows. Methods: Sixteen trained male athletes (age: 19 ± 0.9 yrs) participated in a randomized crossover study consisting of three sessions: Control, HBS (4 reps at 90% 1RM), and MEB (continuous vertical jumps against elastic resistance). Countermovement jump (CMJ) height and Peak Power Output (PPO) were measured at 3, 6, 9, 12, 15, and 18 minutes post-activation. Results: pairwise comparisons did not reach statistical significance (p > 0.05), while effect size analysis (HBS and MEB vs. Control at each time point) indicated practical improvements. The MEB protocol induced a rapid potentiation response, demonstrating moderate effect sizes in CMJ height and PPO as early as 3 minutes post-activation. In contrast, the HBS protocol exhibited delayed potentiation, with improvements appearing only after 9 minutes, likely due to residual fatigue. Conclusion: Multi-dimensional elastic resistance is a time-efficient alternative for inducing Post-activation Performance Enhancement (PAPE), offering a rapid onset of practical potentiation (within 3 min) based on effect size analysis. These findings suggest MEB is particularly suitable for pre-competition warm-ups where recovery time is severely constrained.