## 3 Results
### Countermovement Jump Performance  
Figure 5 presents the effects of a five-week AEL training program on countermovement jump height, propulsive impulse, peak power, and relative peak power in the AEL, CMJ, and CON groups. For jump height, significant effects of group (F\({}_{2,27}\) = 4.31; \(p\) = 0.02; \(\eta^{2}\)p = 0.24) and time (F\({}_{1,27}\) = 13.42; \(p\) < 0.01; \(\eta^{2}\)p = 0.33) were found, both representing large effects. Additionally, a large group \(\times\) time interaction was observed (F\({}_{2,27}\) = 74.20; \(p\) < 0.01; \(\eta^{2}\)p = 0.01; \(\eta^{2}\)p = 0.85), indicating that the magnitude of change varied meaningfully across groups. Post-intervention comparisons revealed significantly greater jump height in the AEL group compared to CON (\(p\) < 0.001; d = 1.50, large effect) and in the CMJ group compared to CON (\(p\) = 0.003; d = 1.00, moderate effect). Both AEL (\(p\) < 0.001; 95% Cl\({}_{\rm dif}\): 4.081 to 6.059 cm) and CMJ (\(p\) = 0.017; 95% Cl\({}_{\rm dif}\): 0.231 to 2.209 cm) groups improved significantly, whereas the CON group decreased in jump height (\(p\) < 0.001; 95% Cl\({}_{\rm dif}\): -4.219 to -2.241 cm). For peak power, a significant group effect was found (F\({}_{2,27}\) = 4.83; \(p\) = 0.01; \(\eta^{2}\)p = 0.26, large), while no significant main effect of time was observed (F\({}_{1,27}\) = 2.57; \(p\) = 0.12; \(\eta^{2}\)p = 0.09, medium). However, a large group \(\times\) time interaction was present (F\({}_{2,27}\) = 76.71; \(p\) < 0.001; \(\eta^{2}\)p = 0.85). Post-intervention comparisons showed significant differences between AEL and CON (\(p\) = 0.002; d = 0.59, small effect) and between CMJ and CON (\(p\) = 0.006; d = 0.43, small effect). The AEL group improved significantly (\(p\) < 0.001; 95% Cl\({}_{\rm dif}\): 180.1 to 279.7 W), while no significant change was observed in the CMJ group (\(p\) = 0.195; 95% Cl\({}_{\rm dif}\): -17.60 to 81.96 W). The CON group showed a significant decrease (\(p\) < 0.001; 95% Cl\({}_{\rm dif}\): -244.5 to -145.0 W). Regarding relative peak power, no significant group effect was found (F\({}_{2,27}\) = 2.91; \(p\) = 0.07; \(\eta^{2}\)p = 0.18, large), nor a time effect (F\({}_{1,27}\) = 1.66; \(p\) = 0.208; \(\eta^{2}\)p = 0.06, medium), but a large interaction was present (F\({}_{2,27}\) = 62.62; \(p\) < 0.001; \(\eta^{2}\)p = 0.82). Significant post-intervention differences were observed between AEL and CON (\(p\) = 0.01; d = 0.73, moderate effect), and CMJ and CON (\(p\) = 0.03; d = 0.36, small effect). The AEL group showed significant improvements (\(p\) < 0.001; 95% Cl\({}_{\rm dif}\): 2.317 to 3.823 W/kg), while the CMJ group showed no significant change (\(p\) = 0.202; 95% Cl\({}_{\rm dif}\): -0.273 to 1.233 W/kg). The CON group declined significantly (\(p\) < 0.001; 95% Cl\({}_{\rm dif}\): -3.483 to -1.977 W/kg). Finally, for propulsive impulse, a significant group effect (F\({}_{2,27}\) = 3.56; \(p\) = 0.04; \(\eta^{2}\)p = 0.21), time effect (F\({}_{1,27}\) = 8.65; \(p\) = 0.006; \(\eta^{2}\)p = 0.24), and group \(\times\) time interaction (F\({}_{2,27}\) = 41.47; \(p\) < 0.001; \(\eta^{2}\)p = 0.75) were observed--all large effects. Post hoc comparisons showed significant differences between AEL and CON (\(p\) = 0.002; d = 0.71, moderate effect). The AEL group improved significantly (\(p\) < 0.001; 95% Cl\({}_{\rm dif}\): 12.47 to 20.15 N\(\cdot\)s), the CMJ group showed no change (\(p\) = 0.754; 95%  
Figure 6 presents the Rs and NRs boxers to the AEL training program for jump height, propulsive impulse, peak power, and relative peak power of the CMJ in the AEL, CMJ, and CON groups. For jump height, the AEL group exhibited a large improvement (15.1%; d = 1.00) with a responder rate of 90% (9 out of 9). The CMJ group showed a small increase (3.3%; d = 0.24) with three responders (30%), while the CON group demonstrated a large decrease (\(-\)9.7%; d = \(-\)1.10) and no responders. Regarding propulsive impulse, the AEL group achieved a small but meaningful increase (8.7%; d = 0.50) with 90% responders.