The aim of this study was to examine the acute effect of flywheel training on countermovement jump performance in elite youth male basketball players, by measuring jump height at the 1-minute, 3-minute and 5-minute post-training. Fifteen young, healthy, elite male athletes (age: 17.0 ± 1.0 years; height: 193.1 ± 7.3 cm; body mass: 83.6 ± 8.2 kg; BMI: 22.4 ± 1.7 kg/m²) participated in the study. The participants were randomly assigned to two groups, performing the experimental (PAPE) and control protocol in a crossover design. Both protocols included standardized warm-up and countermovement jumping, while the experimental protocol additionally involved flywheel training between the warm-up and jumping. The flywheel training consisted of the half-squat exercise in three sets of six maximal repetitions, with a flywheel inertia of 0.025 kg·m². The results showed no statistically significant differences in countermovement jump height at 1-minute, 3-minute and 5-minute post-intervention time points (p > .05). Such an outcome was expected at the first time point, due to the well-known dominance of fatigue over potentiation in the initial minutes following an activation exercise. However, the results obtained at the second and third time points were not consistent with previous findings. The absence of acute improvements is most likely attributable to the participants’ age, which contributes to increased susceptibility to central fatigue. Further research is needed to determine whether this type of training can acutely enhance countermovement jump height in young athletes.