## 4 Discussion
Strength improvement positively affects the rate of force development, which is particularly crucial for fast movements such as jumping [46,47]. It has been observed that vertical jump height can be explained by knee extensor and flexor strength by approximately 30% [36]. Thus, deficiencies in strength could affect jumping performance. In one of the earliest studies on this subject [29], researchers investigated the relationship between bilateral asymmetry in isokinetic knee strength and the single-leg jump. The results indicated that the asymmetry index at 180\({}^{\circ}\)/s of isokinetic strength was positively correlated with the bilateral asymmetry index for the maximum flexion angle and the mean knee joint torque during single-leg jumps. In the present study, as previously mentioned, a positive correlation was observed between the asymmetry in the SLCMJ and the asymmetry in the isokinetic strength of the quadriceps at 60\({}^{\circ}\)/s, and a moderate negative correlation was found between the asymmetry in the SLCMJ and the asymmetry in the isokinetic strength of the hamstrings at 60\({}^{\circ}\)/s. More recent studies also report correlations between asymmetry indices in different tests [30], though these correlations were characterized as \"poor\" in some cases. This may be due to the use of an isometric strength test, as opposed to the current study, which utilized isokinetic strength assessment across the full range of motion of the joint at three different angular velocities. The literature includes studies that found no correlations between the asymmetry indices used. For example, [PERSON] et al. (2018) [48] studied whether asymmetries in isokinetic strength (60\({}^{\circ}\)/s and 300\({}^{\circ}\)/s) were related to asymmetries in jump tests (squat jump, CMJ). Their results showed no correlations except for one between squat jump asymmetry and knee flexion at 60\({}^{\circ}\)/s. In a later study [39], asymmetry indices derived from the Abalakov test, a change of direction test, and an iso-inertial power test were found to be unrelated. A lack of correlations between asymmetry indices was also reported in another study [38]. The limited correlations observed suggest that multiple and varied tests are needed to detect asymmetries in football players. Furthermore, since the above studies involved both genders and participants of different ages and skill levels, it appears that the lack of relationship between asymmetry indices across different tests is more related to the nature of the parameter being assessed and less to the characteristics of the sample [39]. As mentioned earlier, the results of the regression analysis in this study showed that the quadriceps and hamstring asymmetry indices could explain 20.6% of the variance in the CMJ Bilateral Asymmetry Index. In this case, an R-squared value of 20.6% suggests that approximately 20.6% of the variation in the dependent variable (SLCMJ asymmetry) can be explained by the independent variables included in the model, while the remaining 79.4% may be attributed to factors not captured by the model or random variation. Although this is not a very high proportion, it can still provide useful insights depending on the context and domain of the analysis. This study has certain limitations. The participants were only male athletes in the developmental age group, meaning the results cannot be generalized to both genders or to different skill levels. The effect of biological maturation on the asymmetry indices has not been examined. Additionally, to detect asymmetry in the SLCMJ, equipment that calculates jump height based on flight time was used. The use of a force plate would provide more detailed and accurate data. Furthermore, only isokinetic strength assessments of the knee flexors and extensors were conducted.