## 5 Discussion
Contrary to these findings, in female players, no correlations have been identified between BF% and performance-related variables, as well as no differences were found between BF% groups. Regarding the relationship between FFM and jumping ability, our study did not confirm any significant correlations between FFM and jump height and relative power in male players. On the contrary, in female players, FFM and BM were negatively correlated with both jump height and relative power. There were significant differences between FFM groups in CMJ-S height and relative power. HFFM female players jumped significantly lower and demonstrated less relative power than the LFFM and RFFM female players. To understand these results, we need to consider other factors, such as the age and height of the athletes and their years of experience. The FFM male groups did not show differences in fat mass, but the athletes who had the highest FFM values were also the tallest and, at the same time, the youngest (decimal age). Probably, these athletes had fewer years of basketball training and were less efficient in their jumping skills, compared to the other FFM groups' players. This detail can weigh on the result of their specific performance, nullifying the difference between groups. On the other hand, female athletes did not show differences in height between FFM groups, but showed %BF and age differences, with the youngest players exhibiting more than 11 kg of FFM. The explanation for the female results did not seem to be the same when the groups were compared. Besides, the LFFM group presented less FFM than the HFFM one and were older than the other players, which could mean more experienced in the structured activities of basketball training, and as it was noted for boys, this can be reflected in a better mastery of the jumping technique. However, RFFM players had less FFM and %BF than HFFM players. As %BF was not a differentiating variable of the young female performance, we would say that probably the fewer years of experience, but also the large increase in FFM of these athletes, may not be of great help for the specific jumping performance. It is interesting to note that, in both sexes, the increase in FFM (above a certain value) ceases to be functional for athletes' jumping ability, as well as for speed and COD ability. According to the literature, it seems that BC influences the speed and COD ability [25], which are considered crucial attributes for basketball performance in both adults [7; 40] and youth teams [12; 31]. A previous study with young basketball players found that U-12 overweight players had worse performance in running (sprint and endurance) than their leaner counterparts [25]. Although in this study, conducted with male players, no significant correlation was observed between FFM and speed and COD tests, there were significant differences in sprint and COD between FFM groups (see ANCOVA results in Table 4). The results of the 20 m speed test showed that HFFM players were 0.14 s slower than RFFM and LFFM players. The T-test results highlighted the same tendency--the HFFM players were significantly slower than RFFM (+0.55 s) and LFFM (+0.52 s) players. On the contrary, in female players, there was no correlation between FFM and the speed test, but a small positive correlation has been observed between FFM and the T-test. Despite this, no significant differences were found between FFM groups in the T-test results, although HFFM female players were 0.13 and 0.16 s slower than LFFM and RFFM players, respectively. In the present study, body mass and FFM were positively correlated with SUM HG and MBT, in both sexes. Supposedly, players with more muscle mass have more handgrip strength, and therefore, they can throw the medicine ball further. Previous studies with young Portuguese soccer players showed a positive correlation between FFM and upper body strength [41; 42]. It is worth mentioning that the only performance-related variable correlated with FFM was the number of rebounds per game in male players.