**3. Results**

No significant differences were observed for the different sleep parameters (PSQI, ISI, and ESS) between the U14 and U17 players (Table 2).

**Table 2.** Comparison of the means of sleep quality, sleepiness, and insomnia between the two groups.


Values are mean ± SD; PSQI: Pittsburgh Sleep Quality Index; ISI: Insomnia Severity Index; ESS: Epworth Sleepiness Scale.

The prevalence of players with poor sleep quality (PSQI ≥ 5) was 61.1% for the U14 group and 63.8% for the U17 group of older participants; mild insomnia (ISI ≥ 11) was 8.3% for the U14 group and 8.4% for the U17 group; sleep debt (ESS > 8) was 19.4% for the U14 group and 22.3% for the second group (see Table 3).



PSQI ≥ 5: poor sleep quality; ISI ≥ 11: mild insomnia; ESS > 8: sleep debt or excessive daytime sleepiness.

Although it was not significant, the balance performance with eyes open and closed for the U14 group was better (0.59 and 0.31, respectively).

In the between-group comparison, the agility values were higher (*p* < 0.01) in favor of the U14 group compared to the U17 group. Therefore, we reject the null hypothesis of equality of variances, and a significant difference between the two groups regarding agility performances was noted. Concerning the vertical (SJ) and horizontal (SBJ) jump tests, no significant difference was noted (*p* = 0.06 and *p* = 0.43, respectively).

Although the difference was not significant (0.06 > 0.05), the performance of the five-jump test (FJT) of the younger U14 players was better than that of the others, with a difference of 2% between the two groups.

On the other hand, the mean performance of the maximum aerobic speed capacity of the older U17 players was significantly higher compared to theU14 players (*p* < 0.05) (see Table 4).

**Table 4.** Performance parameters of balance, agility, strength, and MAS in the two groups.


Values are mean ± SD; OEB: open-eye balance; CEB: closed-eye balance; SJ: squat jump; SBJ: squat broad jump; FJT: five jump test; *t*-Test: Agility *t*-Test; VAMEVAL: maximum aerobic capacity test. Significantly different from U14: \* *p* < 0.05, \*\* *p* < 0.01.
