## 2 Materials and Methods
### Muscle-Strength Testing  
After completing the questionnaire, isometric tests for quadriceps, hamstring, and abductor muscles were performed using an HHD (MicroFET 2; Hoggan Scientific, Salt Lake City, UT, USA). The same examiner performed all strength tests. A previous systematic review [31] indicated that HHD has moderate to good reliability and validity compared with the \"gold standard\" isokinetic dynamometer. Participants, after a warm-up including  
\begin{table}
\begin{tabular}{c c} \hline \hline  & **Mean**\(\pm\) **SD** \\ \hline Weight (kg) & 74.21 \(\pm\) 7.90 \\ Height (m) & 1.79 \(\pm\) 0.06 \\ BMI (kg/m\({}^{2}\)) & 23.19 \(\pm\) 1.80 \\ Starting Training Age (years) & 7.77 \(\pm\) 3.03 \\ Competitive playing experience years & 4.00 \(\pm\) 4.31 \\ Training hours/day & 2.31 \(\pm\) 0.63 \\ Training days/week & 5.64 \(\pm\) 1.06 \\ Games played the previous year & 19.33 \(\pm\) 9.92 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Participants’ demographic characteristics.  
Figure 1: Data collection process.  
two trials of approximately 2 s of submaximal contraction, performed three maximal 5 s contractions, separated by a rest of at least 20 s. All tests were recorded in Newton, and the higher value was used for the calculation of the Limb Symmetry Index.  
To assess knee extension strength, participants were seated on a specific metal table with the back straight, and both hip and knee angle at 90\({}^{\circ}\) of flexion. The participants kept their hands crossed on their chest. A physical therapist stabilized the thighs with his hands directly above the hip joint to prevent thigh movements during maximal quadriceps isometric contraction. A belt placed just proximally to the medial malleolus across a rigid frame on the back of the tibia, stabilized the HHD on this. Participants were asked to try to extend their tibia as forcefully as possible for five seconds. [PERSON] et al. [32] report that this testing configuration is a valid and reliable option for knee extensor strength testing.  
To assess isometric hamstring strength, participants were placed in a prone position with their feet off the bed. The examiner passively flexed the knee at a height equal to the athlete's foot length [21; 33]. This position is approximately 30\({}^{\circ}\) of knee flexion. Then, the examiner placed the dynamometer on the heel and asked the athlete to contract their hamstrings maximally by flexing their knee as forcefully as possible for 5 s. This is an often-mentioned technique in the literature in order to assess hamstring strength using HHD [33; 34]. [PERSON] et al. [21], using HHD, reported an excellent inter-rater reliability (ICC = 0.96 for quadriceps and ICC = 0.91 for hamstrings) and a moderate-to-good correlation with isokinetic assessment.  
Hip inductor strength was also measured to add information regarding the pelvis-stabilizing function, according to the protocol by [PERSON] et al. [35], who reported high-to-excellent reliability (ICC = 0.76-0.98). The athletes were in a side-lying position, with the testing hip on the upside in a neutral position. The opposite leg was flexed in the hip and knee at approximately 90 degrees. The participants stabilized themselves by holding the examination table with their hands. The examiner stood behind them, one hand stabilizing the pelvis while the other hand held the HHD 5 cm proximal to the lateral malleolus. Then, the participants pushed maximally against the dynamometer for 5 s.