## 2 Materials and Methods
### Procedures  
After presenting and explaining the procedures to the participants and consequently obtaining informed consent, characterization data were collected. Body weight was measured with an electronic scale (TANITA SC-330), with the participant wearing the least amount of clothing. For height measurement, shoes were removed before using a stadiometer. BMI was calculated by dividing body weight by the square of height [17]. Participants were also asked about some subjective indicators of well-being, namely the motivation for the proposed tasks, the quality of sleep the night before, the perception of fitness status and the perception of general well-being, through a scale from 0 (none) to 10 (maximum), to assess their physical and psychological availability [40]. Participants performed a 5 min low-intensity running warm-up exercise. After the warm-up, tests were administered to assess the characteristic football skills considered: vertical jump ability, balance and speed. The vertical jump was evaluated with the countermovement jump. Participants started from an upright position, with feet shoulder-width apart, legs fully extended, and hands on hips to eliminate upper limb movement [41; 42]; they were then asked to perform a quick semi-flexion of the hips and knees, followed by an explosive extension so that they immediately perform a maximum vertical jump [42]. Before the test participants were asked to perform several submaximal familiarization attempts. Jump height (cm) was recorded using the Optojump system (Microgate, Italy). Participants performed three trials with a 30 s recovery period between them. The mean value was used for subsequent analysis [12]. The Y balance test was used to assess balance, according to the protocol described by [PERSON] et al. [43]. Starting in a unipedal support stance and with hands placed on hips, the participants were asked to reach the contralateral leg as far as possible in the three test directions (anterior, posteromedial and posterolateral). Each participant performed six training attempts to minimize the influence of a learning effect. The test was performed in the following order: anterior with the right lower limb (in support), anterior with the left lower limb, posteromedial with the right lower limb, posterolateral with the right lower limb and posteromedial with the right lower limb, lateral with left lower limb [43]. Participants completed three successful testing attempts for each reaction direction, with each of the lower limbs being averaged (absolute reach distance in cm). Subsequently, the normalized reach distance was calculated, in %, for each direction and side (absolute reach distance/actual length of the lower limb \(\times\) 100) and, finally, the composite reach distance for each side, also in % (sum of the three normalized reach distances/three times the actual length of the lower limb \(\times\) 100), with the lower limb measured from the anterosuperior iliac spine (ASIS) to the medial malleolus. Attempts were discarded and repeated if the participant failed to maintain a unilateral stance, failed to maintain range foot contact with the range indicator in the target area while the indicator is in motion (kicking the range indicator to obtain a performance), using the reach indicator for support, or failed to return the reaching foot to the starting position. The 20 m sprint test was used to assess speed. The test was done on a tarmac floor, with two cone doors 20 m apart. Witty timing gates (Microgate, Italy) were used, and the participants always adopting the same posture: split posture, with one foot forward and one foot behind, with the starting line placed 0.3 m behind the first timing gate, as recommended by [PERSON] et al. [44]. Participants completed three trials, with 3 min of passive recovery between each trial [45], and the average time was considered. Flexibility assessment of the hip flexor and knee extensor muscles, as well as the knee flexor muscles, was done with the modified Thomas test and the sit-and-reach test, respectively.