## 2 Materials and Methods
### Experimental Procedure  
A standard warm-up routine was performed prior to the study, including light aerobic warm-up and dynamic stretching exercises. The participants then attended a familiarization session where the testing conditions were explained and trial sets were carried out. Firstly, participants performed reaction time tests using the FiTRO Reaction Check(FiTRONiC, Bratislava, Slovakia) and Witty SEM (Microgate, Bolzano, Italy) diagnostic systems. Secondly, jumping was measured by the OptoGait (Microgate, Bolzano, Italy) system and sprint tests, change of direction speed tests, and reactive agility tests were measured by the Witty SEM (Microgate, Bolzano, Italy) system. Y-shaped agility testing has previously been found to be reliable and valid [8]. A Witty light-based timing system was used to record times and set reactive conditions. The gates were set at a width of 1.5 m and a height of 1.2 m. A goniometer was used to determine the 45\({}^{\circ}\) angle of the change of direction. The test consisted of a 5-m-long sprint, a 45\({}^{\circ}\) change in direction to the left or right, and finally a 5-m-long sprint to the finish gate. The timing system dictated the direction in which participants proceeded after having completed the first 5 m of the course. The photocell of the timing system presented an arrow denoting a change in direction to the right or left with an approximate 40 to 45 ms delay after passing by the starting gate. Trials were performed in triplicate and the best times were used for analysis. Reactive Agility Test (RAT)  
The reactive agility test that was used was a modified version of the stop-and-go reactive agility test developed by [PERSON] et al. [10]. In this test, four photocells were placed 2 m from the starting point in a semi-circular arrangement. The task for the participant was to run to the lit photocell as fast as possible, wave at this photocell, and then run back to the starting point. The test consisted of 20 visual reactions (five in each direction) with a generation time of 1 s. A green light was used as a stimulus, while the other photocells remained off. The result of the test was a total time for one trial. Simple and Choice Reaction Time Test  
The FiTRO Reaction Check diagnostic system consists of two switches connected by means of an interface to a computer. Special software measured the time between the stimulus appearing and the participant's response. Participants were required to respond to either one visual stimulus (a simple reaction time test) or two visual stimuli in the form of a circle and cross (a two-choice reaction time test) positioned on switches on a table. The switches had to be pressed in accordance with the stimulus on the screen. Participants had to press the right-most switch when a green circle appeared and the left-most switch when a red cross appeared. Participants performed 2 trials of 20 responses in each test. The data from the best trials of simple reaction time and 2-choice reaction time testing were selected for analysis. Reaction Time Test to Fast Generating Visual Stimuli  
The Witty SEM diagnostic system used in this study included four photocells which were situated in-line on a table with a distance of 10 cm between them. Participants were required to react as fast as possible with their dominant hand to photocells which lit up green. Both tests consisted of 20 visual reactions, i.e., 4 for each photocell. In this test, the visual stimuli were generated immediately after each response. The final result was the best total reaction time after two trials. Squat Jump (SJ)  
A squat jump is a jump without previous countermovement that starts from a 90\({}^{\circ}\) knee position (measured by a goniometer) with the hands on the hips. Participants were instructed to jump as high as possible from a semi-squatting position without countermovement. The final result of the test was the highest jump of two trials.