## 2 Materials and Methods
### Design  
One week prior to the initial assessment, CG and FG were familiarised with the different tests and technologies. Subsequently, initial or baseline (pre) assessments were conducted under conditions like those of the familiarisation tests in both groups. Subsequently, the final (post) assessments took place 12 weeks after the pre-assessments. The assessments took place in the evening, between 17:00 and 20:00 for each measurement. They were conducted at the same time using the same order and conditions as the first assessment. Body composition, manual dynamometry, countermovement jump (CMJ), and cardiorespiratory fitness were evaluated at the pre- and post-assessments.  
Bone mass (BMC in g, and BMD in g/cm\({}^{2}\)), fat mass (g and %), and fat free mass (g) were calculated using a dual X-ray densitometry (Hologic Series Discovery QDR, Software Physician's Viewer, APEX System Software Version 3.1.2. Bedford, MA, USA). The bone densitometer was calibrated before each day of testing using a lumbar spine phantom and following the guidelines set by the manufacturer. Participants were evaluated lying down with limbs extended, within scanner limits. The same operator performed all tests for consistency. The explosive force was evaluated by the CMJ. Each subject performed 3 jumps with 1 min rest between each jump, considering the flight time in centimeters. The highest flight time among the 3 jumps was taken for the result. The flight time (s) was measured using an optical data collection system (Optojump; Optojump Next v. 1.12.1.0; Bolzano, Italy). Upper body muscle strength (kg) was evaluated using an electronic dynamometer (Camry Mod: EH101, Valencia, Spain). Each subject made 3 attempts with 1 min rest in between, all with their dominant hand. The highest kg value of the 3 attempts was chosen as the result. VO\({}_{2}\) max was estimated using the Course Navette Test, a progressive test measuring maximum oxygen uptake. The test was performed once for each measurement, obtaining the value of the period made by each subject. A formula was used to estimate the VO\({}_{2}\) max.  
FG was monitored using a GPS unit (15 Hz, Spi Pro X, GPSports, Canberra, NSW, Australia) attached to the player's torso [26]. GPS software (Team AMS R1 2019.1 software, GPSports, Canberra, NSW, Australia) provided total distance (TD), high-speed running (Z5: 13.1-17 km\(\cdot\)h\({}^{-1}\)), and sprinting information (Z6: \(\geq\)17.1 km\(\cdot\)h\({}^{-1}\)). Players participated in a 10 m sprint test to calculate speed zones [27]. Sprint time (s) (\(\geq\)17.1 km\(\cdot\)h\({}^{-1}\)) and distance (m) were recorded. The GPS also recorded peak acceleration peaks, number of accelerations, and high-intensity accelerations above 2.5 m/s\({}^{2}\). High-intensity accelerations (ACCMAX) were based on [PERSON] (2010) [28], defined as accelerations above 2.5 m/s\({}^{2}\). The average peak velocity of each acceleration (VMaxACC; km\(\cdot\)h\({}^{-1}\)), time between accelerations (IACC; s), distance covered and number of high-intensity accelerations (HI acceleration; n), and average distance covered in accelerations exceeding 2.5 m/s\({}^{2}\) (TDACC; m) were calculated for comparison of the results. All variables are calculated both in absolute terms to analyse each training and match of each player and in relative terms to determine the relative difference in the percentage of training load compared to match load.