Effects of a newly designed daily exercise program in reducing the number of injuries in young football (soccer) players

Daily exercise-based injury prevention program (IPP). The IPP consists in one session a day for five days a week (training days), to be performed either at home (unsupervised) or in the football academy gym (before football training) under medical staff supervision, with none or minimal equipment required. When players performed the IPP in the academy gym, they were supervised in groups of 5-15 players, depending on the number of players attending football training session on that day. Each session was designed to last 10 minutes and consists of a circuit of four exercises repeated for two sets, with a 1-minute rest in between. Each exercise includes three variations (LEVEL 1-3) to ensure a progression to meet the physical characteristics of the different age groups and of each player. For example, in order to increase hip adductors muscle strength, players progressed from side-lying hip adduction exercise (LEVEL 1) to ball squeeze (LEVEL 2) and Copenhagen exercise (LEVEL 3), whereas double leg calf raise (LEVEL 1), single leg calf raise (LEVEL 2) and single leg calf raise on step (LEVEL 3) were prescribed to improve calf muscle strength. Players from under 9 (U9) to U11 started performing the LEVEL 1, while players from U12 to U15 and from U16 to U18 began with LEVEL 2 and 3, respectively. They gradually progressed at their own pace, and when they perceived the exercise as too easy, they increased the number of repetitions and then move on to the next level. However, when they perceived the level as being too difficult, they could execute the easier level. Players had to perceive the exercise as a "hard intensity" exercise, but no specific objective scale was used to measure the exercise intensity perceived. The IPP was performed over a 6-month period, and the participants were reviewed on a weekly basis during the IPP execution, to evaluate if they needed to move up or down a level. The rationale behind this approach was to implement an IPP consisting of different sessions short in duration, easy to perform, and without need of costly equipment and/or space, to encourage the players’ adherence while targeting risk factors for the most common injuries in youth football. All players, their parents and/or guardians, and the medical staff were informed about the IPP design, and they were provided with a document showing the IPP exercises and describing how to perform them. Moreover, theoretical and practical training sessions were given to physiotherapists to ensure a high quality supervision and the players were instructed on how to perform the IPP correctly. The players' adherence to the IPP was not evaluated.