Background FIFA 11+ program has been shown to reduce the risk of injury in football players, but it has not been evaluated in adolescent Japanese players.

Objective To investigate the effects of FIFA 11+on the risk of injury in adolescent Japanese football players.

Design Cohort study.

Setting Six male and 4 female Japanese Under-18 (age: 16–18 yr.) and Under-15 (age: 13–15 yr.) football teams were followed for six seasons (from 2010 to 2015). The 2010 season was considered as the control season, with the players practicing their usual warm-up techniques. Throughout the seasons from 2011 to 2015, the players exclusively performed FIFA 11+; these 5 seasons were considered the intervention seasons.

Participants A total of 2,344 athletes (1,815 male, 529 female; age: 12–18 yr.).

Interventions FIFA 11+program was conducted at least twice per week, throughout the intervention seasons.

Main Outcome Measurements For each of the three categories: football [matches+trainings], matches, and trainings, the injury rates were reported as the number of injuries per 1000 player-hours (1000PH).

Results In males, the injury rate during football, the matches, and the trainings were 4.0, 8.9, and 3.4 in the control season, and 2.4, 6.9, and 1.8 in intervention seasons (mean values from 2011 to 2015), respectively. In females, the injury rates during football, the matches, and the trainings were 2.7, 2.2, and 7.5 in the control season, and 3.1, 2.6, and 8.9 in intervention seasons (mean values from 2011 to 2015).The injury rates were reduced significantly in the intervention seasons, compared with the control season in males, but not in females. Non-contact injuries were significantly reduced in both genders.

Conclusions FIFA 11+program reduced the risk of injury in adolescent Japanese male football players, and reduced non-contact injuries in adolescent Japanese female football players.