Injuries in a Japanese Division I collegiate american football team: a 3-season prospective study.

Context: Previous research on American football injuries in Japan has focused on incidence proportion in terms of the number of injuries divided by the number of players. This is the first study to examine injury rates over several seasons.
Objective: To conduct a prospective study of injuries in a Japanese Division I collegiate American football team over the 2007 through 2009 seasons.
Design: Cohort study.
Setting: Collegiate football team at Doshisha University, Kyoto, Japan.
Patients or Other Participants: All 289 athletes who played on the collegiate Division I football team during the 2007 through 2009 seasons.
Main Outcome Measure(s): A certified athletic trainer kept a daily record of all practice and game injuries. Injury rates were calculated according to season, injury type, body part, severity, and mechanism. Injuries were also analyzed according to position of player, school year, and playing experience.
Results: The game injury rate (GIR; 32.7 injuries/1000 athlete-exposures) was higher than the practice injury rate (PIR; 10.9 injuries/1000 athlete-exposures) over the 3 seasons (P < .05). The PIR was higher among Japanese players than the comparable United States collegiate football injury rates (5.8-7.0 injuries/1000 athlete-exposures). Ankle and foot injuries occurred more frequently during games, whereas thigh and gluteal injuries occurred more frequently during practices.
Conclusions: Our data show differences between games and practices in terms of injury rates, body parts injured, and positions of players injured. The high PIR in Japan may be due to the increased contact during practices and length of practices compared with the United States. Further research involving multiple teams is recommended to validate the trends noted in this study. The expanded data set could assist in the development of safety regulations and preventive interventions for Japanese football.