Association of Sports Participation and Training Frequency with Injury in Japanese Students Majoring in Physical Education: A Retrospective Analysis

Objectives: This study evaluated prior sports participation and training frequency during elementary to high school and their association with acute and overuse injuries in Japanese college students currently majoring in physical education.Methods: This retrospective study included 292 students who completed questionnaires that assessed their type of sport participation (single sport or multiple sports), training frequency (number of days per week), and injury history (acute and overuse) during the elementary, junior high, and high school periods.Results: In total, 47.9% (95% confidence interval [CI]: 38.2–57.7) of elementary school-aged athletes played multiple sports; this decreased to 22.3% (95% CI: 14.1–30.4) in junior high school and 5.5% (95% CI: 1.0–9.9) in high school. There was a significant difference in the training frequency between those who had overuse injuries and not in elementary (p < 0.05), and junior high school (p < 0.05).Conclusions: The results of this study suggest that participating in multiple sports through junior high school may lead to improved sports levels (i.e., participation in higher levels of competition). In addition, appropriate management of training frequency may help reduce the incidence of overuse injuries.