2023 Volume 31 Issue 1 Pages 24-30
This study analyzed how long-term exercise suspension due to COVID-19 affected the occurrence of injuries in official post-suspension Japanese collegiate American football games in 2020. Injury report data submitted by Kantoh Collegiate Football Association were analyzed and compared between A (2020) and B (1991-2010, 20years). We analyzed the number of cases of injury per match, trauma classification, trauma by body part, and trauma name. The injury incidence rate was A: 2.34 and B: 1.33 cases/match; trauma classification included bruises/contusions (A: 32.4%, B: 16.7%) and fractures (A: 9.0%, B: 2.4%); body parts included the lower leg (A: 14.5%,B: 7.8%) and thigh (A: 9.0%, B: 4.9%); and trauma diagnosis included lower-leg muscle spasm (A: 8.3%, B: 2.9%) and thigh bruises (including muscle pulls) (A: 8.3%, B: 4.0%). All were significantly higher in A (p＜0.05). We considered these factors to be due to decreased lower-limb joint flexibility caused by long-term inactivity and excessive load on muscles and tendons of the lower legs and thighs due to movements such as dashing, stopping, cutting, and turning. One cause of the increase in fractures may be the inability to avoid injury due to decreased bone strength or decreased skill due to inadequate actual practice.
