Risk Factors for Injury Among Japanese Collegiate Players of American Football Based on Performance Test Results.

Iguchi, J, Watanabe, Y, Kimura, M, Fujisawa, Y, Hojo, T, Yuasa, Y, Higashi, S, and Kuzuhara, K. Risk factors for injury among Japanese collegiate players of American football based on performance test results. J Strength Cond Res 30(12): 3405-3411, 2016-The purpose of this study was to identify how risk factors for injury during American football are related to players' physical strength as determined using typical performance tests. One hundred 53 Japanese collegiate players of American football were recruited for this study. Eight potential risk factors were evaluated: position (skill vs. lineman), body mass index, back squat one-repetition maximum, vertical jump height, power, height, body weight, and previous injury. Using multivariate Cox regression, we examined how these factors were associated with knee sprain, ankle sprain, and hamstring strain. We recorded 63 injuries (17 knee sprains, 23 ankle sprains, and 23 hamstring strains). Players with higher power were at significantly greater risk for knee sprains (p = 0.04), those with low power had a significantly higher incidence of ankle sprain (p = 0.01), and vertical jump height was a significant predictor of hamstring strain (p = 0.02). We identified several independent predictors of injuries associated with American football. Our findings may contribute to the development of effective screening tests and prevention exercises.