The bumpy road to effective hamstring injury prevention in male amateur soccer players

Amateur football players generally deal with an occupation or study or study on top of their football career. These off-field activities could play an important role in hamstring injury occurrence through high load and poor recovery. Therefore, the aim of this study was to explore the causal relation between off-field activities and the development of hamstring injuries in male amateur football players. A total of 399 players filled in a questionnaire concerning off-field activities (i.e. work and study type and hours, travelling time, sleep, and energy costs) and history of injury as a part of a cluster-randomized controlled trial. Throughout one season, both players and medical staff reported injuries weekly. Multivariable Firth corrected logistic regression models were used to explore associations between off-field activities and hamstring injuries. During the season, a total of 65 hamstring injuries were recorded. No evidence was found for causal relations between off-field activities measured at baseline and hamstring injuries. Previous injury was associated with hamstring injuries (OR ranging from 1. 94[1.45-2.61] to 2.01[1.49-2.73]). Future studies should combine the use of sensor technology with subjective measurements to measure on-and off-field activities. When measured frequently enough, a dynamic system approach could detect subtle changes over time.