Training-related concussions in men's English Premiership Rugby Union: an eight-season prospective cohort study of 153 243 player-weeks.

OBJECTIVE: To describe the incidence, severity, burden and risk factors of training-related concussion injuries in elite men's Rugby Union. METHODS: Training-related concussions recorded as part of the Professional Rugby Injury Surveillance Project were examined between the 2016/2017 and 2023/2024 seasons. Incidence rates (per 1000 hours) were calculated with 95% CIs. Poisson regression and incidence rate ratios described season-to-season changes in concussion incidence. A generalised linear mixed model assessed the influence of time in season, match minutes played in the previous 28 days, dominant training type and previous concussion as fixed effects, accounting for weekly training exposure. Random intercepts included player and team. RESULTS: The incidence of concussions in training was 0.23 per 1000 hours (95% CI 0.22 to 0.29). The mean severity (days absent) of concussions was 18 days (95% CI 15 to 21). The burden of training concussions was 4.16 days absent per 1000 hours (95% CI 3.57 to 4.85). The tackle (46%) and accidental collisions (26%) were the most common inciting events. The incidence of training-related concussions was significantly higher in the 2021/2022, 2022/2023 and 2023/2024 seasons compared with the 2016/2017 season. Preseason (incidence rate ratio (IRR) 1.80 (95% CI 1.24 to 2.60), p=0.01) and full-contact training (IRR 2.20 (95% CI 1.17 to 4.12), p=0.01) were associated with a higher risk of concussion compared with the final 3 months of the season and non-contact training. CONCLUSION: Full-contact training and the preseason period are associated with an increased risk of training-related concussion. Accordingly, full-contact and preseason training should be strategically planned to minimise risk.