LAUSR

Background The association between match congestion and injury rates in professional football has yielded conflicting results. Aim To analyse associations between match congestion on an individual player level and injury rates during professional football matches. Methods Data from a prospective cohort study of professional football with 133 170 match observations were analysed with Poisson regressions. Associations between short-term match congestion, defined as number of days between two match exposures (≤3, 4, 5, 6 and 7–10 days) and injury rates were analysed. To analyse the influence of long-term match congestion, defined as individual match exposure hours in the 30 days preceding a match, observations were categorised into three groups (low, ≤4.5; medium, >4.5 to ≤7.5; and high, >7.5 hours). Results No differences in total match injury rates were found between the reference category (≤3 days) and the other categories of short-term congestion. Muscle injury rates were significantly lower in matches preceded by 6 (rate ratio (RR) 0.79; 95% CI 0.65 to 0.95) or 7–10 days (RR 0.81; 95% CI 0.71 to 0.93) compared with ≤3 days since the last match exposure. No differences in total and muscle injury rates between the three long-term match congestion groups were found. Conclusions In this study of male professional football players, there were no match congestion-related differences in total match injury rates, but muscle injury rates during matches were lower when players were given at least 6 days between their match exposures.