• ACL;
  • climate;
  • epidemiology;
  • Köppen;
  • soccer;
  • weather

The objective of this study was to investigate regional differences in injury incidence in men's professional football in Europe. A nine-season prospective cohort study was carried out between 2001–2002 and 2009–2010 involving 1357 players in 25 teams from nine countries. Teams were categorized into different regions according to the Köppen–Geiger climate classification system. Teams from the northern parts of Europe (n = 20) had higher incidences of injury overall [rate ratio 1.12, 95% confidence interval (CI) 1.06 to 1.20], training injury (rate ratio 1.16, 95% CI 1.05 to 1.27), and severe injury (rate ratio 1.29, 95% CI 1.10 to 1.52), all statistically significant, compared to teams from more southern parts (n = 5). In contrast, the anterior cruciate ligament injury incidence was lower in the northern European teams with a statistically significant difference (rate ratio 0.43, 95% CI 0.25 to 0.77), especially for noncontact anterior cruciate ligament injury (rate ratio 0.19, 95% CI 0.09 to 0.39). In conclusion, this study suggests that there are regional differences in injury incidence of European professional football. However, further studies are needed to identify the underlying causes.