In the UEFA injury study, injury incidence was followed for the first team squad of 23 top level teams (among others Arsenal FC, Mann Untd, Chelsea FC, Liverpool FC, FC Inter, AC Milan, Real Madrid, FC Barcelona, FC Porto, SL Benfica) from 2001 to 2008. Traumatic injuries and hamstring strains were more frequent during the competitive season, while overuse injuries were the most common in the preseason period.
The mean total injury incidence was 8/1000 hrs of exposure. The injury incidence was >6 times higher during matches than during training. The injury incidence, both in training and in matches, did not differ between seasons.