Injury risk in professional football players with special reference to the playing position and training periodization.

AIM: The aim of this study was to examine injury incidence in professional football [soccer] players according to the playing positions and with a special reference to training periodization. METHODS: A Spanish professional team was followed prospectively for the 2007-08 and 2008-09 seasons and exposure times and time-loss injuries were individually recorded during all training sessions and matches. Heart rate was monitored in all training sessions. RESULTS: total of 114 injuries were registered during the study period (mean injury incidence: 6.6 injuries per 1000 hours). The frequency of injuries was not uniformly distributed by playing positions (P Language: en