The physical demands of professional soccer players during in-season field-based training and match-play

The running demands of professional soccer match-play are widely established, with players performing various high-intensity actions interspersed with periods of low-intensity activity. However, the demands of in-season training sessions, and how closely they relate to match-play, remain largely unknown. The purpose of this study was to investigate the running demands of professional soccer players during in-season field-based training sessions and matches, and to examine whether the demands of training are similar to those of competition. Across three competitive seasons, 27 professional soccer players from the Australian A-League (age: 24.9 ± 4.7 yr; body mass: 79.9 ± 7.5 kg; height: 1.82 ± 0.06 m) were monitored during in-season field-based training (n = 184) and competitive matches (n = 57) using global positioning system devices. Non-parametric Mann-Whitney U-tests were used to compare the movement characteristics of training to matches, with significance set at p ≤ 0.05. Results indicated that when compared with matches, players spent significantly more time performing low-speed activities, and less time performing high-speed running, during training (p < 0.001). The relative duration of standing was significantly greater during training than match-play (48.0% vs. 2.7% total time;p < 0.001). The frequency of sprinting efforts was lower during training when compared to match-play (2.1 vs. 8.3 efforts per hour), as was the average speed (68.5 m·min-1 vs. 123.1 m·min-1; p < 0.001). These findings reflect the nature of in-season field-based training practices, where low-intensity activities are promoted to facilitate recovery from matches. Due to the importance of repeated sprint performance in matches, these data highlight the need to examine current training practices, and ensure sufficient high-intensity training stimuli are employed during the competitive season