Dorsiflexion And Top Speed In American Professional Soccer At Pre-season And Mid-season

PURPOSE: Throughout matches and training sessions, soccer players can run from one to seven miles with up to sixty high intensity efforts. This physical demand over the course of a season can often lead to overuse, a known contributor to tight musculature. In soccer, the posterior musculature of the shank is of concern due to the consistent rapid eccentric and concentric actions that assist players in reaching top speed. This repetitive motion may contribute to a reduction in dorsiflexion range of motion (ROM) throughout a competitive season, which has been preliminarily investigated. The purpose of this study was to investigate changes in dorsiflexion and top speed measures from preseason to midseason, and the relationship between top speed and dorsiflexion. METHODS: Twenty male United Soccer League (USL1) players were tested for dorsiflexion ROM (DFROM) at the preseason and midseason time points. The Weight Bearing Lunge Test was used to evaluate DFROM. Top speed was tracked through GPS technology at every training session and match. Preseason was defined as organized training sessions and matches that did not contribute to club points. Midseason was defined as all training sessions and matches starting at match one to the first half of the season. The top speed for each week was recorded and averaged for each player. Paired sample t-tests were used to identify differences in DFROM and top speed measures from preseason to midseason. Bivariate correlations were used to investigate the relationships between variables. Significance for all testing was set a priori at p ≤ 0.05. RESULTS: A significant difference between preseason and midseason DFROM in the dominant limb (8.9 ± 2.75 cm vs. 8.21 ± 5.57 cm, p = .05) was observed. No other differences were observed and there were no significant relationships between top speed and DFROM (p > .05). CONCLUSIONS: Results of the current study support what other investigators have observed from pre to post season, that DFROM decreases with competitive soccer play. The decreased DFROM at midseason compared to the scores at preseason suggest it may be beneficial to monitor DFROM throughout the season to mitigate injury risk independent of performance measures such as top speed. Given the lack of relationship observed, DFROM may not influence top speed in professional soccer players.