The influence of playing level on functional ankle stability in soccer players

The aim of this study was to compare the functional ankle stability between professional and amateur soccer players as well as controls.

Thirty professional soccer players, 30 amateur soccer players and 30 controls were evaluated. All participants completed a questionnaire. Range of motion (ROM), peroneal reaction time (PRT) and ankle position sense were measured. Balance control was investigated with the Biodex Stability System, measuring the stable level 8 and the unstable level 2.

Professional soccer players cited significantly more frequent ankle sprains than all other groups (P = 0.002). They showed a significantly decreased dorsiflexion of the right foot (amateur: P = 0.017; controls: P = 0.004), an increased pronation of both feet (amateurs: right: P = 0.0048, left: P = 0.006; controls: right: P = 0.017, left: P = 0.007) and a decreased supination of the left foot in comparison to all other groups (amateurs: P = 0.003; controls: P = 0.004). Balance control showed no significant differences among all groups. Significant differences in angle reproduction were observed between professionals and amateurs for the left ankle joint at the positions of 105° (P = 0.0018) and 140° (P = 0.013). Professionals (P = 0.004) and amateurs (P = 0.001) showed a significantly delayed PRT of the right peroneus longus muscle compared to controls. In addition, the PRT of the right peroneus brevis muscle was significantly increased in professional soccer players in comparison to controls (P = 0.017).

Professional soccer players have shown more frequent ankle sprains, limited ROM, and delayed PRT of the right leg which reflects the higher risk of functional ankle instability due to intensified work-related use of feet. Therefore, proprioceptive exercises of the ankle in daily training programs are recommended in order to minimize the risk of ankle injuries and improve functional ankle stability.