The relationship between fear of movement and ankle biomechanical strategies in a 180° change of direction task

Objective: To assess the association between fear of movement and ankle biomechanics and timed performance in a 505 agility change of direction (COD) test, and to assess the association between the biomechanical indices with timed performance. Methods: Twenty participants, who play football at a university level or higher, with a history of ankle injuries were recruited. All participants performed three maximal effort 505 agility COD tests. Three-dimensional ankle range of motion (ROM, measured using inertial measurement units) and the average ankle muscle co-activation (tibialis anterior, soleus, and peroneus longus muscles of the affected limb, measured using bipolar surface electromyography) were extracted from the stance phase of the final cutting step. Fear of movement was assessed using the Tampa Scale of Kinesiophobia 11-item (TSK-11) questionnaire. Results: TSK-11 significantly correlated with ankle transverse plane ROM: r = -0.53 (95 %CI -0.79 to -0.11), t = -2.63, P = 0.017. There was no significant association between the COD timed performance and the four ankle biomechanical indices. Conclusions: Greater fear of movement may result in a stiffer turning strategy, which may reduce the risk of injury to the ankle. However, fear of movement is less likely to moderate ankle kinematic and muscle activation strategies that give rise to a performance-injury conflict.