BACKGROUND AND OBJECTIVE: Functional ankle instability (FAI) is one of the most commonly debilitating complications of acute ankle sprain, which often results in the athlete staying away from exercise for a while. Disorder in the mechanism of feedforward neuromuscular control can be one of the main reasons for this issue. Musculoskeletal pre-activity during landing is an important indicator of this kind of control. The aim of this study was to compare the sequence of pre-activity of leg muscles between athletes with functional ankle instability and healthy athletes during landing from a jump.
METHODS: This cross-sectional study was conducted among 2 groups of athletes including 12 athletes with functional ankle instability and 12 athletes with healthy athletes. The onset of pre-activity of fibularis longus, tibialis anterior and soleus muscles, was recorded and compared using the surface electromyography during landing from a jump.
FINDINGS: The onset of pre-activity of fibularis longus, tibialis anterior and soleus muscles in athletes with functional ankle instability (163.44±24.92, 140.75±13.54 and 169.67±41.13 milliseconds, respectively) was slower than and healthy athletes (242.75±34.15, 208.71±26.44 and 247.11±26.37 milliseconds, respectively) during landing from a jump (p<0.01).
CONCLUSION: Results of the present study indicated that the onset of pre-activity of fibularis longus, tibialis anterior and soleus muscles in athletes with functional ankle instability was slower than healthy athletes during landing from a jump.