The purpose of this study was to examine the time for the electromyographic response of the fibular muscles in the sudden foot inversion in sprained and healthy ankles. Three groups of athletes were tested: one composed by healthy athletes (group 1), one group of athletes with recent history of ankle sprain (group 2), and another group composed by non-athletes with recent history of ankle sprain (group 3). For each individual from the three groups both ankles were tested. Individuals with ankle sprain (groups 2 and 3) were asymptomatic for the last two months prior to the test. A platform able to produce a sudden 20º side inversion of the ankle in the frontal plane simulated an ankle sprain event. Surface electromyography electrodes were placed over the fibular muscles. Times for the electromyographic response of the fibular muscles were obtained and compared between groups. In group 1, the mean electromyographic response times were: 71 ms for the right leg, and 69 ms for the left leg. In group 2, the mean electromyographic response times were: 72 ms for non-sprained ankle, and 74 ms for sprained ankle. In group 3, the mean electromyographic response times were: 72 ms for non-sprained ankle and 73 ms for sprained ankle. Results indicated no statistically significant difference between the right and left legs in group 1, and between non-sprained and sprained ankle in groups 2 and 3 for the fibular muscles. The findings in the present study suggest that the time for the electromyographic response of the fibular muscles to sudden angular displacement of the ankle was not influenced by the ankle sprain.
Time for the electromyographic response; Sprain; Ankle
