Introduction: Changes in invertor and evertor muscle torque is one of the sensory-motor disabilities along with functional ankle instability (FAI). According to positive advantages of whole body vibration (WBV) on muscle torque, this study has been conducted to evaluate the effect of WBV on evertor to invertor muscle concentric ratio in people with FAI. Materials and Methods: 30 female with FAI assigned randomly into experimental and control groups. The experimental group received 6 weeks WBV (3 times per weeks). Then they were evaluated according to their evertor and invertor muscle concent ric torque. Concentric muscle torque was evaluated by Biodex Isokinetic. Results: There were no significant differences between concentric torque of evertor and invertor muscles (P> 0.05). WBV could improve concentric torque of invertor and evertor muscles in the ankle of people with FAI (P< 0.05). Conclusion: 6 weeks WBV (18 sessions) can increase concentric torque of evertor and invertor muscles in people with FAI. � 2016, Semnan University of Medical Sciences. All Rights Reserved
