Immediate effects of shoes inducing ankle-destabilization around Henke's axis during challenging walking gaits: Gait kinematics and peroneal muscles activities.

Due to its high frequency of occurrence, as well as possible residual symptoms, proper treatment of lateral ankle sprains (LAS) is important. From a physiological point of view, increasing the quantity of electromyographic (EMG) activity in the peroneal muscles will mechanically improve the functional stability of the ankle joint. The present study investigated the immediate effects of an ankle destabilization device (ADD) specifically designed to induce imbalances along the Henke's axis during 3 challenging walking tasks. As the effects of such a device have to be tested on healthy participants before being implemented in rehabilitation programs, 12 healthy participants performed 3 different types of walking (normal, aligned, and jumping walking) while the EMG activities in four peroneal muscles and the main gait kinematics parameters were recorded. Our results clearly demonstrated that wearing the ADD during these different walking tasks significantly increased EMG activities in the four peroneal muscles (increases from 9 to 33% on average depending on the muscle and the walking condition) while maintaining previous gait kinematic patterns. Our study shows that an ADD coupled with walking or jumping tasks is able to improve neuromuscular activity. It should therefore be useful for ankle rehabilitation therapy and the prevention of LAS.