Analysis of ankle muscle activity: A study on static balance with eyes closed and high-heeled shoes.

ABSTRACT

BACKGROUND: Changes in sensory afferent interfere with the control of postural stability by the central nervous system. Wearing high-heeled shoes is an example of an external disturbance that changes sensory inputs and results in several postural adjustments to control stability. Thus, our purpose is to investigate the influence of high-heeled shoes and visual absence on maintenance of static balance and on ankle muscle activity among young women. Our hypothesis is that the combination of high-heeled shoes with visual absence lead to an increase of postural sway and of levels of activation of the stabilizing ankle muscles. METHODS: Nine volunteers remained in an unrestrained erect posture on a force platform for collecting of stabilometric and electromyographic parameters in four bipodal conditions barefoot with open eyes, barefoot with closed eyes, with high heels and open eyes and with high heels and closed eyes. RESULTS: When comparing the experimental condition open and closed eyes with high heels, there were significant differences for all stabilometric variables, except for the confidence ellipse area. Statistical differences were found for the medial gastrocnemius muscle in all comparison pairs with high heels. CONCLUSION: The wearing high-heeled shoes showed to be the most influencing disturbance on static balance. Our findings suggest ankle muscle activity is adapted according to changes of the center of pressure sway and the wearing of high heels changes the muscle activation and postural sway.