Introduction: Balance and postural control are very important factors for normal movement and daily activities. Vibration is a feeling caused by sinusoidal oscillation of objects on the skin. We distunguish between two types of vibration: focal vibration and whole-body vibration. Focal vibration is an innovative technique for balance improvement, especially in various neurological patients. Its effects on a healthy population are still relatively unexplored. Purpose: The purpose of this thesis was to research effects of focal plantar vibration on static balance in a sample of young adults. Methods: A group of 30 physiotherapy students, aged between 20 and 27, participated in the research. Their static balance was tested by standing still on a pressure plate with feet close together and by clinical one-leg standing test on a soft surface with the eyes closed. We then performed local vibration therapy on the plantar side of the foot with Hypervolt device (frequency 30 Hz, amplitude 12 mm). Vibrations were applied sequentially to each sole of the foot in a sitting position for five minutes. After vibration therapy, static balance measurements were performed again and the results of both measurements were compared with each other. We analyzed four parameters of the central pressure movement: the velocity od the central pressure movement, the path, taken by the center in the mediolateral and anteroposterior direction, and the area, calculated by the method of the last values of the covariance matrix. Paired T-test was used to compare the results of central pressure movement and the clinical one-leg standing test before and after vibration therapy. Results: One variable (path in anteroposterior direction) was significantly lower after vibration with open as well as closed eyes and feet together. In the measurements with eyes closed and feet together, there was also a significant difference in the ares, which increased after vibration therapy. Other variables didn't show significant differences between measurements before and after vibration therapy. Measurements of the one-leg test on the soft surface with eyes closed also showed no difference before and after vibration. Discussion and conclusion: Based on obtained results, we can conclude, that after focal plantar vibration in young adults, a very mild effect on static balance is indicated, but there is no significant improvement in balance.
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