Effect of Whole-body Vibration on Changing Foot Position and Postural Stability in Young Adults - Comparative Study.

Background: Whole-body vibration is commonly used in physiotherapy. The vibration platform generates mechanical stimuli that primarily influence the neuromuscular system. Vibration can improve proprioception and balance. The aim of the study was to assess the impact of whole-body vibration on foot position and postural stability.

Material and methods: A group of 31 participants took part in 6 vibration sessions at 15Hz and 30Hz over 2 weeks. Foot position parameters (angle and distance) and postural stability indicators before and after vibration were assessed on the Biodex Balance System. Vibration was performed on the Galileo Med35 platform (3x3 min). A control group consisted of 26 people who were only assessed on the Biodex platform.

Results: There was no change in the angle of both feet (p>0.05) after vibration at the frequency of 15 Hz. The angle of the right foot increased (p=0.013) after vibration at 30 Hz. Vibration increased the distance between the feet for both 15Hz (p=0.000) and 30Hz (p=0.000) sessions. There was no correlation between the change in feet spacing and the change in the overall stability index, anteroposterior stability index and mediolateral stability index (p>0.05). In the control group, no changes (p>0.05) in the angle and foot spacing were noted between consecutive measurements.

Conclusions: 1. Whole body vibration can increase the width of quadrilateral of support in static conditions but has a minimal effect on changing the angle of the feet. 2. The width of the quadrilateral of support after whole-body vibration does not appear to affect postural stability under static conditions. 3. It is recommended that postural stability is assessed before and after whole body vibration while the initial position of the feet is maintained.