Effects of whole body vibration on the phonatory functions in children

Abstract

Whole body vibration (WBV), the transmission of vertical oscillatory motion generated by specially-designed vibrating platforms to human body, was investigated in the present study for the possibility of improving the phonatory functions of healthy children. The study aimed to examine the effects of WBV on the phonatory functions (as measured by maximum phonational frequency range, maximum vocal intensity, maximum phonation time and subjects' self-perception of vocal conditions) of normal children. Twenty typically-developing children were recruited in the present study. The phonatory functions in pre-WBV condition were compared to post-WBV condition to investigate the effects of WBV on the phonatory functions of healthy children. The results revealed that the maximum phonational frequency range (p < .05), maximum vocal intensity (p < .01), and maximum phonation time (p < .001) in post-WBV condition were significantly improved compared with pre-WBV condition. Nevertheless, there was no significant difference in all the 7 statements of the voice questionnaire between pre-WBV and post-WBV conditions. The discrepancy between objective and subjective measures of phonatory functions suggested that further studies of the effects of WBV on phonatory functions of children might be required.