The effect of whole-body vibration on phonation

Abstract

This study investigated the effect of whole body vibration (WBV), set at 30% intensity at 5 Hz and 15 Hz, on phonation with vocal fatigue. Thirty vocally healthy participants were recruited and randomly divided into three groups: received 5 Hz vibration (low frequency group-LFG), received 15 Hz vibration (high frequency group-HFG) and no vibration (control group-CON). All participants were first asked to sing for at least 95 minutes so that vocal fatigue was induced. Participants in the LFG and HFG were then exposed to WBV for 20 times, which each lasted for 30 seconds and, with 30 seconds of rest in between vibrations. Participants in the CON were asked to have vocal rest for 20 minutes. All subjects were required to measure their maximum phonation time (MPT), maximum frequency in a voice range profile and recording a speech task for measuring their vocal attack time (VAT) before and after the vibration. Results demonstrated that MPT in LFG had significant increased following the vibration. This finding suggested that WBV could bring improvements to phonation and respiration coordination.