Frequency Transmission of Oscillation from External Whole-Body Vibration Platform to the Larynx.

PURPOSE: This study investigates (1) the presence of frequency transmission of oscillation from an external whole-body vibration (WBV) platform to the larynx; and (2) the factors that influence this frequency transmission.

METHODS

Thirty participants (mean age=22.3years) with normal voice were exposed to four frequency-intensity levels of WBV (10 Hz-10%, 10 Hz-20%, 20 Hz-10%, 20 Hz-20%) and were instructed to produce the natural vowel /a/ three times during each WBV setting. The frequency was extracted from the middle 1-second of each electroglottographic (EGG) signal after passing through a Hann band filter with a range of 6-24 Hz. Linear mixed-effects models were applied to determine the factors that influenced the absolute deviation of the frequency transmission.

RESULTS

All participants exhibit an extracted EGG frequency that aligns with the external WBV frequency, deviating by - 0.6 to 1.2 Hz. The absolute deviation of WBV frequency transmission is consistent for both sexes across various WBV settings, except the 10 Hz-10% setting where men tend to exhibit significantly higher deviations (P = 0.018).

CONCLUSION

Oscillations at a specific frequency are transmitted from an external WBV platform to the larynx. This study proposes the use of a "spring" system to investigate the effect of WBV on the larynx, and recommends further research to explore the potential of WBV in managing voice disorders.