Effects of Semi-occluded Vocal Tract Exercises with Different Vibration Sources and Duration on Healthy Adults’ Voice

Abstract

Objectives: This study aimed to explore the impact of semi-occluded vocal tract exercises (SOVTE) with varied vibration sources and durations on the vocal performance of healthy adults. In addition, we sought to confirm the safety of voiced high-frequency oscillation (VHFO) intervention and provide basic data for performances in relation to straw phonation (SP).Methods: The study included 34 healthy adults with no vocal impairments, comprising 8 males and 26 females. The mean age of the participants was 23.00±2.06 years. To assess vocal characteristics during VHFO and SP, voice samples were recorded at three specific time points: prior to performing SOVTE (M0), after 1 minute of exercise (M1), and after 3 minutes of exercise (M3). Cepstral, perturbation, electroglottographic analyses were conducted on the recorded samples of vowel and sentences. Psychometric evaluation was conducted using questionnaires to gauge the self-reported severity of voice and vocal fatigue.Results: No statistically significant differences were observed in the average number of performances or duration per phonation between the two methods. When compared to baseline, CPPV significantly increased after 1 minute and 3 minutes of performance and Acoustic Psychometric Severity Index of Dysphonia decreased after 3 minutes of performance in VHFO. Both methods exhibited no significant differences in terms of psychometric and electroglottographic measurements.Conclusion: Results objectively confirmed the safety of VHFO intervention. This study is clinically significant as it lays the groundwork for future development of optimal treatment regimens and therapeutic programs for voice disorder patients, using foundational data on VHFO.