Effects of Voiced Gargling on the Electrical Activity of Extrinsic Laryngeal Muscles and Vocal Self-assessment

Abstract

To verify the immediate effects of voiced gargling on the electrical activity of extrinsic laryngeal muscles and vocal self-assessment. A sample of 20 individuals of both sexes, mean age of 31.95 (±11.57) years, were equally divided in two groups according to the presence or absence of vocal complaint. Both groups were evaluated by surface electromyography of the suprahyoid (SH) and infrahyoid (IH) muscle areas during rest, phonation of the sustained vowel [Ɛ] in habitual and strong intensities; phonation of rising and falling glissando; and counting from 1 to 10. Surface electromyography was assessed before and after the voiced gargling exercise, which lasted 1 minute. All participants self-rated their voice and phonatory comfort after the exercise. Wilcoxon and Mann-Whitney tests were applied, as well as Fisher's exact test and linear-to-linear test. The level of significance was 5%. The percentage of electrical activity of the SH muscle area decreased in the glissando and counting tasks in the group with vocal complaint, as well as in phonation of sustained vowel in strong intensity in the group without complaint. Decrease was also observed in the right IH muscle area at rest and during sustained vowel phonation at habitual and strong intensities. Percentage of muscular electrical activity was lower in the group with complaint in the following situations: IH muscle area on both sides, at rest and during habitual phonation of sustained vowel and glissando before and after the exercise; right IH muscle area, during counting and strong phonation of sustained vowel before and after exercise; left IH muscle area, in the counting task, just after intervention. Most participants noticed improvement in voice (70%) and phonatory comfort (65%). Voiced gargling during 1 minute promotes immediate effects on the electrical activity of the extrinsic laryngeal muscles in individuals with or without vocal complaint. Most individuals reported improved voice and phonatory comfort after exercise.