How Stressful Is "Deep Bubbling"?
OBJECTIVE
Water resistance therapy by phonating through a tube into the water is used to treat dysphonia. Deep submersion (≥10 cm in water, "deep bubbling") is used for hypofunctional voice disorders. Using it with caution is recommended to avoid vocal overloading. This experimental study aimed to investigate how strenuous "deep bubbling" is.


METHODS
Fourteen subjects, half of them with voice training, repeated the syllable [pa:] in comfortable speaking pitch and loudness, loudly, and in strained voice. Thereafter, they phonated a vowel-like sound both in comfortable loudness and loudly into a glass resonance tube immersed 10 cm into the water.


METHODS
Oral pressure, contact quotient (CQ, calculated from electroglottographic signal), and sound pressure level were studied. The peak oral pressure P(oral) during [p] and shuttering of the outer end of the tube was measured to estimate the subglottic pressure P(sub) and the mean P(oral) during vowel portions to enable calculation of transglottic pressure P(trans). Sensations during phonation were reported with an open-ended interview.


RESULTS
P(sub) and P(oral) were higher in "deep bubbling" and P(trans) lower than in loud syllable phonation, but the CQ did not differ significantly. Similar results were obtained for the comparison between loud "deep bubbling" and strained phonation, although P(sub) did not differ significantly. Most of the subjects reported "deep bubbling" to be stressful only for respiratory and lip muscles. No big differences were found between trained and untrained subjects.


CONCLUSIONS
The CQ values suggest that "deep bubbling" may increase vocal fold loading. Further studies should address impact stress during water resistance exercises.
Speech and Voice Research Laboratory, University of Tampere, Tampere, Finland.. Electronic address: jaana.tyrmi@uta.fi.
Jaana
J
Tyrmi
Speech and Voice Research Laboratory, University of Tampere, Tampere, Finland.
Anne-Maria
AM
Laukkanen
D000162:Acoustics / Q000295:instrumentation; D000328:Adult; D055154:Dysphonia / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D004568:Electrodiagnosis; D004867:Equipment Design; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D010699:Phonation; D011312:Pressure; D013016:Sound; D013061:Speech Acoustics; D013997:Time Factors; D014160:Transducers, Pressure; D014827:Vocal Cords / Q000502:physiology*; D014833:Voice Quality; D014834:Voice Training; D014867:Water
D014867:Water
contact quotient; impact stress; resonance tubes; vocal loading; water resistance therapy