Phonation through a tube in water (water resistance exercising) is commonly used for voice therapy and training to improve phonation balance and ease of phonation. Water resistance can be regulated by tube immersion depth in water. Water bubbling also offers a massage like sensation, and bubbling helps visualizing airflow rate. Airflow rate is low with a longer and wider tube. In order to see whether this impairs or rather improves breath support (airflow control) this study compares two types of tubes.

Methodology
Thirteen healthy participants (18-40 years of age) exercised for one minute by phonating into a tube immersed 10 cm in water. One group (N=5) used a Lax Vox type flexible tube (1cm diameter, 35 cm length), while another group (N=8) used a 2,5 cm wide superlong (2,5 m) flexible tube. Slow, steady bubbling on maximum phonation time was aimed at. Acoustic, aerodynamic, and electroglottographic (EGG) measures and self-evaluation of ease of phonation were assessed pre and post exercising.

Results
The two groups did not differ from each other in the values before exercising. Acoustic Breathiness Index decreased (p 0.029) and ease of phonation increased (p 0.043) after Lax Vox type tube, while after wide superlong tube only ease of phonation increased (p 0.013). No significant changes were seen in air pressure, flow and maximum phonation time measurements.

Conclusion
Both ordinary Lax Vox type tube and particularly the wide superlong tube in water resulted in improved ease of phonation after 1 minute exercising. Future study on breath support training is warranted with a tool that helps monitoring and mechanically changing airflow rate. The effect of exercising time should also be considered.

Rojas, Sandra; Laukkanen, Anne-Marie; Ianiszewski, Alejandro; Marcotti, Anthony