Effects of Systemic and Local Hydration on Voice

Abstract

Hydration, and its relationship with voice, has been a popular topic of investigation in both clinical and physiological investigations. Normal voice production depends on adequate vocal fold hydration, which involves the presence of water on the vocal fold mucosa (i.e., surface/superficial hydration) and sufficient amounts of intracellular water (i.e., systemic hydration). In addition to protecting the vocal folds during vibration, the mucus barrier overlying the vocal folds lubricates the epithelial surface and enables easy voice production. If water can be added and subtracted from vocal fold tissue, the tissue’s viscosity should be respectively decreased or increased, theoretically producing changes in PTP. Hence, researchers have attempted to change the viscosity of vocal fold tissue by altering the water content of the vocal folds via systemic hydration/dehydration treatments either by increasing or decreasing water consumption, researchers have attempted to modify the viscosity of the surface mucus blanket by having participants inhale dehumidified or humidified air. Again, if the water content of the mucus blanket can be manipulated to be more or less viscous, presumably PTP will vary accordingly.

Recent reviews of the relationship between hydration and vocal fold function report a growing body of evidence that systemic and superficial dehydration alters the viscoelastic properties of the mucosa, having detrimental impacts on aerodynamic and acoustic measures of phonation. It is widely accepted that hydration is a crucial factor for proper vocal function and performance. Professional voice users such as singers, teachers , priests, speech-language pathologists, coaches and many other people whose their jobs are dependant mainly on their voices are advised to hydrate before performing, as increased humidification and hydration facilitate wellness of speaking for long periods as well as singing.