Systemic hydration: relating science to clinical practice in vocal health.

OBJECTIVES: To examine the current state of the science regarding the role of systemic hydration in vocal function and health.

STUDY DESIGN: Literature review.

METHODS: Literature search spanning multiple disciplines, including speech-language pathology, nutrition and dietetics, medicine, sports and exercise science, physiology, and biomechanics.

RESULTS: The relationship between hydration and physical function is an area of common interest among multiple professions. Each discipline provides valuable insight into the connection between performance and water balance, as well as complimentary methods of investigation. Existing voice literature suggests a relationship between hydration and voice production; however, the underlying mechanisms are not yet defined and a treatment effect for systemic hydration remains to be demonstrated. Literature from other disciplines sheds light on methodological shortcomings and, in some cases, offers an alternative explanation for observed phenomena.

CONCLUSIONS: A growing body of literature in the field of voice science is documenting a relationship between hydration and vocal function; however, greater understanding is required to guide best practice in the maintenance of vocal health and management of voice disorders. Integration of knowledge and technical expertise from multiple disciplines facilitates analysis of existing literature and provides guidance as to future research.