title: The Effect of Hydration on the Voice Quality of Future Professional Vocal Performers.
abstract: OBJECTIVE
  The application of systemic hydration as an instrument for optimal voice quality has been a common practice by several professional voice users over the years. Although the physiological action has been determined, the benefits on acoustic and perceptual characteristics are relatively unknown. The present study aimed to determine whether systemic hydration has beneficial outcomes on the voice quality of future professional voice users.
  
  
  METHODS
  A within-subject, pretest posttest design is applied to determine quantitative research results of female singing students between 18 and 32 years of age without a history of voice pathology.
  
  
  METHODS
  Acoustic and perceptual data were collected before and after a 2-hour singing rehearsal. The difference between the hypohydrated condition (controlled) and the hydrated condition (experimental) and the relationship between adequate hydration and acoustic and perceptual parameters of voice was then investigated.
  
  
  RESULTS
  A statistical significant (P = 0.041) increase in jitter values were obtained for the hypohydrated condition. Increased maximum phonation time (MPT/z/) and higher maximum frequency for hydration indicated further statistical significant changes in voice quality (P = 0.028 and P = 0.015, respectively).
  
  
  CONCLUSIONS
  Systemic hydration has positive outcomes on perceptual and acoustic parameters of voice quality for future professional singers. The singer's ability to sustain notes for longer and reach higher frequencies may reflect well in performances. Any positive change in voice quality may benefit the singer's occupational success and subsequently their social, emotional, and vocational well-being. More research evidence is needed to determine the parameters for implementing adequate hydration in vocal hygiene programs.
authors.affiliation: Department of Speech-language Pathology and Audiology, University of Pretoria, Corner of Roper and Lynnwood Road, Pretoria, Gauteng, South Africa.
authors.forename: Liezl
authors.initials: L
authors.lastname: van Wyk
authors.affiliation: Department of Speech-language Pathology and Audiology, University of Pretoria, Corner of Roper and Lynnwood Road, Pretoria, Gauteng, South Africa.
authors.forename: Mariaan
authors.initials: M
authors.lastname: Cloete
authors.affiliation: Department of Speech-language Pathology and Audiology, University of Pretoria, Corner of Roper and Lynnwood Road, Pretoria, Gauteng, South Africa.
authors.forename: Danel
authors.initials: D
authors.lastname: Hattingh
authors.affiliation: Department of Speech-language Pathology and Audiology, University of Pretoria, Corner of Roper and Lynnwood Road, Pretoria, Gauteng, South Africa.. Electronic address: jeannie.vanderlinde@up.ac.za.
authors.forename: Jeannie
authors.initials: J
authors.lastname: van der Linde
authors.affiliation: Department of Speech-language Pathology and Audiology, University of Pretoria, Corner of Roper and Lynnwood Road, Pretoria, Gauteng, South Africa.
authors.forename: Salome
authors.initials: S
authors.lastname: Geertsema
mesh_terms: D000162:Acoustics; D000293:Adolescent; D000328:Adult; D001307:Auditory Perception; D004326:Drinking; D005260:Female; D006801:Humans; D007600:Judgment; D016272:Occupational Health; D063346:Singing; D014833:Voice Quality; D014882:Water-Electrolyte Balance; D055815:Young Adult
keywords: Professional voice users; Systemic hydration; Vocal hygiene; Vocal performers; Voice quality