title: Vocal Performance of Group Fitness Instructors Before and After Instruction: Changes in Acoustic Measures and Self-Ratings.
abstract: OBJECTIVE
  (1) To quantify acute changes in acoustic parameters of the voices of group fitness instructors (GFIs) before and after exercise instruction. (2) To determine whether these changes are discernible perceptually by the instructor.
  
  
  METHODS
  This is a pilot prospective cohort study.
  
  
  METHODS
  Participants were six female GFIs, based in Brisbane, Australia. Participants performed a series of vocal tasks before and after instruction of a 60-minute exercise class. Data were obtained pertaining to fundamental frequency (pitch), intensity (volume), jitter, shimmer, harmonic-to-noise ratio (HNR), maximum duration of sustained phonation (MDSP), and pitch range. Additionally, self-ratings of voice quality were obtained before and after instruction. Data were analyzed using the Wilcoxon signed rank test.
  
  
  RESULTS
  Significant increases (P ≤ 0.05) were found in fundamental frequency and intensity after instruction. No significant changes in jitter, shimmer, HNR, or MDSP were found before and after instruction. For the group, no significant change in self-ratings of voice quality occurred before and after instruction.
  
  
  CONCLUSIONS
  Statistically significant changes in pitch and volume were found on acoustic analysis. However, these subtle changes remained within the limits of what is considered normal and representative of the participant's age and gender. Further research into the effects of exercise instruction on the voice is needed.
authors: School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia.
authors: Katherine
authors: K
authors: Dallaston
authors: School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia. Electronic address: a.rumbach@uq.edu.au.
authors: Anna F
authors: AF
authors: Rumbach
mesh_terms: D000162:Acoustics; D000328:Adult; D015444:Exercise; D005260:Female; D006801:Humans; D007587:Job Description; D008144:Loudness Perception; D008875:Middle Aged; D009790:Occupations; D010699:Phonation; D010865:Pilot Projects; D010898:Pitch Perception; D011446:Prospective Studies; D011793:Queensland; D013018:Sound Spectrography; D013061:Speech Acoustics; D013067:Speech Perception; D013068:Speech Production Measurement; D013663:Teaching; D014833:Voice Quality; D055815:Young Adult
keywords: Acoustics; Aerobics instructor; Group fitness instructor; Professional voice use; Vocal loading; Voice disorder