title: The effect of physical effort on voice characteristics.
abstract: BACKGROUND
  Individuals using their voice intensively during physical effort are at risk for developing voice problems. This study was aimed at examining the influence of physical activity on voice characteristics.
  
  
  METHODS
  Fourteen physical education students (age: 27 ± 4.23 years) were recorded in a resting position, and during mild, moderate, and high exercise intensities (active conditions). Participants were also recorded immediately after each activity, while standing (recovery condition). All recordings were analyzed acoustically.
  
  
  RESULTS
  A significant elevation in the fundamental frequency (F0) was observed with the increase in activity level (p < 0.05). For all other acoustic measures, a gradual increase was observed as the activity level was raised. This increase was statistically significant for a specific set of measures (jitter, PPQ5, and shimmer) during the active conditions. In most cases, significant contrasts were found only between the high activity level and the other levels. During the recovery conditions, a similar increase in values was observed. However, these findings failed to reach statistical significance.
  
  
  CONCLUSIONS
  Findings imply that high levels of physical effort lead to a significant reduction in vocal stability and to an elevation in F0. These changes result from vocal effort and could therefore lead to voice disorders and pathology.
authors.affiliation: Department of Otolaryngology and Head and Neck Surgery, Sheba Medical Center, Tel Hashomer, Israel.
authors.forename: Adi
authors.initials: A
authors.lastname: Primov-Fever
authors.forename: Ronnie
authors.initials: R
authors.lastname: Lidor
authors.forename: Yoav
authors.initials: Y
authors.lastname: Meckel
authors.forename: Ofer
authors.initials: O
authors.lastname: Amir
mesh_terms: D000328:Adult; D015444:Exercise; D005260:Female; D006801:Humans; D008297:Male; D010700:Phonetics; D005082:Physical Exertion; D010809:Physical Fitness; D012146:Rest; D014832:Voice Disorders / Q000209:etiology*; D014833:Voice Quality; D055815:Young Adult