title: The effect of different exercise modalities on dyspnea and leg fatigue in healthy subjects.
abstract: BACKGROUND
  This study documents the impact of different exercise modalities on dyspnea and leg fatigue during equivalent cardiopulmonary stress in healthy subjects.
  
  
  METHODS
  Following a familiarization, 20 subjects (age 21-44 years; 8 males) performed six 5-min exercise tests, randomized among: 2 steep slope treadmill tests (25% grade), 2 lesser slope treadmill tests (12% grade) and 2 bicycle tests on 3 separate days. Subjects reported either dyspnea or leg fatigue during each test. Oxygen consumption (VO2), ventilation (VE), respiratory rate (fR) and heart rate (HR) were measured during each test.
  
  
  RESULTS
  VO2,VE, HR, dyspnea and leg fatigue were not significantly different among the three exercise conditions (p > 0.05).
  
  
  CONCLUSIONS
  These findings indicate that at equivalent levels of cardiopulmonary stress reflected by similar levels of VO2 and heart rate, the perceived level of exertional dyspnea is not influenced by different patterns of neuromuscular activity. Similarly, the intensity of leg fatigue primarily reflects whole body work and is independent of different patterns of neuromuscular activity.
authors.affiliation: Menzies Health Institute of Queensland/ School of Allied Health Sciences, Griffith University, Gold Coast Campus, Australia. Electronic address: pramod.sharma@griffith.edu.au.
authors.forename: Pramod
authors.initials: P
authors.lastname: Sharma
authors.affiliation: Menzies Health Institute of Queensland/ School of Allied Health Sciences, Griffith University, Gold Coast Campus, Australia.
authors.forename: Norman R
authors.initials: NR
authors.lastname: Morris
authors.affiliation: Menzies Health Institute of Queensland/ School of Allied Health Sciences, Griffith University, Gold Coast Campus, Australia.
authors.forename: Lewis
authors.initials: L
authors.lastname: Adams
mesh_terms: D000328:Adult; D001642:Bicycling / Q000502:physiology*; D004417:Dyspnea / Q000503:physiopathology*; D005080:Exercise Test; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007866:Leg / Q000503:physiopathology*; D008297:Male; D018763:Muscle Fatigue / Q000502:physiology*; D010101:Oxygen Consumption / Q000502:physiology; D011897:Random Allocation; D056152:Respiratory Rate / Q000502:physiology; D016138:Walking / Q000502:physiology*; D055815:Young Adult
keywords: Dyspnea; Exercise; Leg fatigue; Oxygen consumption; Ventilation