title: Cardiorespiratory and sensory responses to exercise in well-controlled asthmatics.
abstract: OBJECTIVE
  The purpose of this study was to evaluate detailed ventilatory, cardiovascular and sensory responses to cycle exercise in sedentary patients with well-controlled asthma and healthy controls.
  
  
  METHODS
  Subjects included sedentary patients meeting criteria for well-controlled asthma (n = 14), and healthy age- and activity-matched controls (n = 14). Visit 1 included screening for eligibility, medical history, anthropometrics, physical activity assessment, and pre- and post-bronchodilator spirometry. Visit 2 included spirometry and a symptom limited incremental cycle exercise test. Detailed ventilatory, cardiovascular and sensory responses were measured at rest and throughout exercise.
  
  
  RESULTS
  Asthmatics and controls were well matched for age, body mass index and physical activity levels. Baseline forced expiratory volume in 1 second (FEV(1)) was similar between asthmatics and controls (98 ± 10 versus 95 ± 9% predicted, respectively, p > 0.05). No significant differences were observed between asthmatics and controls for maximal oxygen uptake (31.8 ± 5.6 versus 30.6 ± 5.9 ml/kg/min, respectively, p > 0.05) and power output (134 ± 35 versus 144 ± 32 W, respectively, p > 0.05). Minute ventilation (V(E)) relative to maximum voluntary ventilation (V(E)/MVV) was similar between groups at maximal exercise with no subjects showing evidence of ventilatory limitation. Asthmatics and controls achieved similar age-predicted maximum heart rates (92 ± 7 versus 93 ± 8% predicted, respectively, p > 0.05). Ratings of perceived breathing discomfort and leg fatigue were not different between groups throughout exercise.
  
  
  CONCLUSIONS
  The results of this study indicate that sedentary patients with well-controlled asthma have preserved sensory and cardiorespiratory responses to exercise with no evidence of exercise impairment or ventilatory limitation.
authors.affiliation: a Respiratory Physiology Department , National Institute of Respiratory Diseases , Mexico City , Mexico .
authors.forename: Arturo
authors.initials: A
authors.lastname: Cortés-Télles
authors.forename: Luis
authors.initials: L
authors.lastname: Torre-Bouscoulet
authors.forename: Roberto
authors.initials: R
authors.lastname: Mejía-Alfaro
authors.forename: Monica
authors.initials: M
authors.lastname: Silva-Cerón
authors.forename: Sabrina S
authors.initials: SS
authors.lastname: Wilkie
authors.forename: Jordan A
authors.initials: JA
authors.lastname: Guenette
mesh_terms: D000328:Adult; D001249:Asthma / Q000503:physiopathology*; D001837:Body Weights and Measures; D015444:Exercise / Q000502:physiology*; D005260:Female; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D012119:Respiration; D012129:Respiratory Function Tests; D057185:Sedentary Behavior
keywords: Cardiac limitation; cardiopulmonary exercise testing; dyspnea; physiology; ventilation; ventilatory limitation