title: Bilevel exercise training and directed breathing relieves exertional dyspnea for male smokers.
abstract: OBJECTIVE
  The purpose of this study was to compare the effects on exertional dyspnea and exercise capacity of square wave (bilevel) cycle ergometry endurance exercise training (SWEET) and comprehensive directed breathing vs. walking while pushing an OxCar and traditional diaphragmatic breathing for male smokers with normal spirometry but reduced exercise capacity.
  
  
  METHODS
  This was a prospective randomized trial of 24 unmedicated men with exertional dyspnea assigned to SWEET or OxCar groups. Exertional dyspnea was assessed using the Borg scale during four tests: incremental exercise, constant exercise at 80% of the peak work rate (PWR) (maximum tolerated for 3 mins before exhaustion), SWEET, and 6-min walk test. Both groups trained for 45 mins, 5 days a week, for 6 wks. Before, during, and after training, 32 lung function parameters were studied at ventilatory anaerobic threshold, at PWR, and during incremental exercise (30 W/3 mins).
  
  
  RESULTS
  For the SWEET group, exertional dyspnea and the dyspnea index decreased during incremental exercise, at the ventilatory anaerobic threshold, and at PWR (P < 0.01). At the ventilatory anaerobic threshold, oxygen consumption increased by 74%; minute ventilation, 30%; tidal volume, 91%; and ventilatory efficiency and oxygen pulse (O(2)P), 25%; and breathing rate (breathing frequency) decreased by 32% (all significant at P < 0.001). At PWR, oxygen consumption increased by 30%; minute ventilation, 37%; breathing rate, 21%; and ventilatory efficiency and oxygen pulse, 25% (P < 0.01). During the full incremental test, minute ventilation, breathing frequency, and heart rate (cardiac frequency) decreased significantly (P < 0.01). In addition, there was significant improvement (P < 0.001) in SWEET intensity by 63%, constant exercise intensity at 80% of PWR by 38%, and 6-min walk test by 30%. No significant changes were observed for the OxCar group other than for the 6-min walk test, which increased by 7% (P < 0.05).
  
  
  CONCLUSIONS
  This study suggests that the decline in exercise tolerance for male smokers can be reduced by intensive exercise training (SWEET) and comprehensive directed breathing but not by moderate training and traditional diaphragmatic breathing. Thus, some smokers can be helped despite continuing to smoke.
authors: Institut National de la Santé et de la Recherche Médicale, Faculté de Médecine, Vandoeuvre-les-Nancy, France.
authors: Manuel
authors: M
authors: Gimenez
authors: Pedro
authors: P
authors: Saavedra
authors: Nieves
authors: N
authors: Martin
authors: Jean Marie
authors: JM
authors: Polu
authors: Daniel
authors: D
authors: López
authors: Arturo
authors: A
authors: Gómez
authors: Emilio
authors: E
authors: Servera
mesh_terms: D000328:Adult; D015308:Anaerobic Threshold / Q000502:physiology; D001784:Blood Gas Analysis; D004417:Dyspnea / Q000175:diagnosis* / Q000209:etiology / Q000534:rehabilitation*; D016552:Ergometry / Q000379:methods; D005081:Exercise Therapy / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology*; D006801:Humans; D008297:Male; D005082:Physical Exertion / Q000502:physiology*; D011446:Prospective Studies; D012016:Reference Values; D012129:Respiratory Function Tests; D018570:Risk Assessment; D012720:Severity of Illness Index; D012907:Smoking / Q000009:adverse effects*; D016138:Walking / Q000502:physiology