title: Supplemental Oxygen During High-Intensity Exercise Training in Nonhypoxemic Chronic Obstructive Pulmonary Disease.
abstract: BACKGROUND
  Physical exercise training is an evidence-based treatment in chronic obstructive pulmonary disease, and patients' peak work rate is associated with reduced chronic obstructive pulmonary disease mortality. We assessed whether supplemental oxygen during exercise training in nonhypoxemic patients with chronic obstructive pulmonary disease might lead to superior training outcomes, including improved peak work rate.
  
  
  METHODS
  This was a randomized, double-blind, controlled, crossover trial. Twenty-nine patients with chronic obstructive pulmonary disease (aged 63.5 ± 5.9 years; forced expiratory volume in 1 second percent predicted, 46.4 ± 8.6) completed 2 consecutive 6-week periods of endurance and strength training with progressive intensity, which was performed 3 times per week with supplemental oxygen or compressed medical air (flow via nasal cannula: 10 L/min). Each session of electrocardiography-controlled interval cycling lasted 31 minutes and consisted of a warm-up, 7 cycles of 1-minute intervals at 70% to 80% of peak work rate alternating with 2 minutes of active recovery, and final cooldown. Thereafter, patients completed 8 strength-training exercises of 1 set each with 8 to 15 repetitions to failure. Change in peak work rate was the primary study end point.
  
  
  RESULTS
  The increase in peak work rate was more than twice as high when patients exercised with supplemental oxygen compared with medical air (0.16 ± 0.02 W/kg vs 0.07 ± 0.02 W/kg; P < .001), which was consistent with all other secondary study end points related to exercise capacity. The impact of oxygen on peak work rate was 39.1% of the overall training effect, whereas it had no influence on strength gain (P > .1 for all exercises).
  
  
  CONCLUSIONS
  We report that supplemental oxygen in nonhypoxemic chronic obstructive pulmonary disease doubled the effect of endurance training but had no effect on strength gain.
authors.affiliation: University Institute of Sports Medicine, Prevention and Rehabilitation, Paracelsus Medical University of Salzburg, Austria; Research Institute for Molecular Sports Medicine and Rehabilitation, Paracelsus Medical University of Salzburg, Austria; Sport and Exercise Medicine Division, Department of Medicine, University of Padova, Italy.
authors.forename: Daniel
authors.initials: D
authors.lastname: Neunhäuserer
authors.affiliation: University Institute of Sports Medicine, Prevention and Rehabilitation, Paracelsus Medical University of Salzburg, Austria; Research Institute for Molecular Sports Medicine and Rehabilitation, Paracelsus Medical University of Salzburg, Austria.
authors.forename: Eva
authors.initials: E
authors.lastname: Steidle-Kloc
authors.affiliation: University Clinic of Pneumology, Paracelsus Medical University of Salzburg, Austria.
authors.forename: Gertraud
authors.initials: G
authors.lastname: Weiss
authors.affiliation: University Clinic of Pneumology, Paracelsus Medical University of Salzburg, Austria.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Kaiser
authors.affiliation: University Institute of Sports Medicine, Prevention and Rehabilitation, Paracelsus Medical University of Salzburg, Austria; Research Institute for Molecular Sports Medicine and Rehabilitation, Paracelsus Medical University of Salzburg, Austria; Division of Cardiology, University Heart Centre, University Hospital Zurich, Switzerland.
authors.forename: David
authors.initials: D
authors.lastname: Niederseer
authors.affiliation: First Internal Department of Pulmonary Medicine, Otto-Wagner Hospital, Vienna, Austria.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Hartl
authors.affiliation: University Institute of Sports Medicine, Prevention and Rehabilitation, Paracelsus Medical University of Salzburg, Austria; Research Institute for Molecular Sports Medicine and Rehabilitation, Paracelsus Medical University of Salzburg, Austria.
authors.forename: Marcus
authors.initials: M
authors.lastname: Tschentscher
authors.affiliation: University Institute of Sports Medicine, Prevention and Rehabilitation, Paracelsus Medical University of Salzburg, Austria; Research Institute for Molecular Sports Medicine and Rehabilitation, Paracelsus Medical University of Salzburg, Austria.
authors.forename: Andreas
authors.initials: A
authors.lastname: Egger
authors.affiliation: University Institute of Sports Medicine, Prevention and Rehabilitation, Paracelsus Medical University of Salzburg, Austria; Research Institute for Molecular Sports Medicine and Rehabilitation, Paracelsus Medical University of Salzburg, Austria.
authors.forename: Martin
authors.initials: M
authors.lastname: Schönfelder
authors.affiliation: University Clinic of Pneumology, Paracelsus Medical University of Salzburg, Austria; Department of Pulmonary Medicine, Faculty of Medicine, Kepler-University-Hospital, Johannes Kepler University, Linz, Austria.
authors.forename: Bernd
authors.initials: B
authors.lastname: Lamprecht
authors.affiliation: University Clinic of Pneumology, Paracelsus Medical University of Salzburg, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Studnicka
authors.affiliation: University Institute of Sports Medicine, Prevention and Rehabilitation, Paracelsus Medical University of Salzburg, Austria; Research Institute for Molecular Sports Medicine and Rehabilitation, Paracelsus Medical University of Salzburg, Austria. Electronic address: j.niebauer@salk.at.
authors.forename: Josef
authors.initials: J
authors.lastname: Niebauer
mesh_terms: D000368:Aged; D018592:Cross-Over Studies; D004311:Double-Blind Method; D004562:Electrocardiography; D015444:Exercise; D005080:Exercise Test; D005081:Exercise Therapy / Q000379:methods; D017079:Exercise Tolerance; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D010807:Physical Endurance; D029424:Pulmonary Disease, Chronic Obstructive / Q000503:physiopathology / Q000534:rehabilitation*; D055070:Resistance Training / Q000379:methods*
keywords: Chronic obstructive pulmonary disease; Dyspnea; Exercise capacity; Interval training; Strength training