title: Normobaric Intermittent Hypoxia over 8 Months Does Not Reduce Body Weight and Metabolic Risk Factors--a Randomized, Single Blind, Placebo-Controlled Study in Normobaric Hypoxia and Normobaric Sham Hypoxia.
abstract: OBJECTIVE
  Both a 1- to 4-week continuous or intermittent stay and moderate exercise in hypoxia versus normoxia can lead to weight loss. We examined the reproducibility and durability of added hypoxic exposure in a feasible health program of several months.
  
  
  METHODS
  32 obese persons, randomly assigned to either a hypoxia (age 50.3 ± 10.3 years, BMI 37.9 ± 8.1 kg/m(²)) or a normoxia (age 52.4 ± 7.9 years, BMI 36.3 ± 4.0 kg/m(²)) group, completed 52 exercise sessions within 8 months. Participants exercised for 90 min (65-70% HR(peak)) either at a simulated altitude of 3,500 m or in normoxia, and rested for further 90 min at 4,500 m or normoxia. Before, after 5 weeks, after 3 months, and after the intervention, body composition and exercise capacity were determined. Risk markers (e.g., blood pressure, cholesterol) were measured before, after 3 months, and after the intervention period.
  
  
  RESULTS
  Body weight, BMI, waist and hip circumference, P(peak) and BP(sys) improved over time (p < 0.05) but without group difference. Fat mass reductions correlated with HDL changes (r = -0.427; p < 0.05) in the entire group.
  
  
  CONCLUSIONS
  Long-term, moderate intensity exercise and rest in hypoxia does not lead to higher reductions in body weight than normoxia alone. Therefore, for weight loss and metabolic markers hypoxic exposure does not add effects at least when stimuli (i.e., hypoxia dose, exercise intensity/duration) are unaltered throughout the intervention.
authors.affiliation: Department of Sport Science, Medical Section, University Innsbruck, Innsbruck, Austria.
authors.forename: Hannes
authors.initials: H
authors.lastname: Gatterer
authors.forename: Sven
authors.initials: S
authors.lastname: Haacke
authors.forename: Martin
authors.initials: M
authors.lastname: Burtscher
authors.forename: Martin
authors.initials: M
authors.lastname: Faulhaber
authors.forename: Andreas
authors.initials: A
authors.lastname: Melmer
authors.forename: Christoph
authors.initials: C
authors.lastname: Ebenbichler
authors.forename: Kingman P
authors.initials: KP
authors.lastname: Strohl
authors.forename: Josef
authors.initials: J
authors.lastname: Högel
authors.forename: Nikolaus C
authors.initials: NC
authors.lastname: Netzer
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000328:Adult; D000531:Altitude; D001794:Blood Pressure / Q000502:physiology; D001823:Body Composition; D001835:Body Weight; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology; D002784:Cholesterol / Q000097:blood; D004311:Double-Blind Method; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D000860:Hypoxia; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000628:therapy*; D010100:Oxygen / Q000378:metabolism*; D005082:Physical Exertion; D012307:Risk Factors; D016037:Single-Blind Method
chemical_list: D002784:Cholesterol; D010100:Oxygen