title: Effects of intermittent exposure to hyperbaric oxygen for the treatment of an acute soft tissue injury.
abstract: OBJECTIVE
  To assess the hypothesis that subjects exposed to intermittent hyperbaric oxygen treatments would recover from signs and symptoms indicative of delayed-onset muscle soreness faster than subjects exposed to normoxic air.
  
  
  METHODS
  Randomized, double-blinded study with a 4-day treatment protocol.
  
  
  METHODS
  University-based sports medicine clinic.
  
  
  METHODS
  Sixteen sedentary female university students.
  
  
  METHODS
  All subjects performed 300 maximal voluntary eccentric contractions (30 sets of 10 repetitions per minute) of their nondominant leg (110 to 35 degrees of knee flexion) at a slow speed (30 degrees per second) on a dynamometer to elicit muscle damage and injury. Hyperbaric oxygen treatments consisted of 100% oxygen for 60 minutes at 2.0 atmospheres absolute (ATA), while the control group received 21% oxygen at 1.2 ATA for the same amount of time. Both groups received treatment immediately after the induction of delayed-onset muscle soreness and each day thereafter for a period of 4 days (day 1 postexercise through day 4 postexercise).
  
  
  METHODS
  Dependent variables (perceived muscle soreness, isokinetic strength, quadriceps circumference, creatine kinase, and malondialdehyde) were assessed at baseline (preexercise, day 0), 4 hours postexercise (day 1), 24 hours postexercise (day 2), 48 hours postexercise (day 3), and 72 hours postexercise (day 4). Magnetic resonance images (T2 relaxation time/short tip inversion recovery) were assessed at baseline (day 0), 24 hours postexercise (day 3), and 72 hours postexercise (day 5).
  
  
  RESULTS
  Repeated-measures analysis of variance was performed on all of the dependent variables to assess differences between treatment and control groups. Analyses revealed no significant differences between groups for treatment effects for any of the dependent variables (pain, strength, quadriceps circumference, creatine kinase, malondialdehyde, or magnetic resonance images).
  
  
  CONCLUSIONS
  The findings of this study suggest that hyperbaric oxygen therapy is not effective in the treatment of exercise-induced muscle injury as indicated by the markers evaluated.
authors.affiliation: BC Injury Research & Prevention Unit, Vancouver Hospital & Health Sciences Center, Family Medicine, University of British Columbia, Canada. sbabul@cw.bc.ca
authors.forename: Shelina
authors.initials: S
authors.lastname: Babul
authors.forename: Edward C
authors.initials: EC
authors.lastname: Rhodes
authors.forename: Jack E
authors.initials: JE
authors.lastname: Taunton
authors.forename: Michael
authors.initials: M
authors.lastname: Lepawsky
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D001265:Athletic Injuries / Q000097:blood / Q000150:complications / Q000628:therapy*; D003402:Creatine Kinase / Q000097:blood; D004311:Double-Blind Method; D004487:Edema / Q000209:etiology / Q000628:therapy; D005260:Female; D006801:Humans; D006931:Hyperbaric Oxygenation / Q000379:methods*; D008315:Malondialdehyde / Q000097:blood; D018482:Muscle, Skeletal / Q000293:injuries; D020127:Recovery of Function; D017695:Soft Tissue Injuries / Q000097:blood / Q000150:complications / Q000628:therapy*; D016896:Treatment Outcome
chemical_list: D008315:Malondialdehyde; D003402:Creatine Kinase