title: Treatment of exercise-induced muscle injury via hyperbaric oxygen therapy.
abstract: OBJECTIVE
  This study examined the role of hyperbaric oxygen therapy (HBO) in the treatment of exercise-induced muscle injury.
  
  
  METHODS
  21 college-aged male volunteers were assigned to three groups: control, immediate HBO (iHBO), and delayed HBO (dHBO). All subjects performed 6 sets (10 repetitions per set) of eccentric repetitions with a load equivalent to 120% of their concentric maximum. HBO treatments consisted of 100-min exposure to 2.5 ATA and 100% oxygen with intermittent breathing of ambient air (30 min at 100% O2, 5 min at 20.93% O2). HBO treatments began either 2 (iHBO) or 24 h (dHBO) postexercise and were administered daily through day 4 postexercise. Forearm flexor cross-sectional area (CSA) and T2 relaxation time via magnetic resonance imaging (MRI) were assessed at baseline, 2, 7, and 15 d postinjury. Isometric strength and rating of perceived soreness of the forearm flexors were assessed at baseline, 1, 2, 3, 4, 7, and 15 d postinjury. Serum creatine kinase (CK) was assessed on day 0 and on days 1, 2, 7, and 15 postinjury.
  
  
  RESULTS
  Mean baseline CSA values were: 2016.3, 1888.5, and 1972.2 mm2 for control, iHBO, and dHBO, respectively. All groups showed significant increases in CSA in response to injury (21% at 2 d, 18% at 7 d) (P < 0.0001), but there were no significant differences between groups (P = 0.438). Mean baseline T2 relaxation times were: 26.18, 26.28, and 27.43 msec for control, iHBO, and dHBO, respectively. Significant increases in T2 relaxation time were observed for all groups (64% at 2 d, 66% at 7 d, and 28% at 15 d) (P < 0.0001), but there were no significant differences between groups (P = 0.692). Isometric strength (P < 0.0001), serum CK levels (P = 0.0007), and rating of perceived soreness (P < 0.0001) also indicated significant muscle injury for all groups, but there were no differences between groups (P = 0.459, P = 0.943, and P = 0.448, respectively).
  
  
  CONCLUSIONS
  These results suggest that hyperbaric oxygen therapy was not effective in the treatment of exercise-induced muscle injury as indicated by the markers evaluated.
authors.affiliation: Department of Kinesiology and Applied Physiology, University of Colorado, Boulder 80309, USA. bcharrison@earthlink.net
authors.forename: B C
authors.initials: BC
authors.lastname: Harrison
authors.forename: D
authors.initials: D
authors.lastname: Robinson
authors.forename: B J
authors.initials: BJ
authors.lastname: Davison
authors.forename: B
authors.initials: B
authors.lastname: Foley
authors.forename: E
authors.initials: E
authors.lastname: Seda
authors.forename: W C
authors.initials: WC
authors.lastname: Byrnes
mesh_terms: D000328:Adult; D003402:Creatine Kinase / Q000097:blood; D015444:Exercise; D006801:Humans; D006931:Hyperbaric Oxygenation; D007537:Isometric Contraction; D008279:Magnetic Resonance Imaging; D008297:Male; D018482:Muscle, Skeletal / Q000293:injuries* / Q000473:pathology / Q000503:physiopathology
chemical_list: D003402:Creatine Kinase