title: Influence of postexercise cooling on muscle oxygenation and blood volume changes.
abstract: OBJECTIVE
  The aim of this study was to investigate the effects of postexercise cold water immersion (CWI) on tissue oxygenation and blood volume changes after intense exercise.
  
  
  METHODS
  Nine physically active men performed 30 min of continuous running (CR) at 70% of their maximal treadmill velocity (Vmax), followed by 10 bouts of intermittent running at Vmax. After exercise, one of the participants' legs was immersed in a cold water bath (10°C, CWI) to the level of their gluteal fold for 15 min. The contralateral leg remained outside the water bath and served as a control (CON). Vastus lateralis (VL) skin temperature (TskVL), VL oxygenation (tissue oxygenation index [TOI]), and blood volume changes (total hemoglobin [tHb] volume) were monitored continuously throughout exercise and CWI using near-infrared spectroscopy.
  
  
  RESULTS
  TskVL, TOI, and tHb were not significantly different between CON and CWI during continuous running and intermittent running, respectively (P > 0.05). In contrast, TskVL was significantly lower in CWI compared with CON throughout immersion, with peak differences occurring at the end of immersion (CON = 35.1 ± 0.6 vs CWI = 16.9°C ± 1.7°C, P < 0.001). tHb was significantly lower during CWI compared with CON at most time points, with peak differences of 20% ± 4% evident at the end of the 15-min immersion (P < 0.01). Likewise, TOI was significantly higher in CWI compared with CON, with peak differences of 2.5% ± 1% evident at the 12th min of immersion (P < 0.05).
  
  
  CONCLUSIONS
  Postexercise cooling decreased microvascular perfusion and muscle metabolic activity. These findings are consistent with the suggested mechanisms by which CWI is hypothesized to improve local muscle recovery.
authors.affiliation: Centre for Exercise and Sports Science Research, School of Exercise and Health Sciences, Edith Cowan University, Joondalup, WA, Australia. m.abdullah@ecu.edu.au
authors.forename: Mohammed
authors.initials: M
authors.lastname: Ihsan
authors.forename: Greig
authors.initials: G
authors.lastname: Watson
authors.forename: Marcin
authors.initials: M
authors.lastname: Lipski
authors.forename: Chris R
authors.initials: CR
authors.lastname: Abbiss
mesh_terms: D000328:Adult; D001810:Blood Volume; D003080:Cold Temperature; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D006801:Humans; D007101:Immersion; D008297:Male; D018482:Muscle, Skeletal / Q000098:blood supply / Q000502:physiology*; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption; D005082:Physical Exertion; D012039:Regional Blood Flow; D019265:Spectroscopy, Near-Infrared; D055815:Young Adult
chemical_list: D010100:Oxygen