title: Postexercise cold-water immersion does not attenuate muscle glycogen resynthesis.
abstract: OBJECTIVE
  The aim of this study was to test the hypothesis that postexercise cold-water immersion (CWI, via its associated reductions in skeletal muscle blood flow) attenuates muscle glycogen resynthesis during short-term recovery from exhaustive exercise.
  
  
  METHODS
  In a repeated-measures design, nine recreationally active men performed an exhaustive glycogen depleting cycling protocol (consisting of intermittent exercise the night before and steady-state exercise on the subsequent morning of the main trial) followed by 10 min of lower-limb CWI (8°C) or remained seated in normal ambient conditions (CONT). Subjects were fed carbohydrate (CHO) at an ingestion rate of 0.6 g·kg body mass at 30 min postexercise and at 1, 2, and 3 h postexercise.
  
  
  RESULTS
  Reductions in thigh skin temperature and muscle temperature during postexercise recovery were greater in CWI compared with CONT (P < 0.01). In addition, norepinephrine and blood glucose concentrations were increased and decreased, respectively, during recovery in CWI compared with CONT (P < 0.01). Postexercise muscle glycogen (CONT and CWI postexercise = 76 ± 43 and 77 ± 26 mmol·kg dry weight [dw], respectively; mean ± SD) progressively increased (P < 0.01) during recovery, although rates of resynthesis did not differ (P = 0.719) between conditions (CONT and CWI 4 h postexercise = 160 ± 34 and 157 ± 59 mmol·kg dw, respectively). Total glycogen synthesis during recovery was comparable (CONT and CWI = 83 ± 43 and 79 ± 58 mmol·kg dw, respectively).
  
  
  CONCLUSIONS
  Postexercise CWI does not attenuate muscle glycogen resynthesis rates during short-term recovery even when CHO availability is considered suboptimal. Athletes who regularly incorporate CWI as a recovery strategy to alleviate symptoms of exercise-induced muscle damage should therefore not be concerned with potential negative effects of the associated reductions in muscle blood flow on the restoration of muscle glycogen stores.
authors.affiliation: Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom. W.Gregson@ljmu.ac.uk
authors.forename: Warren
authors.initials: W
authors.lastname: Gregson
authors.forename: Robert
authors.initials: R
authors.lastname: Allan
authors.forename: Susan
authors.initials: S
authors.lastname: Holden
authors.forename: Padraic
authors.initials: P
authors.lastname: Phibbs
authors.forename: Dominic
authors.initials: D
authors.lastname: Doran
authors.forename: Iain
authors.initials: I
authors.lastname: Campbell
authors.forename: Sarah
authors.initials: S
authors.lastname: Waldron
authors.forename: Chang Hwa
authors.initials: CH
authors.lastname: Joo
authors.forename: James P
authors.initials: JP
authors.lastname: Morton
mesh_terms: D000328:Adult; D001494:Baths; D001642:Bicycling / Q000502:physiology*; D015415:Biomarkers / Q000378:metabolism; D001831:Body Temperature; D003080:Cold Temperature; D018592:Cross-Over Studies; D015444:Exercise / Q000502:physiology*; D006003:Glycogen / Q000096:biosynthesis*; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000098:blood supply / Q000378:metabolism*; D013848:Thigh; D055815:Young Adult
chemical_list: D015415:Biomarkers; D006003:Glycogen