title: Effect of hydration status on high-intensity rowing performance and immune function.
abstract: OBJECTIVE
  This study determined the effect of dehydration and rehydration (DR) on performance, immune cell response, and tympanic temperature after high-intensity rowing exercise.
  
  
  METHODS
  Seven oarswomen completed two simulated 2000-m rowing race trials separated by 72 h in a random, cross-over design. One trial was completed in a euhydrated (E) condition and the other using a DR protocol.
  
  
  RESULTS
  The DR condition resulted in a 3.33+/-0.14% reduction in body mass (P<.05) over a 24-h period followed by a 2-h rehydration period immediately before the simulated rowing race. There was a greater change in tympanic temperature observed in the DR trial (P<.05). There were increases in the blood concentration of leukocytes, lymphocytes, lymphocyte subsets (CD3+, CD3+/4+, CD3+/8+, CD3-/16+, CD4+/25+; P<.05) and decreases in lymphocyte proliferation and neutrophil oxidative burst activity immediately following the simulated race (P<.05) in both trials. Blood leukocyte and neutrophil concentrations were greater after exercise in the DR trial (P<.05). Whereas most immune measures returned to resting values after 60 min of recovery in both trials, lymphocyte proliferation and the concentrations of CD3+/4+ and CD4+/25+ cells were significantly lower than before exercise. Blood leukocyte and neutrophil concentrations were significantly higher before and after exercise in the E trial.
  
  
  CONCLUSIONS
  The effects of dehydration/rehydration did not negatively influence simulated 2000-m rowing race performance in lightweight oarswomen but did produce a higher tympanic temperature and had a differential effect on blood leukocyte, neutrophil, and natural killer (CD3-/16+) cell concentrations after exercise compared with the euhydrated state.
authors.affiliation: Faculty of Physical Education and Recreation, Department of Agricultural, Food, and Nutritional Science, University of Alberta, Edmonton, AB, Canada.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Penkman
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Field
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Sellar
authors.forename: Vicki J
authors.initials: VJ
authors.lastname: Harber
authors.forename: Gordon J
authors.initials: GJ
authors.lastname: Bell
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D003681:Dehydration / Q000503:physiopathology*; D017079:Exercise Tolerance; D005260:Female; D006801:Humans; D007107:Immune System; D007113:Immunity, Innate; D008214:Lymphocytes; D009504:Neutrophils; D018384:Oxidative Stress; D012767:Ships; D011795:Surveys and Questionnaires; D013601:T-Lymphocytes; D013647:Task Performance and Analysis