title: Blood oxidative-stress markers during a high-altitude trek.
abstract: Oxidative stress occurs as a result of altitude-induced hypobaric hypoxia and physical exercise. The effect of exercise on oxidative stress under hypobaric hypoxia is not well understood.
  
  
  OBJECTIVE
  To determine the effect of high-altitude exercise on blood oxidative stress. Nine male participants completed a 2-d trek up and down Mt Rainer, in North America, at a peak altitude of 4,393 m. Day 1 consisted of steady-pace climbing for 6.25 hr to a final elevation of 3,000 m. The 4,393-m summit was reached on Day 2 in approximately 5 hr. Climb-rest intervals varied but were consistent between participants, with approximately 14 hr of total time including rest periods. Blood samples were assayed for biomarkers of oxidative stress and antioxidant potential at the following time points: Pre (before the trek), 3Kup (at ascent to 3,000 m), 3Kdown (at 3,000 m on the descent), and Post (posttrek at base elevation). Blood serum variables included ferric-reducing antioxidant potential (FRAP), Trolox equivalent antioxidant capacity (TEAC), protein carbonyls (PC), and lipid hydroperoxides. Serum FRAP was elevated at 3Kup and 3Kdown compared with Pre and Post values (p = .004, 8% and 11% increase from Pre). Serum TEAC values were increased at 3Kdown and Post (p = .032, 10% and 18% increase from Pre). Serum PC were elevated at 3Kup and 3Kdown time points (p = .034, 194% and 138% increase from Pre), while lipid hydroperoxides were elevated Post only (p = .004, 257% increase from Pre).
  
  
  CONCLUSIONS
  Findings indicate that high-altitude trekking is associated with increased blood oxidative stress.
authors.affiliation: Department of Kinesiology, Auburn University, Auburn, AL, USA.
authors.forename: Lindsey E
authors.initials: LE
authors.lastname: Miller
authors.forename: Graham R
authors.initials: GR
authors.lastname: McGinnis
authors.forename: Brian
authors.initials: B
authors.lastname: Kliszczewicz
authors.forename: Dustin
authors.initials: D
authors.lastname: Slivka
authors.forename: Walter
authors.initials: W
authors.lastname: Hailes
authors.forename: John
authors.initials: J
authors.lastname: Cuddy
authors.forename: Charles
authors.initials: C
authors.lastname: Dumke
authors.forename: Brent
authors.initials: B
authors.lastname: Ruby
authors.forename: John C
authors.initials: JC
authors.lastname: Quindry
mesh_terms: D000293:Adolescent; D000328:Adult; D000531:Altitude; D000975:Antioxidants / Q000378:metabolism*; D006801:Humans; D015227:Lipid Peroxidation; D008297:Male; D008875:Middle Aged; D018384:Oxidative Stress; D050050:Protein Carbonylation; D012146:Rest; D016138:Walking / Q000502:physiology*; D055815:Young Adult
chemical_list: D000975:Antioxidants