Submaximal exercise quantified as percent of normoxic and hyperoxic maximum oxygen uptakes. Journal Article uri icon



  • Maximum oxygen uptake (VO2max) was measured in six college-aged males under normoxic (NVO2max) and hyperoxic (HVO2max; 70% oxygen) conditions. Subjects then randomly performed the following three 20-min submaximal exercise bouts: 75% normoxic VO2max under normoxia (NVO2N), 75% normoxic VO2max under hyperoxia (NVO2H), and 75% hyperoxic VO2max under hyperoxia (HVO2H). Metabolic parameters were obtained at 5-min intervals. Hyperoxia resulted in a 13% increase (P less than 0.01) in VO2max (NVO2max = 3.54 l X min-1 vs HVO2max = 4.00 l X min-1). Significant (P less than 0.05) decreases were observed in VE (ventilation) (13%), epinephrine (37%), norepinephrine (26%), and blood lactate (28%), with no change in oxygen uptake (VO2), carbon dioxide production (VCO2), or respiratory exchange ratio (R) during hyperoxia at the same absolute power output (NVO2N vs NVO2H). However, at the same relative power outputs (NVO2N vs HVO2H) no significant changes in VE, epinephrine, norepinephrine, or blood lactate were observed when hyperoxia and normoxia were compared.

publication date

  • December 1, 1984

has subject area

Date in CU Experts

  • October 28, 2013 1:02 AM

Full Author List

  • Byrnes WC; Mihevic PM; Freedson PS; Horvath SM

author count

  • 4

Other Profiles

International Standard Serial Number (ISSN)

  • 0195-9131

Additional Document Info

start page

  • 572

end page

  • 577


  • 16


  • 6