title: Normoxic and hypoxic performance following 4 weeks of normobaric hypoxic training.
abstract: BACKGROUND
  Although training in hypoxia has been suggested to improve sea level and altitude performance, most studies have only evaluated its effect on maximal aerobic capacity in either normoxia or hypoxia. The present study evaluated the effect of a live low-train high training regimen on both normoxic and hypoxic endurance performance and aerobic capacity.
  
  
  METHODS
  There were 18 male subjects who performed 20 training sessions in either a normoxic (F(IO2) = 0.21) or hypoxic (F(IO2) = 0.12) environment. Both the Control (N = 9) and Hypoxic (N = 9) group subjects trained at an intensity that maintained their heart rate at a level corresponding to that elicited at 50% of peak power output attained in normoxia or hypoxia, respectively. Before, during, upon completion, and 10 d after the protocol, subjects' aerobic capacity (VO2 peak) and endurance performance (80% of VO2 peak) were determined under normoxic and hypoxic conditions.
  
  
  RESULTS
  Mean +/- SD normoxic VO2 peak increased significantly only in the Control group from 45.7 +/- 6.1 to 53.9 +/- 3.9 (ml x kg(-1) x min(-1)), whereas hypoxic VO2 peak did not improve in either group. The Control group exhibited significant improvements in normoxic, but not hypoxic peak power output (PPO) and time to exhaustion, whereas the Hypoxic group only exhibited improvements in normoxic time to exhaustion. During each testing period, we also assessed pulmonary function, selected hematological variables, and anthropometry. There were no significant changes in these variables in either group after the training protocol.
  
  
  CONCLUSIONS
  The hypoxic training regimen used in the present study had no significant effect on altitude and sea level performance.
authors.affiliation: Department of Automation, Biocybernetics and Robotics, Jozef Stefan Institute, Ljubljana, Slovenia. tadej.debevec@ijs.si
authors.forename: Tadej
authors.initials: T
authors.lastname: Debevec
authors.forename: Mojca
authors.initials: M
authors.lastname: Amon
authors.forename: Michail E
authors.initials: ME
authors.lastname: Keramidas
authors.forename: Stylianos N
authors.initials: SN
authors.lastname: Kounalakis
authors.forename: Rado
authors.initials: R
authors.lastname: Pisot
authors.forename: Igor B
authors.initials: IB
authors.lastname: Mekjavic
mesh_terms: D000222:Adaptation, Physiological; D000531:Altitude; D000704:Analysis of Variance; D015444:Exercise; D005080:Exercise Test; D006339:Heart Rate; D006801:Humans; D000860:Hypoxia; D008297:Male; D010101:Oxygen Consumption; D012044:Regression Analysis; D012129:Respiratory Function Tests; D055815:Young Adult