SHORT EXPOSURES TO NORMOBARIC HYPOXIA PROMOTE INCREASED EPO
Frey, W. O., Zenhausen, R., Colombani, P. C., & Fehr, J. (2000). Influence of intermittent exposure to normobaric hypoxia on hematological indexes and exercise performance. Medicine and Science in Sports and Exercise, 32(5), Supplement abstract 165.
Simulated intermittent exposure to normobaric hypoxia is commonly proposed as an ergogenic method. For 21 days, moderately trained Ss (M = 12; F = 6) were exposed daily for 75 minutes at a simulated altitude of 6,400 m. During exposure, Ss received an iron supplement to their normal diet. The length of exposure is shorter than usually reported in this strategy. [No control group or control of extraneous factors were involved in this study.]
There was no influence of the normobaric hypoxia condition on VO2max or power output at lactate levels of 2 and 4 mmol/L. However, erythropoietin was significantly elevated two hours after the first exposition.
Implication. Relatively brief (75 min) normabaric hypoxic exposures have no major physiological effects except a rise in EPO concentrations, which occurs almost immediately after the first exposure.