HYPOBARIC EXPOSURES DO NOT AFFECT ATHLETES’ HEMODYNAMICS
Shiller, S. M., Townsend, N., Fu, Q., Martini, E., Williams, K., Rodriguez, F., Gore, C., Truijens, M., Stray-Gundersen, J., & Levine, B. (2004). Hemodynamic responses to intermittent hypoxia exposure in trained athletes. Medicine and Science in Sports and Exercise, 36(5), Supplement abstract 2309.
This study determined whether intermittent hypoxia causes detrimental hemodynamic effects in healthy trained athletes. Swimmers (M = 5; F = 6), and runners (M = 6, F = 5) were randomized and assigned to either hypobaric hypoxia (simulated altitude of 4,000-5,500m) or normoxia (0-5,000m) in a double-blind, placebo controlled design. Both groups rested in a hypobaric chamber three hours per day, five days per week, for four weeks. Hemodynamic measurements including blood pressure, heart rate, cardiac output, total peripheral resistance, and stroke volume were conducted twice before and three days after the last chamber exposure in the sitting position.
No changes in any variable were recorded after the exposure.
Implication. Intermittent hypobaric hypoxia does not alter any aspect of hemodynamics in young endurance trained athletes.