Can hyperoxic preconditioning in normobaric hypoxia (3500m) improve all-out exercise performance in highly skilled skiers? A randomized, crossover study
MetadataShow full item record
PURPOSE: The purpose of this study was to investigate whether oxygen supplementation immediately prior to exercise (FiO2=1.0) improves all-out exercise performance in normobaric hypoxia (3500m) in highly skilled skiers. METHODS: In this single-blind, randomized, crossover study, 17 subjects performed a 60 s constant-load, all-out test in a normobaric hypoxic chamber. After a short period of adaptation to hypoxia (60 minutes), they received either pure oxygen or chamber air for 5 minutes prior to the all-out test (hyperoxic preconditioning vs. non hyperoxic preconditioning). Capillary blood was collected three times and muscle oxygenation was assessed with near-infrared-spectroscopy (NIRS). RESULTS: Absolute and relative peak power (P=.073 vs. P=.103) as well as mean power (P=.330 vs. P=.569) did not significantly differ after the hyperoxic preconditioning phase. PaO2 increased from 51.3 ± 3 mmHg to 451.9 ± 89.0 mmHg and SaO2 increased from 88.2 ± 1.7% to 100 ± 0.2%, and dropped to 83.8±4.2% after the all-out test. De- (P=.700) and re-oxygenation rates (P=.185) did not significantly differ for both preconditioned settings. CONCLUSIONS: Therefore, we conclude that hyperoxic preconditioning did not enhance 60 s all-out exercise performance in acute hypoxia (3500m).