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Author Spotlight: Integrating Alveolar-Capillary Reserve Measurements in Exercise Adaptation and Therapeutic Strategies
Published on: February 2, 2024
Difference in expiratory flow limitations development in normoxia and hypoxia in healthy individuals
Antoine Raberin1, Giorgio Manferdelli1, Forrest Schorderet1
1Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland.
Abstract:
The present study investigated the maintenance/repeatability of expiratory flow limitation (EFL) between normoxia and hypoxia. Fifty-one healthy active individuals (27 men and 24 women) performed a lung function test and a maximal incremental cycling test in both normoxia and hypoxia (inspired oxygen fraction = 0.14) on two separate visits. During exercise in normoxia, 28 participants exhibited EFL (55 %). In hypoxia, another cohort of 28 participants exhibited EFL. The two groups only partly overlapped. Individuals with EFL only in normoxia reported lower maximal ventilation values in hypoxia than in normoxia (n=5; -13.5 ± 7.8 %) compared to their counterparts with EFL only in hypoxia (n=5; +6.7 ± 6.3 %) or without EFL (n=18; +5.1 ± 10.3 %) (p=0.004 and p<0.001, respectively). EFL development may be induced by different mechanisms in hypoxia vs. normoxia since the individuals who exhibited flow limitation were not the same between the two environmental conditions. This change seems influenced by the magnitude of the maximal ventilation change.
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