Title: Physiological and cognitive effects of acute normobaric hypoxia,and modulations by oxygen breathing

Abstract : The emergence of normobaric devices for hypoxia awareness training makes crucial the study of physiological and cognitive effects induced by acute normobaric hypoxia (NH) exposure. Our study was aimed i) to investigate the effects of acute NH exposure on physiological variables and working memory; and 2) to investigate the physiological and cognitive effects of oxygen breathing before and after acute NH exposure. METHODS: 86 healthy men were randomized into 4 groups: the Normoxia-Air group (n=23) whose subjects were breathing air; the Hypoxia-Air group (n=22) where NH exposure was preceded and followed by air breathing; the Normoxia-O2 group (n=21) whose protocol was similar to the Normoxia-Air group, except the ad of 100% O2 breathing periods; and the Hypoxia-O2 group (n=20) whose participants were exposed to 100% O2 before and after NH exposure. Working memory was assessed with the Paced Auditory Serial Addition Test. Peripheral oxygen saturation (SpO2), heart rate (HR) and electroencephalogram (EEG) were recorded.