Background: On the one hand, hypoxic exposure may result in progressive brain metabolism disturbance, causing subsequent cognitive impairments. On the other hand, it might also enhance neurogenesis and brain vascularization as well as accelerate cerebral blood flow, leading to cognitive function improvement. The aim of this study was to investigate whether progressive stages of normobaric hypoxia (NH) (FIO2 = 13%, FIO2 = 12%, and FIO2 = 11%) differentially affect post-exposure cognitive performance.
Methods: Fifteen physically active men (age = 23.1 ± 2.1) participated in the study. The Stroop test (ST) was applied to assess cognitive function. To generate NH conditions, a hypoxic normobaric air generator was used.
Results: We observed an executive function impairment ("naming" interference p < 0.05) after NH exposure (FIO2 = 13%). After exposure at FIO2 = 12% and FIO2 = 11%, no changes were observed in the Stroop test. Also, changes in SpO2 during subsequent NH exposure were observed.
Conclusions: The current investigation shows that executive functions deteriorate after acute NH exposure and this post-exposure deterioration is not proportional to the normobaric hypoxia stages among young physically active males.
Keywords: altitude; cognitive function; physical exercise.