The Influence of Exercise on Cognitive Performance in Normobaric Hypoxia.

Although previous reports indicate that exercise improves cognitive function in normoxia, the influence of exercise on cognitive function in hypoxia is unknown. The purpose of this study was to determine if the impaired cognitive function in hypoxia can be restored by low to moderate intensity exercise. Sixteen young healthy men completed the ANAM versions of the Go/No-Go task (GNT) and Running Memory Continuous Performance Task (RMCPT) in normoxia to serve as baseline (B-Norm) (21% O2). Following 60 minutes of exposure to normobaric hypoxia (B-Hypo) (12.5% O2), these tests were repeated at rest and during cycling exercise at 40% and 60% of adjusted Vo2max. At B-Hypo, the % correct (p≤0.001) and throughput score (p≤0.001) in RMCPT were significantly impaired compared to B-Norm. During exercise at 40% (p=0.023) and 60% (p=0.006) of adjusted Vo2max, the throughput score in RMCPT improved compared to B-Hypo, and there was no significant difference in throughput score between the two exercise intensities. Mean reaction time also improved at both exercise intensities compared to B-Hypo (p≤0.028). Both peripheral oxygen saturation (Spo2) and regional cerebral oxygen saturation (rSo2) significantly decreased during B-Hypo (p≤0.001) and further decreased at 40% (p≤0.05) and 60% (p≤0.039) exercise. There was no significant difference in Spo2 or rSo2 between two exercise intensities. These data indicate that low to moderate exercise (i.e., 40%-60% adjusted Vo2max) may attenuate the risk of impaired cognitive function that occurs in hypoxic conditions.