Hypoxic training as a way of the human brain protection from the damaging effects of oxygen deficiency

Abstract

Objective:to evaluate the possibilities of normobaric hypoxic training (NHT) in the human brain protection from the damaging effects of oxygen defciency.Materials and methods:the study involved 18 men, aged 19-23 years, who underwent NHT: 15 treatments daily 2-hour stay in a hypoxic gas medium (HGM) having an oxygen content 15.0 ± 0.5% (HGM-15). Beforestarting the NHT (I phase), and afer 1-2 days afer its closure (II stage) were carried hypoxic samples (staying in HGM-15) before and during which the subjects were recorded the electroencephalogram (EEG) and mental performance were evaluated (the «Route» test).Results:when the frst hypoxic test was carried out, the subjects had a decrease in the alpha-rhythm index (on average by 10-15 %, p = 0.013) and its amplitude (by 10-12 %, p = 0.044) compared to the usual environmental conditions. At the same time, the share of low-amplitude slow waves increased (p = 0.019). Te integral indicator of the «Route» test during staying of the subjects in the HGM-15 decreased on average by 18% compared to the usual conditions (p <0.001). Te obtained data testifed about negative influence of staying in HGM -15 on the functioning of the higher parts of the brain. Afer carrying out NHT, all subjects showed a signifcant reduction in the negative reactions of spontaneous EEG to hypoxia: when the sample was repeated, the alpha-rhythm index and its amplitude did not change signifcantly (in comparison with air breathing), signs of excessive slow wave activity were absent. Reduction of the integral indicator of mental performance when staying in HGM-15 amounted to an average of only 6%.Conclusions:NHT in the developed regime is an effective means of the brain protection from the damaging effect of oxygen defciency and can be used in the system of physiological training of specialists to perform tasks of activity in conditions of reduced partial pressure of oxygen.