Effects of intermittent hypoxic training on orthostatic reactions of the cardiorespiratory system.

The possibility of using intermittent hypoxic training for stimulation of physiological mechanisms underlying the compensatory hemodynamic reactions to orthostatic load was studied in animal experiments. Intermittent hypoxic training had a favorable impact on circulatory reactions, which manifested in stabilization of blood pressure and heart filling pressure and in a decrease in orthostatic hypotension during the initial period of orthostasis. We hypothesized that the positive effect of intermittent hypoxic training on the correction of negative hemodynamic shifts is determined by the training effect aimed at the increase in the vascular tone and venous return to the heart. These results can serve as validation for preventive use of intermittent hypoxic training for reducing blood draining in the lower part of the body, correction of the compensatory orthostatic reaction of the circulatory system, and hence, for improvement of orthostatic resistance.