Adaptation to intermittent hypoxia: dynamics of blood oxygen saturation and some hematological parameters
Adaptation to hypoxia is an important object of medical research. The aim of this study was to investigate the dynamics of blood oxygen saturation (SpO2), arterial blood pressure (BP), red blood cells, reticulocytes, hemoglobin and erythropoietin (EPO) concentrations during intermittent hypoxic training (IHT). The study was conducted in 11 healthy male volunteers; 2 regimens were tested: 11 and 14 days of IHT at FIO2 = 9%. Exposure to the hypoxic gas mixture caused a reduction in SpO2 by an average of 20.4% (p < 0.05), a 22% increase in the heart rate (p < 0.05) and a 4.5% decrease in diastolic BP (p < 0.05) relative to the initial levels. After 11 days of IHT training, the reticulocyte count was increased by 16.6% (p < 0.05), and there was a distinct tendency to elevated red blood cells (p > 0.05) and hemoglobin (p > 0.05). EPO concentrations declined by 44.2% (p < 0.05) relative to the initial level. Extending the regimen to 14 days resulted in a 3.9% increase in red blood cell count (p < 0.05) and a 4.7% elevation of hemoglobin concentrations (p < 0.05), accompanied by the recovery of the initial reticulocyte count. The applied 2-week IHT regimen resulted in the increased red blood cell count and elevated hemoglobin, suggesting an improvement in the oxygen-carrying capacity of the blood. The proposed regimen can be used to improve physical performance of individuals working in extreme environmental conditions.