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.