Endurance Training: Regular aerobic exercise, such as running or cycling, can lead to an increase in the total mass of RBCs and hemoglobin in circulation, which is beneficial for athletic performance.2425
Immediate Response: The body responds to exercise almost immediately by beginning to produce more RBCs, with erythropoietin levels peaking within the first few days of altitude exposure.26
Destruction of RBCs: Although aerobic training leads to increases in RBCs, it can also lead to their accelerated destruction due to factors like increased body temperature and oxidative stress during exercise.25
Adaptation: Over time, the body adapts to regular exercise by increasing the number of RBCs to match the increase in plasma volume, a process that can take about a month.2527
This increase in RBCs helps to improve the oxygen-carrying capacity of the blood, allowing the body to cope with the reduced oxygen availability.2223