Question

why is it an advantage to have More red cells at high altitude​

Answer 1

Answer:

In high-altitude environments, you draw in less oxygen per breath than you would at lower altitudes. That means each breath will deliver less oxygen to your muscles. ... As elite athletes acclimate to high altitude, they acquire more red blood cells which allows their blood to carry more oxygen

Answer 2

They do this because the air is "thinner" at high altitudes meaning there are fewer oxygen molecules per volume of air. ... To compensate for the decrease in oxygen, one of the body's hormones, erythropoietin (EPO), triggers the production of more red blood cells to aid in oxygen delivery to the muscles.