Why do athletes remove Red blood cells from their bodies?

Answer 1

This is for the process known as "blood doping," which is almost always prohibited under athletic competition rules.

The athletes are trying to gain an advantage over other athletes by increasing the amount of oxygen their bodies can deliver to the muscles in a competition. The body ordinarily regulates the number of red blood cells that are maintained in the blood. But they can artificially increase this number before a competition (such as a race) by receiving a transfusion of their own red blood cells that were previously removed.

They have their blood drawn weeks before the race, and separate out the red blood cells (constituent known as PRBC for packed red blood cells). The day of the race, they get back a transfusion of these cells, and it takes a few days for the body to remove the excess cells. In the meantime, they can run farther or faster with this additional oxygen-carrying capability.

Along with drugs that stimulate red blood cell production, this process risks several metabolic conditions. High cell counts, known as polycythemia, can result in slower blood flow and excessive strain on the heart.