It is natural, appropriate and entirely in accord with the spirit of the project of athletic achievement to explore and then exploit the benefits afforded by new knowledge and new technologies. So-called blood doping — maximizing one's ability effectively to transport oxygen to the muscle fibers by blood transfusions (one's own, or someone else's) — is a brilliant and creative solution, an entirely natural next step once you've tapped out other techniques (such as sleeping at high altitudes, or in oxygen tents).
Source: NPR. Read full article. (link)