How about:
Blood doping is the practice of boosting the number of red blood cells in the bloodstream in order to enhance athletic performance. Because such blood cells carry oxygen from the lungs to the muscles, a higher concentration in the blood can improve an athletes aerobic capacity (VO2 max) and endurance. Many methods of blood doping are illegal, particularly in professional sports. source Wikipedia
Blood doping for more oxygen — you probably nailed it.
If I were Hillary I most definitely would do that among other things.