Blood doping is a method used by some athletes to enhance their performance by increasing the number of red blood cells in their bloodstream. This can improve oxygen delivery to muscles, allowing for better endurance and stamina during competitions. Techniques for blood doping include transfusing one's own blood or using synthetic substances like erythropoietin (EPO). This practice is considered unethical and is banned by many sports organizations, including the International Olympic Committee and World Anti-Doping Agency. Athletes caught blood doping can face severe penalties, including suspensions and disqualifications from events.