Very few athletes admit to having taken doping substances, but positives in anti-doping controls are constant. Erythropoietin, Nandrolone, Cortisone..., all of them substances of exclusively medical employ, with an almost magical power when used by elite athletes. The athlete that takes them can beat his own record or improve his performance and reach the podium. Dopes can make athletes win medals, a match, a stage... The athlete ends by being the victim of a system that more and more induces to doping. Technicians, clubs and directors benefit from the victories that doping produces, but when the athlete is 'marked' in a control, he is the only one that faces the consequences, not only sportive but also in his health. Athletes who have given 'positives' in controls do not admit taking dope, nor do they blame anybody in their entourage but they all attribute the 'positive' to a scientific error; such is the case of Alberto García, or the footballer Carlos Gurpegui. Only a cyclist, Jesús Manzano, has dared to denounce the doping networks and that has caused him big judiciary problems in our country.