Yes, it's true that Armstrong didn't get admit doping because by of the retesting of old samples. It all unraveled with Landis. But Armstrong is a good example

Yes, it's true that Armstrong didn't get admit doping because by of the retesting of old samples. It all unraveled with Landis. But Armstrong is a good example of how people will eventually get caught. In 2005, L'Équipe reported that 6 of his urine samples from the 1999 Tour de France that had been frozen had tested positive for EPO. But since it was part of a research project and had not been properly controlled it couldn't be used against Armstrong. It did add fuel to the speculation that he used drugs.