Olga Danilova

After winning a gold and silver medal in the 2002 Salt Lake City Winter Olympics, Russian-born Olga Danilova was stripped of her medals after banned substances were found in her blood tests.

Jim Thorpe

At one point, Thorpe was considered one of the best athletes the world had ever seen – even winning a couple of gold medals. Sadly they had to be revoked after it came out that he participated in competitions in return for money.