Lance Armstrong: Doping in sports

POSTED: 12:23 PM PDT July 13, 2011    UPDATED: 10:42 PM PST January 17, 2013 

Lance Armstrong confessed to doping to win the Tour de France during an interview with Oprah Winfrey on Thursday. In sports, doping refers to the use of performance-enhancing drugs and substances taken to mask performance-enhancing drugs in test. Particual types of drugs are banned by sports organizations. Click to find out more.