In a TV interview, a witness in a case against Alex Rodriguez has spoken out against the baseball player's use of banned drugs such as testosterone.
A UK newspaper says it had settled with Lance Armstrong after it was made to pay damages over a report which suggested he had used banned substances.
Sprinter Tyson Gay failed more than one drug test this year, recording one of his positives at the US championships in June.
Usain Bolt has insisted he is "clean" and that fans could trust him despite recent failed drugs test by sprint rivals Asafa Powell and Tyson Gay.
Disgraced US cyclist Lance Armstrong says that his former team overlooked allegations of doping because of a lucrative sponsorship deal.
Science is becoming the front-runner in discovering how far the human body can be pushed.
More cheats are being caught, but there are fears that the public will view the problem as endemic.
Former double world sprint champion Tyson Gay has delivered a further body blow to his troubled sport by failing an out-of-competition dope test.
Oscar Pistorius was tested for drugs before and during last year's Paralympic Games in London, says the International Paralympic Committee.
China's anti-doping head has said he was "shocked" after an anti-doping agency alleged the country produces large amounts of illegal substances.
Lance Armstrong's admission to Oprah Winfrey that he was a drugs cheat has thrown a sidelight on to the parallel endurance sport of distance running.
Lance Armstrong's confession has pushed South Africa's anti-doping body to retroactively test blood samples from over 50 top cyclists.
The International Olympic Committee has stripped American cyclist Lance Armstrong of his Sydney Olympics bronze medal, said officials.
Cyclist Lance Armstrong has spent over a decade vehemently defending himself against a litany of doping allegations. Here's a list of his denials.
Lance Armstrong has been mentally preparing himself for a no-holds-barred interview with talk show queen Oprah WInfrey about his history of doping.
Disgraced cyclist Lance Armstrong, is weighing whether to admit he used performance-enhancing drugs, The New York Times has reported.
The fallout has begun and, no, it has nothing to do with the media's role in reporting on the sport, says Richard Poplak.
Lance Armstrong told supporters of his Livestrong cancer charity that it had been a difficult couple of weeks but the foundation's mission must go on.