Athletes must break their ties with unofficial sponsors of the Olympics from today until three days after Rio 2016 - or face sanctions.
Russian drug cheats will still be competing at the Rio Olympic Games despite recent efforts to target them, whistleblowers tell the BBC.
Doping whistleblower Yuliya Stepanova questions an IOC ruling to ban her from the Rio Olympics.
Indian and Asian shot put champion Inderjeet Singh believes there is a conspiracy against him after he failed a drugs test.
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Olympic 10,000m runner Jo Pavey says the entire Russian team should be banned from competing at the 2016 Olympic Games.