Former world sprint champion Tyson Gay has been suspended for one year, after the American tested positive for a banned substance last July.
Gay will be allowed to return to competition in June.
He has also returned the silver medal he won with the US 4x100 metres relay team at the 2012 London Olympics.
As part of the suspension, Gay, the joint second fastest man in history, was disqualified from all competitive results since July 15, the date he first used a product that contained a prohibited substance.
The American 100 metres record holder had tearfully admitted last July he had failed an out-of-competition doping test.
The 31-year-old could have been suspended for two years for his first doping offence but received a reduction because of his substantial assistance into the investigation of his case.