Tyson Gay suspended 1 year, returns Olympic silver medal

Aug. 11, 2012: Tyson Gay celebrates after receiving the silver medal for the men's 4x100-meter race during the athletics competition in the Olympic Stadium at the 2012 Summer Olympics, London. (AP)

Sprinter Tyson Gay has accepted a one-year suspension and has returned the silver medal he won in the men's 400-meter relay at the London Olympics after he tested positive for a prohibited substance.

USADA announced Friday that Gay's one-year ban began last June 23, the day his sample was collected at the U.S. championships.

As part of the penalty, he also accepted loss of results dating to July 15, 2012.

USADA said in a statement that upon receiving notification of his positive tests, Gay voluntarily withdrew from all competition prior to the 2013 world championships and has not competed since.