Updated

Former elite cyclist Tammy Thomas pleaded not guilty in federal court Friday to charges of lying to a grand jury investigating steroid use in sports.

Thomas, the first athlete charged in a probe that has implicated some of the biggest stars in baseball and track and field, is charged with three counts of perjury and one count of obstruction of justice.

Thomas, who appeared much slimmer than during her racing days, declined comment after being released on $50,000 bond.

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Thomas was banned from cycling for life in August 2002 after testing positive for the performance-enhancing drug Norbolethone, which was detected in her urine samples.

The drug, once an obscure steroid used in human tests in the 1960s, was rediscovered by chemist Patrick Arnold, who supplied the Bay Area Laboratory Co-Operative with undetectable performance-enhancing drugs and is among five people who have pleaded guilty in the investigation.

Thomas was a silver medalist in the individual sprint at the 2001 World Track Cycling Championships. She has maintained her innocence and said the positive results might have been triggered by contraceptives she was using.

The indictment accuses Thomas of lying when she testified to a grand jury that she never used performance-enhancing drugs. She also is said to have lied when she testified that she did not get illegal drugs from Arnold, who pleaded guilty last year and was sentenced to three months in prison.

Each count against Thomas carries a maximum five-year prison term and $250,000 fine. No trial date was immediately set.

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