Athletes were tested for human growth hormone for the first time during the Athens Olympics, World Anti-Doping Agency chief Dick Pound said Friday.
While no positives have been reported, the samples will be retested to look for the muscle-building hormone and other previously undetectable drugs, Pound said.
"We're going to try to surprise some people with tests for the so-called designer drugs that are out there,' Pound said. "We think there may be some people who thought they had something that was undetectable but that now is.'
Pound estimated 300 samples _ around 10 percent of the total number of tests _ were screened for growth hormone at the Aug. 13-29 Games.
HGH, considered one of the most widely used banned substances in sports, works like an anabolic steroid, building muscle mass and helping athletes recover from training faster.
_ FRANK PASTOR, Times staff writer and TIMES WIRES