ATHENS, Greece — Pole vaulter Toby Stevenson says it "amps" him up. Long jumper Grace Upshaw can "definitely feed off it." Swin Cash has never seen anything like it in the WNBA.

That flag-waving, wig-wearing, anthem-singing Olympics crowd hasn't done the U.S. men's basketball team many favors, but the fans in the stands are getting most of America's other athletes in Athens positively pumped.

"You know what? It's incredible when you've got 80,000 people screaming at you from all sides," said Stevenson, of Chula Vista, Calif. "I feed off the crowd, and when I'm playing to 80,000 people, it just amps me up even more."

Greek athletes, naturally, are getting the most muscle out of the unabashedly partisan crowds, which started small but have swelled at many venues into the real deal.

Booing, whistling and chanting delayed the start of Thursday night's 200-meter final by four minutes as Greek fans vented frustration at the absence of Kostas Kenteris, the defending Olympic champion who withdrew from the games after missing a drug test.

Americans Shawn Crawford, Bernard Williams and Justin Gatlin, who swept the medals, got the business end of the rowdy crowd: Its jeers were loudest when they were introduced, though there was plenty of applause as they crossed the finish line.

But the roar at Olympic Stadium was like rocket fuel on Wednesday for Greek hurdler Fani Halkia, who pulled off an upset win to take gold in the 400-meter hurdles.

"What happened in the venue is beyond words. It was like an earthquake," she said.

"The crowd was amazing from the get-go, and the atmosphere they created was unprecedented for me. That gave me incredible energy."

Jonathan Johnson, a middle-distance star from Texas Tech, couldn't believe the scene during an 800-meter heat. "I've never seen a stadium so crowded," he said.

It gave Tim Mack goose bumps. "When the crowd was going nuts, I told myself we're finally at the biggest stage you can get," he said.

Upshaw, who made it into the long jump final, said she uses the crowd "to keep me up in the game."

"It doesn't intimidate me at all, and I can definitely feed off it," she said.

It can be a psych-out, though — especially if your opponents happen to be Greeks.

Sue Bird, who helped lift the U.S. basketball team to a 102-72 victory over Greece, said the atmosphere was "definitely different" from what she's used to.

"It is much bigger and a lot more people," she said. "It was a really tough environment, and it was also a challenge for us to keep the crowd quiet. We didn't want them to get into it."