Helio Castroneves Helio Castroneves

Two-time Indy 500 winner Helio Castroneves was less than four hours away from this year's big race when he had a conversation with a stranger that he'd remember forever: Dancing with the Stars' fourth-season champ, Apolo Anton Ohno, had shown up at the track. "I congratulated him on his [Olympic] gold medal and on winning Dancing with the Stars," says the Brazilian-born Castroneves, 32. "And then I said, 'How was that? It seemed like it was really fun.' And he said, 'Oh, man, it was a lot of hard work, but it was great.' And then he said, 'Why don't you do it?'"

This was at 8:30 in the morning on May 28. The race was set to start at noon. Castroneves turned to Ohno and said, "Can I talk to you later? I'm about to race 500 miles."

As it turned out, Castroneves did not repeat his 2001 and 2002 wins. But he did follow through on his conversation with Ohno and immediately said "yes" when the Dancing producers came calling. "Apolo spoke to them," says Castroneves. "So it was smooth."

Then came the next lightning bolt: His partner would be none other than Julianne Hough, who took Ohno all the way to the disco-ball trophy. "I don't think Apolo did that," says Castroneves, laughing. But when Castroneves first saw her, he says, he thought, "Whoa, I got the champion!" And then he thought, "Hold on, that's a lot of pressure. If I don't win, it won't be her fault."

Castroneves is trying to make sure it isn't his fault, either. He knows what it takes to be a serious dancer. His older sister, Kati, who is now his business manager, was a professional ballerina in Sao Paulo and danced for 20 years. "She said, 'You're going to be using muscles you never knew you had.' And I never believed it. But now I do."

The problem, according to Castroneves, is that when you're sitting in a race car, you're not really using your legs. "I hate doing squats," he says. "I always told my [racing] trainer that we don't use legs that much [to get out of doing squats]. And I'm regretting it now because most of the moves in dancing use squatting and then you're up on tippy toes. I had no clue."

But even if his body isn't fully cooperating, Hough, he says, is trying to put his new routines into language he can easily understand. "She'll say, 'Listen, imagine you're a car, going smooth, up and down.'" Castroneves is fine with letting her take the wheel. "She said, 'I'm going to try to do everything that I did last year, because it works.'" Then he mentally crosses his fingers. "I won back-to-back Indianapolis 500 races. Maybe it's a sign to give Julianne back-to-back wins."

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