Sato acknowledged he was probably the only Olympian with such a profession, but said the discipline of his day job — he sometimes spends 19 hours a day sitting and meditating — helps him while he's riding.
"Before the competition starts, I concentrate. I'm behaving more like a monk," he said.
U.S. swimmer Tyler Clary went back to work as soon as he won a gold medal and set an Olympic record in the 200-meter backstroke. He's an accomplished DJ, and headlined at a London club called Chinawhite last weekend — though he said the gig wasn't so much work as "part of the celebration."
But of all the extracurricular jobs among the 2012 crop of Olympians, perhaps Logan Campbell's raised the most eyebrows. The New Zealand taekwondo fighter opened a high-end brothel in 2009 in Auckland to finance his training and travel schedule ahead of the Olympics, so his family wouldn't have to bear the burden. Prostitution is legal in New Zealand.
"At the time, taekwondo wasn't getting any funding at all," Campbell said earlier this year. "So it was pretty much to get good at the sport, you had to get international competition, and there wasn't any funding for us."
Campbell, who competes Thursday, sold the brothel in 2010 after he was criticized by Taekwondo New Zealand and the national Olympic committee — and, more importantly, after sponsors started funding the sport.
Usain Bolt has his own bar in Kingston, Jamaica — a restaurant-sports bar/night club called Tracks and Records, which aside from mixed drinks sells Usain Bolt merchandise. He, like Phelps, has made an industry out of his own brand.
Phelps started early, when he signed a sponsorship agreement with Speedo in 2001. Now he makes $5 million to $10 million a year. After the 2008 Beijing Olympics, where Phelps won eight gold medals, his agent, Peter Carlisle, predicted Phelps would make $100 million over his lifetime.
The aim of the sponsorship deals, Carlisle said in an interview, was to create a Michael Phelps brand that would carry him through the four-year lulls between Olympic games — and beyond.
Phelps returned the favor Sunday, his first official day of retirement after becoming the most decorated Olympian of all time.
He likened sponsor support to having "a family away from home" and said it gave him "the freedom to train 100 percent and focus on what I needed to do. That's something I've been very fortunate to have."
He said it at a press event sponsored by Visa.
Associated Press reporters Paul Newberry, Beth Harris, Shawn Pogatchnik, Tim Reynolds, Dave Skretta, Pat Graham and others contributed.
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