Gold medalist Dan O'Brien is competing in the decathlon again.

Well, not the decathlon. He won Olympic gold in that event at the 1996 Atlanta Games, and at age 46, he is now a little past his prime. But he will compete in a decathlon. To be specific, he's competing in this summer's RBC Decathlon, the annual charity competition among Wall Street employees that benefits the Sloan Kettering Cancer Center.

So how does an Olympic gold medalist feel about competing against stock advisors, hedge fund managers and other Wall Street employees?

"I'm sure that once I get close to the competition, I'll feel nervous because you're pushing yourself," O'Brien said. "That's what I like about the event. It's the challenge. It gives everyone a long-term goal. When you train for the Olympics, that's all you can do. You can't go to work, you can't have a part-time job. But these guys are doing it on the side. ...

[+] Enlarge

Kirby Lee/USA TODAY SportsDan O'Brien will compete in the one-day RBC Decathlon on July 27 at Wien Field on the Columbia University campus.

"I don't take anything lightly. If I'm going to compete, I'm going to take it seriously. As an athlete, you don't want to underperform."

Donations are raised through CharityBets, a performance-based fundraising program developed by RBC Decathlon organizers Dave Maloney and Marc Hodulich. The concept is simple. You can either make a simple set donation or make a sliding donation based on the performance of the competitor on whom you bet. The good thing is, regardless of how your bets goes, charity always wins.

"I've been known to gamble a bit from time to time," O'Brien said of the event's appeal. "The program he's developed makes sense to me. It's a good fit for these guys. They are guys with disposable income, they're mature and well-muscled. They're doing it for the fun of it, but they're also doing it for the charity. I'm honored that Dave would want me to be the face of the decathlon."

"Dan's participation opens up a world of charity-betting possibilities and will dramatically increase spectators who take a keen interest in his performance," Maloney said. "He's also still a role model to much of the financial services community, so Dan's presence will certainly stoke the competitive spirit among participants."

The Olympic decathlon takes place over two days, while the RBC Decathlon is a one-day competition at Wien Field on the Columbia University campus July 27. The RBC Decathlon is a combination of an actual decathlon and a football combine. The 10 events are the 400-meter run, football throw, dips, 40-yard dash, 500-meter stationary row, five-cone drill, pull-ups, vertical jump, bench press and 800-meter run.

O'Brien said he is confident he can hold his own in the pull-up and vertical jump competitions, but he expressed concern about the 400 and 800 runs. One, some back pain issues have restricted his running in recent years, and two, everyone hates the 400- and 800-meter lengths.

"Even as a former athlete, those are two events you don't want to do," he said. "Put me in a 5K or let me run a 40, but don't put me in the middle-distance races. To run a good 400 or a good 800, you have to train."

Not that O'Brien ever minds that; in fact, he said he preferred training to competing.

"Ultimately, what it came down to was that I loved my job," he said. "I liked getting up every day and working toward my goal."

For more information about the RBC Decathlon and this year's inaugural Wall Street mile run, go to thedecathlon.org.

Unlike most of the distance runners who traveled to New York last week, marathoner Desiree Davila arrived knowing she wouldn't be hitting the famous 26.2-mile course.

Davila has been off her feet almost entirely since Aug. 5, when a mysterious and painful hip injury forced her out of the Olympic marathon in London after just one 2.2-mile lap. Composed but obviously devastated, she told reporters she had done everything possible to get to the start, including training on a special high-tech treadmill that minimizes impact and taking a cortisone shot. She hoped for a miracle, but it wasn't to be, so she crossed the finish line on The Mall 24 miles early and walked away from the race she'd spent four years visualizing.

Back home, a detailed MRI showed what had been missed in an initial diagnosis -- Davila had a stress fracture at the top of her right femoral shaft. She rested completely for eight weeks, then began some stationary bike work and only started running again about two weeks ago, for 10 minutes at a time. That puts her, in her words, at the bottom of the family mileage board below her fiancé Ryan Linden and their two dogs.

It's by far the longest layoff of a goal-oriented life, so how is Davila dealing with the unaccustomed inactivity? "You can ask the people around me," she said with a throaty laugh over the phone from New York City, where she was fulfilling sponsor obligations. "I think I needed it. I was so frustrated and beaten down by trying to get through the whole process. Now I'm itching to go."

Davila doesn't regret her decision to give London a try; she said she acted based on the best information she had at the time. "If it had been diagnosed right, I wouldn't have been there, and I wouldn't have tried to train to get there," she said. She's still unsure about when she'll race again. The imbalances created by months of favoring her right hip need to be addressed with soft tissue work and physical therapy.

For now, the Boston Marathon -- where she set an American course record in 2011 -- remains on her schedule (the race is on April 15), "and we'll keep it on until we know it can't work," said Davila, who trains in suburban Detroit with the Hansons-Brooks Distance Project. "Things would have to be pretty perfect in January for that to happen."