Andy Roddick's $10,000 NYC Marathon Bet

Justin Gimelstob (pictured right) doesn't have the right body type to run a marathon. Compared to the wispy, muscular athletes that he will toe the starting line with in New York City, Gimelstob is a behemoth. He's 6-foot 5-inches tall and weighs more than 200 pounds. He sweats prolifically. And, he'll freely admit, he's never been a runner. But he's also not a man to turn down a challenge.

As a professional tennis player, he spent years training to be among the world's best. His career-high No. 63 singles ranking and 13 doubles titles, made him a success by many standards, but hardly a household name. By the end of his 11-year career he had a herniated disc in his back, which was made worse by his aggressive tennis style that featured athletic dives and long-rallies. After 29 cortisone injections, he called it quits. He wanted to guarantee that he could have an active post-retirement life, and he feared more years on the tour would strip him of that freedom.

So why would the retired athlete, now living comfortably in California and working as a Tennis Channel commentator, plan to run the New York City marathon? And why, more importantly, would he subject himself to the agony of training -- running three days per week, biking, taking yoga class and completing Pilates?

It's easy: He has a bet to win against one of his best friends, staunchest supporters and, if he cannot complete the race, someone who will torment him unmercilessly for the rest of their lives -- Andy Roddick.

The story surrounding the bet is hazy, but the bet is crystal clear.

Gimelstob, a New Jersey native, said he has always wanted to run the New York City marathon. After a friend who was a runner passed away, he determined that this could be the ideal year to race. A non-runner running a marathon, he figured, would be the ultimate tribute. He mentioned the idea of running the race to Roddick who championed the idea.

"I think he thought about the amount of pain and agony that I would be in," Gimelstob said. "And, he wanted to make sure that he would be able to see me in as much physical pain as possible."

Gimelstob must run the marathon, a 26.2-mile race through New York's five boroughs, in four hours and 45 minutes. If he can't complete the race, he'll write a check to The Andy Roddick Foundation for education for $10,000. If he finishes the race in time, Roddick will hand over $10,000 for the Justin Gimelstob Children's Fund for children with cancer and blood diseases, which is linked to the Valerie Fund.

"I just thought that running the marathon was an interesting challenge both physically and mentally," Gimelstob said. "Combine that with the opportunity to raise money for the Justin Gimelstob Children's Fund, and there are very strong forms of motivation at work."

But will motivation alone be enough for Gimelstob to finish?

Even his father offered him $20,000 to scratch out of the race.

"As most people who know me are, he's concerned about my back," said Gimelstob. "Running is not something that I should be doing."

Working with trainers for the last several months to make sure he's prepared to run the distance without putting too much pressure on his back, Gimelstob runs just three times per week, choosing to focus on cross training and core-strengthening. On off days, he practice pain-reliving yoga and Pilates.

During the summer, he squeezed in workouts between tennis matches he a commented on, prompting Roddick to ask if he could double the bet while prompting others to ask if they could get a piece of the action.

"A lot of players have been very engaged in the bet, and they're all very supportive," Gimelstob said. "It's a fun source of entertainment. They'll ask me where I'm at or how I'm doing. Everyone has opinions."

Gimelstob, one of the more self-deprecating athletes on the tour during his tenure, realizes that he's taking a huge risk by entering the race. Although he's been an athlete his whole life, he's not sure how his body will respond.

"I don't know if I can do it," he said, shortly after a 14-mile run. "I'm training hard, and I'm a competitive guy, but this is unknown. I know I can play for hours and fight through five-set tennis matches, but this is a different kind of endurance."

Unlike in tennis, there are no breaks for changeovers, nor are there referees and umpires to argue with when something doesn't go quite right.

Luckily, the time limit isn't too imposing. He has to complete each mile in just under 11 minutes, and many celebrities have checked in under that time including Will Ferrell (3 hours, 56 minutes, 12 seconds), Oprah Winfrey (4:29.20) and Sean (Diddy) Combs (4:14.54). Gimelstob will also be able to rely on the members of the charity team he's formed to race with him and his East Coast-based family and friends.

"If I have to crawl across the finish line on my hands and knees, I will finish the race," Gimelstob said. "Nothing is more motivating than Andy being able to hold this against me for the rest of my life -- he's relentless."

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