It all started with a pizza. In 1989, David Clark's law school buddy bet him a pie he couldn't run the Chicago Marathon. Clark took him upon it.

"It was Gino's East, c'mon," he said.

Clark finished that first race and never looked back. Now 41, the Wheaton man is staring down his 50th marathon in 50 states, though in all he's run about 109 marathons and ultramarathons, a designation for any race that exceeds 26 miles. The final challenge lies in Myrtle Beach, S.C., on Saturday, Feb. 16.

"Most us of us, we work at our desks," said Clark, an attorney with the Wheaton-based law firm Peregrine, Stime, Newman, Ritzman & Bruckner Ltd. and co-owner of Dick Pond Athletics in Carpentersville. "What real challenges do we have in our lives? (Marathon running) is one challenge you really have to work for."

The accomplishment will qualify Clark for induction as a "finisher" into the 50 States Marathon Club based out of Houston. The organization has nearly 1,500 members in all 50 states, Washington, D.C., and nine foreign countries, and runners may join if they're completed 10 marathons in 10 different states.

"The 50 state marathon group is a very tight group," Clark said. "The median age of club members is 55. I've never seen a more fit group of people in AARP in my life. Some of them have run a marathon in each state five or six times."

Few can understand this sort of drive and as a full-time professional and father of two, Clark admits it has been far from easy to get where he is today.

"I couldn't have done it without my wife (Rebecca)," he said. "Any runner couldn't go out and enjoy themselves without support."

And family support has become something of a shared passion. At 7, Clark's daughter, Annika, has already participated in some local one-mile races and 12-year-old son Graham, a member of the track team at Wheaton Christian Grammar School, is a two-time triathlete.

After getting the OK from an orthopedist, Clark agreed to his son's request that he run his first marathon in South Carolina.

"I'm very excited about it," Clark said. "I'm almost more excited about it than I am about finishing."

"I like to do long distance events," added Graham, who said he felt ready for the challenge.

Despite a persistent back injury, Clark runs every other day, pounding the trails at places like Blackwell Forest Preserve and the Morton Arboretum. While the prairie state offers little in the way of peaks and valleys, local paths have managed to provide him with training grounds for races out west.

"Both sides of the Arboretum have a fair amount of hills," Clark said. "Now is that going to mimic the 9,000 feet in Utah, Colorado and Wyoming? No, but the only thing you can do is make sure you have your base miles in."

He has seen and experienced a lot in the last decade or so. The natural beauty of Maui, Hawaii, and Anchorage, Alaska, and the good people of Cincinnati, Ohio. But Clark's favorite race would probably be the little-known Ridge Runner marathon in Cairo, W. Va., one of the oldest competitions in the country.

"I received such a nice welcome and the scenery in the Appalachians is just amazing," he said.

Clark is admittedly not the fastest of marathon runners — he averages between four and a half and five and a half hours —  but over the years he has learned a thing or two about his body and its abilities.

"I wouldn't go so far as to call it an art, but it has taken me years to learn a pace," he said. "For someone who's never run a marathon, I say give it a shot. You don't have to be super speedy."

Jay Jackson of St. Charles, co-owner of Dick Pond athletic gear store, tips his hat to all his friend of seven years has managed to achieve.

"It is very, very difficult to get all those long runs in and still work 50 or 60 hours a week," Jackson said. "I know he has to get up and go real early in the morning or go on his lunch hour. He's incredibly dedicated to what he's trying to accomplish."

For more information on the 50 States Marathon Club, visit www.50statesmarathonclub.com.

Online Videos by Veoh.com