Dennis, 35, of Gloucester Township, and Rosenberg, 30, from Collingswood, are ultrarunners. They push themselves through grueling training regimens to prepare for the rough terrain and brutal weather that can accompany races of 100 miles or more.

They manage to balance training and competition with successful careers, and in Dennis' case, marriage and parenthood. He has an 18-month-old daughter and expects a son within a month.

"A long race for me is more about the adventure than the end result of finishing," Dennis said. "It's hard to put into words how you feel when you finish something like that."

According to Dennis, who has a law degree from Temple University, and Rosenberg, who got his degree from Rutgers-Camden Law School, ultrarunning races typically exceed marathon distance. They range in length up to 200 miles. The two have yet to run a 200-mile race but they competed in eight races this year, leading up to the Mohican Trail 100 Mile Run, held in Loudonville, Ohio, June 21-22.

During races such as the Mohican 100, runners tackle some of nature's toughest terrain. They're often required to cross rivers or scale rock faces. A 24-hour race also introduces the problem of running in total darkness. And there's the weather to contend with - driving rain, chilling cold and sometimes deep mud.

"It's not just running these races. It's surviving them," Rosenberg said.

An ultrarun is not something someone just walks into. In order to survive these races, Dennis and Rosenberg spend months preparing their bodies for punishment. On a typical workday, Dennis and Rosenberg will split their daily training regimen in half, with a morning run as early as 3:30 a.m. and a second after work. They reserve marathon-length runs for the weekends.

"For ultrarunning, the key is, you're on your feet for so long your body just breaks down," Rosenberg said. He said the key to preventing the breakdown is cross-training, which gets the entire body "universally strong."

The two are now in what they call an ultrarunning off-season, but they plan to run in the 10 kilometer McGuire Mud Run on Nov. 8.

The two runners have incorporated strength- and agility-boosting exercises, yoga, swimming and, for Rosenberg, games of hockey.

"When it comes down to running, we don't break down nearly as quickly, because every aspect of our bodies is in good shape," Rosenberg said.

Dennis and Rosenberg are able to balance the demands of family, career and training, according to one of their supervisors, Raymond E. Milavsky, first assistant prosecutor of Burlington County. Milavsky, also a runner, said he supports and applauds both their work and recreational activities.

"What I see with these two particular attorneys is they bring that same degree of commitment and intensity to their work," Milavsky said. "It's an accomplishment that very few people can ever say they did, and they bring that discipline and intensity to work every day."

Dennis said he has managed to incorporate his daughter, Haley, into his training routines; on weekends, his wife, Julie, and daughter will sometimes ride a bicycle alongside him as he runs. He also said that occasionally he'll take his daughter out in a jogging stroller, or in a lightweight backpack for trail running.

Judging by the amount of juggling Dennis and Rosenberg have to do to accommodate their training, it might seem like ultrarunning only creates added stress. The sport itself is extreme in nature. Dennis explained that in the longer races, at some point, the actual mileage remaining in a race becomes secondary to the mental struggle to keep moving. They said they thrive off of overcoming the challenges.

"It only goes to show you, you really can do whatever you want to do," Rosenberg said. "It's like turning the volume down on everything else."

Dennis explained that he has found camaraderie in the sport. He said competitors constantly encourage others during the race, even when passing each other.

"When you run the long races, you'll inevitably hit a wall," Dennis said. "It's easier to get through that when you have someone else being there with you."