PEMBROKE, Mass. -- It may not be Muhammad Ali versus Joe Frazier or Mike Tyson against Evander Holyfield, but the two opponents in a heavyweight battle said they are duking it out to be the champ.

NewsCenter 5's Heather Unruh reported that the competitors, P.J. Lowe and Dan Vail, are fighting for weight loss and better health.

Lowe has lost at least 40 pounds in the past two months. More importantly, he's made lifestyle changes by adding breakfast, dropping late-night fast food and drinking less beer.

Lowe and Vail are in a 90-day competition to see who can lose the highest percentage of body fat.

"We're constantly, 'How do you feel?' 'Did you go today?' If you woofed down a cheeseburger, it's a good support system," Lowe said.

The men are both small business owners and have found a lot of local support from the Pembroke Chamber of Commerce.

"They're helping me move a mountain I couldn't do myself," Vail said. "We're all winning."

Their workout styles are different: Vail said he prefers Kempo Karate to a traditional gym.

"I never in my wildest dreams imagined I could survive half of one of these classes. I was 305 pounds the first time I walked in here. This is a joke, I'll come in here, collapse, they'll carry me out of here in an ambulance. That will be it, you know?" he said.

So far, Vail's lost about 30 pounds -- with no ambulance rides.

The heavyweights said you can't let large size keep you out of the gym.

"You don't have to be perfect. You don't have to be beautiful to get started. You can come in as you are, do your best," Vail said.

The contest is helping raise money for a local scholarship fund. It ends in less than a month, but Lowe and Vail said they are in it for the long haul.