After years of getting on the treadmill at air-conditioned health clubs, more and more people are flocking to warehouses to break a sweat.

"We have a woman who's lost 85 pounds working out with us. She's just a regular mom. She's not any world-class athlete," said Elite Crossfit owner Jeremy Tucker.

Even after dropping six pant sizes, Katy Stephens remembers her first day at Crossfit.

"I really felt like a beached whale on the floor," Stephens said.

Stephens admits the program is intense but says the coaches modify it to accommodate various fitness levels.

Behind the warehouse door, you see weights, tires, jump ropes, bars and very little else. It is a bare bones gym with familiar equipment, but the workouts themselves are very intense.

"Well the programming, we want everyone doing the same thing exactly the way we want and going back to the form, if it's not done correctly, we're not going to allow them to put more weight on," Tucker said.

Nancy Antcliff is another newcomer to Crossfit who says it has changed her life.

"Eight months later by the grace of God, I've dropped 45 pounds and I have lost 7 inches off my waist. Everything else has moved also," Antcliff said.

Dr. Gregory Ernst thinks Crossfit is a great program, but it may not be for everyone.

"The best exercise for a person is going to be one that they're going to keep up with, but that's the disadvantage of Crossfit too. For someone not accustomed to exercise, the high intensity of the program may make it seem to difficult for them," Ernst said.

It is a fitness regimen that caters to world class athletes, but owner Jeremy Tucker enjoys using it to make extraordinary changes in the lives of ordinary people.