The newest way to slim down inside the Beltway: hire a military-type drill instructor to bark at you.

Bill Edelblut, 45, is no craggy faced jarhead, no grunt, no dogface. Yet here he stands before his drill instructor in the dawn's early light: I cannot tell a lie, sergeant, sir, " Edelblut solemnly confesses. "I did eat a Big Mac."

Edelblut, owner of O'Donnell's restaurant in the Washington, D.C., suburb of Bethesda, endures a few moments of colorful cussing and then joins his platoon in an hour of training: charging up hills, doing pullups on branches, scrambling over boulders, pumping bricks, lugging logs.

This isn't boot camp: Edelblut and company have paid for this abuse by enlisting in the Sergeant's Program, a workout regimen that challenges Washingtonians to be all they used to be. Its driving force, Patrick Avon, (pictured to the right drilling a program member) is a former Navy fitness instructor who describes himself as "Richard Simmons' evil twin."

In a town that already boasts more than its share of gyms for the district's overworked and overfed, the Sergeant's Program is nothing fancy: just five mornings of inventive aerobic, belly-flattening workouts, led by highly motivated instructors, more than half of whom have mili-tary backgrounds. Workouts start at 6 A.M. rain or shine, in the many parks around the nation's capital.

The way Avon describes the program is characteristic: "no music, no dancing, no mirrors, no spandex, no crybabies, no refunds."

You start by shelling out nearly $345 for four weeks of "boot camp" to become fit enough for everyday participation, and 80 bucks a month for the daily maintenance workouts.

Edelblut calls the program "The best thing I ever did for myself. I've lost 30 pounds, and several inches around my waist. I also don't have the stress I used to have. It really clears my head."