One hefty young fellow came through the gate with two burglary convictions and the title of "biggest screw-up in Dublin, Ga." He lost 66 pounds in 90 days here at Dodge Correctional Institute -- and he was not on a diet.

Barely men yet, the fledgling convicts arrive out of shape, cocky and thinking they can handle this program the way they have handled their previous run-ins with the law, says warden Robert Lavoie.

Then they spend three months in shock incarceration.

Dodge is a new sprawl of low, slant-roofed buildings liberally ringed with razor wire, set in an expanse of flat, sunbaked farm land about a three hours' drive south of Atlanta.

It is a state prison with a special sideline: to give convicted felons between the ages of 17 and 25 a "short, intense" taste of prison life without its permanent scars, enough to discourage them from risking a return engagement.

Under a military-style regimen and sporting Marine head shaves, inmates rise at 5:30 a.m. for chow and march out to do the most backbreaking work prison authorities can dream up.

Their blue-uniformed guards are all former military personnel. Armed with pistols and shotguns, they call out the cadence of the "Dodge Shuffle," the inmates' military march. Shouldering hoes, axes and sling blades like weapons, the inmates parade out to the blistering fields where they pick okra and butter beans for the prison kitchen or to the roadside to trim weeds or to the forest around the prison.

There they clear stumps, digging holes deeper than the inmates are tall and wrenching up the centuries-old tap roots. No power mowers or chain saws allowed.

That is from dawn to 3:30 p.m. Then they march back to the gym for calisthenics.

The shock incarceration inmates are separated from the hard-timers in the prison by a fence through the prison yard. The regular inmates call out ("Hey, Sugar Britches! Hey, Fresh Meat!") to the young ones, hinting unmistakably at what will happen if they return for real.

"I want to carry them right to the brink of hell for 90 days," said warden Lavoie, gesturing toward the regular inmates. "Hell's over there on the other side."

The young inmates say it is effective.

"They're sure here to scare you," said K.L. Mixon, 21, a youth with an all-American appearance. Eyeing a guard, he stood at attention for a visitor to his spartan quarters. He had stolen a three-wheeler in Waycross and, he added, "had a bad attitude." He said his attitude has improved, and he never wants to return to this place.

Only those who have never served time in an adult prison are eligible for shock incarceration. But those who participate, Lavoie said, "have probably been a thorn in some judge's side" for a long time. "The judges claim they don't recognize them when they come back."

Once released, the young felons return to probation for the rest of their terms, often to intensive probation supervision. They are sent on their way with $25, a suit of clothes and a bus ticket home.

Shock incarceration -- known officially as Special Alternative Incarceration -- costs slightly more than regular imprisonment because of the extra supervision, Lavoie said. But its targets otherwise would have been locked up for five years while the state supported them and probably their families, he said.

If the participants misbehave, officials can petition the court to revoke their probation and put them on the other side of the fence.

Shock incarceration has exceeded its original expectations, which were low because similar programs have not worked well, officials said.

The most famous of the others, featured in an Oscar-winning film called "Scared Straight," is the Lifers Juvenile Awareness Program at Rahway State Prison in New Jersey. It brings youngsters from the community into the prison briefly for a show-and-tell by the inmates.

The Rahway program did not live up to its billing, according to Dr. James Finckenauer, professor of criminal justice at Rutgers University. His research, sponsored by the state corrections department, raised "at least the suggestion that the program actually stimulated delinquency" in young people, he said.

New Jersey officials remain supportive of the program, said a state spokesman who added that another study showed it to be effective if it is followed up properly in the communities.

Lavoie said Rahway inmates were allowed too much control over the "Scared Straight" program. "Here, we don't let the inmates run anything," he said.

Of 439 who have passed through shock incarceration, 11 have failed during the program and 16 have committed new crimes later.

The Dublin screw-up, newly lean, is home again, working for a construction company. Said Dodge official Michael Taylor, "He's working and behaving himself, got a little girlfriend and he's doing all right."