He’s Got the Stars Sweatin’ : Tony Cortes is fast becoming Hollywood’s hottest fitness expert. His latest assignment?Shape up Val Kilmer for his Caped Crusader role in ‘Batman Forever.’

Linda Hamilton was transformed into a female Arnold for “Terminator 2: Judgement Day,” an out-of-shape Cher was chiseled into ageless perfection for her fitness video and Janet Jackson went from a bit chunky to a sexy video vixen.

All three women, at least in part, have fitness guru Tony Cortes to thank for their stunning definition, if not their talent. But does anybody actually care about yet another personal trainer to the stars?

Someone must. Cortes, 32, is fast becoming Hollywood’s hottest--if one of the unlikeliest--fitness guru.

Cortes, whose Specialized Exercise Training Systems is based in the un-Hollywood locale of Claremont, has also worked out with Priscilla Presley, John Malkovich, Johnny Depp, Valerie Bertinelli and Eddie Van Halen, Ray Liotta, John Cusack, Sugar Ray Leonard, Chris O’Donnell, Ron Perlman and Daphne Zuniga. But he is currently sweating it on the job for his most high-profile challenge to date: pumping Val Kilmer for his upcoming duties as the Caped Crusader in “Batman Forever.”

“With Val, we’re working on an endurance and a hypertrophy base,” Cortes says. “We’re trying to build mass. I hope to be there all the way through filming because it’s very important to Val, and to the production company, to keep him in good shape and from being injured.”

To that end, Cortes has been working for and with the actor daily for the past couple of months. Filming began in September. Along with the intense workouts, Cortes is also monitoring the actor’s eating habits. “We’re trying to fill him on a lot of complex carbohydrates and lean protein like cooked egg whites and chicken breasts, beans, rice, fish, raw and steamed vegetables. Nothing fried.”

On Kilmer’s forbidden list: pizza, red meat, cheese, processed bread, desserts and junk food. “He only gets a limited amount of coffee, and he can’t have milk in it,” he says, then relents. “OK, occasionally, maybe a little milk, but it has to be nonfat.”

Cortes prides himself on running a full-service fitness outfit. “If a movie company needs one of my clients to be trained for a fight on screen, I have someone who works for me that can do that,” he says. “If another client needs a bike made for his training, I can have it done for them. My job is to make it as easy for them as possible. But they have to be ready to work.” Dressed in loose-fitting sweats, Cortes is 5-foot-4 and an ironclad 145 pounds. He commutes to L.A.’s Westside from Claremont, where he also serves non-celebrity clients.

Cortes started in 1981 as a trainer in a small gym in Pasadena. His celebrity clientele built quickly after Hamilton selected him to prep her for “Terminator 2.”

“What we did with Linda was done in 13 weeks from scratch,” he says proudly. “We were looking at someone who really never exercised . . . who had just had a baby and, all of a sudden, she was in great shape. People were astonished.”

One way he achieves results is by tailoring the conditioning to the client’s needs. Music stars Janet Jackson and Eddie Van Halen, for instance, need a different type of program because of the intense workouts they already get on stage and in rehearsal.

“You look at exactly what they do and analyze it and say: ‘OK, this performer has to do a lot of heavy interval work with periods of high exertion, ups and down. They need strength and endurance.’ So we put a heart rate monitor on Janet, so that I (could read) her heart rate for every five seconds of her dance session.

“(With a film) we read the script and then meet with the director to determine just exactly what is going to be required. If you make an actor look great for a movie but then they have to do take after take of running and jumping and climbing, they’re gonna be dead. They’ll look sloppy because those demands require a different sort of training beyond just pumping up.”

Since January, Zuniga of “Melrose Place” has been working on aerobics, free weights and cardiovascular workouts with Cortes.

“Just like anything else in our lives, we’re moved by pleasure and deterred by pain,” Zuniga says. “Tony just understood that, and I was shockingly surprised. He wasn’t like a drill sergeant. I thought to myself, ‘How can this guy train Olympic athletes, and all these people I see look so great, and be so gentle?’ But with Tony, he helps you find your own strength; you work harder without beating yourself up. And I started to get results.”

Pumping up the stars has definitely kept things hopping at home. “One time, I was in the bathroom and my wife came in and said, ‘Honey. It’s Cher on the phone.’ I said, ‘Yeah, right.’ Then I realized she was serious and I came running out of the bathroom and grabbed the phone.”

All this attention doesn’t come cheap. “Usually, the celebrities make me a perk as a part of their contract,” he says. “But sometimes, it’s so important to the client that they have to pay it out of their own pockets”--pockets that can afford $400 to $600 a day, if Cortes goes on location with them for an extended period. That’s not including the per diem of $50 to $100.

For those regular Janes or Joes looking for a workout, the hourly rate is $90 per hour--a bit more if Cortes goes to your home, a bit less if you work with one of his associates. “We’re really affordable,” Cortes says. “Because what I think happens to people is that they go with a trainer who isn’t that good and they’ll blow 25, 30, 40, 50 dollars-an-hour, month after month, and never get anywhere. I have this attitude that you’re gonna pay me now--or you’re gonna pay me later!”

‘If you make an actor look great for a movie but then they have to do take after take of running and jumping and climbing, they’re gonna be dead. They’ll look sloppy because those demands require a different training beyond just pumping up.’ Tony Cortes