CRUNCH TIME : WHEN CELEBS NEED TO SHAPE UP, PERSONAL TRAINERS ANSWER THE CALL.

Byline: Jenifer Hanrahan Daily News Staff Writer

Michelle Pfeiffer went from skinny to sculpted.

Angela Bassett's biceps soon bulged.

Kathy Ireland transformed her post-pregnancy belly into a smooth and sinewy stomach fit for workout videos.

Think they achieved those flawless forms by taking the stairs or joining the local gym?

Heck, no. These three women owe their beautiful bods to celebrity trainers.

Hollywood's personal trainers custom-design weight programs and cardiovascular workouts for star clients who can afford the pricey service. Personal trainers also refer their clients to personal chefs, massage therapists and acupuncturists.

Such star treatment doesn't come cheap: Personal trainers fetch anywhere from $60 to $175 an hour for their expertise.

But when the camera comes in for a close-up, it's well worth the price.

``They're being watched. Because of their job, the results are more visible, so it motivates them,'' said Karen Voight, a premier Los Angeles personal trainer and star of eight fitness videos.

Here's the skinny on some of Hollywood's top celebrity trainers and their rather famous accomplishments:

When Ireland wanted to get back her million-dollar body after giving birth to her first child, she tapped Tim Green, a Los Angeles-based trainer whose first claim to fame was toning Richard Simmons.

Dieting wasn't an option because the supermodel, best known for the Sports Illustrated swimsuit issues, was breast-feeding. Instead, Green had Ireland working out five days a week, 2-1/2 hours a day for six months.

The result? Ireland dropped 40 pounds and several inches off her hips, thanks to a program that included a 15-minute warm-up and an hour of high-intensity cardiovascular exercises such as running, jumping rope and aerobics.

To keep it fun, Green and Ireland occasionally played volleyball or badminton, ``anything that could keep us moving,'' he said.

As if that wasn't enough to keep her sweating, Ireland also toned and defined the muscles in her chest, back, arms, legs, stomach and shoulders through calisthenics and weight-training. Each workout culminated with 15 minutes of stretching.

Ireland even came out with her first fitness video, ``Total Fitness Workout.''

Green, owner of Masters in Motion in West Hollywood, said Ireland is one of his proudest makeovers - especially since the model went from struggling with five push-ups to cruising through 50.

But he can't promise that everyone who follows his intense program will look like Ireland.

``A lot of people hire us and say, `I want to look like that.' But what worked on her isn't necessarily going to work on everyone. Everybody's metabolism is different. Their muscle structures are different. Their genetic structures are different,'' said Green, whose famous clientele also has included Paula Abdul and Richard Dean Anderson (``MacGyver'').

There's no denying the demands of the tight, vinyl cat suit Michelle Pfeiffer wore in ``Batman Returns.''

To make sure it fit, Pfeiffer turned to Kathy Kaehler, a West Hollywood personal trainer who does a biweekly fitness spot on NBC's ``Today.'' The owner of Muscle Under personal training gym has appeared in several fitness videos and maintains a celebrity client roster that includes Penelope Ann Miller, Jennifer Aniston, Ellen DeGeneres, Jamie Gertz and Julianne Phillips.

The intense filming schedule for ``Batman'' only left room for an early workout. So every morning at 4:30 a.m., Pfeiffer and Kaehler did workouts that included 50 minutes of step aerobics while holding 2-pound weights, plus exercises to increase the actress's muscle definition.

Pfeiffer also performed abdominal crunches to firm her tummy. She could only complete 20 at first, but was performing three sets of 30 in no time.

No longer playing roles in body-hugging cat suits, Pfeiffer still works out with Kaehler six days a week. They Rollerblade, run three to four miles, or jump rope for the aerobic portion of the workout, and finish up with weight training and stretching.

When Pfeiffer first started working out, ``she was just thin,'' Kaehler said. ``Now she looks like she exercises.''

Kaehler has trained her share of Hollywood men, as well. Two years ago, Tom Arnold called upon Kaehler to help him shed some pounds. For three months, they did 45 minutes of step aerobics three times a week, and hiked four or five miles on alternate days. Another trainer helped the co-star of ``True Lies'' with weight-training, while a personal chef cooked him healthy meals.

In the end, Arnold lost more than 50 pounds. The former husband of Roseanne is now remarried and set to star in ``The Stupids'' in May.

``I saw him lose body fat,'' Kaehler said. ``He looked trim.''

Kaehler is pregnant with twins and will have to slow her schedule in the next few months. Afterward, she plans to develop a workout tape for getting back into shape post-partum.

``They told me I need a period in the day where I am lying down, which is hard for me,'' she said.

Behind Angela Bassett's bulging biceps in the 1993 movie ``What's Love Got to Do With It'' was personal trainer David Sinnott, a former bodybuilder who transformed his own physique from a pudgy 250 to a muscular 175 pounds.

It took only one month of two-hour training sessions at Gold's Gym in North Hollywood to transform Bassett into looking like muscular r&b-rock diva Tina Turner - the subject of the biographical movie.

Weight-training techniques like lifting 15-pound dumbbells to define the arm muscles were valuable, but a change in Bassett's diet was key in achieving a well-sculpted body, Sinnott said.

Bassett was told to stay away from processed diet foods and switch to unprocessed complex carbohydrates like baked potatoes, brown rice and whole grains. She also loaded up on fruits, vegetables and protein-rich chicken and fish.

``Most people think about training harder and longer,'' said Sinnott, who also worked with Bassett on ``Strange Days.'' ``If that worked, then wouldn't everyone who goes to a gym be looking great? It's mostly about diet.''

Though no longer working out with Sinnott, Bassett could still be found showing off her firm physique in last year's ``Waiting to Exhale.''

``She has a beautiful body,'' Sinnott said. ``She just exudes poise and grace. She has the total package.''

Sinnott has no formal fitness training, calling his ``practical experience.'' As a bodybuilder, Sinnott had a thick layer of fat covering his muscle. By changing his eating habits, the Los Angeles man lost the excess fat but kept the muscle. He perfected his weight-lifting technique, and cut down his workout from three hours a day to a couple of hours a week.

``What I accomplished for Angela is a version of what I accomplished for myself,'' said Sinnott, who just released three videos called ``Lean at Last.'' He also makes a lucrative living training less-famous folks in L.A. ``I used myself as a human experiment,'' he said.

While Bassett was pumping iron to bulk up her big-screen image, the real Tina Turner was walking and dieting her way to a slimmer body for her 1994 tour.

The electrifying singer sought the help of Voight, who authored ``Precision Training for the Body and Mind'' and teaches aerobics at Voight by the Sea exercise studio in Santa Monica and a spinning class, an intense workout on a stationary bike, at World Gym in Santa Monica.

Turner burned fat by working out up to 1-1/2 hours a day, five days a week. She walked for 45 minutes on the treadmill (at a speed of 4 mph on an 8 percent incline), followed by 15 to 45 minutes of weight training, abdominal crunches and stretching.

``Her body looks similar to my students who are 25 years old,'' Voight said. ``She has defined muscles and no body fat, and she's got great proportions.''

Turner shaped and defined the back of her buttocks and killer thighs using 5-pound ankle weights to do several types of leg-lifts. While holding on to a chair, Turner repeatedly raised her heel to her buttocks. Next, she bent her knee and repeatedly pushed her leg back.

Working at a low intensity for a long time helped Turner lose weight. That, plus a diet that was low in fat and high in complex carbohydrates.

``Moderation and consistency are the two keys,'' said Voight.

Voight also trained Elle Macpherson for her video, ``Your Personal Best Workout,'' released last year. Macpherson lost the 20 pounds she gained for her role in 1994's ``Sirens'' by sweating it away during one-hour sessions three days a week for three months.

Macpherson combined low-impact aerobics with weight training to regain her supermodel body. Holding 5-pound weights, Macpherson bent at the waist and repeatedly extended her arms behind her to define her triceps.

``She's really thin. But she has firmness and she's well-defined,'' Voight said.

Demi Moore's body is fast becoming the stuff of Hollywood legend. Todd Person was happy to help.

The owner of Metabolic Project, a personal training gym in West Los Angeles, Person was tapped by the hard-bodied megastar to tone up an already muscular frame. She trained with Person four days a week for 1-1/4 hours per workout - 40 minutes of running or fast walking on a treadmill, followed by 35 minutes of body-sculpting exercises.

Plies (the ballet move) toned her inner thighs and buttocks. With her feet apart and toes pointed out, Moore held a 45-pound dumbbell and bent her knees until they were almost parallel to the floor.

She repeated that 50 times.

``Most women would kill for her body,'' said Person, who also has trained Bruce Willis, Rachel Hunter, Jeanne Tripplehorn, Jon Bon Jovi and Michael Keaton. ``This girl is in serious shape.''

Christian Slater sought Person's help in beefing up his arms and chest for the action movie ``Broken Arrow,'' which co-starred John Travolta.

In hourlong workouts five days a week, Slater lifted a series of weights 12 times - or until his muscles gave out. If Slater finished the repetitions, Person increased the weight for the next workout. In three months, Slater added 10 pounds of muscle.

He even quit smoking.

Lest the star get sore, Slater also had an acupuncturist and massage therapist. A personal chef prepared protein- and carbohydrate-rich meals to help him increase his muscle mass.

``He had never worked out with weights,'' said Person, who also trains rocker Trent Reznor from Nine Inch Nails. ``He went through a pretty major transformation.''

Training celebrities is a far cry from what Person originally wanted to do with his life - be a doctor.

But medical school didn't accept him, so a career in physical fitness seemed like the next best choice.

``I realized if someone was exercising correctly and eating correctly, it was basically preventive medicine,'' Person said.

CAPTION(S):

7 Photos

Photo: (1--2--Cover--Color) Supermodel Kathy Ireland and trainer Tim Green. Green helped Ireland (above) lose pounds gained during her pregnancy.

(3--Color) Personal trainer Karen Voight, left, puts Elle Macpherson through her aerobic paces in ``Your Personal Best Workout.'' Working out with Voight, the supermodel lost 20 pounds.

Michael Owen Baker/Daily News

(4) Angela Bassett worked out with weights and followed a carbohydrates and protein-rich diet for her portrayal of Tina Turner in ``What's Love Got to Do With It.''

(5) Christian Slater beefed up with weights five days a week for the action movie ``Broken Arrow.''

(6) Demi Moore toned up an already muscular frame by running and doing body-sculpting exercises.

(7) `I realized if someone was exercising correctly and eating correctly, it was basically preventive medicine'

Todd Person

personal trainer