What Personal Trainers Wish Every American Woman Knew

By Meg Lundstrom

They're buff, they're beautiful, they're fully booked by the hottest celebrities-but if these fitness trainers had a few minutes alone with you, here's what they'd say.

Name: Denise Austin

Works with: 1.4 million viewers of "Fit and Lite" and "Daily Workout" on Lifetime TV
Latest ventures: Hit the Spot Core Complete, Fit & Firm Pregnancy (DVDs, $15, out in September)
What I want you to know: "You don't have to do tons of sit-ups to tighten your tummy. Wherever you are-sitting in your car, cooking a meal, working at your desk-pull your tummy up and in, like you're zipping up a tight pair of jeans. If you hold it for five seconds, it's the equivalent of one sit-up. Practice this regularly every day, and in three to six weeks, you'll see results."

Name: Michael George

Works with: Reese Witherspoon, Julianne Moore, Toby Maguire, Meg Ryan, Christian Slater
Latest venture: 6-Week Virtual Coaching Program (BodyExpressMakeover.com, $60)
What I want you to know: "You have to give a new fitness program some time to deliver noticeable results. When you start cardio and strength training, you might actually gain weight at first because you're putting on lean muscle faster than you're dropping body fat. But if you're training the right way-high intensity training mixed with interval training-you're kick-starting your metabolism and should start dropping pounds in two to eight weeks."

Name: Kathy Kaehler

Works with: Julia Roberts, Kim Bassinger, Michelle Pfeiffer; NBC Today Show fitness expert
Latest venture: Free five-minute workouts for iPods and Mp3 players (GYMp3.com)
What I want you to know: "Your diet is about 75 percent of the weight loss battle. Don't think that because you went to the gym, or saw your trainer before work, or did an exercise video before bed, that you can raid the pantry. If you do not fuel your body properly, your results will be washed down the drain with your sweat. Follow a well-balanced, low-fat diet that includes lean protein, complex carbohydrates, and lots of fruits and veggies. Drink water, water, and more water."

Name: Jillian Michaels

Works with: Tara Reid, Amanda Peet, Vanessa Marcil, Nicole Kidman; fitness consultant to Redbook magazine's Real-Life Healthy Life campaign.
Latest venture: Winning by Losing: Drop the Weight, Change Your Life (book, $25)
What I want you to know: "Go beyond your "target fat-burning zone" when you do cardio. It's true that when you work out less intensely at a lower heart rate (65 percent to 70 percent of your maximum), you burn a higher percentage of fat calories over sugar calories. But when you get your heart rate up to at least 85 percent, you'll ultimately burn more total calories overall of both fat and sugar, making it a better weight-loss strategy.