The Secret to a Flatter Belly

Imagine if your belly always looked as good as it does when you turn sideways in the mirror and suck it in. Ab exercises can help, but 5—or even 50—minutes of crunches won't do any good if you're letting it all hang out for the remaining 23 hours of the day.

One of the abdominal muscles' biggest jobs is to hold our bodies upright, and research shows that rampant poor posture puts these muscles to sleep, leaving Americans in a constant belly-bulging slump. It's a particularly pesky problem for women who've had children. Stretched ab muscles and carrying kids can make it difficult to stand up straight for years after delivery.

The good news: "Correcting poor posture can make you look 5 pounds slimmer instantly," says Deborah L. Mullen, a certified strength and conditioning specialist in San Luis Obispo, CA. To keep that trim profile 24-7, you need to retrain and strengthen those belly-slimming, stand-tall muscles, so Prevention went to the nation's top posture pros for their best advice.

A Wake-Up Call for Flatter Abs

In an Australian study, researchers zeroed in on exactly what your muscles do while you're hunched over your computer.

They tested 20 people as they sat slumped in chairs and stood with their backs arched and bellies pooched out, and then again when they stood and sat erect. Not surprisingly, key posture muscles in both their bellies and backs were slack when they slouched; those muscles jumped to attention when the volunteers straightened up."The less we use our muscles, the weaker they become," says posture researcher Thomas Cowan, MD, a neurologist at Millard Fillmore Hospital in Buffalo, NY.

The fix: Strengthen and reinforce your ab and back muscles with Pilates, suggests a 6-month pilot study of 18 chronic back pain sufferers. "After 30 sessions, 15 of them got phenomenal relief," says Cowan, who conducted the study. "They had the strength and flexibility to support proper posture."

Back Straight, Head Up, Tummy In

Ballerinas make it look easy, but maintaining good posture can be a battle. "All of our senses are in front of us; we lean forward to look, eat, smell, touch, even hear," says John Friend, founder of Anusara Yoga, a style that focuses on alignment.

"And all that forward leaning tightens the muscles in the front of the body and weakens those in back."

Pilates Moves

Do these exercises three times a week to strengthen the muscles in your back and belly so you'll stand taller and look slimmer.

Leg Lower and Lift

Lie on your back with your hands behind your head and your legs extended and lifted directly over your hips, perpendicular to the floor.

Point your toes toward the ceiling, turn your feet out slightly, and lift your head, looking between your thighs.

This is the starting position.

Inhale while lowering your legs toward the floor about 6 inches (don't arch your back). Exhale while lifting them back up.

Begin with four reps, and work up to eight.

Back Extension

Lie on your stomach with your arms at your sides, palms up. Place your forehead on the floor. Keep looking down as you contract your back muscles and lift your torso off the floor, lengthening through the top of your head and reaching through your hands back toward your feet. Pause, then lower. Do six reps.

Now, extend your arms overhead so your palms rest on the floor in front of you (like Superman flying). With your upper body still and your legs slightly apart, lengthen and lift both legs as high as comfortably possible. Pause, then lower. Do six reps.