This Secret Exercise Move Can Trim Three Inches Off Your Waist, Says Expert

Before he was the Governator, Arnold Schwarzenegger was known as The Austrian Oak. He was huge. In his heyday as a bodybuilder, the five-time Mr. Universe and six-time Mr. Olympia stood 6-foot-three, weighed between 225 and 235 pounds, and sported 22-inch biceps, a 57-inch chest, and 28.5-inch thighs. And his waist; can you guess?

Just 30 inches.

Like a lot of old-school bodybuilders, Schwarzenegger got that hourglass-shaped torso using a special technique based on a common pose used in physique competition in the 1970s known as the "vacuum pose." Bodybuilders like Frank Zane, Lee Haney, Arnold, and others would suck in their bellies to emphasize the chest in competition. But the vacuum pose is a great exercise for the rest of us, too, even if we only pose in front of the bathroom mirror. The exercise, called the "stomach vacuum" or more accurately, the "inner-ab vacuum" has been credited with relieving back pain, strengthening the core, and reducing the waistline by one inch or more in as little as three weeks.

"Your inner-ab muscles, called the transverse abdominals, act as a natural weight belt, like the kind you see workers wear in Home Depot," explains exercise researcher Ellington Darden, PhD, a pioneer of the Nautilus Training System. "When you contract those muscles that lie horizontally deep underneath your abs, it increases inner abdominal pressure to support your spine."

Those muscles also are responsible for good posture and for keeping your organs in place. So, by strengthening them you automatically pull your belly up and back, reducing its apparent size.

Darden says doing this simple move a few times a day, in addition to a strength training program and a healthy diet, can help anyone trim their waist size. Darden devotes an entire chapter to the slim-down technique in his book Flat Belly Breakthrough for Women. Here's an abbreviated how-to. Read on, and for more on healthy eating, don't miss 15 Underrated Weight Loss Tips That Actually Work.

Lie on your back in bed.

Having an empty belly will help you perform the move correctly. While lying on your back, place your hands on the bottom of your rib cage, at the top of your abdominals muscles. Take a normal breath and forcibly blow out as much air as possible for about 8 seconds.

Suck it up.

Suck in your stomach (this is the vacuum move) as far as you can using only your inner-abdominal muscles. In other words, do not breathe air into your lungs to help during this process; use only your ab muscles. Done right, it should feel as if you are trying to suck your navel into your backbone.

Hold it.

You won't be able to hold this position very long. But try for 8 to 10 seconds. You should feel and see a concave formation under your rib case. Then release and breathe. Try the vacuum several more times while lying down. "If you experience a little lightheadedness, that's normal," says Darden. "Just rest a bit longer between tries."

Stand and suck.

Now that you've got the motion down, stand up and move in front of a mirror to try the vacuum. Due to gravity, the inner-ab vacuum move is more difficult to do in a standing position. But with a little practice, you'll be able to master it. Practice this for 10 or 15 minutes a day for three consecutive days to commit the move to muscle memory. Related: The Perfect Time to Exercise Every Day, Says a New Study.

Do it before dining.

Darden asks his trainees to perform the inner-ab vacuum twice before every meal, breakfast, lunch, and dinner. Why? For one, it's an easy schedule to remember. Doing it before a meal is also an effective way to make you more mindful of your stomach and what you're putting into it right before you eat, says Darden. Speaking of lunch…check out 20 Best Lunch Habits to Drop 10 Pounds.