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Trim Down Your Spare Tire

For many Americans, trying to get those washboard abs, or at least trim down the size of that spare tire has become an obsession. CBS News Saturday Morning's fitness expert Bonnie Kaye explains how.

Having strong abdominal muscles doesn't just look good, it's helpful for your back, too. For the best results, you'll need cardiovascular exercise, weight training, a healthy, low-fat diet, and of course, the right ab moves.

When thousands of fitness instructors from 65 countries recently gathered in Las Vegas for the 1999 World Fitness IDEA Convention, they learned that they can crunch it, twist it, pulse it and squeeze it. But if they're not doing it effectively, the exercise is a waste of time.

Exercise physiologist and researcher Len Kravitz of the University of New Mexico explains the correct way to work those abs. "A lot of videos say they have the best order," Kravitz said. "But if you really look at the research, you know that the best order is a spontaneously changing order, so that you constantly shock the muscles in a different way, and they will respond better."

Next, Kravitz suggests pressing the heels into a chair for better ab isolation. Pushing down on the chair actually contracts the back of the leg. This contraction in the back of the leg inhibits or lessens the effect of the front of the thighs. So you know what has to do the work? The abdominal muscles.

And when it comes to the number of repetitions, it's quality, not quantity that counts. Just two basic exercises will cover the ab bases. First, the basic ab crunch will tone your middle abdominal region, or rectus abdominis, which runs from the rib cage to the pelvis.

Next, torso twists will target the waist area, or internal and external obliques, which wrap around the waist and attach to the muscles in the lower back and play a key role in preventing back pain.

Remember to do the exercises slowly, with good concentration to the point that you feel comfortably challenged - as few as 10 to 15 repetitions for most people.

And contrary to popular belief, it is not necessary to exhale at the point of contraction, as done, for instance, during weight training, which is an all-out exertion at near maximal effort. Ab work is a submaximal, continuous exercise, where normal breathing is preferable.

A few beginner's tips that will help you perform a better ab crunch. First of all, keep the lower back flat against the floor, relax your head and neck into your hands but don't pull up on your neck.

A good way to avoid that temptation is to cross your arms on your chest, or extend out the arms by your sides. If you have a sore neck, use a towel to help cradle your head for comfort.

Even though you will hit most of the muscles with this basic crunch and the torso twist, add a third, simple exercise to target the lower region of your rectus abdominis. Bring one knee to the chest at a time, then both knees toward he chest, concentrating on contracting the very lower part of the abdomen.

To learn more about the 1999 World Fitness IDEA Convention, go to The conference gathers fitness professionals to exchange ideas and share the latest workout trends.

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