I'm trying to flatten my stomach. Crunches and sit-ups hurt my back. Would an ab roller help? Do you have one you recommend?

-- EbMbDb

Eb, it's not surprising that traditional sit-ups hurt your back. You end up doing more work with your legs and your lower back than you do with your abdominals.

Crunches can hurt your back and be unsafe if you have a history of lumbar disc herniations, but for most people they shouldn't be a problem. Perhaps your method of performing them needs a little fine tuning.

Let's start at the beginning. Lie flat on your back on a mat, thick carpet, or a couple of bath towels. Bend both knees and keep your feet flat on the floor about a foot and a half away from your hips. Lace your fingers together and place your hands behind your head. Curl upward and forward until you feel your lower back flatten against the mat. Ease yourself back down. Remember not to pull on the back of your head with your hands as you come forward, and keep your elbows back.

Your hands are there to cradle, not lift, your head. Keeping your elbows back will keep you from pulling forward and placing a strain on the back of your head. The basic crunch shouldn't hurt as long as you don't try to come all the way up or pull forward with your arms to try to get up.

If your back hurts from doing sit-ups, you probably need some back strengthening exercises. Lie flat on your stomach with your arms straight out in front of you and your head down. Raise one arm, the opposite leg, and your head and torso off of the floor, all at the same time. Lower yourself to the floor and repeat with the other arm and leg. Do 10 to 15 repetitions of this exercise on each side and then roll onto your back and hug your knees to your chest.

You asked about an ab roller. They're not necessary. It's better for to learn the proper way to do crunches without straining your back. That way you can do them anytime, wherever you are, without depending on a device such as the ab whatever.

Nevertheless, the better ones help take the strain off the back of the neck that so many people complain about. Liz Neporent, co-author of Fitness for Dummies and Weight Training for Dummies, once tried more than 25 ab contraptions. She felt that the Ab Trainer was a decent item. It is built sturdily and it does what it's supposed to do -- help you work your abs without straining your neck. But with time you could likely learn to do crunches on your own without the apparatus.

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