If your children seem uninterested in exercise or not motivated, have you considered that they might actually be afraid of it? One of the kids on Shaq's Big Challenge, Kit, was scared when she started exercising — she experienced a panic attack and almost quit the program. But instead, she familiarized herself with what it means to work out, and now she exercises all the time on her own.

Dr. Carlon Colker, the physician and trainer who worked with the kids on Shaq's Big Challenge, says that a child's fears are often created in the home. "The apple doesn't fall far from the tree," he advises parents. "If a kid has an issue like fear, chances are you have it, too. Your own issues need to be addressed." To get over your fear, start small. Shoot for a walk or jog around the block with your children. When you see that you've survived that, go a little bit farther each time you exercise until you reach your goal.

But the key is that you have to be at ease for your children to feel the vibe. "You tell them, 'It's just a sit-up; here, let me show you,'" Dr. Colker suggests. "You show them that they can do it." You are the most important influence in your children's lives, so work out your issues by working out. After a little bit of exposure to exercise for everyone, those fears will be a thing of the past.