While you're jogging through the local park with your beloved but paunchy pooch, consider the way your kids jump, run, roll around and burn zillions of calories. They use whatever props are at hand to create imaginary worlds and exercise their way to stronger, more agile and healthier bodies. Instead of the stupor-inducing exercises adults think of as essential for a toned core and gravity-defying backside, kids make exercise fun. Find physical activities that pique your interest as well as your heart rate. One of the best ways to establish and sustain an effective exercise regimen is to find a physical activity you actually enjoy. That way, you'll be more likely to stick with it for the long haul.