"Why doesn't a lot of exercise wear out my heart?"

Your heart isn't like a car engine. It won't wear out with too much use. In fact, getting regular exercise can keep the ol' ticker going longer by allowing it to work more efficiently.

Just as exercise strengthens other muscles, like your biceps or abs, it also strengthens your heart muscle. A stronger heart doesn't have to pump as hard or as fast to send blood out to your body.

Exercising also helps reduce your heart's workload by lowering blood pressure, preventing obesity, and reducing levels of artery-clogging cholesterol.

You should shoot for at least 30 minutes a day of moderate exercise, like walking, cycling, or weight training.

Talk to your doctor before starting any exercise program. He or she can help you design a plan that's safe for your health and fitness level.

Remember that for exercise to help your heart, you need to do it regularly. It's advice worth taking to heart, if you want to keep that ticker going strong.