Your heart is essentially one big muscle. And like any other muscle in the body, it needs to do work to stay healthy and strong. That's where regular cardiovascular fitness comes in. Think of cardio as anything that makes you breathe hard—such as vigorous walking—and that you keep up for several minutes. It's recommended that you participate in some type of physical activity for at least 30 minutes a day. Ease into it. Begin with a goal of every other day. And break the time into two 15-minute increments if you find that helps. Jogging, biking, swimming, or even brisk walking for 30 minutes every other day is proven to strengthen your heart. You don't need to break any world records; just try to push yourself a little bit harder than you did during your last workout. However, if you have any type of medical condition, consult your doctor before you start an exercise program.

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