Regular exercise, especially aerobic exercise, is one of the best things you can do for yourself. It helps cut your chances of getting heart disease. It's good for your blood pressure, cholesterol, weight, energy level, and mood, too. If you're not active now, check in with your doctor before you start. She’ll let you know what you can do safely. If you take any prescription medicines, ask her if you need to adjust them when you start exercising.