YOU Tip: Get Your Clothes Wet. We may not like to see sweat on treadmills or public speakers, but we want to see it on you. While we recommend different kinds of physical activity in different circumstances (including resistance exercise, walking, and stretching), the way to improve heart function is to sweat more than a kid in the principal's office. Why? Cardiovascular activity lowers both the top systolic (the pressure being exerted when your heart contracts) and the bottom diastolic (the pressure in the arteries when the heart is at rest) numbers of your blood pressure. Cardiovascular exercise may also be helpful because it makes your blood vessels more elastic by forcing them to dilate. In addition to thirty minutes of daily walking, aim for a minimum of sixty minutes a week of cardiovascular or sweating activity — ideally in three twenty-minute sessions — in which you raise your heart rate to 80 percent or more of its age-adjusted maximum (220 minus your age) for an extended period of time.

We recommend low-impact activities like swimming, cycling, or using an elliptical trainer to get your heart rate up without compromising the quality of your joints in the process (and to change activities, so you don't get repetitive use injuries from doing the same activity over and over). We also recommend interval training—that is, alternating periods of maximum effort with periods of recovery — for the maximum benefit of your heart. (Check with your doc beforehand; she may want to try it in the controlled setting of a stress test first.) Even doing one minute at the end of every ten with maximum effort can be beneficial.

One way to do it: After warming up, go for maximum effort for a minute, and then slow down to 60 percent of maximum (recover) for two minutes. Then go to 80 percent of maximum for seven minutes. Then cool down. As you progress, you can do intervals, alternating between intense effort and effort that allows you to recover — one minute fast, two minutes slow, and so on.