Certain natural changes take place in the heart as a result of aging, but the prescriptions for good heart health remain the same. Eat well and exercise regularly, regardless of your age. If you're over 65 and haven't been active, see your doctor before beginning a new exercise program, says Alison D. Schecter, M.D., F.A.C.C., an assistant professor at Mt. Sinai School of Medicine and co-director of the Women's CARE Program.

Natural changes as the heart ages:

• Your heart may get smaller.
• The number of heart muscle cells decreases with age and some degenerate. As a result, your heart may become weaker and pump less blood.
• Your heart valves may thicken and narrow. For some people, this could decrease the forward flow of blood, causing chest pain and shortness of breath over time.
• Your arteries may thicken and become less pliant, leading to high blood pressure. The electrical system that causes the heart to beat may change, showing changes in an ECG (this is not usually serious in people without heart disease).

Running Away from Aging
Remaining physically active is important, regardless of your age. And doing so might help fight off natural age-related changes in the cardiovascular system. A study in Circulation found that older athletes, on average in their 60s, had blood vessels that functioned as well as those of athletes in their 20s. "This study demonstrates that regular physical activity can protect aging blood vessels," says lead author Stefano Taddei, M.D., an associate professor of internal medicine at the University of Pisa in Italy. "Long-term exercise protects the inner lining of the blood vessels from age-related changes and makes them behave more like those of a young person."

The athletes in Taddei's study were long-distance runners, cyclists and triathletes, but you may not have to be participating in triathlons to reap the benefits. In 2000, a study by the Honolulu Heart Program found that walking more than 1.5 miles a day reduced heart disease risk in older individuals. "You do not need to be an athlete to get these beneficial effects from exercise," says Taddei. "Aerobic activity, five days a week, rather than intensive training, might just do the trick."

The Power of Positive Thinking
Yale researchers found that older people exposed to positive ideas about aging lowered their blood pressure under mild stress, while those exposed to negative ideas saw sharp increases in their blood pressure. In the study of people aged 62 and older, participants sat in front of computer screens while words flashed so quickly that they couldn't be recognized. Some people were shown positive words such as "wisdom" and "insightful" while others were shown negative stereotypes of aging such as "senile" and "decrepit." Afterwards, participants were given stressful math and verbal tasks and their blood pressures were measured.