Each year, more than 700,000 Americans suffer heart attacks -- and it can be a long road to recovery.
CBS News' chief medical correspondent Dr. Jon LaPook found an ancient form of exercise can be "medication in motion."
In the early morning hours in a New York City park, there's a quiet revolution in exercise.is a Chinese practice dating back centuries. It connects mind and body using slow, deliberate movements.
"I have never in any other exercise had some thing that was both energizing and relaxing at the same time," said Susan Werbin, 73.
Werbin has taken tai chi classes for more than 15 years. A recent study found it improves balance, especially in older people, and may reduce the rate of falls by more than 40 percent.
"You're moving slowly, you're oiling your joints, you're letting everything flow together," Werbin said. "It's sort of the use it or lose it."
Now, there's evidence it can be used to fight heart attacks.
Cardiac rehab can help heart attack patients recover more quickly. But the American Heart Association says greater than 60 percent don't do it.
Dr. Elena Salmoirago-Blotcher of Miriam Hospital in Providence wanted to see if tai chi could help. Twenty-nine heart attack patients who declined cardiac rehab entered a six-month tai chi program. Twenty-five of them completed the program and also increased their level of physical activity.
"Someone said, 'I got back on my bike, I felt like I could do it again -- things that I was doing before my heart attack and then I got scared and that gave me the confidence to do it again,'" Salmoirago-Blotcher said.
Fear of another heart attack is a common reason for declining cardiac rehab. So, if larger studies confirm this one, the researchers believe tai chi could be a way of gently easing into a more vigorous exercise program.