Feb. 18, 2003 -- If it feels like you're pushing yourself, you're probably doing enough to help your heart.
A new study looks at this issue of exercise intensity. While current American Heart Association guidelines call for "moderate-intense activity," it's not always clear to exercisers whether they are doing enough. Should we push the envelope a bit more? This study is aimed at clearing up the mystery.
"We've always said that a good, moderate activity was brisk walking, at 6 mph.... If you are a marathon runner, that's a piece of cake. But if you are my 93-year-old grandmother, that's not very realistic, she couldn't do that," lead researcher I-Min Lee, MBBS, ScD, professor of medicine at Harvard Medical School, tells WebMD.
Her study appears in the current issue of Circulation: Journal of the American Heart Association.
In it, Lee and colleagues track the health of nearly 7,400 men -- all in their mid-60s -- to see how the intensity of their workout stacked up against incidence of heart disease from 1988 to 1995. The men rated their activities as weak or less intense, moderate, somewhat strong, or strong and intense. They found that 551 men developed heart disease -- heart attacks or angina -- or had heart procedures including bypass or angioplasty of a clogged artery.
Who didn't develop heart disease? Those who described their workouts as "intense" had 40% less risk, reports Lee.
Her rule of thumb: "If it feels somewhat difficult, then it's good for you. You are getting some heart benefit."
The study showed that the patient's perceived exercise exertion was a strong predictor of future heart health even among those who did not meet the current recommendation for moderate-intense physical activity.
Right on, says Joseph Miller, MD, a preventive cardiologist at Emory University School of Medicine in Atlanta. "There's a big misconception, that when we tell people to go out and exercise, we're not trying to turn you into a marathoner. The real goal is to start exercising, and to push yourself till you're feeling fatigued."
"I think we discourage people sometimes," Miller tells WebMD. "People have a vision that they need to be wearing spandex and get out and kill themselves, and that's really not the goal. If you're used to sitting at a desk all day, a 20-minute walk is what you need. You don't have to be speed walking."