Is Your Workout Intensity Enough?
Current American Heart Association guidelines call for "moderate-intense activity". But it's not always clear whether work out intensity is sufficient to reap health benefits.
"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, states. Heart-effective exercise depends on your current level of fitness.
In her study, Lee and colleagues tracked the health of nearly 7,400 men from 1988 to 1995 - all in their mid-60s - to see how the intensity of their work out stacked up against incidence of heart disease. The men rated their activities as :
They found that 551 men developed heart disease - heart attacks or angina - or had heart procedures including bypass or angioplasty of a clogged artery.
- weak or less intense,
- moderate, somewhat strong, or
- strong and intense.
Who didn't develop heart disease?
Those who described their workouts as "intense" had 40% less risk, reported 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.
"There's a big misconception. 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. 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." says Joseph Miller, MD, a preventive cardiologist at Emory University School of Medicine in Atlanta.