The implication is that exercise is so dangerous it requires a physician's approval. This leaves many sofa spuds thinking it's safer to stay curled up on the couch.
But that's the wrong message, say an increasing number of health professionals. In our sedentary society, where an epidemic of inactivity is responsible for an estimated 250,000 deaths per year, the new message is that most people don't need a doctor's approval to start exercising at a low to moderate level.
Two basic factors determine whether or not you need a physician's approval to exercise, notes Dallas epidemiologist Steven Blair, who served as senior scientific editor for the 1996 U.S. Surgeon General's "Report on Physical Activity and Health": the intensity of the exercise you plan to do, and your health status .
Intensity of exercise
If you're considering a program of vigorous-intensity exercise, it's generally advisable to consult a physician first ? especially if you've been sedentary and are age 40 or over.
"But you don't need to consult a doctor to go out and take a walk," Blair notes.
What's your health status?
Your health status also affects whether or not you should check in with your doctor. If you answer "yes" to any of these questions, it's advisable to discuss your exercise plans with a physician:
Exercise is much safer than inactivity in terms of health and well-being, notes Blair and other experts, who say that rather than seeking permission to exercise, people should have to get permission to be sedentary because inactivity is the more dangerous state.
But while active people have a lower overall risk of health problems than do sedentary ones, it's important to be aware that physical exertion also can cause serious cardiovascular events. These typically occur as a result of relative overexertion in people with uncontrolled heart conditions.
That's why the American Heart Association advises a stress test for middle-aged and older people who have not been physically active and plan to begin a vigorous exercise program.
Who should get them?
"To be on the safe side, we recommend that people over 40 and those with risk factors for cardiovascular disease get at least one stress test if they want to do vigorous exercise," says AHA spokesman Gerald Fletcher, a cardiologist and professor of medicine at the Mayo Clinic Medical School in Jacksonville, Fla.
Risk factors indicating the need for a stress test, he says, include cigarette smoking, diabetes, obesity and family history of cardiovascular disease, particularly if a family member died young of a heart condition.
But for non-vigorous activities ? such as walking, pool aerobics and doubles tennis ? no physician's approval is necessary, he says.
"People can start exercising at a low to moderate intensity on their own without medical screening," notes Fletcher, who defines non-vigorous as "an activity you can do while carrying on a conversation."
When is it not safe to exercise?
There are a few grave medical conditions that might make exercise unsafe, such as severe aortic stenosis or a serious terminal or untreatable disease. But for most chronic conditions ? like heart disease and arthritis ? exercise is a well-recognized and effective therapy. So if you're not getting regular physical activity, you're missing an important part of your medical treatment.
Keeping it safe
To ensure the safety of your exercise, be sure to:
Carol Krucoff is an award-winning medical writer and health columnist, and the founding editor of the Health Section of The Washington Post, where her nationally syndicated column, "Bodyworks," is featured.
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