You feel fine, but you feel fat. The warmer weather is coming. It’s time to start working out. After all, dieting has not really done the job of shedding pounds picked up during the holidays. So you start jogging … or swimming … or riding an exercise bike … and you find that it’s hard.
The thought crosses your mind: Is this more than hard? Might it be unsafe? Could you turn out to be one of those weekend athletes who dies from a heart attack while warming up for exercise?
This question is not a sign of neurosis. Exercise can be hazardous to your health. There is a small risk of a heart attack or serious heart-rhythm abnormality during exercise and for the couple hours immediately afterward. But compared to the great benefits of regular exercise, the stress you put your heart through is worth it. People who exercise regularly have a much lower overall risk of dying from heart disease than do inactive people. How can you tell whether it is safe to launch into an exercise campaign? The first thing I do when patients raise this issue is to run through a series of questions aimed at unmasking previously overlooked heart problems. These questions include:
If patients do not have any warning symptoms, I review any heart-disease risk factors: cigarette smoking, diabetes, hypertension, high cholesterol, low HDL cholesterol, a family history of heart disease, and a sedentary life style. I examine them to check their blood pressure and listen to their heart and lungs. If they are middle aged or older, I order an electrocardiogram and some routine blood tests.
If all these questions and tests are normal, I send them on their way, and tell them to lose a pound a month. Many of them, however, want an exercise test — if for no other reason than the fact that their neighbor had one.
A stress test is a wonderful way to diagnose heart disease, but I rarely order one for patients who do not have any symptoms or physical evidence suggesting heart disease. In other words, I don’t believe in the “routine screening exercise test” performed in someone who seems basically healthy.
The reason is that exercise tests have “false positive” rates of about 15%. In other words, for every 100 perfectly healthy people who take an exercise test, about 15 will be wrongly diagnosed as having a heart problem. And it may take a cardiac catheterization before they can rest assured that their hearts are normal.
Cardiac catheterizations are usually safe and uncomplicated procedures, but not always. Almost every cardiologist can remember patients who had serious complications such as a stroke during cardiac catheterizations that turned out to show no significant heart disease. It’s bad enough when a complication occurs after a cardiac catheterization that really was necessary to care for a patient’s heart disease. It’s another story when the stroke occurs after a catheterization that really wasn’t necessary.
I think I can diagnose heart disease early enough by asking patients questions about symptoms they may get when exerting themselves. But some cardiologists — many of whom are real experts — have a different philosophy. They believe in the use of exercise tests for “high risk” patients who have multiple risk factors for atherosclerosis, such as diabetes, hypertension, and high cholesterol. The advocates of exercise testing believe that, in such high-risk patients, an abnormal stress test is highly likely to indicate atherosclerosis in the arteries of the heart, which should lead to instructing the patients in how to reduce their risk factors, and which may perhaps shed a new light on vague symptoms that a patient notes. An odd stomach pain that was once written off as heartburn might finally be recognized as angina.
A compromise I make is that I often walk patients out to a stairwell down the hall from my office. With the patient, I walk up three flights of stairs to the roof of Brigham and Women’s Hospital. We both huff and puff along the way, but if the patient can do it without getting suspicious symptoms, I know that the risk of serious heart disease is low. If the patient gets chest discomfort or some other possible form of angina, I am quick to get a stress test to see if the symptoms come from the heart.
Whether or not your physician does this kind of test with you, or orders a full formal exercise test, the real key to safety when starting an exercise program is to listen to your body. If you get symptoms such as chest pain or pressure, stop, rest, and then give your physician a call. A fainting spell is another reason to see your physician immediately. Start slowly, and build up your exercise program gradually. Common sense is more valuable than medical technology any day.
Thomas H. Lee, M.D. is the chief executive officer for Partners Community HealthCare Inc. He is a professor of medicine at Harvard Medical School. He is an internist and cardiologist at Brigham and Women's Hospital. Dr. Lee is the chairman of the Cardiovascular Measurement Assessment Panel of the National Committee for Quality Assurance.