The exercise myth: excessive exercise can harm your health!

Should we exercise to live longer? Can vigorous exercise prevent heart disease? How safe is jogging? What are the dangers of inactivity? All of these questions are part of the fads and fallacies of The Exercise Myth

(Editor's note: Ten years ago, Dr. Henry A. Solomon, M.D., an eminent New York cardiologist, shocked the world with his study of the hazards of excessive exercise. Since then, mounting statistics of fatalities and cardiovascular disease have confirmed Dr. Solomon's predictions.)

In the following interview, Dr. Solomon updates his concerns.

Q: There are tens of millions of people in the United States along who passionately have taken up the banner proclaiming that vigorous exercise ensure good health. Are they misguided?

A: They are the representatives of all those who have bought the mistaken idea that strenuous exercise promotes health and longevity.

Although there are probably millions of believers who work out in gyms, on handball courts, at tennis clubs, in dance classes, and at other meeting grounds, runners are today the most visible of those who incorporate vigorous and often punishing exercise into their everyday lives. They seek an unattainable goal.

Q: Where and when did the public get the idea that exercise to be effective has to be exhausting?

A: Social pressure to participate in the movement is quite real. So many people have told them it's good for them physically and emotionally. The distinctions among various benefits are rather blurred, to judge by the books and magazines that promote exercise. The titles of new entries into the field promise a blend of radiant skin, lithe figure, athletic prowess, and excellent health. Traditional magazines whether devoted to motherhood or fashion, have dramatically also altered their format and thrust to reflect the new emphasis on exercise.

Q: Do you suppose the high-pitched "hype" by celebrities embracing the fad overwhelms an individual's common sense and caution?

A: Knowledge and jargon aren't difficult to obtain. Bookstore shelves are filled with exercise books. treaties on how to run and when to run, on strengthening your body, and on changing it and making it better. The enthusiasm is catching. Jane Fonda's Workout Book was number one on the New York Times bestseller list for 51 weeks, and James Fixx's bestselling book on running sold nearly 1 million copies in hardcover alone. James Fixx subsequently collapsed and died at the peak of his popularity.

Q: You are saying that the exercise frenzy is being capitalized upon by opportunities for profit.

A: The consensus that exercise is beneficial -- reflected in the social, career, and media pressures to exercise, and the coupling of fitness to health, beauty, and sexual, social and business success -- is both the product of, and the impetus for, a variety of extravagant and unfounded claims about what exercise can do for you.

Many promise medical help. A highly successful exercise center in New York offers a "systematic program designed to strengthen your heart ... and help reduce coronary factors ..."

A professional dancer offers a course in aerobics that promises to strengthen the cardiovascular system.

Also, do not underestimate the influence of makers of athletic equipment, such as barbells, treadmills, trampolines, rowing machines, exercise bicycles, and jump ropes. In keeping with the coupling of exercise to beauty, status and success, consider the business of clothing in which exercise is equated with high fashion. Warm-up suits, running shorts, socks, shirts, hats, visors, sunglasses, and headbands are all promoted via an ingeniously successful amalgam of fashion and fitness. Include also running bras, and racquet bras -- effectively directed at women.

Q: We all know fashion can be expensive and wasteful. What is the harm in people indulging themselves in such fantasies?

A: This is my concern: the claims of longevity, improved cardiovascular health and immunity to heart disease. As a physician, I may hold a personal opinion about the social fringe benefits of exercise, but not a professional one. As a physician, however, I ought to have a professional opinion about health in general. And as a cardiologist, I must and do have a strong opinion about the specific relationship of exercise to cardiovascular health and longevity.

Q: More than a decade ago, you proclaimed that severe stress caused by excessive exercise could be deadly. As a distinguished heart specialist, you were able to back up your claims with statistics from you own abundant case histories. Famous athletes have headlined the death toll. Yet, few doctors seem to link the lack of longevity among athletes with your facts. Why?

A: Doctors have certainly put their own muscle behind the exercise bandwagon and enthusiastically leaped aboard as it began rolling. The medical profession provides a legitimacy for exercise where otherwise there would be none. When doctors sanction the exercise revolution, the accompanying commitments of money and time, as well as risks to health and safety, then become acceptable.

The first medical reference to the potential health-promoting qualities of exercise was a study of British transit workers published in 1953 in the English medical journal Lancet. The researchers compared the amount and severity of coronary heart disease among London bus drivers and bus conductors. They observed that the more sedentary drivers suffered more coronary disease than did the more active conductors, who ran up and down the stairs of the two-tier bus collecting fares.

The conclusion: Physical activity offers protection from coronary disease.

It should be noted, however, that the bus drivers had higher risk of heart disease before they began their sedentary jobs compared to the more active conductors, who had lower risk before they began their active jobs. In other words, higher-risk people selected less active work, and lower-risk people selected more active work.

Inactivity, in these cases, did not cause heart disease; rather, people at higher risk for heart disease self-selected inactive jobs.

The research has been considered flawed by some critics.

There was no great public reaction to the appearance of this technical paper in a scientific journal, but it had considerable impact on the medical profession, who saw in it a glimmer of hope for the prevention of heart disease. To this day, the study is considered a landmark, its conclusions well known to most physicians.

Q: Was this study performed by a team of British researchers enough to cause a sweeping reaction throughout the United States and Great Britain?

A: After the publication of the scientific report, a steady stream of articles concerning the possible health benefits of physical activity began to appear in medical journals, keeping exercise as a topic of medical concern at a high level. Meanwhile, a diagnostic stress test was coming into common use, and it lulled doctors into believing that they could thereby diagnose the condition of a patient's heart and could even determine whether exercise was safe for the person.

The idea underlying the first stress test was that abnormalities of the heart that were not apparent at rest could become evident under conditions of physical stress. In other words, physical stress -- exercise -- could provoke abnormal cardiac responses. Since the heart works harder during activity, physical effort could be used to bring out heart trouble. Conversely, if physical stress did not provoke abnormalities, then the patient's heart could be considered normal. The logical corollary was that a normal performance on the stress test meant that physical exercise was safe.

Q: Since it seems evident that such concepts of stress testing could prove to be hazardous, what incentives would propel physicians to advocate such tests?

A: Physicians who recommend exercise stress testing do not necessarily do it out of venality or solely for profit. Doctors themselves participate in vigorous workouts. Despite their medical training, doctors are also consumers like everyone else, subject to the same exercise ballyhoo and hype as the rest of the population. There are also steady promotional efforts by companies manufacturing all forms of computer operated exercise testing equipment directed at physicians. Stress testing fees are substantial, and because Blue Shield and other insurance providers pick up much of the cost of stress tests, financial considerations rarely dissuade patients from having the tests performed.

Q: You have often declared that fitness and health are not the same. What is the difference?

A: How we feel is largely dependent on what we can do physically -- what is called "fitness" -- but how we are may have little or nothing to do with this. Fitness and health are distinct and independent of one another.

Fitness is defined by your ability to do physical activity or to perform physical work, a measure of your functioning capacity. It does not reflect the presence or absence of disease and implies nothing about the actual health of your arteries or your heart.

Cardiovascular health refers to the absence of disease of the heart and blood vessels, not to the ability of an individual to do a certain amount of physical work.

Your overall cardiac health is determined by the condition of various heart structures, including the heart muscle, the valves, the special cardiac tissues that carry electrical impulses, and the coronary arteries.

Q: Isn't the health of the coronary arteries the basis for claims that vigorous exercise is necessary to maintain them?

A: Most of the improvement in functional capacity because of exercise is not even directly related to the heart. It comes from an effect on the peripheral muscle cells whereby they extract more efficiently and use oxygen from the blood. Dr. George Sheehan, the "guru" of running, has said, "You might suspect from the emphasis on cardiopulmonary fitness that the major effect of training is on the heart and lungs. Guess again. Exercise does nothing for the lungs; that has been amply proved... Nor does it especially benefit your heart. Running, no matter what you have been told, primarily trains and conditions the muscles."

Q: Since many physicians request their patients undergo stress tests before taking on a regimen of exercise, what should individuals know about their purpose and hazards?

A: Much of what you hear and see about stress testing is misinformation. Stress tests are designed mainly to detect or confirm the absence or presence of heart disease and to establish a safe level of exercise for you. Stress testing does neither of these reliably. It is, in fact, of very limited value and may produce misleading information, sometimes with dangerous consequences.

Q: Have there been fatalities as a consequence of the tests?

A: Some of the deaths that occur as a result of stress testing -- and deaths to occur -- happen in the period following the actual exercise.

The most common purposes of stress testing is to find out whether you do or don't have coronary disease. Implied in this is the notion that if the stress test doest not reveal coronary heart disease then you can conclude with confidence that you are free from it.

This conclusion is wrong. A stress test doesn't necessarily detect coronary heart disease, and a normal result is not firm evidence of the absence of coronary disease.

A stress test may show how well you can perform when pushed to work hard during exercise. It is a test of function or performance. But coronary disease is structural, a narrowing of the coronary arteries that carry oxygen-laden blood to the heart muscle. It is not a disease of performance and may not interfere with function at all. You can have nice, clean coronary arteries but also have a heart that doesn't perform well during hard work. You can have a heart that carries you through a stress test with flying colors but coronary arteries that are already constricted with fatty deposits.

You can also have narrowing of your coronary arteries, even to a severe degree, and respond normally to a stress test. Stress testing is definitely an imperfect way to detect or exclude coronary disease.

Q: Longevity is one of the alluring promises of vigorous exercise. Is there any evidence that physical exercise can add years to one's lifetime?

A: Given the biological limit to longevity, the likelihood of attaining old age depends upon many things. Studies of the relationship between physical activity and mortality deal almost exclusively with death from coronary disease, and with good reason. Cardiovascular disease is the leading cause of death in industrialized societies, and any measurable impact on life expectancy would need to affect a major cause of death.

Autopsies of young American soldiers killed in the Korean and Vietnam wars have shown a surprisingly and disquietingly high incidence of early atherosclerosis. Yet surely most soldiers, tested, trained, and forced by circumstances to maintain strenuous levels of exertion, are physically active youths.

Can one at least guess that there are benefits from activity by showing that inactivity leads to coronary heart disease? There is a hint that excessive inactivity is related to coronary atherosclerosis. You must be truly sedentary -- a slug who sits about all day, or barely crawls from bed to breakfast, to car, to desk and back again -- to be at any risk from inactivity. No one who has to push a vacuum cleaner, play ball with children or keep the lawn mowed is that inactive.

Q: Can exercise slow down the progress of atherosclerosis once it has started or prevent more heart attacks once you have had one?

A: The physical condition of heart and arteries at any stage of disease does not improve with exercise. Even the best-designed and best-controlled studies show no reduction in frequency or severity of heart attacks, no slowing of the disease process, and no protection from sudden death.

Q: Some exercise advocates contend that high blood pressure can be reduced and levels of HDL (the high-density lipoproteins that are supposed to guard against heart disease) raised. Any validity to these statements?

A: The preponderance of medical evidence seems to be that clinically significant reductions in blood pressure are not achieved through exercise eve when it is performed vigorously and diligently.

A number of studies show no rise in HDL levels despite well-controlled exercise programs.

Q: Exercise does have its pleasures. Can you suggest a "safe and sane" pursuit of calisthenics?

A: Almost any form of exertion can be kept at a safer level if you don't drive yourself to overdo it. Even accident-ridden activities, such as skiing and running, can be done with less risk of injury.

Choose a less-demanding slope, for example, or try cross-country skiing instead of downhill. If you must cover much ground to enjoy yourself, trot, don't run. Cushion the impact of your joints with good sneakers and see whether you can find a soft running surface, such as a smooth dirt path instead of harsh or uneven pavements.

Q: Orthopedic risks must be less worrisome than the dangers of coronary events while one performs heavy activities. What is your advice?

A: Don't do anything to the point where you feel exhausted. Plan your exertion limit from the outset. That means long-distance running is not in the cards for most of us. Jogging may be acceptable, but only if you drop to a walk the moment your body tells you to slow down.

Most exercisers are taught to take their pulse by feeling the large pulsating artery in the neck, the carotid artery. Although the carotid pulse is strong and easy to locate, pressing on that artery can cause a sudden reflex slowing of the heart and a fall in blood pressure that leads to a blackout.

Occasionally, exercisers press both sides of the neck at once in their concern to take their pulse. It can cause a more severe slowing of the heart, but also effectively cuts off the blood flow to the brain. Take your pulse at your wrist, feeling for the radial artery.

PHOTO: Henry A .Solomon, M.D., practices cardiology in New York City, where he is on the faculty of Cornell University Medical College and an attending physical at New York Hospital.

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By Henry A. Solomon

Henry A. Solomon, M.D., is the author of The Exercise Myth, now considered a classic in the field of cardiology. It is currently out of print.

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