EXERCISE IS MEDICINE

Every one of us has had one experience or another with medicine. The word “medicine” brings many things to mind such as white coats, stethoscopes that smell of rubbing alcohol, the occasional shot, and medication. Some of us could throw surgery in that list. Webster’s defines medicine as the science and art of diagnosing, treating, curing, and preventing disease, reliving pain, and improving and preserving health. All most everything in this definition involves us when it comes to our own health. Leaving the diagnosing to health care providers, we need to be an integral part of treating and curing ourselves, preventing disease, reliving pain, and improving and preserving health. One way this can be done is with exercise. Taking this responsibility does not require a medical degree. It does however require some information. What exactly does exercise do for you? We have all been lectured on the benefits of exercise, but can exercise be included under the definition of medicine? If we can change our paradigm, and include exercise in our definition of medicine, would it also allow us to accept it on the same scale of importance? When we get sick, we think of getting better. We also think of doctors and medication to help us reach that objective. If we understood that exercise was a form of medicine, would it not also be a knee jerk response, “If I want to avoid (or treat) disease I better exercise”.

Exercise, like medication and surgery, is at the crux of disease treatment and prevention. If we arm ourselves with the knowledge of what exercise can do, I believe we will be more apt to partake in it. I hope to demonstrate that just like medication and surgery, exercise can be used to treat and in many cases cure a lot of disease states we all fear. But exercise also has the distinct advantage of preventing disease as well. Only a few medications and a few surgeries are actually preventative. The rest are needed after the fact.

Research has demonstrated protective effects of varying strength between physical activity and risk for several chronic diseases. In the following paragraphs, I will summarize (with references) how exercise is medicine. Recall our definition of medicine as you read the following. I will focus on particular disease states, and provided references to that can be utilized if more information about a particular subject or disease is needed.

General Health

A large number of scientific studies (1,2) and controlled, experimental investigations (3) have demonstrated that adults engaged in physically activity or exercise, as contrasted with their sedentary counterparts, tend to develop and maintain higher levels of physical fitness. Not only has being involved with exercise demonstrated benefits, lack of exercise has shown actual determents! Studies have shown that low levels of habitual physical activity and low levels of physical fitness are associated with markedly increased all-cause mortality (death) rates. (4,22) Even if one was to start an exercise program at mid-life; they have a decreased mortality. (23) It has been estimated that as many as 250,000 deaths per year in the United States, approximately 12% of the total, are attributable to a lack of regular physical activity. (24,25)

Cardiovascular Disease (CHD)

CHD is one of the leading killers in our society. Exercise has been shown to not only prevent the occurrence of CHD, but also modify its course once it is present. (4-6,7,8) Experimental studies showing that exercise training improves all aspects of cardiovascular risk factors including blood lipid profile (cholesterol level), (26) resting blood pressure in borderline hypertensives, (9,27-29) body composition, (30-32) glucose tolerance and insulin sensitivity having to do with the onset and control of diabetes (another major risk factor in heart disease). (33,34)

When doing studies like the ones mentioned above, researchers utilize epidemiological criteria to establish causal relationships, or “if this-then that” associations between what they are researching (exercise) and how it effects specific disease states. This is done to show definitive proof that one effects the other. When doing so, a few criteria must be met. These criteria are as follows: Consistency, or how often the two are related. Strength, how strongly they are associated. Temporal sequencing, does one follow the other. Dose response, does more or less of one effect the other differently. And finally, plausibility and coherence or is it possible by mechanisms we know to exist that one affects the other. Applying the association between exercise and heart disease (39) the following principles of causality appear to have been met: Consistency: The association of physical inactivity and risk of CHD is observed in a number of settings and populations, with the better-designed studies showing the strongest associations. Strength: The relative risk of CHD associated with physical inactivity ranges from 1.5 to 2.4. This means that if you do not exercise you have a 1.5 to 2.4 greater chance of dying from heart disease than those who do exercise! This increased risk is similar to the dangers to the heart when one has high cholesterol or high blood pressure or smokes cigarettes. (6,40) In other words, if you do not exercise, you have a risk of heart disease similar to having high cholesterol, high blood pressure and smoking! Temporal sequencing: The observation of physical inactivity predates the diagnosis of CHD. Dose response: Most studies demonstrate that the risk of CHD increases as physical activity decreases. Plausibility and coherence: Physical activity reduces the risk of CHD through a number of physiological and metabolic mechanisms. These include the potential for increasing the level of high-density lipoprotein cholesterol (HDL or good cholesterol); reducing serum triglyceride levels; reducing blood pressure; enhancing fibrinolysis and altering platelet function, thereby reducing the risk of acute thrombosis or blood clots; enhancing glucose tolerance and insulin sensitivity; and reducing the sensitivity of the heart to the effects of hormones that increase heart rate and blood pressure when we are under any form of stress (catecholamines), thereby reducing the risk of ventricular arrhythmia’s or abnormal heart rhythms. (9,26,33,41,42)

High Blood Pressure

High blood pressure or hypertension is a leading risk factor in heart disease, strokes, kidney disease, eye problems, etc. Exercise has shown not only to help prevent the onset of hypertension but also help modify the treatment of it. (9,10-12) I have had the opportunity in my practice to lower or even take people of their hypertension medications because they began and maintained an exercise program.

Type II Diabetes Mellitus

Diabetes is a well know cause of health problems ranging from increased heart disease, kidney disease, blindness, vascular complications, neuropathy or loss of sensation and/or increased pain in extremities. Exercise has been shown to not only help prevent this form of diabetes but it to can be used to help control it and thereby increase life vitality and expectancy. (13-15)

Osteoporosis

Osteoporosis is a degenerative disease of bones. It causes increased risk for fracture, disability and chronic pain syndromes. It affects activities of daily living and can be related to increased mortality due to associated fractures and further complications. Exercise has been shown to slow down the occurrence, and increase the density of bone, thereby reducing the risk of fractures and associated complications. (16-18, 35)

Colon Cancer

Even cancer is affected by exercise. Exercise has actually been shown to decrease the risk for colon cancer. (19)

Psychiatric Conditions

Psychological function and exercise have shown an emphatic relationship. Exercise not only makes you feel good in the short run but also has been shown to positively effect anxiety and depression. (20,21,38)

Immune Function

The function of your immune system or internal disease fighting complex can be improved utilizing exercise. (36,37) This has a profound impact on not only major diseases such as cancer but also on your everyday cold and viral syndrome. Most of the studies cited above have been utilizing endurance exercise in preventing chronic diseases. However, one cannot overlook the importance of flexibility and muscular strength in viewing exercise as medicine. Clinical experience and studies suggest that people who maintain or improve their strength and flexibility may be better able to perform daily activities, may be less likely to develop back pain, and may be better able to avoid disability, especially as they advance into older age. Regular physical activity also may contribute to better balance, coordination, and agility, which in turn may help prevent falls in the elderly. (43)

As you can see, the most common and occasionally feared disease states that can afflict us can be influenced by exercise. Just as medication and surgery, things we recognize as medicine, have profound influence on disease states, so does exercising! This form of medicine however is in your control. Your reward is based on your effort. In this day of all of us feeling as if we are loosing power over many aspects of our lives, we still have one area that no one can claim. That area is our health. We can treat ourselves in prevention, treatment, and some cases cure of disease. For this reason, Exercise IS Medicine!

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