DR. DAVE'S FITNESS FACTS
Exercise and Disease Prevention
The leading causes of death in the United States are life-style related. Approximately 70 percent of all deaths are caused by cardiovascular disease (CVD) and cancer. Approximately 80 percent of these could be prevented through practicing positive lifestyle habits. Positive lifestyle habits include performing regular cardiovascular exercise, maintaining a healthy diet and an acceptable body composition, and not smoking.
The leading cause of death in the United States is coronary heart disease (CHD). CHD is a condition in which the arteries that supply the heart with blood become narrowed with the buildup of cholesterol. Any area of the heart that is being supplied by this blood vessel will die because it is not getting the oxygen and nutrients that is carried in the blood. Narrowing of these arteries is called atherosclerosis and may eventually lead to a myocardial infarction (heart attack).
One of the major ways to lower your risk of suffering from atherosclerosis is to decrease the saturated fats in your diet. Saturated fats produce low density lipoprotein (LDL) cholesterol which adheres to the walls of arteries and causes atherosclerosis. The American Medical Association recommends that your total cholesterol level should not exceed 200 mg/dl (milligrams/deciliter). A cholesterol level of 200 to 239 is borderline high and anything over 240 is too high and will greatly increase your risk for atherosclerosis.
Another way to decrease your risk of atherosclerosis is to perform cardiovascular exercise. Cardiovascular exercise will cause your body to produce high density lipoprotein (HDL) cholesterol. HDL cholesterol is known as the good cholesterol because it binds with the LDL cholesterol so that it cannot adhere to an arterial wall. The amount of HDL cholesterol that the body can produce is genetically determined, and women have higher values than men. That is one of the reasons that women have fewer heart attacks than men. Many researchers believe that the ratio of total cholesterol to HDL cholesterol is a better indicator for CHD than is the total cholesterol value by itself. A ratio of 4.5/1 (total cholesterol/HDL cholesterol) or lower is excellent for males and 4.0/1 is best for females.
Several factors can lower the HDL cholesterol levels in the body. Beta-blocker medication (used in treating hypertension), tobacco usage, and birth control pills all have a detrimental effect on HDL cholesterol levels. A combination of two or three of these is even worse.
One indicator of a person's current fitness level is his or her blood pressure. A low blood pressure means that the body is working efficiently, while a high blood pressure reading (hypertension) is a risk factor for cardiovascular disease. Blood pressure is the amount of force that is exerted against the lining of the arteries and is expressed in two numbers. An ideal blood pressure would be 120/80 or lower. The top number indicates the amount of pressure being exerted against the arterial walls while the heart is contracting (systole) and the bottom number is the pressure while the heart is relaxing (diastole).
If your blood pressure rises to 140/90 or higher, that is considered hypertensive. This condition puts excess strain on the walls of the arteries and may actually cause damage to the arterial wall. As blood pressure rises, so does the risk of atherosclerosis. Cholesterol cannot adhere to an arterial wall unless the wall has been damaged. Therefore, the higher the blood pressure, the greater the damage to the arterial wall which leads to increased atherosclerosis. Elevated blood pressure also causes the heart to work harder, which could eventually lead to congestive heart failure. Furthermore, hypertension damages the blood vessels of the kidneys and the eyes which could lead to kidney failure and blindness.
Ninety percent of all hypertension can be controlled through exercise and diet. Many studies have indicated that over ninety percent of hypertensive patients who initiate an aerobic exercise program significantly lowered their blood pressure. Diet is also important in lowering blood pressure. One of the most significant factors contributing to hypertension is too much salt in the diet. High levels of salt (sodium chloride) causes water retention which increases blood pressure. Although sodium is essential for normal physiological functions, only one-tenth of a teaspoon or 200 mg is required on a daily basis. It is recommended that you consume approximately 2400 mg of sodium daily. The average American diet contains between 6,000 and 20,000 mg per day (Hoeger, 1989). It is no wonder that over 60 million Americans have high blood pressure!
Cigarette smoking is the single largest preventable cause of premature death in the United States. Tobacco related illnesses costs the American economy over $200 billion annually and contribute to one out of every six deaths in the United States (over 400,000 people each year). Tobacco use is the major risk factor for cardiovascular disease; chronic bronchitis; emphysema; cancers of the lung, larynx, pharynx, oral cavity, esophagus, pancreas, and bladder; as well as other problems such as respiratory infections and stomach ulcers. According to Hoeger, 1989, smoking releases nicotine and some 1200 other toxic chemical into the blood stream. Similar to hypertension, many of these substances can damage arterial walls and lead to increased atherosclerosis. Pipe, cigar, and smokeless tobacco users also increase their risk for cardiovascular disease. Even if no smoke is inhaled, small amounts of toxic chemicals can be absorbed through the lining of the mouth and enter the blood stream.
People who smoke more than two packs of cigarettes per day are 15 to 25 times more likely to die of lung cancer than people who never smoke (Greenberg, Dintman, and Oakes, 1995). Nevertheless, the risk for both cardiovascular disease and lung cancer starts to decrease the moment you stop smoking. Following cessation of smoking for ten years, your risk of developing cardiovascular disease approaches that of a lifetime nonsmoker!
The human body has approximately 100 trillion cells, and during normal conditions the growth of cells occurs in an orderly fashion. The growth of cells occurs so that old and damaged tissues can be replaced with new cells. Sometimes, these cells can grow in an uncontrolled and irregular manner. These cells may grow into a mass of tissue called a tumor, which can be either benign or malignant. A malignant tumor is called a cancer. Cancer cells grow uncontrollably and kill normal tissue. The immune system will destroy most cancers, but sometimes the cancer can grow uncontrollably. If these cancerous cells spread to other parts of the body they are said to have undergone metastasis.
Cancer develops from a number of different causes. Tobacco is responsible for the greatest number of cancers. Approximately 75 percent of all lung cancers are caused by cigarette smoking, while smokeless tobacco and cigar smoking causes cancer of the mouth. Repeated and prolonged exposure to the sun is also a cause of skin cancer. Fair skinned people are particularly susceptible to the harmful effects of the sun. High fat diets are associated with cancer of the colon, rectum, stomach, prostate, and breast while diets low in fat and high in fruits and vegetables offer some protection against certain cancers. Also, excessive use of alcohol exposes one to the risk of cancer of the mouth, larynx, throat, esophagus, and liver.
Although not all cancers can be prevented, over 80 percent can be through positive lifestyle changes. According to Greenberg, Dintman, and Oakes, 1995, there are certain steps that you can take to lower your risk of developing cancer. These include:
Exercise has been shown to decrease your risk of developing cancer. Researchers have attributed this decreased incidence of cancer among physically active individuals to the fact that they are leaner than most people. Excess fat is associated with cancer of the colon, prostate, endometrium, and breast. The National Cancer Institute reports that people who engage in regular cardiovascular exercise have half the risk of developing colon cancer. Physical activity increases motility of the digestive tract. If there are carcinogens in the digestive system, the faster they proceed through the system, the less chance there is that they will attach themselves to the lining of the tract and develop into a cancer.
Obesity has become a health hazard in most of the developed countries around the world. It has been estimated (Hoeger, 1989) that approximately 35 percent of the adult population in developed countries is obese and over half of all adult Americans have a weight problem. This problem seems to be getting worse. The average weight of an American adult has increased 15 pounds in the last decade. When Yankee Stadium was renovated several years ago, total seating capacity had to be reduced to accommodate the wider bodies of the adult population.
Obesity an be classified as excessive accumulation of body fat; more than 30 percent over your ideal body weight. Obesity has been linked to a number of different health problems, accounting for 15 to 20 percent of the annual U.S. mortality rate. Obesity is a major risk factor for CVD, cancer, atherosclerosis, varicose veins, diabetes, osteoarthritis, hypertension, and strokes. In fact, if obesity were eliminated, the average lifespan could be increased by as many as seven years.
Obesity is caused by a combination of overeating and sedentary living. It has been found (Hoeger, 1989) that in only a small percentage of cases are glandular or other physiological disorders related to weight problems although many obese people blame these factors. Dieting is not the answer to getting rid of unwanted body fat. If a person tries to lose weight by dieting, up to half the weight that he or she loses may be lean body mass. Dietary manipulation should be combined with a regular cardiovascular exercise program. This will guarantee that the weight you lose is fat and not lean body mass.
Osteoporosis is the softening and deterioration of bone mass. Bones may become so weak that fractures often occur; in fact over 1.3 million fractures each year can be attributed to osteoporosis. Osteoporosis slowly starts after approximately age 30, and women are especially susceptible after menopause.
Prevention of osteoporosis includes exercise and mineral supplementation. Regular weight bearing exercise (walking, jogging, weight training) will cause the bones to become denser and stronger. Mineral supplementation is also important in preventing osteoporosis. Calcium is a mineral that is important in developing strong and healthy bones. The recommended dietary allowance for calcium is 800 to 1200 mg per day. In conjunction with adequate calcium intake, there may be a need for supplementing your diet with vitamin D, which is necessary for optimal calcium absorption.
Diabetes is a condition in which the blood sugar (glucose) is unable to enter the cells because of insufficient insulin production by the pancreas. This leads to abnormally high glucose levels (hyperglycemia) in the blood stream. Blood glucose levels of 150 - 160 mg/dl are considered to be borderline high and could eventually lead to health problems.
Diabetics may also have problems metabolizing fats which may lead to atherosclerosis, kidney damage, and vision problems. In fact, cardiovascular disease is the number one killer of all diabetics (over 80% of all diabetics die of CHD). Although there is a genetic predisposition to diabetes, adult onset diabetes is closely related to obesity. Diabetics need to follow a special diet so that their blood glucose levels do not rise too high and some may need to take insulin injections to help the cells of the body absorb glucose. Exercise is also very important for diabetics. Cardiovascular exercise will cause the cell to absorb glucose without the need for as much insulin. Exercise will also help with obesity which may be one of the triggers for the onset of diabetes.
If you have any questions regarding fitness and wellness, please feel free to contact me at (817) 648-6999.
|Copyright © Kinesiolgy Specialists, all rights reserved.|