The Human Body A Working Machine
In most animals, the demand for good mobility dominates body construction. This also applies to human beings. The human body contains more than 600 muscles; overall, it is more than half muscle. Muscles make possible every overt motion. They also push food along the digestive tract, suck air into the lungs, tighten blood vessels to raise blood pressure when you need more pressure to meet an emergency. The heart itself is a muscular pump. Technological advances have changed our way of living and have made strenuous physical exertion largely unnecessary but the needs of the human body have not changed. Muscles are meant to be used.
Many of our important organs and functions are dimensioned and designed to give service to the muscles during work-organs such as the heart and respiratory system. With the body at rest, the heart pumps out about 5 liters of blood every minute and at the same time from 5 to 8 liters of air are inhaled by the lungs. Keep in mind, however, that the heart’s construction permits it to pump from 15 to 20 liters (or more) of blood per minute and a person’s pulmonary ventilation may exceed 100 liters per minute. The nervous system can also be said to be dominated by the body’s demand for motion. To a large extent, the nerves receive and provide impulses that result in muscular movement: speech, gestures, physical work, running, etc. Depending on situation.
We’re built for action
The human body is built for action, not for rest. This was a historic necessity, the struggle for survival demanded good physical condition. But optimal function can only be achieved by regularly exposing the heart, circulation, muscles, skeleton, and nervous system to some loading, that is to say, training. In the old days, the body got its exercise both in work and at leisure. In our modern society, however, machines have taken over an ever increasing share of the work elements which were formerly accomplished with muscular power alone. Our environment has come to be dominated by sitting, riding, and lying. Thus, the natural and vital stimulation that tissues and internal organs receive through physical work has largely disappeared.
That we are, to a great degree, what our muscles make us weak or strong, vigorous or lethargic is a growing conviction among medical men. Offering strong support for this conviction is the following observation by a former president of the American medical Association : “It begins to appear that exercise is the master conditioner for the healthy and the major therapy for the ill. “A recent survey of physicians showed that almost all now believe strongly that positive health benefits, both physical and mental accompany physical fitness resulting from regular, moderate exercise.
Prevent trouble before it could begin
Paul Dudley White, the noted heart specialist, once said that “prevention of disease has attracted much less attention than its diagnosis and treatment. It obviously deserves the first priority, but it is less dramatic than surgical procedures, is rarely asked for by the not-yet-educated public, and the doctors are overworked simply taking care of sick people.
In many countries, cardiovascular diseases often account for more than 50% of all death. Naturally this fact motivates the intensive research presently being carried out to discover the genesis and treatment of such diseases. They certainly cause personal suffering and their social and economic consequences are enormous. In many countries, medical care is actually one of the largest industries, with a direct budget that has increased enormously during the past decades. In America, cardiovascular disease costs more than 22,7 billion dollars annually. In Sweden with a population of 8 million, the health budget covered by direct tax revenue is now close to four billion dollars. However, more money spent does not inevitably equal better health. Longevity, measured as the average remaining lifetime increased markedly in America in each decade from 1900 to 1960 but appears to have reached a plateau in the early sixties. Since that time, there has been virtually no increase for males and only a slight increase for females.
Admittedly, life expectancy is in no way an accurate refection of the state of health of a country. Life expectancy is determined from the death rate, whereas we measure our health, not when we die but while we live. The health of a country can only truly be measured by the quality of the life led by its citizens.
It is unrealistic to permit the cost of medical care to increase at the same rate as during recent decades. It would soon consume the total gross national income. Instead, much more effort and time should be devoted to preventive health programs. This booklet presents a summary of the physiological and medical information which analyses the connection between health and fitness. This type of message has proved to be quite successful at least in Sweden!
Actually, the increase in life expectancy over the past 70 years is largely due to a reduction I deaths of infants. In fact, the life expectancy of a 40 year old man over the past half decade has increased by merely one year! Many diseases, particularly infectious diseases, have effectively been conquered, but diseases of a degenerative nature, particularly cardiovascular disease, have increased extensively. One cannot avoid the thought that our modern way of life could be one important factor and that the main determinants of longevity are now more cultural than medical.
In recent years, interest has been focused on the possible role of physical inactivity in the genesis of these diseases. The pioneer in studies of the “epidemiology” of cardiovascular diseases, J.N. Morris, has emphasized that “habitual physical activity is a general factor of cardiovascular health in middle age, and that coronary heart disease is in some respects a deprivation syndrome, a deficiency disease”.
Why Exercise?
Athletes need to train to improve performances, but why should the rest of us keep in shape? As you will see from the following pages, the human body has been built for movement and that movement is a prerequisite for good overall bodily function. Regular exercise can be compared to the lubrication of a car. The regular lubrication keeps auto parts moving freely and exercise aids the overall performance of our body. In certain situations, good physical condition can even save lives; for examples, in emergency situations in the aim of regular training and exercise is not to produce great maximum strength but to achieve the essential by products which training provides.