WHO hasn't been caught in a traffic jam—ahead, behind, and
on every side—cars, trucks, cars and more cars. Fumes build up.
Tempers flare. Yet, there isn't much that we can ordinarily do about
it.
Internally twentieth-century sedentary man is full of traffic jams. But nature's freeways have a solution! The Creator has so designed the freeways of our bodies that when we exercise our arteries get wider and wider, so that the traffic of the blood can keep right on rolling along. It is estimated that our red blood cells spend approximately 90 per cent of their travel time at top speed. As exercise widens the arteries in the legs, arms, and muscles, it draws blood away from congested areas such as the brain, stomach, and other internal organs. It balances the circulation.
Traffic jams in the body are more than frustrating—they actually damage. Too much blood in the head tends to bring on headaches. Too much blood pressing around the heart tends toward palpitation.
Now let's consider the greatest pump in the world. It usually beats faithfully for about 70 years—an average total of more than 2.5 billion strokes, pumping 18 million barrels of blood during this time. But, like any pump, it needs repair, and repair takes place during rest periods called diastole (dye-ASS'- to-lee). Every beat (contraction) is fol lowed by rest, and the rest is normally longer than the beat. The slower the heart rate the more time there is for rest and repair, because it is the rest period that is especially prolonged when the rate is slower. This means more rest per day. So the slower the normal heart beats the better.
Champion athletes and men who work hard and steadily are noted for heart rates even into the 50's, 40's, and occasionally lower. They achieved this by consistent, vigorous exercise. Even sedentary animals like pet rabbits have faster heart rates than their more active relatives out in the fields.
Most hearts would profit immensely by gradually slowing them down. The so-called "average" of 72 heartbeats per minute for adults is merely an average and, like average cholesterol levels, may be often far from ideal. Most of us can slow down our heart rates by gradual, sensible, consistent exercise. This slowing indicates that the heart is handling its work load with fewer contractions (more blood per beat).
The coronary arteries are the living pipes that supply the heart muscle itself with blood, carrying life-giving 62 and nourishment.
Most of this blood flow occurs during diastole, so the slower the rate of the normal heart the greater the coronary blood flow, and hence more oxygen for the heart muscle. Here, too, prudent physical work or exercise helps the heart.
Exercise can also help the coronary arteries indirectly, as it increases the efficiency of the circulation in the large muscles, such as those of the legs. Thus less blood is needed to do the same job. This decreases the load on the heart, requiring less coronary blood to nourish the heart muscle. This adaptation assists the heart even if the coronary arteries should not enlarge.Now for some good news. Experiments with animals have shown that exercise can increase the size of the coronary arteries and the number of their tiny branches. This allows a greater supply of blood to reach the heart muscle.
Although in man exercise alone has been insufficient to enlarge narrowed coronary arteries, this provides encouraging indication that a total prudent program of spare diet, properly selected food, control of stress, and professionally supervised exercise may also improve blood supply to the heart in a similar fashion.
There is a special enzyme called fibrinolysis (or plasmin) that helps prevent the formation or dissolve already formed blood clots inside the body. Comparison of the effects of moderate and excessive exercise, with explanatory comment. "Let your moderation be known unto all men" (Phil. 4:5). Moderate exercise increases the activity of this clot-dissolving enzyme.
Excessive exercise, particularly in competition or stress, fills the blood with hormones that tend to promote dangerous blood clots. Excessive exercise also fails to provide enough fibrinolysin, hence the blood-clotting system is pushed out of balance—too much tendency to clot and insufficient clot- clearing capacity. This may help to explain some heart attacks.
Brisk exercise, especially in the new outdoor air of morning, fills the lungs with oxygen-containing air. The little pipes to the lungs open up widely and blood streams through the lungs spritely carrying vitality out to all parts of the body. The lungs thrive on exercise. Vital capacity of the lungs is increased, particularly if exercise is enjoyed earlier in life.
Muscle
What does exercise do for the other muscles of our bodies? Like the heart muscle, they must have a constant sup ply of blood. The more active they are, the richer their blood supply and the more work they can do. Exercise can increase the size and efficiency of the muscles that are exercised. But, a word of caution. This is one of the problems with activities that overemphasize one group of muscles. The muscular system is unbalanced.
Conversely, unused muscle shrivels and eventually becomes unable to function. Not only is muscle itself benefitted, but because we are about 40 per cent muscle, almost every body organ and system can be improved or influenced by proper use of muscles in consistent exercise.
Actually, the rate of increase in muscle strength is about twice as great when exercise is done in outdoor sunshine than indoors.
Exercise and Other Body Functions
As to other parts of our bodies, the digestive system functions better when we exercise moderately. Experiments show that its after-meal activity in creases with brisk walking, but decreases with intemperate exercise.
Kidneys. Even our kidneys, which filter and purify the blood, may function better with moderate exercise that reduces stress and improves the circulation. It often also increases the drinking of water, and water is an absolute necessity for kidney function.
Skin. The skin is assisted in its work by moderate exercise that brings more blood to the surface, thus providing better nutrition to it. Moderate amounts of sunshine and fresh air combine with brisk exercise to potentiate its effects.
Excess exercise, particularly in hot humid conditions, cannot only be counter-productive but even dangerous. The body becomes overheated, in part because the skin blood flow is not adequate, and the heart may not be able to keep up with the added load. Congestive heart failure may result. Also the kidneys may shut down. So it is best not to engage in vigorous competitive exercise in excessive heat, especially in humid conditions and immediately after a meal. Plan something lighter then.
The Brain. Unfortunately, the brain and the rest of the nervous system, certainly of the utmost importance, are usually neglected in discussions of the physiology of exercise. Yet, the effects on them are vital. Exercise can significantly improve alertness and arousal of the brain. Brain fatigue has been shown to be much less when one is on an exercise program. A good brisk walk or a period of productive work is excel lent to brighten up the brain.
Stress of mind can be handled much more successfully when we get this type of judicious exercise because we can really think about only one thing at a time. Becoming absorbed right here doing this, figuring out how to fix this thing and get it going again, this is a kind of exercise that unites the senses, the mind, the motives, feelings, and the muscles to work in synchrony and is excellent for stress control.
Sleep. "The sleep of a labouring man is sweet" (Eccl. 5:12). This Bible physiology is excellent. Wholesome fatigue, particularly with the sense of grateful accomplishment, is better than any sleeping pill to help us sink gratefully into deeper, more restful and invigorating sleep than the sedentary person can ever know. You will find that you enjoy next morning's Bible study with new power of insight, new grasp of the Good News. Great mountains of truth stand out in bold profile. Mole hills of man's tiny opinions sink into true perspective. Indeed, we must rediscover the value and the experience of the balanced life.
Exercise, Work, and the Character
The whole world is waiting for leaders who excel in character. Sharpness, smoothness, and appearance are not enough. The want of the world is the want of men who know how to combine power of will and power of self-control.
Every strong brace, every neat, tough joint, every stroke of labor in the carpenter's shop of Nazareth was a stroke to build not just muscle, but to build that model character that overturned the world. Trace down through history the great leaders of destiny. Note how hard work, with the head, heart, and muscles all working together, was a winning combination to build men physically, mentally, and spiritually.
Action
In view of the broad sweep of advantages, what are we waiting for? Let's start a regular exercise or work pro gram, beginning sensibly and avoiding the distortions brought by competition and by the attempt to prove to every body or even ourselves that we are champions. We are getting ready for the New Jerusalem—not Athens. Day by day, week by week, gradually increase your investment in work or exercise and you will find that your whole life will grow.
Those of us who have physical problems or are well along in years should get professional guidance in developing our exercise program. Use variety, use your imagination. Make things, do things. Thousands of us don't walk nearly enough; yet walking is the best exercise for moderation and practical availability. After you realize what in creased exercise has done for you, share it with others. Health is an achievement, not an accident, and is for those who value it enough to invest the time and energy it demands.
