Is Running Your Heart’s Desire?
It seems so, for the heart thrives on it. Running is also desirable for other parts of your body
WHAT RUNNING DOES FOR YOUR HEART
Makes it work less while doing more. With exercise the heart muscle’s fibers lengthen and strengthen, its chambers enlarge and as a result can pump more blood with each contraction. Before training, one stroke of the heart may pump less than half a cup; but after training, each beat may pump almost a whole cup. Because it pumps more with each beat, it beats slower and has more rest between contractions. From this training, over a period of time the heartbeats measured when you are at rest can show a decrease from 10 to 20 beats per minute. The small arteries that carry blood to the heart enlarge with training and are able to supply more oxygen-rich blood for the heart. Training also results in a gradual lowering of blood pressure.
WHAT RUNNING DOES FOR YOUR LUNGS
Strenuous exercise causes the muscle fibers to demand lots of oxygen. They get it from the blood, which picks it up from the lungs. The lungs, with their hundreds of millions of moist, foamlike bubbles of tissue known as alveoli, are efficient suppliers of oxygen to the blood that streams by them. They are very adaptable, changing quickly in response to exercise. The lungs’ blood vessels dilate, increasing the area where oxygen passes into the bloodstream. The breathing muscles of the abdomen, diaphragm and thorax become stronger and more efficient. The amount of air the lungs of a trained runner can take in increases greatly—the volume per minute perhaps tripling.
WHAT RUNNING DOES FOR YOUR BLOOD
Aerobic exercise produces in greater quantities the enzyme fibrinolysin. It dissolves blood clots, and it is theorized that it may also dissolve long-standing clots in the coronary arteries that could cause heart attacks. In one test the clot-dissolving ability of blood nearly quadrupled in some persons engaged in a 10-week exercising program. Trained runners have higher levels of high-density lipoproteins (HDL) in their blood. HDL transports excess cholesterol from artery walls, reducing buildups of fats that might clog vessels and trigger heart attacks. In trained muscles adjacent arteries sprout new branches and capillaries become more dense, making more oxygen available to muscle fibers. Exercise also increases the number of red blood cells, the oxygen carriers.
WHAT RUNNING DOES FOR YOUR NERVES
Nerves, even the tiny hairlike tendrils, become more efficient at transmitting electrochemical impulses, and thereby more effectively activate muscle fibers to increase endurance and ultimately strength. With training and use, reflexes replace voluntary actions and movement becomes more efficient. Unneeded muscles relax more and energy is conserved. Dr. Lucien Brouha, authority on the physiology of athletics, states: “The final result is that for a given performance a decrease in energy expenditure occurs which can reach one-quarter of the total energy needed before training.” Men are not mice, yet it is noteworthy that young mice that exercised developed larger motor neurons, a type of nerve cells, than those that didn’t.
WHAT RUNNING DOES FOR YOUR MIND
Runners speak of the joys of running and “natural highs.” More specifically, a psychiatric hospital in Knoxville, Tennessee, found that running made patients less anxious. Dr. Alan Clark of St. Joseph’s Infirmary in Atlanta, Georgia, says: “It is well known that exercise is the best tranquilizer. I refuse to medicate patients with simple neurotic anxiety until they give aerobic exercises an adequate trial.” An article in Medical World News was headlined: “Jogging May Keep Depressives Off Therapist’s Couch.” It reported two studies, from the University of Wisconsin and the University of Virginia, that confirmed this view. One study has shown that exercise stimulates production in the brain of the neurotransmitter norepinephrine, which relieves depression.
WHAT RUNNING DOES FOR YOUR MUSCLES
That muscles desire exercise should be apparent to everyone. Without it they waste away. The specifics of their functioning, however, are so amazing that they will be discussed in the following article. Also, a training of far greater importance will be considered.