Over the past fifty years, scientists have
provided plenty of evidence that the benefits of exercise are important, even
crucial, for good health. Although physical activity can reduce your risk of
many illnesses, its most important impact is on cardiovascular disease. Even
modest exercise, puts stress on nearly every part of your body, it shouldn't
scare you away from exercise. In fact, if the stress of exercise is applied
properly, nearly every part of your body will respond by growing stronger and
healthier. The result is true fitness. It's not measured by how fast you can
run, how much you can lift, or how big your biceps are. Instead, real fitness
is measured by how well your body can withstand stress of all sorts: the stress
of exercise, the stress of disease, the psychosocial stresses of
twenty-first-century life, and even the stress of the aging process.
Exercise can make you fit and healthy. The
trick is to know how to exercise properly and then to make it part of your
daily life. And the way to start is by understanding how exercise affects your
body. Even the most committed couch potato has sprinted to catch a bus or an
elevator, and all of us can remember how it feels to exercise. Physical
exertion makes your heart beat faster and harder. Your breathing also gets
faster and deeper. If you're at it long enough, your skin will get flushed,
warm, and damp with perspiration. Your muscles will be taut from effort, and
they may ache and stiffen up for some time afterward. If you are really pushing
yourself, you may notice some nausea, abdominal discomfort, or lightheadedness,
and you might enjoy high spirits right after you come to a stop, only to feel
tired, sleepy, or a bit grumpy later in the day.
You don't have to be an exercise
physiologist to know that exercise makes your heart, lungs, and muscles work
harder or that your metabolism speeds up, producing extra heat. But even though
an occasional burst of exercise may enable you to catch a bus or enjoy a
sporting afternoon with the kids, it won't do much for your health. For fitness
and health, sporadic exercise won't do—but regular exercise will do very nicely
indeed. The body responds to the stress of habitual exercise with a remarkable
series of adaptations that are collectively known as the training effect.
Hippocrates didn't have the benefit of modern exercise physiology, but the
Father of Medicine seems to have predicted the training effect some twenty-four
hundred years ago when he wrote "that which is used, develops; that which
is not used, wastes away." Regular exercise will produce long-term changes
in many of your body's organs and functions. But at the heart of your
improvement is your heart itself.
Obviously everyone desires to live long,
but no man would be old. The clock ticks for all living things, and with each
tick, things change. Exercise can't stop the clock, much less turn back its
hands—but it can slow the tick and keep people healthy and vigorous, with the
physiological capacities of much younger individuals. Exercise should help keep
you young for your age. But does it actually work? The researchers had tested
the men before and after exercise, finding devastating changes that included
faster resting heart rates, higher systolic blood pressures, a drop in the
heart's maximum pumping capacity, a rise in body fat, and a fall in muscle
strength.
Vigor and health are wonderful, wonderful
things, but longevity doesn't hurt, either. Cicero
Scientists have gathered facts by
evaluating elderly men in Hawaii , Seventh-Day
Adventists in California , male and female
residents of Framingham , Massachusetts ,
Harvard alumni, elderly American women, British joggers, middle-aged
Englishmen, retired Dutchmen, and residents of Copenhagen
