Excercise, Activities and health problems
There is increasing evidence that exercise is of value in
preventing many key diseases such as heart disease, stroke, and peripheral
vascular dis- orders which affect circulation in the extremities. It is good
for most ACTIVITY AND THE HEART lung diseases; an aid in the prevention of
backaches and foot problems; a help too in the prevention of hernias; and a
means of maintaining good skin tone. . For many years, vigorous physical
activity was considered a hazard for the healthy heart, let alone the diseased.
Today, there is mounting evidence that regular activity not only is essential
for optimal maintenance of heart health but also, with certain precautions, can
be of great value in heart patients formerly doomed to inactive existence.
In one of the pioneering studies concerned with exercise and
the heart, British investigators found that the frequency of coronary heart
disease in London bus conductors was about 30 percent lower than in the less
active bus drivers. Since then, an inverse relationship between physical
activity and coronary heart disease-the more of the former, the less of the
latter-has been found by many other investigators in this country and elsewhere
in the world. In a study carried out by Harvard scientists, 700 Bostonians of
Irish descent were compared with their brothers who stayed in Ireland.
Coronary heart disease deaths in the Boston group (ages 30
to 60) were two times those in the Ireland group. The men in Ireland ate more
eggs, more butter, and more of other saturated fats-yet had lower serum
cholesterol levels. They consumed 400 calories more per day on the average than
their Boston counterparts but weighed 10 percent less. They were getting more
exercise and their lower cholesterol levels showed that physical activity does
more than just burn off calories. Somewhat to their amazement, American
scientists who recently made a special trip to study Masai tribesmen in Africa
found that these people, despite a diet containing enough cholesterol to send
the ordinary worried American fleeing in panic from the dinner table, never
seem to get heart trouble.
They live almost
exclusively on meat and on milk with a butter- fat content that soars to 6.5
percent. Yet they have lower blood cholesterol levels on the average than do
Americans. It is possible that it is exercise which protects Masai hearts,
keeping cholesterol levels in their blood low despite the high dietary intake.
The Masai are known to walk as much as 50 to 60 miles a day-and to do it
without strain. In a study covering 120,000 American railroad employees, the
heart attack incidence among sedentary office workers was found to be almost
twice that of men working in the yards. Investigators have noted that activity
trains the heart to beat slowly, to function more economically, to require less
oxygen for a given amount
