Do
you have it? We all need it. It is very valuable, but we are
often careless about it. It is easy to lose and difficult to
get back. What is it? Physical fitness.
For a long time,
most people did not realize how important physical fitness was.
Today, however, we know that staying in good physical condition
not only makes life more enjoyable but also quite possibly helps
us live longer. That is why millions of people today participate
in some sort of strenuous exercise several times each week.
There are four foundations
to physical fitness. First, you must eat in an intelligent way,
based on principles of good nutrition. Second, you must get
plenty of rest and sleep. This is vital when you are growing,
and it is important at all times of your life. Third, you must
practice good hygiene and health habits, and you should avoid
dangerous substances such as tobacco and narcotics. Fourth,
you must get plenty of exercise. Exercise keeps your muscles,
heart, and lungs in good working order. There are many different
exercises, but just three basic kinds are necessary for physical
fitness. They are aerobic exercises, stretchers, and strengtheners.
Aerobics
It used to be that
doctors would recommend rest for their patients with heart problems.
This has changed. Now exercise is often recommended to help
strengthen weak hearts. Even normal, healthy hearts benefit
greatly from exercise. Doctors have discovered that the heart
is like any other muscle. Making it work strengthens it. The
heart is working hard when it is pumping hard.
Exercises that strengthen
the heart and lungs are called aerobic exercises. The word “aerobic”
means “with oxygen.” Muscles need oxygen in order to produce
heat and energy. Our lungs collect oxygen and feed it into our
blood. Our hearts pump the blood through the arteries and veins
of our circulatory system, delivering oxygen to every muscle
in the body.
The blood also carries
food to the muscles and takes away wastes produced as the food
and oxygen are used. When muscles have too much waste, they
do not work well. Your muscles become fatigued (tired). They
also become sore or develop cramps.
With an efficient
heart and a strong pair of lungs, however, you can work your
muscles hard for a long time without getting fatigued. And you
can be sure that every organ and tissue in your body is receiving
a healthy supply of food and oxygen.
What exercises will
strengthen your heart and lungs?
Running, jogging, bicycling, swimming, rope skipping, cross-country
skiing, basketball, soccer, and hockey are all aerobic activities.
Some people enjoy dancing as an aerobic exercise. Continuous
body movements, such as running in place, hopping in place,
or different exercises done without pauses between them may
all be aerobic. Even walking long distances has aerobic benefits.
Even long distances has aerobic benefits.
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