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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