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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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