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Cardiovascular Endurance
The endurance needed to sustain general total physical effort for long periods of time is called cardiovascular endurance. A look at the basic physiological nature of the cardiovascular system will make clear
how this system affects the player.
Virtually every movement we make, as well as nearly every posture the body can assume, is caused by or supported by muscular contractions. Our muscles are constantly at work and, with
their every contraction, from the smallest movement to large-scale running movements, they require fuel to provide their energy. This necessary fuel is oxygen, taken from the air
and transported by. the blood to the muscles.
As the oxygen is used up by the muscles, it
must be replaced in the blood. This function is performed by the respiratory system. The respiratory system involves the inhalation of air and is made up of those organs of the body
especially equipped to take oxygen from the air and transfer it to the blood. The organs and body parts involved in this process are the nose and mouth, the lungs, and the passages for air
that lead to the lungs.
The circulatory system carries the blood to the various parts of the body where the oxygen is needed and used. The circulatory systems also carries the blood away from the muscles, taking
with it the wastes that have accumulated as a result of the muscles using and burning the oxygen. The blood then returns to the lungs, where it exchanges the used air and accumulated
wastes for freshly reoxygenated air.
The more strenuous the activity, the greater
the need for oxygen to support the increased muscular contractions. At this point, the heart's function becomes even more crucial to the circulatory process. The heart is a muscular
pump that pumps the oxygenated air into the blood, via the circulatory system, throughout the body. As the need for oxygen increases, the blood must be pumped faster to keep up with
the demands for energy being made by the muscles. The harder the muscles work, the harder the heart must pump to circulate the oxygenated blood and remove the wastes of respiration from the body. The signs
of this physiological activity are quite clear. As the muscles work harder, the heart speeds up and breathing becomes more rapid, bringing more air into the lungs, all to keep pace with the body's demands.
The conditioning task, then, in training for cardiovascular endurance is aimed at giving the player the ability to inhale large amounts of oxygen from the air, exchange it in the lungs
to the bloodstream, and circulate the oxygen efficiently through the entire body by way of the circulatory system.
This type of conditioning is based on providing the player with aerobic energy meaning that the energy supplied to the muscles is formed with air or oxygen. Good overall physical
fitness is built on having good aerobic energy formation capacity.
To achieve good aerobic capacity,
continuous physical activity must be performed regularly. Jogging, cycling, and swimming are examples of cardiovascular endurance builders.1 The objective is to raise the heart and pulse rate generally above 140 beats per minute and keep the
pace at that level for at least five minutes. The idea is to get the body, in its entirety, functioning beyond normal work levels, thus speeding up all the systems involved in general fitness. This
kind of training program can be enjoyed by any healthy person, regardless of age,
sex, or athletic ability. The one caution that applies to those beginning a fitness program, as well as to those undergoing Intensive sports training programs, is that a proper medical checkup be taken
before beginning such a program
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