Download Principles of Physical Fitness

Unit 1 - Principles of Physical Fitness
If ten people were asked to define physical fitness, it would not be surprising to get ten
different answers that are all partially correct. This variation occurs because physical
fitness can be categorized into two types – skills-related and health-related – with each
type having various components. Skill-related physical fitness includes power, speed,
agility, balance, coordination, and reaction time. Health-related fitness includes the
following five components:
1. Cardiorespiratory Endurance – the ability of the heart, respiratory, and circulatory
systems to supply oxygen and nutrients to, and to remove waste products from,
the working muscles.
2. Muscular Strength – the ability of the muscles to exert a force to move an object
or to develop tension to resist the movement of an object.
3. Muscular Endurance – the ability of a muscle to sustain repeated contractions or
to maintain a submaximal contraction.
4. Body Composition – the relative proportion of body fat to fat-free body tissues
(muscle, bone, organs).
5. Flexibility – the ability to move a body part fluidly through a complete range of
motion about a joint.
BENEFITS OF PHYSICAL FITNESS
A regular exercise program will result in numerous physiological adaptations. Benefits
to the individual are the ability to perform daily tasks with increased ease and the ability
to perform more total work throughout the day. The most generic of definitions of
physical fitness suggests it to be the ability to perform daily activities without undue
fatigue.
Physiological Adaptations
The benefits of exercise on the cardiovascular system are evident. The heart, which in
essence is a muscular pump, becomes stronger and more efficient. Cardiac output, the
amount of blood pumped from the heart each minute, is a product of stroke volume and
heart rate. The heart adapts to regular aerobic exercise training by increasing the amount
of blood it pumps with each beat (stroke volume), thus becoming a stronger, more
effective pump. Consequently, at submaximal workloads the heart does not have to beat
as often, thus reducing the demand on the heart. The body also responds by increasing
the total blood volume and the hemoglobin content in the blood. These two adaptations
allow the individual to deliver more blood and more oxygen to the working muscles
during exercise.
Unit 1 - Principles of Physical Fitness
Changes also take place within the muscles themselves. Basically the metabolic
machinery of the muscle cells is built up so that it can produce more energy. The muscle
can extract more oxygen from the blood, and the enhanced circulation through the muscle
helps to remove the additional waste products produced.
Exercising will also increase the individual anaerobic threshold, the point in metabolism
at which lactic acid begins to accumulate in the blood. Increasing the anaerobic threshold
allows the individual to work at a higher absolute submaximal workload without
fatiguing.
Regular aerobic exercise training can also improve an unhealthy individual’s body
composition. Through training, the muscles and bones are stimulated, which helps the
body maintain muscle tissue and increase the integrity of bone. At the same time, the
increased energy expenditure of training promotes the loss of body fat stores.
Psychological and Sociological Values
Regular exercise affects not only the body but also the mental and emotional states.
Exercise can serve as an outlet for pent-up emotions through socially accepted channels.
Stress, anxiety, and depression may be relieved by exercise, without the ills and side
effects of mood-altering drugs. Physically fit individuals speak of their enhanced mental
acuity, mental energy, concentration, and feelings of well-being. These feelings have
been documented in several studies. In addition, physically fit individuals have an
enhanced self-image, a definite sign of excellent mental health.
The late President Kennedy once said, “Physical fitness is not only one of the most
important keys to a healthy body, it is the basis of dynamic and creative intellectual
activity. The relationship of the body and the activities of the mind is subtle and
complex. Much is not yet understood, but we do know what the Greeks knew: that
intelligence and skill can only function at the peak of their capacity when the body is
healthy and strong; that hardy spirits and tough minds usually inhabit sound bodies.”
In this sense, physical fitness is the basis of all the activities of our society. And if the
body grows soft and inactive, if we fail to encourage physical development and prowess,
we will undermine our capacity for thought, for work, and for the use of those skills vital
to an expanding and complex America. Thus, the physical fitness of our citizens is a vital
prerequisite to America’s realization of its full potential as a nation, and to the
opportunity of each individual citizen to make full and fruitful use of her capabilities.
EXERCISE PROGRAMMING
Regardless of the type of training to be used, all exercise-training sessions should have
the same basic structure of beginning with the warm-up period, proceeding with the
Unit 1 - Principles of Physical Fitness
specific type of training, and finishing with a cool-down period. The purpose of the
warm-up is to prepare the body for the training session by gradually increasing the heart
rate and blood circulation to the active musculature. Walking, callisthenic-type exercises,
and stretching are appropriate warm-up activities. Although documentation is lacking,
many believe that warm-up activities serve a preventative function against injury.
The cool-down helps restore the body to its pre-exercise condition. Initially the cooldown consists of walking, which then followed by stretching exercises. It is believed that
the cool-down is the optimal time for making flexibility improvements since the muscles
are warm and the joints are most supple. Although many flexibility exercises are
available, a basic routine would include neck rotations, arm pullovers, side stretches, onelegged sit and reach, hip and knee flexion, and ankle rotation.
F.I.T.T. PRINCIPLE
Frequency. The frequency of the training program refers to how often the training should
take place, usually described in terms of days per week. Training needs to be performed
at least three days per week to derive physiological benefits. Further increases are seen
with more frequent training; however, for health-related physical fitness training, more
than five days per week is of little value. In fact, the body needs rest time between
training sessions to make the adaptations. Training six to seven days per week increases
the individual’s risk for injury.
Intensity. Intensity refers to the amount of effort or work that must be invested in a
specific exercise workout. This too requires a good balance to ensure that the intensity is
hard enough to overload the body but not so difficult that it results in overtraining, injury
or burnout.
Time. The time of the program is the duration spent in the training part of the exercise
session (not including warm-up and cool-down time). The minimum time necessary to
stimulate physiological adaptations is 20 minutes, with further increases seen through 60
minutes of activity. The recommended time range for most individuals is 30 to 40
minutes.
Type. What type of exercise will you be doing? Will an exercise session be primarily
cardiovascular, strength training or a combination of both? And, what specific exercises
will you perform.
Individualization
Frequency, Intensity, Time, and type of training are all interrelated. This allows the
capability of designing an exercise program to meet the individual’s physical capabilities
and psychological perceptions of the comfort of the exercise program. Also, factors such
Unit 1 - Principles of Physical Fitness
as availability of facilities, work or school schedules, weather, and medical restrictions
can influence the exercise-training program. To be effective, regular exercise must
become an integral part of one’s lifestyle.
Individualization can also take place by considering they type of exercise being utilized
for the training. Aerobic exercise types are those that use the large muscle groups in a
rhythmical, dynamic fashion. Activities such as walking, jogging, swimming, and
cycling are examples of aerobic exercise types.
A final consideration is the need to begin an exercise program at the reduced intensity
and duration and to progress slowly. As one becomes acquainted with the exercise
program structure and techniques used, he/she can gradually increase the intensity and
duration of the training session. This helps to reduce injuries at the beginning of the
program and also increases the individual’s self-confidence.
Recreational Activities
A question that often is asked is if one can use recreational activities for training. In
general, one should “get in shape to play the game, not play the game to get in shape.”
However, once an acceptable level of physical fitness is obtained, recreational activities
can be useful as a supplement to the training program to maintain the desired level.
Recreational activities can provide the necessary variety to the training program to make
the long-term commitment to regular exercise solid.
CLOTHING
Essentially the only piece of specialized clothing required for aerobic training is proper
footwear. Good exercise shoes provide adequate support and cushioning to protect the
feet and reduce the shock of the foot strike to the rest of the body. (Good shoes can take
on a force of approximately three times the body weight). The running/walking shoe
industry has gone high-tech with literally hundreds of different shoes, available with
variable features. One should shop for the shoes at a reputable dealer who has personnel
that can explain the various features of the different types of shoes and thus assist in
selecting the most appropriate shoe for the individual’s needs.
In general, exercise clothing should be lightweight and should fit loosely. Fashionable
exercise clothing has become very popular; however, care has to be taken to assure that
the clothing is breathable and allows moisture to evaporate from the skin. Seasons will
dictate how much to wear. In warm, humid weather, it is important to expose as much
body surface area as possible to allow sweat the opportunity to evaporate and thus help
keep body temperature down. In cold weather, layering lightweight clothing is most
advantageous because this allows removal of a layer (or two) as the body heat production
Unit 1 - Principles of Physical Fitness
increases. In extremely cold conditions, protection of the extremities is a must. A had
that covers the ears and either gloves or mittens are needed.
One myth related to exercise clothing is that rubberized sweat suits are helpful for
exercise and weight-loss programs. It is true that one can lose a substantial amount of
weight in an exercise session if a rubberized suit is worn. However, the weight lost is
from body water, not body fat, and thus is quickly regained. Not only are these suits
ineffective for reducing excess body fat, but they are also potentially dangerous, as
dehydration can cause body temperature to rise to dangerous levels.