Chapter Four
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Chapter Four:
Becoming Physically
Fit
© 2009 McGraw-Hill Higher Education. All rights reserved.
Basic Concepts
Physical fitness
A set of attributes that people have or achieve
that relates to the ability to perform physical
activity
Physical activity
Any bodily movement produced by skeletal
muscles that results in energy expenditure
Exercise (subset of physical activity)
Planned, structured, and repetitive activity
designed to improve or maintain physical fitness
© 2009 McGraw-Hill Higher Education. All rights reserved.
Four Components of Physical
Fitness
1. Cardiorespiratory endurance
Aerobic vs. anaerobic exercise
2. Muscular fitness
Strength vs. endurance
3. Flexibility
4. Body composition
© 2009 McGraw-Hill Higher Education. All rights reserved.
Cardiorespiratory Endurance
Ability of the heart, lungs, and blood
vessels to process and transport oxygen
over a period of time
Produced by exercise involving
continuous, repetitive movements
Examples: brisk walking, jogging, cycling
Aerobic (with oxygen) energy production
Structural and functional benefits
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Muscular Fitness
Strength: Ability to contract skeletal
muscles to a maximal level
Endurance: Ability to contract skeletal
muscles repeatedly over a long period of
time
Improved by performing repeated
contractions at less than maximal levels
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Flexibility and Body Composition
Flexibility: Ability of your joints to move
through an intended range of motion
Body composition: The make-up of the body
in terms of muscle, bone, fat, water, and
minerals
Fitness experts are most concerned with
percentages of body fat and fat-free weight
© 2009 McGraw-Hill Higher Education. All rights reserved.
Developing a Personalized Fitness
Program: Key Principles
• Overload: Placing increasing amounts of
stress or resistance on the body causes
changes that improve fitness
• Specificity: The type of exercise must be
specific to the outcome that is targeted for
improvement
• Reversibility (regression): “Use it or lose it”
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Cardiorespiratory Endurance
Training Factors
1. Mode
2. Frequency
3. Intensity
4. Duration
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Developing a Cardiorespiratory
Endurance Program
1. Mode of activity
Continuous activity
Using large muscle groups
Aerobic in nature
Enjoyable
Cross-train and/or vary activities to maintain
motivation
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Developing a
Cardiorespiratory Program
2. Frequency (How often should I train?)
3-5 times/week
More than 5 times/week will not create further
improvement
Less than 3 times/week will not show significant
improvement
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Developing a
Cardiorespiratory Program
3. Intensity (How hard should I train?)
Target heart rate (THR) = Between 65% and
90% of maximum heart rate
Maximum heart rate can be estimated by
subtracting your age from 220
Target heart rate range = (220 – age) x 65-90%
Sample calculation for a 20-year-old:
220 - 20 = 200 x 0.65 = 130 bpm
220 - 20 = 200 x 0.90 = 180 bpm
© 2009 McGraw-Hill Higher Education. All rights reserved.
Developing a
Cardiorespiratory Program
4. Duration
•
•
ACSM recommends 20-60 minutes of
continuous activity
The lower the intensity, the longer the
duration should be
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Muscular Fitness
Types of Muscular Fitness Exercises
Isometric (“same length”): Muscle contraction
without movement
Isotonic (“same tension”): Muscle contraction with
movement against a specific fixed resistance
throughout the full range of motion
Isokinetic (“same motion”): Muscle contraction with
movement against variable resistance through the
full range of motion at a fixed speed
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Muscular Fitness: Equipment
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Muscular Fitness
Frequency: 2 times/week
One set of 8-12 repetitions (10-15 repetitions for
adults over 50) of 8-10 exercises
Multiple sets could provide greater benefits
Sufficient resistance to fatigue major muscle
groups (legs, arms, shoulders, chest, back)
Training recommendations
Isotonic or isokinetic exercises
Full range of motion at a slow to moderate speed using
rhythmic breathing
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Major Muscle Groups
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Flexibility
Failure to maintain flexibility can result in
reduced range of motion and injury
Two forms of stretching motions:
Static stretching: Slow lengthening of a muscle
group to an extended stretch, followed by a hold of
the extended position for 10-30 seconds
Recommended
Ballistic stretching: A bouncing form of stretching in
which a muscle group is lengthened repetitively to
produce multiple quick, forceful stretches
© 2009 McGraw-Hill Higher Education. All rights reserved.
Flexibility Training
Stretch all major muscle groups
2-3 times/week
Should be done following a warm-up
Static stretching is preferred over ballistic
stretching
Hold each stretch for 10-30 seconds
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Body Composition
Measurement of percent body fat is often
included in a fitness program
To reduce body fat, an exercise program
should maximize caloric expenditure
ACSM recommends exercise sessions expending
300-400 calories
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The Workout Routine
Warm-up (5-10 minutes of slow, gradual,
comfortable movements related to the upcoming
activity; can end with a period of stretching)
Conditioning (cardiorespiratory endurance,
strength training, and/or flexibility workout
following ACSM guidelines)
Cooldown (5-10 minutes of relaxing exercises to
return the body to a resting state)
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Exercise and Aging
Change is gradual
Individual differences occur
Greatest change is noted in
areas of complex function
Homeostatic decline occurs
with age
Stay physically active to slow
physical decline
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Changes in Older Adults
Decrease in bone mass and changes in bone
structure
Decrease in muscle bulk and strength
Decrease in cardiorespiratory endurance
Loss of nerve cells
Decrease hearing and vision abilities
Decrease in sensory modalities
Slower reaction time
Gait and postural changes
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Exercise for Older Adults
Exercises for younger adults may be
inappropriate for people over aged 50
Supervision from a certified instructor may be
necessary
Physical exams are recommended before
beginning a program
Well-designed programs should start slowly
Recognize signs of distress
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Special Health Concerns
Low-back pain
Affects 4 out of 5 adults at least once in their
lifetimes
Mechanical (postural) problems tend to be the
main culprit
Regular physical activity greatly reduces the
occurrences of low-back pain
© 2009 McGraw-Hill Higher Education. All rights reserved.
Special Health Concerns
Osteoporosis
Decreased bone mass;
may lead to fractures
80% of suffers are
women
Lower level of estrogen
may decrease calcium
absorption
Adequate calcium and
vitamin D intake; weight
bearing exercise
Osteoarthritis
Joint inflammation
Common in older adults
Often occurs in weightbearing joints
Genetic predisposition is
also a key factor
Regular physical activity
may reduce the risk for
osteoarthritis
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Training Recommendations
Drink enough fluid before,
during, and after activity
Wear comfortable clothing
that promotes
temperature regulation
Use appropriate safety
equipment
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Effects of Steroids
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Exercise Injuries: Strategies
for Prevention and Care
1. Start at a low level and progress gradually
2. If you stop exercising for an extended time,
do not restart at the level at which you
stopped
3. Listen to your body
4. Follow rehabilitation instructions carefully
5. Develop a preventive approach to all
injuries
© 2009 McGraw-Hill Higher Education. All rights reserved.
Chapter Four:
Becoming Physically Fit
© 2009 McGraw-Hill Higher Education. All rights reserved.