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Chapter 12
Flexibility
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
Chapter Objectives
After completing this chapter, you should be able to
1. Define and measure flexibility.
2. State why flexibility should be measured.
3. Describe the difference between relative and
absolute flexibility tests.
4. State the guidelines that should be followed in the
administration of flexibility tests.
5. Describe responsibilities after the
measurement of flexibility and prescribe activities to
improve flexibility.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-2
Flexibility
Flexibility is the ability to move the body joints
through a maximum range of motion without
undue strain.
*Not a general factor; specific to given joints and
to particular sports or physical activities.
Flexion – joint angle is decreased
Extension – joint angle is increased
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-3
Flexibility
Flexibility depends on the soft tissues of joints
(ligaments, tendons, and muscles) of a joint than
on the bony structure of the joint itself.
Bony structures of certain joints do place
limitations on flexibility, however.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-4
Flexibility
Flexibility also related to:
body size (body fat)
age
gender
physical activity
Loss of flexibility in aging process is probably due to
failure to maintain an active program of movement.
Generally, active individuals are more flexible than
inactive individuals (some exceptions, however).
Habitual postures and chronic heavy work through
restricted ranges of motion can lead to adaptive
shortening of muscles.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-5
Why Measure Flexibility?
Flexibility important component of health-related
fitness; lack of it can create functional problems or
disorders.
Low back disorders is one of the most prevalent
health complaints (second to common cold for
visits to doctors).
Many low back disorders are caused by poor
muscle tone of lower back, poor flexibility of the
lower back, and inadequate abdominal muscle
tone.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-6
Why Measure Flexibility?
Anyone with a stiff spinal column is at a
disadvantage in many physical activities; also fails
to get full value from shock-absorbing
arrangement of spine.
Lack of flexibility can be responsible for:
bad posture, compression of peripheral nerves,
painful menstruation
Short muscles also limit work efficiency; also
greater risk of injury during physical activity.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-7
Why Measure Flexibility?
Individuals with good flexibility have:
greater ease of movement
less stiffness of muscles
enhancement of skill
less chance of injury
Flexibility tests also can identify individuals with
too much flexibility.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-8
Responsibilities after Measurement
Appropriate flexibility exercises should be
prescribe for individuals with poor flexibility
Three stretching techniques can be used to
develop flexibility.
Static stretching involves slowly moving to a
position to stretch the designated muscles and
holding the position for a specified length of
time (20 to 30 seconds).
The stretch for each muscle should be repeated
two or three times in each stretching session.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-9
Responsibilities after Measurement
Ballistic stretching makes use of repetitive
bouncing motions.
Not recommended.
Force produced by effort to stretch may be
greater than the extensibility the muscle can
tolerate. Also induces the stretch reflex.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-10
Responsibilities after Measurement
Proprioceptive neuromuscular facilitation
(PNF) involves a combination of alternating
contraction and relaxation of both agonist and
antagonist muscles.
Requires the assistance of a partner.
Both static stretching and PNF will improve
flexibility, but lack of agreement regarding
which technique is superior.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-11
Responsibilities after Measurement
Studies have found that athletes who perform
a static stretch routine prior to participation in
power or explosive type events experience a
decrease in performance success.
Static exercises described at conclusion of
chapter.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-12
Tests of Flexibility
Clinical assessment - Leighton Flexometer, the
electrogoniometer, and the goniometer; provide
rotary measure; degrees of rotation around a 3600 arc
Practical tests – provide linear measure; tape
measure, yardstick
Relative flexibility - test score (movement) compared
with the length or width of a specific body part
Absolute flexibility - measure only the movement in
relation to an absolute performance goal
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-13
Pretest Instructions for Test Performers
1. Perform 5 to 10 minutes of light aerobic
exercise to warm up.
2. Perform slow, sustained static stretching of all
joints to be tested.
3. Declare if they have any back problems.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-14
Sit and Reach Tests
Sit and reach tests claim to measure lower back
flexibility.
Better measure hamstring flexibility.
Acceptable performance of sit and reach test does not
necessarily mean individual will be free of low back
pain.
Prevention of low back pain involves other factors
such as weight and trunk muscular strength and
endurance.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-15
Sit and Reach
Test objective. To measure flexibility of the lower
back and posterior thighs.
Age level. Five through adulthood
Logical validity; reliability coefficient reported.
Figure 12.1 included specifications of the box used
for this test.
Figure 12.2 illustrates test.
Table 12.1 includes norms for ages five through
college-age.
Other sit and reach tests; always use norms of test you
administer.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-16
Figure 12.1 Sit and reach box.
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Modified Sit and Reach
Individuals with short legs relative to the trunk
and arms may have advantage performing
previously described sit and reach test; modified
test accounts for this potential bias.
Test objective. Measure flexibility of lower back
and posterior thighs.
Age level. Under eighteen through fifty-plus.
Logical validity.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-18
Directions
Modified Sit and Reach
1. Test performer sits on floor with hips, back, and
head against wall, extends legs fully and places
feet against the sit-and-reach box.
2. Places the hands one on top of the other and
reaches forward as far as possible without letting
the head and back come off the wall; shoulders
may be rounded.
(A yardstick is placed on the box with zero end
pointed toward test performer and touching his/her
hands. Yardstick is held in place by test
administrator.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-19
Modified Sit and Reach Test
3. Gradually reaches forward three times, as
yardstick is held firmly in place. Holds third
stretch as far as possible for two seconds.
Scoring. Two trials administered. Score is
number of inches reached to the nearest onehalf inch.
Norms. Table 12.2 includes norms for ages
under 18 through fifty-plus.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-20
Sit and Reach Wall Test
Provides a quick estimate of lower back and
posterior thigh flexibility.
Age level. Junior high through college-age.
Logical validity; reliability not reported.
Table 12.3 includes norms for high school through
college.
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12-21
Trunk and Neck Extension
Test objective. To measure the ability to extend the
trunk (relative flexibility).
Age level. Six through college-age.
Face validity; reliability and objectivity coefficients
reported.
Figure 12.3 illustrates test.
Table 12.4 reports norms for college students.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-22
Trunk Extension
Similar to trunk-and-neck extension test, but
measures absolute flexibility.
Age level. Six through college-age.
Face validity; reliability not reported.
Figure 12.4 illustrates test.
Table 12.4 reports norms for college students.
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12-23
Trunk Rotation Test
Test objective. To measure trunk and shoulder
flexibility.
Age level. Six through adulthood.
Face validity; reliability not reported.
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12-24
Shoulder and Wrist Elevation
Test objective. To measure shoulder and wrist
flexibility (relative flexibility).
Age level. Six through college-age.
Face validity; reliability and objectivity
coefficients reported.
Table 12.5 reports norms for college students.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-25
Shoulder Lift
Similar to the shoulder-and-wrist elevation test,
but measures shoulder flexibility only (absolute
flexibility).
Age level. Six through college-age.
Face validity; reliability not reported.
Figure 12.5 illustrates test.
Table 12.5 reports norms for college students.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-26
Figures 12.6 through 12.13
This figures illustrate observation measures of
flexibility.
No scores are recorded for these measures.
Measures may be used to identify individuals with
inadequate flexibility.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-27
Exercises to Develop Flexibility
Guidelines for Static Stretching
• Spend 20 to 30 seconds in a gentile, static stretch
with each exercise; perform each exercise two or
three times.
• Increase the extent of the stretch gradually and
progressively, with full extension, flexion, or
both being placed on the joint.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-28
Exercises to Develop Flexibility
Guidelines for Static Stretching (continued)
• Breathe slowly, rhythmically, and with
control.
• Stretch beyond the normal length of the
muscle, but only to the point that a slight
stretch pain is felt.
• Practice regularly; perform the exercises
several times each day.
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-29
Exercises to Develop Flexibility
Flexibility is highly specific to each joint and
activity.
Flexibility exercises should be performed for each
joint in which increased flexibility is desired.
Chapter includes descriptions of static stretching
exercises for the:
neck
anterior hip and thigh
shoulder and upper chest groin area
upper back
posterior lower leg
lower back
foot and ankle
trunk
posterior hip, upper leg, and lower back
©2013, The McGraw-Hill Companies, Inc. All Rights Reserved
12-30