Chapter 10
Assessing Flexibility
Basics of Flexibility
• Flexibility is the ability of a joint, or series of joints, to
move through a full range of motion (ROM) without
injury.
• Flexibility and joint stability are highly dependent on
o joint structure and
o strength and number of ligaments and muscles spanning the
joint.
• Static flexibility is a measure of total ROM at the
joint, limited by the extensibility of the
musculotendinous unit.
• Dynamic flexibility is a measure of the rate of torque
or resistance developed during stretching
throughout the ROM. (Although dynamic flexibility accounts
for 44% to 66% of the variance in static flexibility)
Definitions and Nature of
Flexibility (continued)
• ROM is highly specific to the joint and
depends on morphological factors
such as the following:
o
o
o
o
o
joint geometry
joint capsule
ligaments
tendons
muscles spanning the joint
Definitions and Nature of
Flexibility (continued)
• Relative contribution of soft tissues to total
resistance encountered by the joint during
movement:
o
o
o
o
Joint capsule—47%
Muscle and its fascia—41%
Tendons and ligaments—10%
Skin—2%
• The joint structure determines the planes of motion
and may limit the ROM at a given joint. Triaxial
joints (e.g., ball-and-socket joints of the hip and
shoulder) afford a greater degree of movement in
more directions than nonaxial, uniaxial or biaxial
joints (see table 10., p 266).
Definitions and Nature of
Flexibility (continued)
• Tension in the muscle–tendon unit affects both
static (ROM) and dynamic flexibility (stiffness or
resistance to movement):
o viscoelastic properties - The tension within the muscle–tendon unit
affects both static flexibility (ROM) and dynamic flexibility (stiffness or
resistance to movement). The tension within this unit is attributed to the
viscoelastic properties of connective tissues, as well as to the degree of
muscular contraction resulting from the stretch reflex. Because tissues of
the body exhibit both elastic and viscous properties, they are called
“viscoelastic”.
o elastic deformation - The deformation that occurs as force is applied
and removed is called “elastic” deformation. The elastic deformation of
the muscle–tendon unit during stretching is proportional to the load or
tension applied.
o viscous deformation - The deformation that occurs after force
application or removal is called “viscous” deformation
o stress relaxation - When the muscle and tendon are stretched and held
at a fixed length (e.g., during static stretching), the tension within the
unit, or tensile stress, decreases over time.
Factors Affecting
Flexibility
• Hypertrophied muscles and excess subcutaneous fat may
impede flexibility.
• Static flexibility progressively decreases as muscle stiffness
increases with aging.
• Females are generally more flexible than males, regardless of
age; may be joint-specific. The greater flexibility of women is
usually attributed to gender differences in pelvic structure
and hormones that may affect connective tissue laxity. ROM
appears to be joint and motion specific, males have greater
ROM in hip extension and spinal flexion and extension in the
thoracolumbar region
• Lack of physical activity is a major cause of inflexibility.
• Active warm-up combined with static stretching is more
effective than static stretching alone. (when you administer
flexibility (ROM) tests, make certain that your clients warm up and statically
stretch the muscle groups before you measure them, and administer
multiple trials for each test item.)
Assessment of Flexibility
• Dynamic flexibility tests measure the increase in resistance
during muscle elongation; several studies have shown that
less stiff muscles are more effective in using the elastic
energy during movements involving the stretch–shortening
cycle However, dynamic testing is difficult and expensive to
assess
• Static flexibility assessed in field and clinical settings by direct
or indirect measurement of ROM. To assess static flexibility
directly, measure the amount of joint rotation in degrees
using a goniometer, flexometer, or inclinometer. To assess
flexibility indirectly ( as in low back / hamstring flexibility) you
can use various forms of sit and reach tests and skin
distraction tests
General Guidelines for
Flexibility Testing
• Have client perform general warm-up followed by
static stretching prior to the test.
• Avoid fast, jerky movements, and stretching to the
point of pain.
• Administer three trials of each test item.
• Compare client’s best score to norms to obtain a
flexibility rating for each test item.
• Use the test results to identify joints and muscle
groups in need of improvement.
Measuring Static
Flexibility (see photos in text pp. 268-272)
• Goniometer: protractor-like device with two steel
or plastic arms that measure the joint angle at the
extremes of the ROM
• Flexometer: consists of a weighted 360° dial and
weighted pointer
• Inclinometer: measures the angle between the
long axis of the moving segment and the line of
gravity
Goniometry
1. Place the center of the instrument so it coincides
with the fulcrum, or axis of rotation, of the joint.
2. Align the arms of the goniometer with bony
landmarks along the longitudinal axis of each
moving body segment.
3. Measure the ROM as the difference between the
joint angles (degrees) at the extremes of the
movement.
4. Follow standard procedures by joint. (see Table 10.2,
pp. 269-270, and slides that follow)
See Photo Examples next slides
Figure 10.1a
Figure 10.1b
Table 10.2
Table 10.2
Table 10.2 (continued)
Flexometer Test
Procedures
1. Strap the instrument to the body segment.
2. Lock the dial at 0° at one extreme of the ROM.
3. After the client executes the movement, lock the
pointer at the other extreme of the ROM.
4. The degree of arc through which the movement
takes place is read directly from the dial.
See photo examples next slides
Figure 10.2a
Figure 10.2b
Inclinometer Test
Procedures
•
•
•
•
•
Easier to use than the flexometer and universal goniometer
The inclinometer is another type of gravity-dependent
goniometer (see figure 10.3). To use this device, hold it on
the distal end of the body segment. The inclinometer
measures the angle between the long axis of the moving
segment and the line of gravity.
Held by hand on the moving body segment during the
measurement
Alignment with specific bony landmarks not required
American Medical Association recommends the doubleinclinometer technique to measure spinal mobility.
See photo examples next slides
Figure 10.3a
Figure 10.3b
Validity and Reliability of
Direct Measures
•
•
•
•
Highly dependent on the joint being measured
and technician skill
High agreement between ROM measured by
radiographs ( Radiography is considered to be the best reference method
for establishing validity of goniometric measurements.) and universal
goniometers for the hip and knee joints
No difference between radiography and the
double-inclinometer technique for assessing
spinal ROM of patients with low back pain
Inclinometer reliably measures ROM at most joints
Validity and Reliability of
Direct Measures (continued)
•
•
Intra-and inter-tester reliability of goniometric
measurements affected by identification of axis
of rotation and palpating bony landmarks
For inclinometer:
o
o
o
Inter-tester reliability is variable and joint specific. Studies have
reported reliability coefficients ranging from 0.48 for lumbar extension
to 0.96 for subtalar joint position.
Intra-rater reliabilities of flexibility during hip adduction and for ROM
measurements of the lumbar spine and lordosis generally exceed 0.90.
In order to obtain accurate and reliable ROM measurements, you
need a thorough knowledge of anatomy and of standardized testing
procedures, and training / practice to develop measurement
techniques.
Validity and Reliability of
Indirect Measures
•
Modified sit-and-reach test to evaluate the static
flexibility of the lower back and hamstring
muscles:
o
o
o
o
o
These tests are moderately related to hamstring flexibility (r = 0.39 to
0.89)
The sit-and-reach test has poor criterion-related validity and is
unrelated to self-reported low back pain.
Researchers concluded that standard fitness test batteries should
include measures of lumbar ROM instead of the sit-and-reach test to
assess low back fitness.
Lumbar ROM in the sagittal plane can be measured directly with an
inclinometer (double-inclinometer technique, see figure 10.3) or
indirectly with the skin distraction test
Although research affirms that the sit-and-reach test does not validly
measure low back flexibility, it may still be used to provide an indirect
measure of hamstring length, thus it may be used to assess these
changes
Indirect Methods of
Measuring Static Flexibility
•
Sit-and-reach test to evaluate the static flexibility
of the lower back and hamstring muscles
o
o
o
provides an indirect, linear measurement of the ROM.
is moderately related to hamstring flexibility, but poorly related to low
back flexibility.
has poor criterion-related validity and is unrelated to self-reported low
back pain.
Standard Sit-and-Reach
Test
•
•
•
•
Client sits on the floor with knees extended and
the soles of feet against the box edge.
Client keeps knees fully extended, arms evenly
stretched, and hands parallel with the palms
down (fingertips may overlap).
Client slowly reaches forward as far as possible
along the top of the box and holds this position
for two seconds.
Client’s score is the most distant point along the
top of the box that the fingertips contact.
Tips for Standard Sit-andReach Test
•
•
•
•
•
•
Have client warm up prior to test.
Advise your client that lowering the head and
exhaling during the stretch maximizes the distance
reached.
If the client’s knees are flexed, motion is jerky or
bouncing, or fingertips do not maintain contact with
the slider, do not count that score.
Administer two trials and record the maximum score
to the nearest 0.5 cm.
Use box with zero point at 26 cm.
Interpret using gender-specific results. (see next slide)
Table 10.4
V Sit-and-Reach Test
•
•
•
•
•
Secure a yardstick to the floor by placing tape (12 in.
long) at a right angle to the 15-inch mark on the
yardstick.
Client sits on floor, straddling the yardstick with knees
extended, heels of feet on 15-inch mark and 1 foot
apart.
Client reaches forward slowly, as far as possible, along
the yardstick while keeping the hands parallel.
Client holds position about two seconds.
The score (in centimeters or inches) is the farthest
point on the yardstick contacted by the fingertips.
Tips for V Sit-and-Reach
Test
•
•
•
Don’t have client lock knees in extended position
at start.
Make certain that the knees do not flex and that
the client avoids leading with one hand.
Interpret the score using gender-specific
normative values. (see next slide)
Table 10.5
Modified Sit-and-Reach
Test (see photos in sequential slides)
•
•
•
•
Client sits on the floor with buttocks, shoulders,
and head in contact with the wall.
Client extends the knees and places the soles of
the feet against the sides of box.
Place a yardstick on top of the box with the zero
end toward the client.
Client reaches forward with one hand on top of
the other while keeping the head and shoulders
in contact with the wall.
Modified Sit-and-Reach
Test (continued)
•
•
•
Yardstick is positioned so that it touches the
fingertips; this establishes the zero point for each
client.
As you firmly hold the yardstick in place, client
reaches forward slowly, sliding the fingers along
the top of the yardstick.
The score (in inches) is the most distant point on
the yardstick contacted by the fingertips.
Tips for Modified Sit-andReach Test
•
•
•
•
•
•
•
Use this test for those with long arms and short
legs.
Don’t have client lock knees in extended position
at start.
Make certain that the knees do not flex and that
the client avoids leading with one hand.
Have client hold stretch for two seconds.
Record the higher of two measures.
Avoid fast, jerky movements.
Interpret the score using gender-specific norms.
Figure 10.4a
Figure 10.4b
Table 10.6
Back-Saver Sit-and-Reach
Test (see photo in sequential slide)
•
•
•
•
Client places the sole of the foot of the extended
(tested) leg against the edge of the sit-and-reach
box.
Client places the foot of the untested leg flat on
the floor 2 to 3 inches to the side of the extended
(tested) knee.
Remainder of instructions are the same as for the
standard sit-and-reach test.
Determine client’s flexibility score for each leg.
Figure 10.5
Modified Back-Saver Sitand-Reach Test
(see photo in sequential slide)
•
•
•
•
Client performs a single-leg sit-and-reach on a 12inch bench.
Client places the untested leg on the floor with
the knee flexed at a 90° angle.
Align the sole of the foot of the tested leg with
the 50-cm mark on the meter rule.
Follow instructions for the standard sit-and-reach
test to determine your client’s hamstring flexibility
for each leg.
Tips for Modified BackSaver Sit-and-Reach Test
•
•
•
•
•
•
Have client warm up prior to test.
Be sure zero point of meter stick or tape measure is
pointing toward client.
Secure the meter stick or tape measure to the table.
Advise your client that lowering the head and
exhaling during the stretch maximizes the distance
reached.
If the client’s test-leg knee is flexed, motion is jerky or
bouncing, or fingertips do not remain aligned, do not
count that score.
Administer two trials and record the maximum score
to the nearest 0.5 cm.
Figure 10.6
Skin Distraction Test
(see photos in
sequential slides)
•
•
•
•
•
Place a 0 cm mark on the midline of the lumbar
spine at the intersection of a horizontal line
connecting the left and right posterior superior
iliac spines while the client stands erect.
Place a second mark 15 cm superior to the 0 cm
mark.
Instruct the client to bend forward at the waist as
far as possible.
Measure the new distance (cm) between the
two marks.
Record the score as new distance minus 15 cm.
Figure 10.7a
Figure 10.7b
Lumbar Stability Tests
Lumbar instability increases the risk of developing
low back pain. The primary muscle groups
responsible for stabilizing the lumbar spine are the
trunk extensors (erector spinae), trunk flexors
(rectus abdominis and abdominal oblique
muscles), and lateral flexors (quadratus
lumborum).
• Use these 3 tests to evaluate the balance in the
isometric endurance capabilities of back muscles
in healthy individuals:
•
o
o
o
Trunk extension
Trunk flexion
Side bridge
Trunk Extension
•
•
•
•
Client lies prone with the lower body secured to
the test bed at 3 places and with the upper body
extended over the edge of the bed (bed is 10
inches from floor).
Client holds arms across chest, hands resting on
opposite shoulders.
Client assumes and maintains horizontal position
above the floor for as long as possible.
Record time (in seconds) client maintains the
horizontal position; trial ends when upper body
contacts the floor.
Trunk Flexors
• Client sits on a test bench with a moveable back
support set at a 60° angle.
• Client flexes the knees and hips to 90° and folds
the arms across the chest.
• Use toe straps to secure client’s feet to the test
bench.
• Record time (in seconds) client maintains this body
position after you lower or remove the back
support.
• Stop stopwatch when client’s trunk falls below the
60° angle.
Side Bridge
• Have client assume a side-lying position on a mat, legs
extended.
• Have client place top foot in front of the lower foot for
support.
• Instruct client to lift hips off mat while supporting the
body in a straight line on one elbow and the feet for as
long as possible.
• Keep the uninvolved arm across the chest.
• End the test when hips return to the mat.
• Use a stopwatch to record elapsed time (in seconds).
• Administer test for both right and left sides of the body.
Flexibility Testing of Older
Adults
• Chair sit-and-reach test:
o Position folding chair against a wall.
o Client sits on front edge of the seat.
o Client extends test leg in front of the hip, heel on floor,
ankle dorsiflexed ~90°, knee extended.
o Sole of other foot is flat on the floor about 6 to 12 inches to
side of the body’s midline.
o With hands overlapped (palms down), client bends
forward at hip, keeping spine straight and head in normal
alignment with spine.
o Client tries to touch toes of test leg, holding position for
two seconds.
o Administer two practice trials followed by two test trials.
Flexibility Testing of Older
Adults (see photo in sequential slide)
• Many older individuals have difficulty performing sitand-reach tests because functional limitations
(e.g., low back pain and poor ROM) prevent them
from getting down to and up from the floor.
• The chair sit-and-reach test is similar to the backsaver protocol (see figure 10.6) in that it tests only
one leg, thereby reducing stress on the spine and
lower back.
Flexibility Testing of Older
Adults (see photo in sequential slide)
• Chair sit-and-reach test:
o Position folding chair against a wall.
o Client sits on front edge of the seat.
o Client extends test leg in front of the hip, heel on floor,
ankle dorsiflexed ~90°, knee extended.
o Sole of other foot is flat on the floor about 6 to 12 inches to
side of the body’s midline.
o With hands overlapped (palms down), client bends
forward at hip, keeping spine straight and head in normal
alignment with spine.
o Client tries to touch toes of test leg, holding position for
two seconds.
o Administer two practice trials followed by two test trials.
Flexibility Testing of
Older Adults (continued)
• Scoring chair sit-and-reach test:
o Place ruler parallel to the lower leg; the zero point is the
middle of the big toe (medial aspect) at the end of the
shoe.
o Reaches short of toes are recorded as minus scores;
reaches beyond toes are recorded as plus scores.
o Record best score to the nearest 0.5 inch.
o Interpret score through normative values.
Figure 10.8
Table 10.8
Flexibility Testing of
Older Adults (continued)
• Back scratch test: (see photo in sequential
slide)
o Client reaches, with preferred hand (palm down and
fingers extended), over the shoulder and down the back.
o Client simultaneously reaches around and up the middle
of the back with the other hand (palm up and fingers
extended).
o Allow the client to choose the best, or preferred, hand
through trial and error.
o Administer 2 practice trials followed by 2 test trials.
Flexibility Testing of
Older Adults (continued)
• Scoring back scratch test:
o Use ruler to measure overlap (plus score) or gap (minus
score) between middle fingers of each hand.
o If fingers just touch each other, record a zero.
o Record best score to the nearest 0.5 inch.
o Compare this value to the gender-specific norms.
Figure 10.9
Table 10.9
End of Presentation