Flexibility
Learning Targets
• I can define flexibility and the things that limit
Range of Motion
• I can explain the agonist/antagonist relationship
between muscles
• I can compare and contrast the 5 different
stretching techniques
• I can describe how to perform the 3 different PNF
techniques
• I can explain the neurophysiological basis for
flexibility and stretching as it applies to each
stretching technique
Flexibility Defined
• Flexibility: the ability to move a
joint or series of joints through a
full, nonrestricted, pain-free
range of motion
• Can be discussed in relation to a
single joint or a series of joints
• Restricted range of motion can
decrease performance
capabilities
– E.g. losing speed because
hamstrings restrict hip flexion
decreasing stride length; awkward
or uncoordinated movement
patterns
Factors that Limit Flexibility
• Elasticity: tissue’s ability to
return to its resting length
• Extensibility: ability to
stretch beyond a tissue’s
normal length
• Bony structure
• Fat
• Skin
• Muscles and tendons
• Connective
tissue/contractures
– Lose elasticity and shorten
when immobilized
Active ROM
• Active ROM (also called
Dynamic Flexibility)
– Degree which a joint can be
moved by a muscle contraction
– Not a good indicator of
flexibility because it applies to
the ability to move a joint
efficiently, with little resistance
to motion.
– Required to perform sporting
activities
• Need full knee extension to
hurdle and for full stride
length
Passive ROM
• Passive ROM (also called Static
Flexibility)
– Degree which a joint can be
passively moved to the
endpoints in the ROM.
– No muscle contraction is
involved.
– Can move farther than active
ROM
– Important for injury
prevention; allows muscle to
stretch to prevent injury to the
musculotendinous unit
Goniometry
• Goniometer
• A large protractor with
measurement in degrees
• Align individual arms of
goniometer parallel with
the longitudinal axis of the
two segments involved in
motion about a specific
joint.
Stretching Techniques
• Flexibility is important for
successful physical
performance and injury
prevention
• Goal of a flexibility
program is to improve
ROM at given articulation
by altering extensibility of
the musculotendinous
unit that produce
movement at that joint.
Stretching Techniques
• Agonist v. Antagonist
Muscles (Hero v. Villian)
• Muscles that perform a
specific action are called
agonist muscles (e.g. quads
perform knee extension)
• Muscles that are being
stretched in response to the
contraction of the agonist
are antagonist muscles (e.g.
hamstrings stretched in
knee extension)
Stretching Techniques
• Muscles that work in
concert with one another
are called synergistic
muscle groups (e.g. all
four quadriceps muscles)
• Balance must exist
between agonist and
antagonist muscles to
allow for coordinated
movement, as well as
reduce the chance of
muscle strain or
imbalances.
Stretching Techniques: Ballistic
• Ballistic Stretching
– Bouncing movements;
repetitive contractions of
the agonist muscle are
used to produce quick
stretches of the antagonist
muscle.
– Concern that somewhat
uncontrolled forces within
the muscle may exceed
extensibility limits in the
muscle fiber, thus
producing small microtears
in the musculotendinous
unit.
Stretching Techniques: Ballistic
– May be true in sedentary or
athletes with muscular injury
but not usually a concern in
healthy athletes.
– Most sports are dynamic and
require ballistic movements
• e.g. forcefully kicking a soccer
ball 50 times requires
contraction of the quadriceps
to extend the knee and
requires the hamstrings to
decelerate the lower leg via
eccentric contractions. Ballistic
stretching would prepare the
hamstrings for this type of
activity.
Stretching Techniques
• Static Stretching
– Involves passive stretching of
the antagonist by placing it in
a maximal position and
holding it for an extended
period of time.
– Research has shown that
holding a static stretch for 15
seconds is as effective as
holding it for 2 minutes.
– Research indicates that for
maximal effectiveness over
time static stretches should
be repeated 3-5 times for
each muscle being stretched.
Stretching Techniques
• Static Stretching (continued)
– Can be accomplished by using a
contraction of the agonist
muscle, body weight, a partner,
or a T-bar or pole (primarily for
upper body)
– Research has shown that static
and ballistic stretching are
equally effective for improving
flexibility, however there seems
to be less danger of exceeding
extensibility limits with static
stretching.
– Ballistic stretching is better
indicated as part of a warm-up
as it more mimics dynamic
activity.
Stretching Techniques
• Proprioceptive
Neuromuscular Facilitation
– Techniques called slowreversal-hold-relax, contractrelax, and hold-relax
– Utilize isotonic and isometric
contractions and relaxation of
both agonist and antagonistic
muscles
– Best with a partner but can
be used with a wall for
resistance.
Neurophysiological Basis of Stretching
• All three techniques
involve the
neurophysiological
phenomenon involving
the stretch reflex.
• Mechanoreceptors
send messages to the
CNS of what is
happening to the
muscle.
• Two of the
mechanoreceptors that
are important in the
stretch reflex are the
muscle spindle and
Golgi tendon organ.
Muscle Spindle
• Sensitive to changes in muscle
length.
• When a muscle is stretched
sensory impulses are sent to
the CNS informing it that the
muscle is being stretched.
• Return impulses from the
spinal cord to the muscle
causing the muscle to
reflexively contract, thus
resisting the stretch.
• If the stretch continues for at
least 6 seconds the Golgi
Tendon Organ responds.
Golgi Tendon Organ
• Affected by changes in
muscle length and muscle
tension.
• If the stretch continues for
at least 6 seconds the Golgi
Tendon Organ responds by
causing a reflex relaxation
of the antagonist muscle
• This protects the muscle
and allows it to stretch
through relaxation before
extensibility limits are
exceeded.
Neurophysiology Applied
• Ballistic Stretching
– Repetitive bouncing repeatedly stretch the Muscle
Spindles
– Ballistic stretching is not held long enough to allow the
GTO to have a relaxing effect.
– This stretching targets other tissues to help improve ROM
• Static Stretching
– Involves sustained stretch lasting from 6-60 seconds
– This allows the GTO to respond to increased tension
– GTO overrides impulses from Muscle Spindle allowing the
muscle to relax.
Neurophysiology Applied
•
PNF
– It takes advantage of the same
neurophysiological principles and two
additional techniques.
Autogenic Inhibition
• A maximal isometric contraction of
the muscle that will be stretched
during a 10 second “push” phase
increases tension that stimulates the
GTO
• This causes a reflexive relaxation
response in the antagonist muscle
even before it is placed into a
stretched position
• Relaxation of the antagonist muscle
during contractions is referred to as
autogenic inhibition
Neurophysiology Applied
Reciprocal Inhibition
• In any synergistic muscle
group, a contraction of the
agonist causes a reflex
relaxation of the antagonist
muscle.
• An additional passive stretch
during the isometric
contraction of the agonist
pulling the extremity further
into the agonist pattern elicits
an additional relaxation reflex
of the antagonist muscle.
– This is called reciprocal
inhibition.
PNF: Contract-Relax Technique
Contract-Relax
• Start with a Passive Stretch for
15 seconds
Repeat the following pattern3-5
times ending on passive stretch:
• Verbal Command “Push”
contracting the antagonist
muscle being stretched for 10
seconds
• Verbal Command “Relax” and
move into a deeper passive
stretch
• Repeat 3-5 times ending on
passive stretch for 10-15
seconds
PNF: Hold-Relax Technique
Hold-Relax
• Start with a Passive Stretch
for 15 seconds
Repeat the following pattern35 times ending on passive
stretch:
• Verbal Command “Pull”
contracting the agonist
muscle for 10 seconds
• Verbal Command “Relax”
and move into a deeper
passive stretch for 10-15
seconds
PNF: Slow Reversal-Hold-Relax
Technique
Contract-Hold-Relax
• Start with a Passive Stretch
for 15 seconds
Repeat the following pattern35 times ending on passive
stretch:
• Verbal Command “Push”
contracting the antagonist
muscle being stretched for
10 seconds
• Verbal Command “Pull”
contracting the agonist
muscle for 10 seconds
• Verbal Command “Relax”
and move into a deeper
passive stretch for 10-15
seconds
Guidelines and Precautions for
Stretching
Warm-up
• low intensity to high
• large gross motor movements to
sports specific
• multi joint
Why
• increase blood flow
• increase body temp
• increase extensibility
• increase respiration/O2 intake
• lubricate joints
• increase heart rate
• remove waste
• increase mental acuity
• excite nervous system
Guidelines and Precautions for
Stretching
• To increase flexibility, a muscle
must be overloaded and
stretched beyond its normal
ROM but not to the point of
pain.
• Stretch only to the point of
tightness or resistance; NO
PAIN!
• Increases ROM will be specific
to whatever muscle or joint is
being stretched.
• Be careful when stretching
painful joints. Pain is the
body’s way of letting you know
something is wrong.
Guidelines and Precautions for
Stretching
• Avoid overstretching
• Exercise caution when
stretching the neck and low
back. Exercises that
compress the vertebrae and
discs can cause damage.
• To reduce stress on the low
back, stretch in a seated
position
• Stretch muscles that are
tight and inflexible
• Strengthen loose muscles
Guidelines and Precautions for
Stretching
• Apply stretches that are
appropriate to the
person and/or activity.
• Breathe normally
• Should be done at least
3 times/week for
minimal improvement;
5-6 times/week for
maximal improvement