Flexibility

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Flexibility
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Flexibility

• Optimal musculoskeletal function requires that an
  adequate range of motion be maintained in all
  joints.

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Flexibility

• Identify those joints and muscle groups which are
  in need of improvement and select an appropriate
  exercise mode and specific exercises for the
  flexibility program.

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Flexibility

• The specificity and progressive overload
  principles apply to the design of flexibility
  programs.

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Flexibility

• Flexibility is highly joint-specific therefore,
  to increase flexibility of a particular joint,
  select exercises that stretch the appropriate
  muscle groups.

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Flexibility

• To improve ROM at the joint, your client must
  overload the muscle group by stretching the
  muscles beyond their normal resting length - but
  never beyond the pain-free range of motion.

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Flexibility

• Periodically your client will need to increase
  both the amount of time the stretched position is
  maintained and the number of repetitions of the
  exercise to ensure the overload required for
  further improvement.

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Flexibility

• Of particular importance is maintenance of
  flexibility in the lower back and posterior thigh
  regions.
• See next set of notes on back health.

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Flexibility

• Lack of flexibility in this area may be
  associated with an increased risk for the
  development of chronic lower back pain.

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Flexibility

• Lack of flexibility is prevalent in the elderly
  among whom this condition often contributes to a
  reduced ability to perform activities of daily
  living (ADL).

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Flexibility

• Accordingly, exercise programs for the elderly
  should emphasize proper stretching, especially
  for the upper and lower trunk, neck, and hip
  regions.

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Flexibility

• There are different types of stretching
  techniques (e.g., static, ballistic, and PNF)
  that can be performed.

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Flexibility

• All three types of stretching are effective in
  increasing the ROM.

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PNF

• PNF stretching increases ROM by inducing muscle
  relaxation through spinal reflex mechanisms.

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PNF

• Using the contract-relax technique, your client
  first performs an isometric contraction of the
  muscle group being stretched, and then proceeds
  with the slow, static stretching (relaxation
  phase) of the muscle group.

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PNF

• This technique is based on the concept of
  reciprocal inhibition.
• Contraction on one muscle causes relaxation in
  another.

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PNF

• Theoretically, the isometric contraction of the
  antagonists (muscle group being stretched)
  induces a reflex facilitation and contraction of
  the agonist during the slow, static stretching
  phase.

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PNF

• The isometric contraction of the antagonists also
  stimulates the Golgi tendon organs, resulting in
  a reflex relaxation of the same muscle group.

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PNF

• Another type of PNF stretching is the
  contract-relax with agonist contraction (CRAC)
  technique.

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PNF

• This method is identical to the contract-relax
  technique except that the stretching is assisted
  by a submaximal contraction of the opposing
  (agonist) muscle group.

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PNF

• Theoretically, the voluntary contraction of the
  agonists induces additional inhibitory input to
  the antagonists (muscles being stretched) through
  reciprocal inhibition.

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Steps for PNF Stretching

• 1. Stretch the target muscle group by moving the
  joint to the end of its ROM.
• 2. Isometrically contract the pre-stretched
  muscle group against an immovable resistance
  (such as a partner or wall) for 5 to 6 seconds.

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Steps for PNF Stretching

• 3. Relax the contracted muscle group as you or
  your partner statically stretch the muscle to a
  new point of limitation.

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Steps for PNF Stretching

• 4. With the contract-relax agonist contraction
  technique, the opposing muscle group, (agonist)
  contracts submaximally for 5 to 6 seconds to
  facilitate relaxation and further stretching of
  the target muscle group.

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Static Stretching vs Ballistic Stretching

• Many exercise specialists recommend using slow,
  static stretching rather than ballistic
  stretching because there is more chance of injury
  and muscle soreness resulting from jerky, rapid
  movements.

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Static Stretching vs Ballistic Stretching

• The ballistic technique uses a relatively fast,
  bouncing motion to produce stretch.

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Static Stretching vs Ballistic Stretching

• The momentum of the moving body segment, rather
  than external force, pushes the joint beyond its
  present ROM.

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Static Stretching vs Ballistic Stretching

• This technique appears to be counterproductive
  for increasing muscle stretch.
• Muscle spindles signal both changes in length and
  speed of contraction.

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Static Stretching vs Ballistic Stretching

• The spindle responds more to the speed of
  movement than to the muscles length or position.
• In fact, muscle spindle activity is directly
  proportional to the speed of movement.

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Static Stretching vs Ballistic Stretching

• Thus, ballistic stretching evokes the stretch
  reflex, producing more contraction and resistance
  to stretch in the muscle group being stretched.

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Static Stretching vs Ballistic Stretching

• This places strain on the muscle-tendon unit and
  may cause microscopic tearing of muscle fibers
  and connective tissue.

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Static Stretching vs Ballistic Stretching

• In slow, static stretching, your client stretches
  the muscle with the joint positioned at the end
  of its ROM.

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Static Stretching vs Ballistic Stretching

• While maintaining this position, the client
  slowly applies torque to the muscle to stretch it
  further.
• Because the dynamic portion of the muscle spindle
  rapidly adapts to the lengthened position, the
  spindle discharge is decreased.

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Static Stretching vs Ballistic Stretching

• This lessens reflex contraction of the muscle and
  allows the muscle to relax (viscoelastic stress
  relaxation) and to be stretched even further.

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Is PNF stretching better than slow, static
stretching?

• Limited research.
• It may be, but it produces greater feelings of
  being uncomfortable.

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PNF Stretching vs Static Stretching

• A major disadvantage of the PNF technique is that
  the exercises, in some cases, cannot be performed
  alone.

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PNF Stretching vs Static Stretching

• A partner is needed to resist movement during the
  isometric contraction phase and to apply external
  force to the muscle during the stretching phase.

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PNF Stretching vs Static Stretching

• Thus, the amount of time required for both
  individuals to complete the flexibility exercises
  is increased.

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Comparison of Stretching Techniques

• See table 11.1, p. 284, Heyward Book

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Exercise Program for Flexibility

• A well-rounded program includes at least one
  exercise for each of the major muscle groups of
  the body.

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Exercise Program for Flexibility

• Use the results of the flexibility tests to
  identify specific muscle groups with relatively
  poor flexibility, and include more than one
  exercise for these muscle groups.

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Exercise Program for Flexibility

• A general exercise program for achieving and
  maintaining flexibility should adhere to the
  following guidelines

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Flexibility

• F At least 3 days/week, preferably daily.
• I To a position of mild discomfort.
• Slowly elongate to low force hold.
• T 15 to 30 secs. for each stretch.
• Not much improve beyond 30 secs.
• S 3 to 5 reps for each stretch. Perform static
  stretches and/or PNF with a major emphasis on the
  lower back and thigh area.

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Safe Intensity?

• The joint should not be stretched beyond its
  pain-free range of motion.
• Some mild discomfort will occur.

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Duration of Stretch?

• ACSM recommends holding the stretched position
  only as long as it feels comfortable (usually 15
  to 30 seconds).

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Number of Repetitions?

• Beginners should start with 3 reps of each
  exercise.
• As flexibility improves, they may increase the
  reps to 5.

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Flexibility

• Tips
• Perform in an unloaded body position.
• Stretch muscles, not ligaments.
• Focus on problem areas.
• Target normal static range of motion.
• Extreme stretching causes increased risk of
  injury.

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Flexibility

• Tips
• Emphasize active warm-up prior to stretching.
• Stretch during cool down.
• Focus on areas of increased static range of
  motion demand.

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Tips

• Focus on the target muscle involved in the
  stretch, relax the target muscle, and minimize
  the movement of other body parts.

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Tips

• Stretch to the limit (endpoint) of the movement,
  not to the point of pain.

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Tips

• Keep breathing slowly and rhythmically while
  holding the stretch.
• Stretch the target muscle groups in different
  planes to improve overall ROM at the joint.

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Risky Exercises?

• Hyperextension
• Hyperflexion