1. Restoring Range of Motion and Improving Flexibility

2. Importance of Flexibility
Important Goal: Restore or improve to normal pre-injury range of motion
With injury there is generally some degree of lost range of motion
Due to pain, swelling, muscle guarding, &/or inactivity resulting in tissue shortening
Need to encourage stretching exercises
Restricted range of motion can impact performance & result in uncoordinated motion
Essential for successful physical performance & injury prevention

3. Flexibility
Ability of neuromuscular system to allow for efficient movement of a joint or series of joint through a full, non-restricted pain free range of motion

4. Anatomic Factors Impacting Flexibility
Muscles
Increasing flexibility relies on the elastic properties of muscle
Length can be changed over time
Connective Tissue
Ligaments & joint capsules, while possessing some elastic properties, can lose their elasticity during periods of disuse & immobilization
Bony Structures
Can limit end point range
Bony prominences can also stop movements at normal end points in the range
Fat
Can act as a wedge between lever arms
Restricts movement wherever it is found

5. Skin
Injury or surgical procedure may alter skin – variable in elasticity
Skin adheres to underlying tissue
Neural tissue
Develops tightness as a result of compression, chronic repetitive microtrauma, muscle imbalances, joint dysfunction or morphological adaptations due to posture
Could stimulate nociceptors & pain
Cause muscle guarding & spasm to protect irritated neural structures
Neural fibrosis ultimately results causing decreased elasticity & restricted motion
Except for bone structure, age & gender all other flexibility limiting factors can be modified & altered to increase range of motion

6. Soft Tissue Properties that Affect Immobilization & Elongation
Responses that affect soft tissue during stretching
Velocity, intensity, frequency & duration of stretch force
Temperature of tissues
Elasticity – ability of soft tissue to return to its resting length after passive stretch
Plasticity – tendency of soft tissue to assume a new & greater length after stretch force has been removed

7. Soft Tissue Properties that Affect Immobilization & Elongation
Contractile tissue: gives muscle characteristics of contractility & irritability
Noncontractile tissue: has same properties as all CT, including ability to resist deforming forces as well as viscoelasticity
CT structures of muscle-tendon unit
Epimysium – enveloping fascial sheath
Perimysium – encases bundles of fasciculi
Endomysium – innermost layer that separates individual m. fibers & myofibrils

8. CT Structures of Muscle-tendon Unit

9. Muscle Anatomy
Made up of many muscle fibers that lie parallel with one another
Single fiber – made up of many myofibrils
Myofibrils - composed of sarcomeres
Sarcomere – contractile unit of the myofibril
Gives muscle ability to contract & relax
Composed of overlapping myofilaments of Actin & Myosin (form cross-bridges)
Motor unit stimulated = m. contraction -actin-myosin filaments slide together & the muscle actively shortens
Muscle relaxes = cross-bridges slide apart slightly & the muscle returns to its resting length

10. Muscle Anatomy

11. Muscle Structure

12. Myofilament Interlocking Mesh Structure
A myofilament shows several distinct bands
Each band has been given a special letter
The lightest (least electron dense) band is the “I band”
Consists primarily of actin
In the center of the “I band” is the “Z-line”, an electron dense line
The wide, dark band is the “A band”
Consists primarily of myosin
In the middle of the “A band” is the “M line”, another dense line

13. Myofilament Sliding

14. Noncontractile Tissue
Made up of:
Collagen – resist tensile deformation & are responsible for strength & stiffness of tissue, elongates quickly under light loads
Elastin - extensibility
Reticulin fibers – bulk
Ground substance – proteoglycans (PGs) & glycoproteins;
PGs hydrate matrix, stabilize collagen network, resist compressive forces;
Glycoproteins provide linkage between matrix components & between cells & matrix opponents
Mechanical behavior is determined by proportion of collagen & elastin fibers & structural orientation of the fibers
High collagen, low PGs – resist high tensile loads
High collagen content tissue = greater stability (tendons)

15. Active & Passive Range of Motion
Active range of motion (AROM)
Dynamic flexibility
Joint movement via muscle contraction
Ability to move a joint with little resistance
Passive range of motion (PROM)
Static flexibility
Motion of joint to end points without muscle contraction
Critical in injury prevention
Muscles can be forced to stretch beyond “normal” limits
Without elasticity it is likely that the musculotendinous unit will be injured
During athletic activity
Must be able to move through unrestricted range
Must have elasticity for additional stretch encountered during activity

16. Measuring Range of Motion
Essential to assess improvement during rehabilitation
Goniometer
Utilizes alignment of two arms parallel to longitudinal axis of two segments involved in motion
Relatively accurate tool
Ensures accuracy standardize techniques & methods of recording AROM & PROM

17. Agonist vs. Antagonist Muscles
Joints are capable of multiple movements
Example:
Quadriceps will extend knee with contraction
Quads (muscle producing movement) = agonist
Hamstrings will stretch during knee extension
Hamstrings undergoing stretch = antagonist
Agonist & antagonist work together to produce smooth coordinated movements
Muscles that work together function synergistically
What is another pair of agonist/antagonist muscles?

18. Stretching Techniques
Ballistic
Bouncing movement in which repetitive contractions of agonist work to stretch antagonist muscle
Static stretching
Stretch to point of discomfort & holding at that point for period of time
Proprioceptive Neuromuscular Facilitation (PNF)
Involves alternating contractions & stretches
Myofascial & neural tissue stretching
Enhances neuromuscular system’s ability to control movement

19. Ballistic Stretching Need to be careful when performing this stretch
Possible soreness due to uncontrolled forces within muscle created by bouncing
May result in tissue damage
Should be incorporated into a program to allow body to adapt & reduce likelihood of injury
Incorporate into later stages of rehabilitation

20. Static Stretching Passively stretching given antagonist
6-8 second hold in maximal position of stretch
Go to point of discomfort & back off slightly
Hold for seconds (do this 3-4 times)
Can be accomplished utilizing agonist
Controlled movement, less chance of injury

21. Proprioceptive Neuromuscular Facilitation
Three techniques that combine alternating isometric or isotonic contractions & relaxation of both agonist & antagonists
Slow-reversal-hold-relax
Contract-relax
Hold-relax
Hold Relax (HR)
Isometric contraction of antagonist followed by concentric contraction of agonist with light pressure
Facilitates stretch of antagonist
Effective with muscle tension on one side of joint

22. Slow Reversal-Hold-Relax (SRHR)
Contract Relax (CR)
Moves body passively into agonist pattern
Athlete instructed to contract antagonist isotonically against resistance
Athlete then relaxes & allow athletic trainer to push body further (passively) into agonist pattern
Utilized when flexibility is limited due to muscle tightness
Slow Reversal-Hold-Relax (SRHR)
Isotonic contraction of agonist
Follow with isometric contraction of antagonist
During relax phase antagonist is relaxed while agonist contracts in agonist pattern
Results in stretch of antagonist
Useful to stretch antagonist

23. Comparing Stretching Techniques
Ballistic stretching is recommended for athletes engaged in dynamic activity
Static stretching most widely used
Safe & effective
PNF techniques
Capable of producing dramatic increases in ROM
Limitation – partner is required
Maintaining flexibility
Can decrease considerable after only 2 weeks
Should be engaged in at least once per week

24. Specific Stretching Exercises

25. Stretching Neural Structures
Requires differentiation between musculotendinous & neural tightness
Assess movements that create tension in neural structures
May cause numbness & tingling
Straight-leg raise example

26. Myofascial Release Stretching
Techniques used to relieve abnormally tight fascia
Myofascial restrictions are unpredictable & may occur in different planes & directions
Requires specialized training & in depth understanding of fascial system
Fascia
Connective tissue that runs throughout the body & establishes interconnectedness of body
If altered or injured can result in localized response at focal point of injury or away from injury site
Responds to gentle pressure

27. Sometimes called: Soft-tissue Mobilization Treatment
Localize restriction
Considerably more subjective component & relies heavily on clinician’s experience
Focuses on large treatment area
Work superficial to deep
Joint mobilizations may follow
Tissue stretching & elongation as well as strengthening should follow
Postural re-training may also be required
Dramatic results may occur
Treatment should be done at least 3 times per week
Perform manually or via foam roller

29. Neurophysiological Basis of Stretching
Stretch Reflex
Muscle is placed on stretch – muscle spindle
Muscle spindles fire relaying info. to spinal cord
Spinal cord relays message to golgi tendon & increases tension
After 6 seconds, golgi tendon organ (GTO) relays signal for muscle tension to decrease
Cause reflex relaxation
Prevents injury - protective mechanism
Ballistic stretching does not allow this overriding response by GTO

30. PNF benefits greatly from these principles
With static stretching GTO’s are able to override impulses from muscle spindle following initial reflex resistance
Allows muscle to remain stretched without injury
PNF benefits greatly from these principles
With slow-reversal hold technique, maximal contraction of muscle stimulates GTO reflex relaxation before stretch applied

31. Reciprocal inhibition
Autogenic inhibition
Relaxation of antagonist during contraction
During relaxation phase, antagonist is placed under stretch but assisted by agonist contraction to pull further into stretch
GTO is protective mechanism that inhibits tension in the muscle
Reciprocal inhibition
Isotonic contraction of an agonist muscle elicits a reflex relaxation of antagonist muscle group - (protect against injury)

32. Effect of Stretching on Physical & Mechanical Properties of Muscle
Physical lengthening of muscle occurs due to reflex relaxation
Contractile & non-contractile elements of muscle dictate capability of deformation & recovery
Both resist deformation
Deformation is dependent on degree of stretch & velocity
Non-contractile – limit degree
Contractile – limit velocity
Greater stretch = more non-contractile components contribute

33. Stretches sustained long enough (autogenic inhibition) result in viscoelastic & plastic changes in collagen & elastin
Viscoelastic changes allow slow deformation & imperfect recovery (not permanent)
Plastic changes result in permanent changes in length
Greater velocity = greater chance for exceeding tissue capacity (viscoelastic & plastic)

34. Effects of Stretching On Kinetic Chain
Joint hypomobility causes:
Faulty posture
Muscular imbalance
Abnormal neuromuscular control
Alteration in arthrokinematics
Change in muscle tension to reduce translation
Alters degrees of tension & activation in synergist, stabilizers & neutralizers
Compensatory response

35. Muscle Tightness & Hypertonicity
Impact on length-tension relationships
Alters force couples & arthrokinematics
Impacts normal force couple relationships & creates kinetic chain reaction
Impacts synergistic function of kinetic chain
Causes abnormal joint & tissue stresses, neural compromise & vascular/lymphatic stasis
Alters recruitment strategies & stabilization
Alters neuromuscular efficiency impacting activation/firing sequence
Additionally altered joint function & stress response
Can causes reciprocal inhibition
Increases muscle spindle activity
May impart inhibitory response (decreased neuromuscular control)
Result = synergistic dominance – synergist compensatory action for weak & inhibited muscle

36. Importance of Warm-up Prior to Stretching
Intramuscular temperature should be increased prior to stretching
Positive effect on ability of collagen & elastin to deform
Enhances reflexive relaxation associated with golgi tendon organs
Optimal temperature 39oC/103oF
To increase = low intensity, warm-up type exercise or modalities
Exercise should be primary means of warm-up
Environment - Heat vs. Cold

37. Flexibility vs. Strength
Co-exist
Muscle bound
Negative connotation
Loss of motion
Encourage full pain free movements during rehabilitation
Strength training will provide individual with ability to develop dynamic flexibility through full range of motion
Develop more powerful & coordinated movements

38. Guidelines & Precautions for Stretching
Warm-up
Overload or stretch beyond normal range
Not to point of pain
Stretch to point of resistance
Increases in range will be specific to muscle being stretched
Use caution when stretching around painful joints
Avoid overstretching ligaments & capsules
Exercise caution with low back & neck stretches
Stretch from seated position to reduce stress on back
Continue normal breathing while stretching
For improvements in ROM, utilize static & PNF stretching techniques
Ballistic stretching should be used by those who possess flexibility & are accustomed to it
Ballistic stretching should follow period of static stretching
Stretching should be performed a minimum of 3 times per week
For maximum gains stretching 5-6 times per week is ideal