2. Stretching
• Stretching is a general term used to describe any
therapeutic maneuver designed to increase the
extensibility of soft tissues, thereby improving flexibility
and ROM by elongating (lengthening) structures that have
adaptively shortened and have become hypomobile over
time.
3. FLEXIBILTY
• Flexibility is the ability to move a single joint or series of
joint smoothly and easily through an unrestricted, pain-
free ROM.
• DYNAMIC FLEXIBILITY PASSIVE
FLEXIBILITY
• Hypomobility:
• Hypomobility refers to decreased mobility or restricted
motion.
4. • .
• Contracture:
• Restricted motion can range from mild muscle shortening to
irreversible contractures. Contracture is defined as the adaptive
shortening of the muscle-tendon unit and other soft tissues that
cross or surround a joint resulting in significant resistance to passive
or active stretch and limitation of ROM, which may compromise
functional abilities.
• Types of Contracture:
• Myostatic contracture: The musculotendinous unit has adaptively
shortened and there is a significant loss of ROM, there is no specific
muscle pathology present. There may be a reduction in the number
of sarcomere units in series, there is no decrease in individual
sarcomere length. Myostatic contractures can be resolved in a
relatively short time with stretching exercises.
• Pseudomyostatic contracture: Impaired mobility and limited ROM may
also be the result of hypertonicity (i.e., spasticity or rigidity) associated with a
central nervous system lesion, such as a cerebrovascular accident, a spinal cord
injury, or traumatic brain injury. Muscle spasm or guarding and pain may also
cause a pseudomyostatic contracture. If neuromuscular inhibition procedures to
reduce muscle tension temporarily are applied, full, passive elongation of the
apparently shortened muscle is then possible.
5.
6. Types of Contracture:
• Arthrogenic and periarticular contracture: An arthrogenic
contracture is the result of intra-articular pathology. These
changes may include adhesions, synovial proliferation, joint
effusion, irregularities in articular cartilage, or osteophyte
formation. A periarticular contracture develops when connective
tissues that cross or attach to a joint or the joint capsule lose
mobility, thus restricting normal arthrokinematic motion.
• Fibrotic contracture: Fibrous changes in the connective tissue
of muscle and periarticular structures can cause adherence of
these tissues and subsequent development of a fibrotic
contracture.
• Irreversible contracture: Permanent loss of extensibility of soft
tissues that cannot be reversed by nonsurgical intervention may
occur when normal muscle tissue and organized connective
tissue are replaced with a large amount of relatively
nonextensible, fibrotic adhesions and scar tissue or even
heterotopic bone. These changes can occur after long periods of
immobilization of tissues in a shortened position or after tissue
trauma and the subsequent inflammatory response.
7. Selective Stretching
• Selective stretching is a process whereby the overall
function of a patient may be improved by applying
stretching techniques selectively to some muscles and
joints but allowing limitation of motion to develop in other
muscles or joints.
• Overstretching and Hypermobility: Overstretching is a
stretch well beyond the normal length of muscle and ROM
of a joint and the surrounding soft tissues, resulting in
hypermobility (excessive mobility).
8. Interventions to Increase Mobility of
Soft Tissues
• Stretching: Manual or Mechanical/Passive or Assisted: A
sustained or intermittent external, end-range stretch force,
applied with overpressure and by manual contact or a
mechanical device, elongates a shortened muscle-tendon unit
and periarticular connective tissues by moving a restricted joint
just past the available ROM. If the patient is as relaxed as
possible, it is called passive stretching. If the patient assists in
moving the joint through a greater range, it is called assisted
stretching.
• Self-Stretching: Any stretching exercise that is carried out
independently by a patient after instruction and supervision by
a therapist is referred to as self-stretching.
• Muscle energy techniques: These are designed to lengthen
muscle and fascia and to mobilize joints. The procedures
employ voluntary muscle contractions by the patient in a
precisely controlled direction and intensity against a
counterforce applied by the practitioner.
9. Indications and contraindications for
stretching exercise:
• A bony block limits joint
motion.
• There was a recent fracture,
and bony union is
incomplete.
• There is evidence of an
acute inflammatory or
infectious process.
• There is sharp, acute pain
with joint movement or
muscle elongation.
• A hematoma.
• Hypermobility already
exists.
ee
• Limited ROM.
• Muscle weakness and
shortening of opposing
tissue.
• Fitness or sport specific
conditioning program.
• Before or after vigorous
exercise to prevent
muscle soreness.
INDICATIONS
CONTRAINDICTION
S
10. Properties of Soft Tissue: Response to
Immobilization and Stretch
• When soft tissue is stretched, elastic, viscoelastic, or plastic changes
occur. Both contractile and noncontractile tissues have elastic and
plastic qualities; however, only noncontractile connective tissues, not
the contractile elements of muscle, have viscoelastic properties.
• Elasticity is the ability of soft tissue to return to its prestretch resting
length directly after a short-duration stretch force has been removed.
• Viscoelasticity, or viscoelastic deformation, is a time dependent
property of soft tissue that initially resists deformation, such as a
change in length, of the tissue when a stretch force is first applied. If a
stretch force is sustained, viscoelasticity allows a change in the length
of the tissue and then enables the tissue to return gradually to its
prestretch state after the stretch force has been removed.
• Plasticity, or plastic deformation, is the tendency of soft tissue to
assume a new and greater length after the stretch force has been
removed
11. Mechanical Properties of Contractile
Tissue
• Muscle is composed of both contractile and noncontractile
connective tissues. The contractile elements of muscle
give it the characteristics of contractility and irritability.
• The connective tissue structures, which act as a “harness”
of a muscle, are the endomysium, which is the innermost
layer that separates individual muscle fibers and
myofibrils; the perimysium, which encases fiber bundles;
and the epimysium, which is the enveloping fascial sheath
around the entire muscle. It is the connective tissue
framework of muscle that is the primary source of a
muscle’s resistance to passive elongation. When
contractures develop, adhesions in and between collagen
fibers resist and restrict movement.
12. Contractile Elements of Muscle
• Individual muscles are composed of many muscle fibers that
lie in parallel with one another.
• A single muscle fiber is made up of many myofibrils. Each
myofibril is composed of even smaller structures called
sarcomeres, which lie in series (end-to-end) within a myofibril.
• The sarcomere is the contractile unit of the myofibril and is
composed of overlapping myofilaments of actin and myosin
that form cross-bridges.
• The sarcomere gives a muscle its ability to contract and relax.
• When a motor unit stimulates a muscle to contract, the actin-
myosin filaments slide together, and the muscle actively
shortens.
• When a muscle relaxes, the cross-bridges slide apart slightly,
and the muscle returns to its resting length.
13. Mechanical Response of the Contractile Unit
to Stretch and Immobilization
• Response to Stretch:
• When a muscle is stretched and elongates, the stretch force is
transmitted to the muscle fibers via connective tissue
(endomysium and perimysium) in and around the fibers.
• It is hypothesized that molecular interactions link these
noncontractile elements to the contractile unit of muscle, the
sarcomere.
• During passive stretch, both longitudinal and lateral force
transduction occurs. When initial lengthening occurs in the
series elastic (connective tissue) component, tension rises
sharply. After a point, there is mechanical disruption (influence
by neural and biochemical changes) of the crossbridges as the
filaments slide apart, leading to abrupt lengthening of the
sarcomeres, sometimes referred to as sarcomere give. When
the stretch force is released, the individual sarcomeres return
to their resting length
14. Response to Immobilization and
Remobilization
• Morphological changes: If a muscle is immobilized for a
prolonged period of time, the muscle is not used during
functional activities, and consequently, the physical stresses
placed on the muscle are substantially diminished. This results
in decay of contractile protein in the immobilized muscle, as
well as decreases in muscle fiber diameter, the number of
myofibrils, and intramuscular capillary density, the outcome of
which is muscle atrophy and weakness (decreased force
generating capacity of muscle). As the immobilized muscle
atrophies, an increase in fibrous and fatty tissue in muscle also
occurs.
• Immobilization in a shortened position: when a muscle is
immobilized in a shortened position for several weeks, there is
a reduction in the length of the muscle and its fibers and in the
number of sarcomeres in series within myofibrils as the result
of sarcomere absorption.
15. Response to Immobilization and
Remobilization
• Immobilization in a lengthened position: if a muscle is
held in a lengthened position for an extended time period,
it adapts by increasing the number of sarcomeres in
series, sometimes referred to as myofibrillogenesis.
• The adaptation of the contractile units of muscle (an
increase or decrease in the number of sarcomeres) to
prolonged positioning in either lengthened or shortened
positions is transient, lasting only 3 to 5 weeks if the
muscle resumes its pre-immobilization use and degree of
lengthening for functional activities.
16. Neurophysiological Properties
of Contractile Tissue
• The neurophysiological properties of the muscle-tendon unit
also may influence a muscle’s response to stretch and the
effectiveness of stretching interventions to elongate muscle.
Two sensory organs of muscle-tendon units, the muscle
spindle and the Golgi tendon organ, are mechanoreceptors
that convey information to the central nervous system about
what is occurring in a muscle-tendon unit and that affect a
muscle’s response to stretch.
• MUSCLE SPINDLE: The muscle spindle is the major sensory
organ of muscle and is sensitive to quick and sustained (tonic)
stretch. The main function of muscle spindles is to receive and
convey information about changes in the length of a muscle
and the velocity of the length changes.
17. Muscle spindle
• There are two types of intrafusal fiber: Nuclear bag fibers and
nuclear chain fibers, so named because of the arrangement of
their nuclei in the central portions of the fibers. Primary (type Ia
fiber) afferent endings, which arise from nuclear bag fibers,
sense and cause muscle to respond to both quick and
sustained (tonic) stretch. However, secondary (type II) afferents
from the nuclear chain fibers are sensitive only to tonic stretch.
Primary and secondary fibers synapse on the alpha or gamma
motor neurons, which when stimulated cause excitation of their
own extrafusal and intrafusal fibers.
• There are essentially two ways to stimulate these sensory
fibers by means of stretch—one is by overall lengthening of the
muscle; the other is by stimulating contraction of intrafusal
fibers via the gamma efferent neural pathways.
18. Golgi Tendon Organ
• monitor changes in tension of muscle-tendon units.
• These encapsulated nerve endings are woven among
collagen strands of a tendon and transmit sensory
information via Ib fibers. These sensory organs are
sensitive to even slight changes of tension on a muscle-
tendon unit as the result of passive stretch of a muscle or
with active muscle contractions during normal movement.
• When tension develops in a muscle, the GTO fires,
inhibits alpha motor neuron activity, and decreases
tension in the muscle-tendon unit being stretched.
19. Neurophysiological Response of Muscle
to Stretch
• When a stretch force is applied to a muscle-tendon unit either quickly
or over a prolonged period of time, the primary and secondary
afferents of intrafusal muscle fibers sense the length changes and
activate extrafusal muscle fibers via alpha motor neurons in the
spinal cord, thus activating the stretch reflex and increasing
(facilitating) tension in the muscle being stretched.
• The increased tension causes resistance to lengthening and, in turn,
is thought to compromise the effectiveness of the stretching
procedure. When the stretch reflex is activated in a muscle being
lengthened, decreased activity (inhibition) in the muscle on the
opposite side of the joint, referred to as reciprocal inhibition, also
may occur.
• To minimize activation of the stretch reflex and the subsequent
increase in muscle tension and reflexive resistance to muscle
lengthening during stretching procedures, a slowly applied, low-
intensity, prolonged stretch is considered preferable to a quickly
applied, short-duration stretch
20. • The GTO, as it monitors tension in the muscle fibers being
stretched, has an inhibitory impact on the level of muscle
tension in the muscle-tendon unit in which it lies, particularly if
the stretch force is prolonged. This effect is called autogenic
inhibition.
• Inhibition of the contractile components of muscle by the GTO
is thought to contribute to reflexive muscle relaxation during a
stretching maneuver, enabling a muscle to be elongated
against less muscle tension.
• Consequently, if a low-intensity, slow stretch force is applied to
muscle, the stretch reflex is less likely to be activated as the
GTO fires and inhibits tension in the muscle, allowing the
parallel elastic component (the sarcomeres) of the muscle to
remain relaxed and to lengthen.