PNF( Proprioceptive  Neuromuscular Facilitation ):

PNF Stretching is an occupational therapy and physical

therapy procedure designed in the 1940s and 1950s to

rehabilitate patients with paralysis. It is often a combination

of passive stretching and isometrics contractions. In the

1980s, components of PNF began to be used by sport

therapists on healthy athletes. The most common PNF leg or

arm positions encourage flexibility and coordination

throughout the limb's entire range of motion.

PNF is used to supplement daily stretching and is

employed to make quick gains in range of motion to help

athletes improve performance. Good range of motion makes

better biomechanics, reduces fatigue and helps prevent

overuse injuries. PNF is practiced by chiropractors, physical

therapists, occupational therapists, massage therapists,

athletic trainers and others.

PNF stretching is one of the most effective forms of

flexibility training for increasing range of motion.PNF

techniques can be both passive (no associated muscular

contraction) or active (voluntary muscle contraction). While

there are several variations of PNF stretching, they all have

one thing in common - they facilitate muscular inhibition. It is

believed that this is why PNF is superior to other forms of

flexibility training.

Both isometric and concentric muscle actions completed

immediately before the passive stretch help to achieve

autogenic inhibition - a reflex relaxation that occurs in the

same muscle where the golgi tendon organ is stimulated.

Often the isometric contraction is referred to as 'hold' and the

concentric muscle contraction is referred to as 'contract'.

A similar technique involves concentrically contracting

the opposing muscle group to that being stretched in order to

achieve reciprocal inhibition - a reflex muscular relaxation

that occurs in the muscle that is opposite the muscle where

the golgi tendon organ is stimulated.

History:

In the early to mid 1900s physiologist Charles

Sherrington  popularized a model for how the neuromuscular

system operates. Radiation  is when maximal contraction of a

muscle recruits the help of additional muscle flexibility. Based

on that, Herman Kabat, a neurophysiologist, began in 1946 to

look for natural patterns of movement for rehabilitating the

muscles of polio patients. He knew of the myostatic stretch

reflex which causes a muscle to contract when lengthened

too quickly, and of the inverse stretch reflex, which causes a

muscle to relax when its tendon is pulled with too much force.

He believed combinations of movement would be better than

the traditional moving of one joint at a time. To find specific

techniques, he started an institute in Washington, DC and by

1951 had two offices in California as well. His assistants

Margaret Knott and Dorothy Voss in California applied PNF to

all types of therapeutic exercise and began presenting the

techniques in workshops in 1952.

During the 1960s, the physical therapy departments of

several universities began offering courses in PNF and by the

late 1970s PNF stretching began to be used by athletes and

other healthy people for more flexibility and range of motion.

Terms about muscle contraction are commonly used when

discussing PNF.

Concentric isotonic contraction is when the muscle

shortens, eccentric isotonic is when it lengthens even though

resisting a force, and isometricis when it remains the same

length.

Indications of   PNF :   -

1. Loss of range of motion.

2. Acute and chronic pain.

3. Muscle tightness.

4. Muscle cramp.

5. Loss of flexibility.

Contra-indications : -

1. Post-operative : PNF Stretching is not done after recent post

operation because the repairs that were made during surgery can be

counteracted like muscle or tendons pulling away from reattachment

due to tension stretching implements. Tissue healing must be

determined from intense stretching can be performed.

2.   Instability   of joints :  If  a person has an unstable joint in the area

where stretching is applied, he/she may not be able to control the

movement of the stretch and hyper mobility may cause injury.

3. Under age 18 years : PNF stretching is not recommended for

anyone below the age of 18 years as intense stretching may disrupt

the growth plates and may cause disease like Osgood Schlatter’s

disease.

4. Already stretched muscles : PNF is not performed more than once

a day due to stress it produces on muscles and tendons.

The Fundamentals of   PNF : -

PNF may be categorised in terms of five P-factors: Principles,

Procedures, Patterns, Positions and Postures, with joint Pivots and

Pacing (Timing) as important sub-categories. The methods comprising

these factors were formulated from findings on neuromuscular

development, such as the functional evolution of all movement from

motor immaturity to motor maturity in the growing child or novice

athlete in definite sequences progressing logically from:

* total to individuated

* proximal to distal, distal to proximal

* mobile to stabile

* gross to selective

* reflexive to deliberate

* overlapping to integrative

* incoordinate to coordinate

The Principles of PNF : -

The basic principles of PNF may be summarised as follows:

1. Use of spiral and diagonal movement patterns

2. Motion crossing the sagittal midline of the body

3. Recruitment of all movement components (e.g. flexion-extension)

4. Exercising of related muscle groups

5. Judicious eliciting of reflexes

6. Movement free of pain, but not free of effort

7. Comfortable full-range movement

8. Application of maximal resistance throughout the range of non-ballistic movement

9. Use of maximal resistance to promote overflow (irradiation) of muscle activity

10. Use of multiple joint and muscle action

11. Commencement of motion in the strongest range

12. Use of static and dynamic conditions

13. Appropriate positioning of joints to optimise conditioning

14. Exercising of agonists and antagonists

15. Repeated contractions to facilitate motor learning, conditioning and adaptation

16. Selection of appropriate sensory cues to facilitate action

17. Emphasis on visuo-motor and audio-motor coordination

18. Use of distal to proximal sequences in neuromuscularly mature subjects

19. Use of stronger muscles to augment the weaker

20. Progression from primitive to complex actions

21. Planning of each phase to lay foundations for the next phase

22. All activities are integrated and goal directed

23. Use of adjunct techniques (e.g. massage, vibration).

Procedure for PNF : -

Pattern of Motion : Normal motor activity occurs in

synergistic and functional patterns of movement. PNF

patterns are “spiral and diagonal” in character and combine

motion in all three planes flexion/extension,

abduction/adduction and transverse rotation.

Neck Patterns : -

1. Neck flexion with rotation to the right.

2. Neck extension with rotation to the left

Upper Extremity : -

Diagonal 1 : – Shoulder Flexion, Adduction, External Rotation

(D1 Flexion) and Extension, Abduction, Internal Rotation (D1

Extension); Elbow flexed/extended; Wrist & Fingers

Extension to flexion.

Diagonal 2 : –  Shoulder Flexion, Abduction, Lateral Rotation

(D2 Flexion) and Extension, Adduction and Medial Rotation

(D2 Extension); Elbow Extended; Wrist & Fingers Flexion to

Extension.

Trunk : -

Upper trunk in sitting position : Flexion with rotation to the left

(Chopping), Extension with rotation to  the right (Lifting).

Lower Trunk in supine position : Flexion with rotation to the

left, Extension with rotation with the right.

Lower Extremity : -

Diagonal 1 : Hip Flexion, Adduction, External Rotation; Knee

extended; Foot Dorsi Flexion (D1 Flexion) and Hip Extension,

Abduction, Internal Rotation; Knee Extension; Foot Planter

Flexion (D2 Extension).

Diagonal 2 : Hip Flexion, Abduction, External Rotation; Knee

Extension; Foot Planter Flexion (D2 Flexion) and Hip

Extension, Adduction, Interna Rotation; Knee Extension; Foot

Dorsi Flexion (D2 Extension).

Timing: In PNF patterns normal timing is from distal to

proximal. Distal segments (hand/wrist or foot/ankle) move

first followed closely by more proximal components. Rotation

occurs throughout the pattern, from beginning to end.

Timing for Emphasis : Maximum resistance is used to elicit a

strong contraction and allow overflow to occur from strong to

weak components within a synergistic pattern; the strong

muscles are resisted isometrically while motion is allowed in

the weaker muscles.

Resistance : Resistance facilitates muscle contraction and

motor control. Resistance is applied manually and

functionally through the use of gravity to all types of

contractions.

Overflow or Irradiation : Refers to spread of muscle response

from stronger muscles in a synergistic pattern to weaker

muscles; maximal resistance is the main mechanism for

securing overflow or irradiation. Enhance synergistic actions

of muscles, increase strength.

Manual Contacts : Precise manual contacts (grip) are used to

provide pressure to tactile and pressure receptors overlying

the muscles to facilitate contraction and guide direction of

movements; pressure is applied opposite to the direction of

the desired motion.

Positioning : Muscle positioning at optimal range of function

allows for optimal responses of muscles. The greatest muscle

tension is generated in mid-ranges with weak contractile

force occuring in the shortened ranges.

Therapist Position and Body Mechanics : Therapist is

positioned directly in line with the desired motion in order to

optimize the direction of resistance that is applied.

Verbal Commands : Verbal commands allow for the use of

well-timed words and appropriate vocal volume to direct the

patient’s movement.

Vision : Vision is used to guide the patient’s movements,

enhance muscle contraction, and synergistic patterns of

movement.

Stretch : The elongated position/lengthened range and the

stretch reflex are used to facilitate muscle contraction. All

muscles in the pattern are elongated to optimize the effects of

stretch. Commands for voluntary movement are always

synchronized with the stretch to enhance the response.

Approximation : Approximation is used to facilitate

extensor/stabilizing muscle contraction and stability; can be

applied manually, functionally through the use of gravity

acting on body during upright positions, or mechanically using

weights or belts.

Traction : A distraction force is used to facilitate muscle

contraction and motion, especially is applied in flexion

patterns or pulling motions; force is applied manually during

PNF. Gentle distraction force is also useful in reducing joint

pain.

PNF Techniques : –

Reversal of Antagonists : A group of techniques that allow

for agonist contraction followed by antagonist contraction

without pause or relaxation.

* Dynamic Reversals (Slow Reversals) : Utilizes isotonic

contractions of first agonists, then antagonists performed

against resistance. Contraction of stronger pattern is selected

first with progression to the weaker pattern. The limb is

moved through full ROM.

* Stabilizing Reversals : Utilizes alternating isotonic

contractions of first agonists, then antagonists against

resistance, allowing very limited ROM.

* Rhythmic Stabilization : Utilizes alternating isotonic

contractions of first agonists, then antagonists against

resistance, no motion is allowed.

Repeated Contractions : Repeated isotonic contractions

from the lengthened range, induced by quick stretches and

enhanced by resistance; performed through the range or part

of range at a point of weakness. Technique is repeated

during one pattern or until contraction weakens.

Combination of Isotonics : Resisted concentric contraction

of agonist muscles moving through the range is followed by a

stabilizing contraction and then eccentric contraction, moving

slowig back to the start position; there is no relaxation

between the types of contractions. Typically used in anti

gravity activities/assumption of postures.

Rhythmic Initiation : Voluntary relaxation followed by

passive progressing to active-assisted and active-resisted

movements to finally active movements. Verbal commands

are used to set the speed and rhythm of the movements.

Light tracking resistance is used during the resistive phase to

facilitate movement.

Contract-Relax : a relaxation technique usually performed at

a point of limited ROM in the agonist pattern. Strong, small

range isotonic contraction of the restricting muscles

(antagonist) with emphasis on the rotators is followed by an

isometric hold. The contraction is held for few seconds and is

then followed by voluntary relaxation and movement into the

new range of the agonist pattern. Movement can be passive

but active contraction is preferred.

Hold-relax : A relaxation technique usually performed in a

position of comfort and below a level that causes pain. Strong

isometric contraction of the restricting muscles (antagonists)

is resisted, followed by voluntary relaxation, and passive

movement into the newly gained range of the agonist pattern.

Replication (Hold-Relax Active motion) : The patient is

positioned in the shortened/end position of a movement and

is asked to hold. The isometric contraction is resisted

followed by voluntary relaxation and passive movement into

the lengthened range. The patient is then instructed to move

back into the end position; stretch and resistance are applied

to facilitate the isotonic contraction. For each repetition,

increasing ROM is desired.

Resisted Progression : Stretch, approximation and tracking

resistance is applied manually to facilitate pelvic motion and

progression during locomotion; the patient’s momentum,

coordination and velocity. It can be applied using elastic band

resistance

Rhythmic Rotation : Relaxation is achieved with slow,

repeated rotation of a limb at a point where limitation is

noticed. as muscles relax the limb is slowly and gently moved

into the range, As a new tension is felt, it is repeated. The

patient can use active movements for rhythmic rotation or the

therapist can perform it passively. Voluntary relaxation when

possible is important.

General guidelines when completing PNF stretching:

1. Leave 48 hours between PNF stretching routines.

2. Perform only one exercise per muscle group in a session.

3. For each muscle group complete 2-5 sets of the chosen

exercise.

4. Each set should consist of one stretch held for up to 30

seconds after the contracting phase.

5. PNF stretching is not recommended for anyone under the

age of 18.

6. If PNF stretching is to be performed as a separate

exercise session, a thorough warm up consisting of 5-10

minutes of light aerobic exercise and some dynamic

stretches must precede it.

7. Avoid PNF immediately before, or on the morning of

competition.

Gallery:

Arm-front diagonal flexion.

 

Leg-front diagonal flexion.

PNF patterns (diagonal), lower extremities

Front cross

 

Out back

 

Back cross

 

Out front

PNF patterns (diagonal), upper extremities

Cross low

 

Back high

 

Cross high

 

Back low