What is PNF Stretching?

Before we really get into proprioceptive muscular facilitation (PNF) stretching, you should take a minute to learn more about the basics of flexibility training.

PNF stretching is probably the most effective form of flexibility training available to you for increasing your range of motion (ROM). This is a more advanced form of flexibility training, involving both the stretch and contraction of the targeted muscle group.

Two Girls Using PNF Stretching
Two Girls Using PNF Stretching

There is lots to learn about PNF stretching, so now we will examine why PNF stretching is your best choice for static flexibility training, as well as who, when, where, and how to use it.

Benefits of PNF stretching:

  • targeting a specific muscle group
  • increasing flexibility and ROM
  • increasing muscular strength
  • physical therapy
  • rehabilitation
  • improve recovery time after a strenuous workout

Caution!

Precautions should be taken when using PNF stretching, since PNF can increase the risk of soft tissue injury by putting added stress on the targeted muscle group. To help reduce this risk, it is your responsibility to warm up target muscle groups before starting a PNF stretching session.

Warming up prior to stretching will provide a number of benefits, but we are mostly concerned with priming the body and mind for more strenuous activity. Our main goal is to increase the body’s core and muscle temperatures. This is essential to gain the maximum benefit from flexibility training.

You should not attempt to use PNF stretching with a recently injured muscle, but you should attempt to use PNF stretching when engaging in rehabilitation after your injury has at least somewhat healed. PNF stretching was originally developed as a very effective form of rehabilitation.

PNF Stretching

To begin, the target muscle group is positioned so that the muscles are under tension and stretched. You then contract the stretched muscle group for about 6 seconds while your partner, or an immovable object, applies resistance sufficient for resisting movement.

Finally the contracted muscle group is relaxed and your partner applies a controlled stretch for about 30 seconds. Allow the target muscle group 30 seconds to recover and repeat the process at least twice. Four detailed techniques for PNF stretching are described below.

There are two types of PNF stretching:

  1. passive – stretching without a muscular contraction
  2. active – using a voluntary muscular contraction

How PNF Stretching Works

For the following information, you should know that the golgi tendon organ relaxes a muscle after a sustained contraction has been applied to it for longer than 6 seconds.

Isometric contractions (the hold phase) and concentric contractions (the contract phase) used immediately before the passive stretch (the relax phase) facilitate autogenic inhibition.

Autogenic inhibition is a reflex relaxation that occurs in the same muscle where the golgi tendon organ is stimulated.

Similarly, we can use a technique that involves a concentric contraction of the muscle group opposing that which is being stretched, in order to achieve reciprocal inhibition.

Reciprocal inhibition is a reflex muscular relaxation that occurs in the muscle that is opposite the muscle where the golgi tendon organ is stimulated.

Using the hold, contract, and relax phases, we can develop the following 4 PNF stretching techniques. While slightly different, each technique starts by holding a passive stretch for about 10 seconds.

PNF Stretching Techniques

  1. Hold-Relax

    Your stretching partner will have you passively stretch the target muscle for about 10 seconds against his or her hand. This stretch should elicit a sense of mild discomfort.

    Next, you will apply an isometric contraction by pushing the target muscle against your partner’s hand. Your partner should apply just enough resistance to keep the target muscle in place. This ‘hold’ phase lasts for 20 seconds.

    Finally, you will relax as your partner eases you into a static stretch for 30 seconds. This second static stretch should move further than the initial static stretch thanks to our buddy Autogenic Inhibition.

  2. Contract-Relax

    Your stretching partner will have you passively stretch the target muscle for about 10 seconds against his or her hand. This stretch should elicit a sense of mild discomfort.

    Next, you will apply an isometric contraction by pushing the target muscle against your partner’s hand. Your partner should apply just enough resistance to allow the target muscle to move through its full range of motion (ROM). This ‘contract’ phase lasts for 20 seconds.

    Finally, you will relax as your partner eases you into a static stretch for 30 seconds. This second static stretch should move further than the initial static stretch due to Autogenic Inhibition.

  3. Contract-Relax with Antagonist Contraction

    Your stretching partner will have you passively stretch the target muscle for about 10 seconds against his or her hand. This stretch should elicit a sense of mild discomfort.

    Next, you will apply an isometric contraction by pushing the target muscle against your partner’s hand. Your partner should apply just enough resistance to keep the target muscle in place. This ‘hold’ phase lasts for 10 seconds.

    Next, you will concentrically contract the antagonist, or opposite, muscle to increase the stretch by attempting to pull the target muscle in the same direction as the stretch. Your partner should lightly assist you in continuing the stretch, but the focus should be on antagonistic contraction. This ‘contract’ phase lasts for 10 seconds.

    Finally, you will relax as your partner eases you into a static stretch for 30 seconds. This second static stretch should move further than the initial static stretch due to Reciprocal Inhibition.

  4. Dynamic/Ballistic Hold-Relax

    Similar to Hold-Relax and Contract-Relax with Antagonist Contraction, also called Hold-Relax-Swing or Hold-Relax-Bounce. (Wikipedia)

    Your stretching partner will have you passively stretch the target muscle for about 10 seconds against his or her hand. This stretch should elicit a sense of mild discomfort.

    Next, you will apply an isometric contraction by pushing the target muscle against your partner’s hand. Your partner should apply just enough resistance to keep the target muscle in place. This ‘hold’ phase lasts for 10 seconds.

    Next, you will contract the target muscle groups using ballistic or dynamic stretching to increase the ROM of the target muscle. This ‘contract’ phase lasts for 30 seconds.

    This type of stretching is very risky. It should be used only by athletes who have achieved a high level of control over their body’s stretch reflex reactions.

General Guidelines for PNF Stretching

  • Always precede PNF stretching with 10-15 minutes of moderate exercise.
  • Avoid PNF prior to exercise. Choose dynamic stretching and mobility work instead.
  • Perform only one stretch per muscle group per PNF session.
  • Perform at least two sets of each stretch for the chose muscle group.
  • Hold each stretch for 30 seconds after the initial contraction.
  • Separate PNF stretching routines with at least a 48 hour recovery period.

Who Should Use PNF Stretching

No matter what type of PNF stretching you choose, you will benefit from a wonderful flexibility tool: increased muscular inhibition. Because PNF stretching encourages muscular inhibition, it is considered superior to all other forms of flexibility training.

PNF stretching should be used by all athletes as a supplement to a vigorous exercise program. It should be performed after exercise on training days, and/or following a 10-15 minute moderate warm up on non-training days.

PNF stretching should also be used as part of a physical therapy program. PNF is great for recovering from injury. It can also be used for people with degenerative diseases such as MS and Parkinson’s Disease to increase muscular strength and flexibility, and to encourage stability of the trunk, hip, and shoulder girdle.

Example of PNF Stretching

For this example I will only show an example of the Hold-Relax PNF stretch, as it is the easiest and quickest to learn.

PNF Stretching - Passive Stretch
PNF Stretching – Initial Passive Static Stretch
PNF Stretching - Contraction
PNF Stretching – Isometric Contraction
PNF Stretching - Passive Stretch
PNF Stretching – Final Passive Static Stretch

Images courtesy of The Stretching Handbook

Resources:

Appleton, B. Stretching and Flexibility.

Holt, L.E. Comparative study of three stretching techniques. Perceptual and Motor Skills. 31:611-16. 1970

Tanigawa, M.C. Comparison of the hold relax procedure and passive mobilization on increasing muscle length. Physical Therapy. 52:725-35. 1972

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7 Responses to “What is PNF Stretching?”

    • Healthandfitnessgeek: No, you are wrong. It is always best to WARM UP before doing any workouts to avoid injuries. It is always best to stretch AFTER workouts to stay healthy. Thanks for your spam comment.

    • I wouldn’t even have taken an attitude with you if your attempted spam comment made any sense. As a blog comment moderator it gets aggravating when people post nonsensical comments just for the sake of getting a backlink. If you bothered to read the article you wouldn’t be posting things like “It is always best to do stretching before doing any workouts,” when it is obvious that you should not stretch before workouts unless you are using dynamic stretches, which you didn’t mention. That’s my story and I’m sticking to it.

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