By, Sean Light CSCS
Proprioceptive Neuromuscular Facilitation, or PNF Stretching, is regarded as the quickest avenue to increased muscle flexibility.
Interestingly, according to Charlie Weingroff DPT, PNF Stretching is not really stretching. Muscle tension comes from your brain and this flexibility technique is designed to tell your brain to stop creating muscular tension at the normal end range of motion, thus creating more flexibility.
PNF can be done with a partner but with a little help, can be done alone as well. I like to use a stretching rope in order to practice this technique on my own.
There are a couple of different PNF techniques. First, we have the Hold-Relax Technique. This process starts with a passive stretch. An example of a passive stretch would be to hook the stretching rope around your foot, like on your back and perform a straight leg raise while keeping the other leg flat on the floor. In the Weingroff video on PNF, he discusses the importance of maintaining pelvic neutrality. It’s important to keep the other leg flat by keeping the knee down, keeping a non-rotated foot and not letting your leg rotate externally. All of these “cheats” will produce excessive slack in your hip, giving you a greater, yet false range of motion in the hamstring. Maintaining pelvic neutrality is easier when done with a partner.
After the passive stretch, the Hold-Relax Technique calls for a few seconds of relaxation followed by an isometric contraction against the passive stretch. This means that, in the case of the hamstring passive stretch explained above, you should be pushing your leg downwards against the force of the rope or partner’s hand. Your force should be equal to the force produced by your partner or rope thus creating no movement also known as an isometric contraction. This is performed for approximately ten seconds.
A second two to three second relax ensues which is then followed by a final passive stretch. This final passive stretch takes advantage of the new, increased range of motion that was just developed in the stretched muscle. Ten seconds is also recommended for this passive stretch.
Make sure you give yourself a minimum of twenty seconds of recovery before performing PNF on the same muscle group. However, according to an HFLTA study, performing multiple rounds of PNF on one group is no more effective than one round.
A second PNF technique is the Hold-Relax-Contract Technique. This starts like the aforementioned technique with a passive stretch followed by an isometric contraction. This time, the Hold-Relax-Contract technique calls for an antagonist contraction and held for about ten seconds. This is made easier by reciprocal inhibition. Reciprocal inhibition is when an antagonist contracts, the agonist is generally forced to relax.
To understand the meaning of an antagonist we must first define an agonist. An agonist is the primary mover in an action. In a bicep curl, the agonist is the bicep and in a triceps pull down the agonist is the triceps. The antagonists however are the muscles that provide resistance to the movement. So in the same examples, the triceps antagonize the bicep curl and the biceps do the same to a triceps pull down.
The final point to the Hold-Relax-Contract Technique is that it does not have a final passive stretch. Because of this, this PNF strategy is among the safer strategies.