Looking for a foolproof, surefire way to increase recovery, reduce injury and therefore increase muscular gains? Who wouldn’t? Surely these are things everyone wants. But the way to do this is neglected by the vast majority of gym goers (sometimes myself included). What I am talking about is stretching – today in particular I am going to discuss PNF stretching.
What is PNF Stretching?
PNF stands for proprioceptive neuromuscular facilitation. In the mid 1900s a neurophysiologist Herman Kabat developed the PNF stretching using natural movement patterns. It was based of the work of Charles Sherrington who created a model of neuromuscular facilitation and inhibition. Kabat knew of the myotatic 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. This led to the theory that combinations of movement would be far more optimal than the more outdated moving of a single joint at a time. PNF stretching was originally done on polio patients to help them regain lost range of motion. Kabat then received help from Margaret Knott and Dorothy Voss who both helped show Kabat PNF would work to help anyone increase range of motion and improve flexibility.
So what exactly is PNF stretching? It’s a passive stretch or maybe a better term is a facilitated stretch therefore a partner is required to do this. On the face of it PNF stretching is very simple.
Stretch. Isometrically contract the muscle. Then stretch again.
How long should I hold a PNF stretch for?
The isometric contraction should be done for at least 20 seconds for maximal results. This in turn fatigues fast twitch muscle fibers that are much less likely to tighten up during stretching. So on the face of it PNF is super simple and super effective, which is exactly why I like it so much.
PNF Stretching Techniques
Since its birth there has been many PNF techniques developed but in my opinion there are two main methods that are best for increased range of motion, injury prevention, improved flexibility and better recovery.
- Contract Relax aka contract-relax-contract or contract-relax-agonist-contract.
The partner/helper moves the limb to the limit of its range of motion, following this the patient then pushes against the partner’s resistance (for 20 seconds). After the resistance the patient then contracts the agonist muscle (the opposite of the muscle the patient was contracting to push against the partner’s resistance) and moves their own limb through the enlarged range of motion.
This is an example of active stretching, since increasing the range of motion is done by the patient. This is also safer than the hold-relax method below, since you are in complete control of your body and how far you move.
After contract-relax, the patient is instructed to move their limb throughout the entire range of motion of the joint, so that they can move through the new range of motion without the partner’s help.
- Hold-Relax. This is typically done when the range of motion for a muscle is particularly small, or the body cannot flex that way because of weakness and/or pain.
First, the partner/helper stretches the patient to the limit of their normal range of motion. The patient then resists the partner as they move the body part through a increased range of motion – this is the 20 second muscle contraction. This is followed by the patient then relaxing and allowing their body part to be moved into the new, increased mange of motion by the partner.
This, unlike Contract-Relax, is a version of a passive stretch, this is because the actual stretching is done by the helper. The partner will gradually move your limb through an larger range of motion. Performing Hold-Relax PNF stretching is actually more dangerous than Contract-Relax stretching since the partner assisting you might stretch your muscle too far accidentally. Therefore feedback between the patient and partner is of primary importance during Hold-Relax so no harm is done to the “stretchee”.
The Most Common PNF Stretch
The most common PNF stretch you will see performed is on the hamstring, with the patient lying flat on their back with their stretched leg in the air as far up as possible until the patient feels a stretch in the hamstring. The partner will place the patients leg just below the shoe on their shoulder and initiate movement from there.
PNF stretching can be performed on any muscle group with the help of a partner, so if you are looking for a way to increase range of motion through a muscle, improve recovery and reduce injury risk try PNF.