Trigger points are taut fibers within the muscle fiber. The sarcomere, or contractile unit of the muscle fiber, becomes shortened due to trauma, injury, overload of a muscle or muscle groups, nutritional deficiencies, poor posture and sleeping positions among other perpetuating factors.
Most massage therapists I have taught, thought that trigger points cause only referred pain; however, more recently trigger points have been shown to cause loss of range of motion. They also can cause pain or such other types of sensations as tingling, heaviness or numbness; and a decrease in strength or in endurance.
The Biochemical Feedback Loop
The myofascial dysfunction that comes with the shortened muscle fibers causes postural distortions that further complicate a person’s ability to live and work without pain. As the tight fibers keep the muscle shortened and increase pain, it becomes a biochemical feedback loop that can lead the person to develop myofascial pain syndrome.
You might ask: “My client’s muscles are in the painful feedback loop. How do I stop it?”
As painful muscles (harboring trigger points) stay in the shortened position, there is a chemically mediated crisis brewing within the trigger point complex. Painful muscles:
1. Beget tight muscles;
2. Prevent us from moving; and
3. Create more pain.
Myofascial trigger point therapy is now to the rescue! A properly trained massage therapist can incorporate the 7-Step Trigger Point Protocol, and Proprioceptive Neuromuscular Facilitation (PNF) is one of the most valuable parts of this protocol. You’ve probably tried static stretching, yoga class and foam rolling. That’s not enough. PNF is the best way to stop the feedback loop of pain-tightness-pain and restore contracted muscle segments to normal resting length.
What is PNF?
Let’s look at the concept of length-tension relationship and the sarcomere. The premise of the length-tension relationship is the amount of tension produced by a sarcomere or group of sarcomeres is based on its length.
A shortened sarcomere, (or tens of thousands of muscle cells with contracted sarcomeres) can be found within the active trigger point complex. This contracted muscle bundle will produce less force and not perform to its full potential, because an already-shortened muscle cannot fully contract to create force or work that is needed. The same thing applies to an overstretched sarcomere. There is no room for a stretch for pre-load, so again, less power or endurance is the result.
Let’s take a closer look at the length-tension relationship and how it affects overall muscle performance and force production.
Think back to anatomy and physiology class and the sliding filament theory. The actin and myosin filaments cross each other to produce a muscular contraction. The “Z” lines are the outside border of a sarcomere. In a shortened sarcomere, the distance between the Z lines is shorter compared to a normal sarcomere.
A shortened sarcomere will not produce maximal force. This is where myofascial trigger point therapy and PNF techniques can be used to restore the normal resting length to these shortened or contracted areas.
The Physiology of PNF Techniques
PNF is based on the foundation of moving the body part into a point of resistance in the range of motion in which it works.
This movement incorporates both passive and active muscle actions facilitating muscular inhibition of the antagonist (this is autogenic inhibition). Also, this technique, by using an active client-initiated muscle contraction, allows the client to be aware of the force produced so they in turn can be aware of the tension within their habitual feedback loop.
PNF is a great addition to a massage or myofascial trigger point therapy treatment to help normalize and optimize tissue length and tension, restore resting length, eliminate pain, and break neuromuscular holding patterns.
PNF stretching starts with a pre-stretch lasting 10 seconds. The next steps vary based on the PNF technique being utilized. The final step is a stretch held for 30 seconds.
PNF stretching can be incorporated into the treatment session or it can be taught to your clients to do at home as part of a self-care program. There are several different PNF techniques to incorporate into your treatment session. These include contract-relax, hold-relax, and hold-relax with agonist contraction.
The Hold-Relax Technique: For this technique, I made a video which shows how to stretch the hamstrings using the hold-relax PNF technique. This is a great way to get your client engaged in the session and to re-train their muscles. This video demonstrates the hold-relax technique for the hamstrings.
Hold-Relax Technique and Reciprocal Inhibition Stretching: For this technique, I made a video which shows how to stretch the quadriceps using the hold-relax technique and reciprocal inhibition technique. This video demonstrates these techniques.
What is Proprioception?
Let’s talk about proprioception. Proprioception is simply where your body is in space. Proprioceptors are a type of receptor cell that are sensitive to stimuli with respect to the position of the joint and muscles. There are two types of mechanoreceptors that are worthy of discussion, muscle spindles and golgi tendon organs.
Muscle spindles are located in the intrafusal fiber of the muscle and monitor the stretch of a muscle and its rate of change in length. So when the muscle is lengthened so are the intrafusal fibers. The central nervous system gets involved when a muscle is stretched or lengthened too far and sends a stimulus for the muscle to contract.
Golgi tendon organs are located in the musculotendinous junction. Their role is to help the body respond to changes in the tension of a muscle. GTO’s monitor the pulling force on the tendon and if too much force or tension is detected, the muscle will relax due to inhibitory signals sent from the nervous system.
If you work with trigger points, consider adding PNF to your session in order to improve the outcome of myofascial trigger point therapy.
About the Author:
Julie Zuleger, PhD, has over 20 years of experience as a licensed massage therapist, board certified myofascial trigger point therapist, athletic trainer and human movement specialist. She teaches continuing education courses for massage therapists, athletic trainers, fitness, and wellness professionals. Zuleger is the owner of Impact Nutrition and Wellness Coaching LLC. For more information about her online courses visit Chicago Trigger Point Seminars.