Fiber Content: Complex stretching

Welcome to the 21st century. The past 50 years have seen remarkable innovations in technology, medicine, and even physical fitness training. People are starting to understand the health benefits of proper daily physical activity. This could be due to the increase in lifestyle-related illness and pathologies. The latest data released by the Centers for Disease Control in 2008 showed that every state but Colorado had a 20 percent or higher obesity rate. However, it’s easier than one might think to achieve a healthy lifestyle through physical activity.

The previous installment of “Fiber Content” emphasized static stretching — specifically, the increased health and performance that results. This article will focus on slightly more complex methods of stretching. Proprioceptive neuromuscular facilitation (PNF) stretching has been a staple for high-level athletes for the past 30 years and has finally trickled down to the general fitness enthusiast.

Many experts consider PNF superior to other forms of stretching because it facilitates muscular inhibition. One of the main drawbacks to static stretching is the possibility of stretching an overactive muscle. When performing static stretching, opposing muscles (agonist and antagonist) may sometimes co-contract, not allowing for full relaxation of the muscle being stretched and yielding a less than optimal result. If done correctly, PNF stretching eliminates this possibility.

During PNF stretching, three specific muscle actions are used to create the relaxed state and passive stretch. Concentric — active shortening of the muscle — and isometric actions — preventing the muscle from changing length — are performed on the antagonist muscle (the muscle being stretched) followed by a concentric contraction of the agonist (the muscle being trained, opposite the antagonist) to cause reciprocal inhibition.

Reciprocal inhibition is the body’s ability to allow one muscle group to relax so the other can contract fluidly. If this did not happen during normal movement, both the agonist and antagonist would contract simultaneously, causing jerky, almost robot-like movements. During the stretching, the terms contract and hold are used to describe the concentric and isometric contractions, respectively. During the contraction of the agonist muscle, there is a passive static stretch applied, referred to as relax.

There are three basic techniques of PNF stretching used: hold-relax, contract-relax, and hold-relax with agonist contraction. In performing all these exercises on the hamstring, for example, a long piece of sturdy rope or a lengthy belt will be needed. In all three examples, the rope or belt will be looped around the arch of the foot of the leg being stretched, and the person should be lying on the ground with enough rope or belt remaining to hold on to during the stretch. It is imperative during the stretch that the leg remains as straight as possible to ensure proper stretching of the full muscle. Each stretch has a starting position when the belt is used to apply just enough pressure that there is mild discomfort, and this position is held for 10 seconds — this static stretch allows the muscle to be relaxed.

Hold-Relax: Begin with the aforementioned starting position. While maintaining a stretch, begin to pull slowly on the rope to cause an increase in tension while trying to hold the position of the leg, causing an isometric contraction of the antagonist (hamstring) muscle for six seconds. Lastly, relax and statically stretch the hamstring muscle group for 30 seconds, increasing the range of motion of the leg.

Contract-Relax: Begin once again with the starting stretch. While maintaining tension in the band, concentrically extend the leg down to the ground or through a full range of motion. Relax and passively bring the leg up to an increased range of motion by pulling on the belt and holding the hamstring in a relaxed and statically stretched state for 30 seconds.

Hold-Relax with Agonist Contraction: This technique is identical to the hold-relax method mentioned above in the first two phases (relaxed and contract). Following the isometric contraction of the hamstring muscles group, contract the quadriceps and hip flexor muscle groups by bringing the thigh closer to the body. Simultaneously pull on the belt to increase the active range of motion.

With all three techniques, each subsequent relaxed static stretch should be at an increased range of motion. These techniques can be repeated anywhere from 2–3 times on each limb. Perform only one of the three stretches per session and try to vary the techniques weekly to stay interested.

Like static stretching, these stretches can be performed before, during, and after training sessions to promote increased flexibility, increased strength performance, and increased recovery time.

For pictures and further inquiries regarding both static and PNF stretching, the Internet is a great place to start. If you have questions or comments, please e-mail me (schultzk@).