Facilitated range of motion is a type of stretch that combines passive stretching and isometric contractions of the muscle. It is also called proprioceptive neuromuscular facilitation stretching. Athletes use PNF stretching in their training to help increase range of motion, and it is also used by physical therapists in the rehabilitation of muscles.
History
Facilitated active range of motion stretching was developed in the mid-1900s by a neurophysiologist, Herman Kabat, and his two physical therapist assistants, Margaret Knott and Dorothy Voss. Kabat expanded on Sir Charles Sherrington's previous research on the operation of the neuromuscular system and developed a way to use PNF as rehabilitation for paralyzed polio patients. From 1946 to 1951, Kabat and Knott developed nine ways to rehabilitate the muscles through PNF and started researching ways it could be used with exercise. In 1952, Knott and Voss started teaching PNF to those willing to learn. It has been rising in popularity since then. Today, it is commonly used by athletes to increase range of motion.
Types
Facilitated stretching has two major types: hold-relax and contract-relax. The hold-relax stretch is used when a lack of range of motion exists because of weakness or pain. The athlete actively moves his limb into his complete range of motion and holds it there. As the therapist tries to move the limb into a greater range of motion, the athlete resists by isometrically contracting his muscles. The athlete relaxes his muscles before moving his limb back into the new range of motion to repeat the exercise. The contract-relax stretch is used when the athlete has a limited range of motion. The therapist moves the athlete's limb past the range of motion. The athlete isometrically contracts his muscles, trying to push his limb into a smaller range of motion while the therapist resists the movement. The athlete relaxes his muscles before repeating the exercise.
Effects
Facilitated range of motion stretching improves range of motion and flexibility to a greater extent than other stretching techniques. Because this type of stretching uses isometric contractions, it keeps your neuromuscular system engaged. While your muscles are contracting, the tension-sensing mechanoreceptors are engaged, resulting in a reduced excitement of the contracting muscle and an increased stretch. An increased range of motion can be seen within one repetition of the stretch.
Time Frame
A single repetition of a facilitated stretch can increase your range of motion by three to nine degrees. This is seen immediately after the stretch. Further repetitions show only minor changes. The new range of motion should last from six minutes to seven days, depending on how many repetitions and how often you perform the stretches. Once the stretching has stopped, range of motion will begin to decrease. You should perform these stretches two to three times per week to maintain your new range of motion.
Considerations
Whenever partner stretches are performed, safety is an issue. Make sure your partner is not using too much force while resisting your contractions. You should only contract your muscles at 20 percent of your maximum contraction, otherwise an overuse injury could occur. Your partner should also be gentle when positioning your limb past its range of motion. If done too forcefully or positioned too far, you have an increased chance of injury.
References
- "Sports Medicine"; Proprioceptive Neuromuscular Facilitation Stretching: Mechanisms and Clinical Implications; Melanie Sharman, Andrew Cresswall, and Stephen Riek; 2006
- "Facilitated Stretching"; Robert McAtee and Jeff Charland; 2007
