Throughout this document, when the term static stretching or passive stretching is used, its intended meaning is the definition of passive stretching as described in the previous section. You should be aware of these alternative meanings, however, when looking at other references on stretching. Isometric Stretching PNF Stretching : next section Static Stretching : previous section Types of Stretching : beginning of chapter Isometric stretching is a type of static stretching meaning it does not use motion which involves the resistance of muscle groups through isometric contractions tensing of the stretched muscles see section Types of Muscle Contractions.
The use of isometric stretching is one of the fastest ways to develop increased static-passive flexibility and is much more effective than either passive stretching or active stretching alone. Isometric stretches also help to develop strength in the "tensed" muscles which helps to develop static-active flexibility , and seems to decrease the amount of pain usually associated with stretching.
The most common ways to provide the needed resistance for an isometric stretch are to apply resistance manually to one's own limbs, to have a partner apply the resistance, or to use an apparatus such as a wall or the floor to provide resistance.
An example of manual resistance would be holding onto the ball of your foot to keep it from flexing while you are using the muscles of your calf to try and straighten your instep so that the toes are pointed. An example of using a partner to provide resistance would be having a partner hold your leg up high and keep it there while you attempt to force your leg back down to the ground. An example of using the wall to provide resistance would be the well known "push-the-wall" calf-stretch where you are actively attempting to move the wall even though you know you can't.
Isometric stretching is not recommended for children and adolescents whose bones are still growing. These people are usually already flexible enough that the strong stretches produced by the isometric contraction have a much higher risk of damaging tendons and connective tissue. Kurz strongly recommends preceding any isometric stretch of a muscle with dynamic strength training for the muscle to be stretched. A full session of isometric stretching makes a lot of demands on the muscles being stretched and should not be performed more than once per day for a given group of muscles ideally, no more than once every 36 hours.
The proper way to perform an isometric stretch is as follows: Assume the position of a passive stretch for the desired muscle. Next, tense the stretched muscle for seconds resisting against some force that will not move, like the floor or a partner. Finally, relax the muscle for at least 20 seconds. Some people seem to recommend holding the isometric contraction for longer than 15 seconds, but according to SynerStretch the videotape , research has shown that this is not necessary.
So you might as well make your stretching routine less time consuming. How Isometric Stretching Works How Isometric Stretching Works Isometric Stretching : beginning of section Recall from our previous discussion see section How Muscles Contract that there is no such thing as a partially contracted muscle fiber: when a muscle is contracted, some of the fibers contract and some remain at rest more fibers are recruited as the load on the muscle increases.
Similarly, when a muscle is stretched, some of the fibers are elongated and some remain at rest see section What Happens When You Stretch. During an isometric contraction, some of the resting fibers are being pulled upon from both ends by the muscles that are contracting. The result is that some of those resting fibers stretch!
Normally, the handful of fibers that stretch during an isometric contraction are not very significant. The true effectiveness of the isometric contraction occurs when a muscle that is already in a stretched position is subjected to an isometric contraction.
In this case, some of the muscle fibers are already stretched before the contraction, and, if held long enough, the initial passive stretch overcomes the stretch reflex see section The Stretch Reflex and triggers the lengthening reaction see section The Lengthening Reaction , inhibiting the stretched fibers from contracting. At this point, according to SynerStretch , when you isometrically contracted, some resting fibers would contract and some resting fibers would stretch.
Furthermore, many of the fibers already stretching may be prevented from contracting by the inverse myotatic reflex the lengthening reaction and would stretch even more. When the isometric contraction is completed, the contracting fibers return to their resting length but the stretched fibers would remember their stretched length and for a period of time retain the ability to elongate past their previous limit. This enables the entire muscle to stretch beyonds its initial maximum and results in increased flexibility.
The reason that the stretched fibers develop and retain the ability to stretch beyond their normal limit during an isometric stretch has to do with the muscle spindles see section Proprioceptors : The signal which tells the muscle to contract voluntarily, also tells the muscle spindle's intrafusal muscle fibers to shorten, increasing sensitivity of the stretch reflex.
This mechanism normally maintains the sensitivity of the muscle spindle as the muscle shortens during contraction. This allows the muscle spindles to habituate become accustomed to an even further-lengthened position. PNF Stretching Isometric Stretching : previous section Types of Stretching : beginning of chapter PNF stretching is currently the fastest and most effective way known to increase static-passive flexibility.
PNF is an acronym for proprioceptive neuromuscular facilitation. It is not really a type of stretching but is a technique of combining passive stretching see section Passive Stretching and isometric stretching see section Isometric Stretching in order to achieve maximum static flexibility. Actually, the term PNF stretching is itself a misnomer. PNF was initially developed as a method of rehabilitating stroke victims.
PNF refers to any of several post-isometric relaxation stretching techniques in which a muscle group is passively stretched, then contracts isometrically against resistance while in the stretched position, and then is passively stretched again through the resulting increased range of motion. PNF stretching usually employs the use of a partner to provide resistance against the isometric contraction and then later to passively take the joint through its increased range of motion.
It involves the active tightening of your muscles and moving your joints through their full range of motion throughout the stretch. These functional and sport-specific movements help increase muscle temperature and decrease muscle stiffness. Dynamic stretches should be used as part of your warm-up routine before any athletic event, whether competitive or not. A complete athletic warm-up should incorporate about 5 to 10 minutes of low- to moderate-intensity swimming, jogging or cycling, followed by dynamic stretching.
Stand with your feet facing forward, as wide as your shoulders, and your arms by your side with a degree bend in your elbows. Keep your feet in the same position and in a controlled manner, twist your torso from one side to the other. Be sure to move through your trunk and do not force the movement.
This exercise helps keep your spine mobile and flexible. Maintaining spine flexibility is particularly beneficial for athletes of throwing and hitting sports such as football, baseball, tennis, hockey and lacrosse.
Stand with your arms on your waist; take a step forward and lunge, keeping your front knee in line with your hip and ankle and lowering your back knee toward the floor without touching. Do not allow your front knee to drive past your front toes. Push off the back leg and step forward with the opposite leg, lunging in the same fashion. Engage your abdominal muscles throughout this exercise to avoid arching your back.
This helps stretch the gluteus, hamstring and hip flexor muscles and is beneficial for all athletes, particularly those playing track-and-field sports, soccer, rugby or football. Stand on one leg and in a slow, controlled motion swing the other leg in front of you and behind you through the full range of motion. Make sure to engage your abdominal muscles to prevent your back from arching. This stretch helps prepare the hamstrings and hip flexors for running. Static stretching requires you to move a muscle as far as it can go without feeling any pain, then hold that position for 20 to 45 seconds.
This warms your muscles and increases blood flow to them. Sam Ashe-Edmunds has been writing and lecturing for decades. He has worked in the corporate and nonprofit arenas as a C-Suite executive, serving on several nonprofit boards.
He is an internationally traveled sport science writer and lecturer. Edmunds has a bachelor's degree in journalism. Stretching Exercises for Netball. Share on Facebook. Ballistic Stretching Ballistic stretching occurs when you perform repeated, rapid movements that stretch your muscles slightly past their comfortable range of motion. Static Stretching Static stretching also requires you to move your muscle just past their comfortable range of motion, but instead of quickly retracting the stretch, you hold it steady for 20 to 30 seconds.
Benefits Static stretching helps lengthen muscles after they have been shortened during physical activity.
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