Stretching entails movement of a body segment to a point of resistance in the ROM. At the moment of resistance, a force is utilised. This stretching programme can be done either actively or passively. An active stretch transpires when the person stretching provides the force of the stretch. Throughout the sitting toe touch, for example, the exerciser engages the abdominal muscles and hip flexors to flex the trunk forward to stretch the hamstrings and lower back. A passive stretch arises when a partner or stretching machine offers external force to elicit or heighten a stretch.
A static stretch is slow and continuous with the end point held for thirty seconds. A static stretch comprises the relaxation and simultaneous elongation of the stretched muscle. Because it is completed slowly, static stretching does not stimulate the stretch reflex of the stretched muscle; consequently, the probability of injury is less than that during ballistic stretching. Furthermore, it is easy to absorb and has been revealed to successfully improve ROM. Although injury to muscles or connective tissue might occur if the static stretch is too forceful, there are no real drawbacks to static stretching provided proper technique is used.
A ballistic stretch characteristically involves active muscular exertion and uses a ‘bouncing-type’ movement in which the end point is not held. It is frequently used in the pre-exercise warm-up; yet, it may possibly injure muscles or connective tissues, particularly when there has been a prior injury. Ballistic stretching typically triggers the stretch reflex that does not permit the involved muscles to relax and defeats the purpose of stretching.
A dynamic stretch is a category of functionally-based stretching exercise that utilises sport-specific actions to prepare the body for movement. Dynamic stretching – also termed mobility drills – places a priority on the movement necessities of the sport or activity rather than on separate muscles. This kind of exercise can closely imitate the movement requirements of a sport or activity, for instance, a walking knee lift stretch duplicates the knee lift of a sprinter. In essence, one can think of dynamic stretching as vigorously moving a joint through the ROM necessary for a sport. Dynamic and ballistic stretches may seem similar; however, a number of key variances expressively alter the effects of these activities such that dynamic stretching circumvents the negative effects related to ballistic stretching. Dynamic stretching averts bouncing and is executed in a more meticulous manner than ballistic stretching. The outcome is a controlled ROM that is often lesser than that fashioned by ballistic stretching. As a consequence of the comparable movement patterns in dynamic stretching, it is the favoured method of stretching during a warm-up. In dynamic stretching, unlike static stretching, the muscle does not relax during the stretch but in its place is active through the ROM; this is also more precise to the movements that follow in a sport.It is important to note that even though it is an ideal warm-up activity, it may be less effective than static or PNF stretching at increasing static ROM.
Proprioceptive Neuromuscular Facilitation Stretch (PNF)
PNF stretching was initially established as part of a neuromuscular rehabilitation programme intended to relax muscles with augmented tone or activity. It has since expanded to the realm of increasing flexibility. PNF procedures are typically performed with a partner and encompass both passive movement and active (concentric and isometric) muscle actions. It may be superior to alternative stretching procedures because it enables muscular inhibition, though evidence for this has not been dependably shown. However, PNF stretching is often unfeasible because most of the stretches necessitate a partner and some know-how. During a PNF stretch, three specific muscle activities are used to expedite the passive stretch. Both isometric and concentric muscle actions of the antagonist (the muscle being stretched) are utilised before a passive stretch of the antagonist to attain autogenic inhibition. The isometric muscle action is referred to as hold and the concentric muscle feat as contract. A concentric muscle action of the agonist, entitled agonist contraction, is utilised during a passive stretch of the antagonist to realise reciprocal inhibition. Each method also involves passive, static stretches that are referred to as relax. There are three elementary kinds of PNF stretching techniques: hold-relax, contract-relax, and hold-relax with agonist contraction. Out of the three, hold-relax with agonist contraction is the most effective and efficient.The properties of these three techniques require another article of coverage, which will be provided soon!
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