Stretching

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Samira Mustafaeva, Russian rhythmic gymnast Samira Mustafaeva Moskva.jpg
Samira Mustafaeva, Russian rhythmic gymnast
A stretching Siberian tiger Siberian Tiger by Malene Th.jpg
A stretching Siberian tiger

Stretching is a form of physical exercise in which a specific muscle or tendon (or muscle group) is deliberately expanded and flexed in order to improve the muscle's felt elasticity and achieve comfortable muscle tone. [1] The result is a feeling of increased muscle control, flexibility, and range of motion. Stretching is also used therapeutically to alleviate cramps and to improve function in daily activities by increasing range of motion. [2] [3]

Contents

In its most basic form, stretching is a natural and instinctive activity; it is performed by humans and many other animals. It can be accompanied by yawning. Stretching often occurs instinctively after waking from sleep, after long periods of inactivity, or after exiting confined spaces and areas. In addition to vertebrates (i.e. mammals and birds), spiders have also been found to exhibit stretching. [4] [5]

Increasing flexibility through stretching is one of the basic tenets of physical fitness. It is common for athletes to stretch before (for warming up) and after exercise in an attempt to reduce risk of injury and increase performance. [6] :42

Stretching can be dangerous when performed incorrectly. There are many techniques for stretching in general, but depending on which muscle group is being stretched, some techniques may be ineffective or detrimental, even to the point of causing hypermobility, instability, or permanent damage to the tendons, ligaments, and muscle fiber. [7] The physiological nature of stretching and theories about the effect of various techniques are therefore subject to heavy inquiry.

Although static stretching is part of some warm-up routines, pre-exercise static stretching usually reduces an individual's overall muscular strength and maximal performance, regardless of an individual's age, sex, or training status. [8] For this reason, an active dynamic warm-up is recommended before exercise in place of static stretching. [9] [10] [11]

Physiology

Studies have shed light on the function, in stretching, of a large protein within the myofibrils of skeletal muscles named titin. [12] A study performed by Magid and Law demonstrated that the origin of passive muscle tension (which occurs during stretching) is actually within the myofibrils, not extracellularly as had previously been supposed. [13] Due to neurological safeguards against injury such as the Golgi tendon reflex, it is normally impossible for adults to stretch most muscle groups to their fullest length without training due to the activation of muscle antagonists as the muscle reaches the limit of its normal range of motion. [7]

Psychology

Stretching has been recognized for its potential to positively influence both cognitive function and mood. Research indicates that engaging in stretching exercises may lead to a reduction in feelings of anxiety, depression, hostility, fatigue, and confusion, particularly among individuals with sedentary lifestyles. These improvements in mood have been observed to correlate with enhancements in cognitive function. For individuals who often spend prolonged periods engaged in sedentary activities, integrating stretching into their daily routines may prove beneficial. Doing so not only addresses physical tension but also promotes mental well-being. Regular stretching has been associated with decreased levels of anxiety and depression, alongside increased vigor, which could activate brain regions associated with improved cognitive abilities. [14]

Types of stretches

Stretches can be either static or dynamic. Static stretches are performed while stationary and dynamic stretches involve movement of the muscle. Stretches can also be active or passive, where active stretches use internal forces generated by the body to perform a stretch and passive stretches involve forces from external objects or people to perform the stretch. [15] They can involve both passive and active components. [16]

Dynamic stretching

Dynamic stretching is a movement-based stretch aimed at increasing blood flow throughout the body while also loosening up the muscle fibers. Standard dynamic stretches typically involve slow and controlled active contraction of muscles. An example of such a dynamic stretch is lunges. Another form of dynamic stretching is ballistic stretching, which is an active stretch that involves bouncing or swinging back and forth at a high speed in order to take a muscle beyond its typical range of motion using momentum. Ballistic stretching can also be performed with tools such as resistance bands to increase the intention between sets in order to quickly warm-up the body. [17] Ballistic stretching may cause damage to the joints. [16]

Static stretching

The simplest static stretches are static–passive stretches, according to research findings. This brings the joint to its end range of motion and hold it there using external forces. There are more advanced forms of static stretching, such as proprioceptive neuromuscular facilitation (PNF), which involves both active muscle contractions and passive external forces. [6] :42 PNF stretching utilizes an aspect of neuromuscular reeducation, which may yield better results than regular static stretching in terms of induced strength. [18] PNF stretching may involve contracting either the antagonist muscles, agonist muscles, or both (CRAC). [19] The efficacy of PNF stretching and its recommendation of use may be dependent on stretching-to-performance duration. [18]

Effectiveness

A roller derby athlete stretching 06 12 08 Roller Dolls 003.jpg
A roller derby athlete stretching

Stretching has been found both effective and ineffective based on its application for treatment.

Although many people engage in stretching before or after exercise, the medical evidence has shown this has no meaningful benefit in preventing specifically muscle soreness. It may reduce the lactic acid build up in the muscles, making the next workout more bearable. [20]

Stretching does not appear to reduce the risk of injury during exercises, except perhaps a dynamic warm-up for runners. While running places extreme stress loads on the joints, static stretching can help to improve joint flexibility. However, this has not been proven to reduce risk of injury in the runners. A dynamic (stretching) warm up has been shown to help overall running performance. [21]

Delayed onset muscle soreness, also known as DOMS, typically arises 48 hours after an exercise bout. Stretching before or after the exercise did not show any significant benefits in the onset of DOMS. [22]

Effectiveness of Dynamic Stretching

Ballistic stretching, a form of dynamic stretching, is likely to increase flexibility through a neurological mechanism. The stretched muscle is moved passively to the end range by an external force or agonist muscle: holding a muscle in this position might reduce muscle spindle sensitivity, with repeated stretch applied at the end range inhibiting the Golgi tendon organ. [23]

Dynamic stretching, because it is movement-based, may not isolate the muscle group as well or have as intense of a stretch, but it is better at increasing the circulation of blood flow throughout the body, which in turn increases the amount of oxygen able to be used for athletic performance. This type of stretching has shown better results on athletic performances of power and speed when compared to static stretching. [24]

Effectiveness of Static Stretching

Static stretching is better at creating a more intense stretch because it is able to isolate a muscle group better. [25] But this intensity of stretching may hinder one's athletic performance because the muscle is being overstretched while held in this position and, once the tension is released, the muscle will tend to tighten up and may actually become weaker than it was previously. [26] It has been shown in high level athletes, such as gymnasts, after performing a static stretching routine that it has a negative effect. The gymnasts lost the ability to jump vertically as high as prior as well as no improvement in their straddle jump or flexibility. [27] Also, the longer the duration of static stretching, the more exhausted the muscle becomes. This type of stretching has been shown to have negative results on athletic performance within the categories of power and speed. [28] [29] [30] [31] However, to be able to do usual daily activities, a certain amount of range of motion is needed from each muscle. For example, the calf muscles are one of the muscle groups that have the most need for adequate flexibility since they are deeply related to normal lower limb function. When the goal is to increase flexibility, the most commonly used technique is stretching. Chronic static stretching was shown to increase range of motion of Dorsiflexion or bringing one's foot closer to their shin by an average of 5.17 degrees in healthy individuals versus 3.77 degrees when solely using ballistic stretching. [3] While static stretching is shown to decrease power and speed in higher level athletes, when it comes to the older population who live more sedentary lifestyles static stretching has been shown to increase muscles strength and power. [32]

Dynamic versus Static: Flexibility and Performance

Both dynamic and static stretching have been shown to have a positive impact on flexibility over time by increasing muscle and joint elasticity, thus increasing the depth and range of motion an athlete is able to reach. [33] This is evident in the experiment "Acute effects of duration on sprint performance of adolescent football players". [33] In this experiment, football players were put through different stretching durations of static and dynamic stretching to test their effects. They were tested on maximum sprinting ability and overall change in flexibility. Both static and dynamic stretching had a positive impact on flexibility but, whereas dynamic stretching had no impact on sprint times, static stretching had a negative result, worsening the time the participants were able to sprint the distance in. [34]

See also

Related Research Articles

<span class="mw-page-title-main">Rotator cuff</span> Group of muscles

The rotator cuff is a group of muscles and their tendons that act to stabilize the human shoulder and allow for its extensive range of motion. Of the seven scapulohumeral muscles, four make up the rotator cuff. The four muscles are:

<span class="mw-page-title-main">Sprain</span> Damage to one or more ligaments in a joint

A sprain is a soft tissue injury of the ligaments within a joint, often caused by a sudden movement abruptly forcing the joint to exceed its functional range of motion. Ligaments are tough, inelastic fibers made of collagen that connect two or more bones to form a joint and are important for joint stability and proprioception, which is the body's sense of limb position and movement. Sprains may be mild, moderate, or severe, with the latter two classes involving some degree of tearing of the ligament. Sprains can occur at any joint but most commonly occur in the ankle, knee, or wrist. An equivalent injury to a muscle or tendon is known as a strain.

<span class="mw-page-title-main">Exercise physiology</span>

Exercise physiology is the physiology of physical exercise. It is one of the allied health professions, and involves the study of the acute responses and chronic adaptations to exercise. Exercise physiologists are the highest qualified exercise professionals and utilise education, lifestyle intervention and specific forms of exercise to rehabilitate and manage acute and chronic injuries and conditions.

Delayed onset muscle soreness (DOMS) is the pain and stiffness felt in muscles after unaccustomed or strenuous exercise. The soreness is felt most strongly 24 to 72 hours after the exercise. It is thought to be caused by eccentric (lengthening) exercise, which causes small-scale damage (microtrauma) to the muscle fibers. After such exercise, the muscle adapts rapidly to prevent muscle damage, and thereby soreness, if the exercise is repeated.

<span class="mw-page-title-main">Warming up</span> Part of stretching and preparation before performing a physical activity

'Warming up' is a part of stretching and preparation for physical exertion or a performance by exercising or practicing gently beforehand, usually undertaken before a performance or practice. Athletes, singers, actors and others warm up before stressing their muscles. It is widely believed to prepare the muscles for vigorous actions and to prevent muscle cramps and injury due to overexertion.

Cryotherapy, sometimes known as cold therapy, is the local or general use of low temperatures in medical therapy. Cryotherapy may be used to treat a variety of tissue lesions. The most prominent use of the term refers to the surgical treatment, specifically known as cryosurgery or cryoablation. Cryosurgery is the application of extremely low temperatures to destroy abnormal or diseased tissue and is used most commonly to treat skin conditions.

Overtraining occurs when a person exceeds their body's ability to recover from strenuous exercise. Overtraining can be described as a point where a person may have a decrease in performance and plateauing as a result of failure to consistently perform at a certain level or training load; a load which exceeds their recovery capacity. People who are overtrained cease making progress, and can even begin to lose strength and fitness. Overtraining is also known as chronic fatigue, burnout and overstress in athletes. It is suggested that there are different variations of overtraining, firstly monotonous program over training suggest that repetition of the same movement such as certain weight lifting and baseball batting can cause performance plateau due to an adaption of the central nervous system which results from a lack of stimulation. A second example of overtraining is described as chronic overwork type training where the subject may be training with too high intensity or high volume and not allowing sufficient recovery time for the body. Up to 10% of elite endurance athletes and 10% of American college swimmers are affected by overtraining syndrome.

<span class="mw-page-title-main">Strength training</span> Performance of physical exercises designed to improve strength

Strength training, also known as weight training or resistance training, involves the performance of physical exercises that are designed to improve strength and endurance. It is often associated with the lifting of weights. It can also incorporate a variety of training techniques such as bodyweight exercises, isometrics, and plyometrics.

Manual therapy, or manipulative therapy, is a physical treatment primarily used by physical therapists, occupational therapists to treat musculoskeletal pain and disability; it mostly includes kneading and manipulation of muscles, joint mobilization and joint manipulation. It is also used by Rolfers, massage therapists, athletic trainers, osteopaths, and physicians.

<span class="mw-page-title-main">Cooling down</span> Transition to a lower activity level in physical exercise

Cooling down is the transition from intense physical activity to a more typical activity level. Depending on the intensity of the exercise, cooling down after a workout method, such as intense weightlifting, can involve a slow jog or walk.

Range of motion (ROM) is when a person has become injured in some way, most times the doctor's advice the patients to exercise and stretch the back muscles. For this purpose a form of exercises called range of motion exercises which are used to keep the muscles and joints in the patients back strong and flexible. These exercises can be done by the patient himself, or with a physical therapist. If these exercises are done alone they would be called active range of motion (AROM) exercises and if they require assistance they would be called active-assisted range of motion (AAROM) exercises.

Hypertonia is a term sometimes used synonymously with spasticity and rigidity in the literature surrounding damage to the central nervous system, namely upper motor neuron lesions. Impaired ability of damaged motor neurons to regulate descending pathways gives rise to disordered spinal reflexes, increased excitability of muscle spindles, and decreased synaptic inhibition. These consequences result in abnormally increased muscle tone of symptomatic muscles. Some authors suggest that the current definition for spasticity, the velocity-dependent over-activity of the stretch reflex, is not sufficient as it fails to take into account patients exhibiting increased muscle tone in the absence of stretch reflex over-activity. They instead suggest that "reversible hypertonia" is more appropriate and represents a treatable condition that is responsive to various therapy modalities like drug or physical therapy.

<span class="mw-page-title-main">Flexibility (anatomy)</span> Anatomical range of movement of a joint or series of joints

Flexibility is the anatomical range of movement in a joint or series of joints, and length in muscles that cross the joints to induce a bending movement or motion. Flexibility varies between individuals, particularly in terms of differences in muscle length of multi-joint muscles. Flexibility in some joints can be increased to a certain degree by exercise, with stretching a common exercise component to maintain or improve flexibility.

<span class="mw-page-title-main">Sprained ankle</span> Medical condition

A sprained ankle is an injury where sprain occurs on one or more ligaments of the ankle. It is the most commonly occurring injury in sports, mainly in ball sports such as basketball, volleyball, football, and tennis.

<span class="mw-page-title-main">Outline of exercise</span> Overview of and topical guide to exercise

The following outline is provided as an overview of and topical guide to exercise:

Aquatic therapy refers to treatments and exercises performed in water for relaxation, fitness, physical rehabilitation, and other therapeutic benefit. Typically a qualified aquatic therapist gives constant attendance to a person receiving treatment in a heated therapy pool. Aquatic therapy techniques include Ai Chi, Aqua Running, Bad Ragaz Ring Method, Burdenko Method, Halliwick, Watsu, and other aquatic bodywork forms. Therapeutic applications include neurological disorders, spine pain, musculoskeletal pain, postoperative orthopedic rehabilitation, pediatric disabilities, pressure ulcers, and disease conditions, such as osteoporosis.

Eccentric training is a type of strength training that involves using the target muscles to control weight as it moves in a downward motion. This type of training can help build muscle, improve athletic performance, and reduce the risk of injury. An eccentric contraction is the motion of an active muscle while it is lengthening under load. Eccentric training is repetitively doing eccentric muscle contractions. For example, in a biceps curl the action of lowering the dumbbell back down from the lift is the eccentric phase of that exercise – as long as the dumbbell is lowered slowly rather than letting it drop.

Fascia training describes sports activities and movement exercises that attempt to improve the functional properties of the muscular connective tissues in the human body, such as tendons, ligaments, joint capsules and muscular envelopes. Also called fascia, these tissues take part in a body-wide tensional force transmission network and are responsive to training stimulation.

<span class="mw-page-title-main">Foam roller</span> Therapeutic exercise device

A foam roller is a lightweight, cylindrical tube of compressed foam. It may be used for many reasons, including increasing flexibility, reducing soreness, and eliminating muscle knots. Foam rolling is a method of self-myofascial release. Foam rollers have a short term positive impact in the range of motion of joints, but long term performance or range of motion benefits are unknown. Combining foam rolling and stretching does not cause a significant impact in range of motion compared to only foam rolling or stretching, but does have a superior effect in performance only if stretching is done after foam rolling. A 2021 analysis of studies concluded that "evidence seems to justify the widespread use of foam rolling as a warm-up activity rather than a recovery tool" while arguing that post exercise or recovery rolling reduced muscle pain perception. A 2019 review concluded that 90 seconds of foam rolling per muscle group may be the minimum needed to achieve a reduction in muscle pain or soreness in the short term but that there is insufficient evidence for the optimal amount.

Nerve glide, also known as nerve flossing or nerve stretching, is an exercise that stretches nerves. It facilitates the smooth and regular movement of peripheral nerves in the body. It allows the nerve to glide freely along with the movement of the joint and relax the nerve from compression. Nerve gliding cannot proceed with injuries or inflammations as the nerve is trapped by the tissue surrounding the nerve near the joint. Thus, nerve gliding exercise is widely used in rehabilitation programs and during the post-surgical period.

References

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Further reading