Stretching is a form of physical exercise in which a specific muscle or tendon (or muscle group)
is deliberately flexed or stretched 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]
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.
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.[4]: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.[5] The physiological nature of
stretching and theories about the effect of various techniques are therefore subject to heavy
inquiry.
Though static stretching is a part of some pre and post-workout routines, a review article that
was published in January 2020 by the Scandinavian Society of Clinical Physiology and Nuclear
Medicine, indicated that pre-exercise static stretching did in-fact reduce an individuals overall
muscular strength and maximal performance. Furthermore, theses findings present a uniform
effect, regardless of an individuals age, gender, or training status.[6] For this reason, an active
dynamic warm-up is recommended before exercise in place of static stretching.[7][medical citation needed]
Contents
1Physiology
2Types of stretches
o 2.1Dynamic stretching
o 2.2Static stretching
3Effectiveness
4Stretching tools
5References
6Further reading
7External links
Physiology[edit]
Studies have shed light on the function, in stretching, of a large protein within the myofibrils of
skeletal muscles named titin.[8] 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.[9] 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.[5]
Types of stretches[edit]
Stretches can be either static or dynamic, where static stretches are performed while stationary
and dynamic stretches involve movement of the muscle during the stretch. 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 facilitate the
stretch. Stretches can involve both passive and active components.[10]
Football player Luis Suárez stretching prior to a match.
Martin Brodeur stretching on the Devils' bench during warmups.
Assisted stretching may be performed when the athlete is unable to stretch optimally
independently. For example, during cramping of the hamstrings, assistance in stretching out the
muscles may help.
Dynamic stretching[edit]
Dynamic stretching is a movement based stretch aimed on 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 are
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 may cause damage to the joints.
[10]
Static stretching[edit]
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.[4]:42[11] PNF stretching
may involve contracting either the antagonist muscles, agonist muscles, or both (CRAC).[12]
Effectiveness[edit]
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.[13]
Stretching does not appear to reduce the risk of injury during exercises, except perhaps for
runners.[14] There is some evidence that pre-exercise stretching may increase athletes' range of
movement.[14][15]
There are different positives and negatives for the two main types of stretching: static and
dynamic. Static stretching is better at creating a more intense stretch because it is able to isolate
a muscle group better.[citation needed] But this intense of a stretch may hinder one's athletic performance
because the muscle is being over stretched 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.[citation needed] 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.[citation needed] 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 ones 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]
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 an athletic
performance. This type of stretching has shown better results on athletic performances of power
and speed, when compared to static stretching.[16]
However, both of these types of 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.[17] This is evident in the experiment "Acute effects of duration
on sprint performance of adolescent football players". 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. While the duration of stretching for dynamic had no impact on
the overall results, the longer the stretch was held for static, the worse the results got, showing
that the longer the duration of stretching held, the weaker the muscle became.[citation needed]
Stretching tools[edit]
BOSU
Flexcushion
Foam roller
Stretch Band
References[edit]
1. ^ Weerapong, Pornratshanee; Hume, Patria A.; Kolt, Gregory S. (2004). "Stretching:
Mechanisms and Benefits for Sports Performance and Injury Prevention". Physical Therapy
Reviews. 9(4): 189–206. doi:10.1179/108331904225007078.
2. ^ Dagenais, Marc (December 2011) Softball Training Tips – Do you know how to
stretch? softballperformance.com
3. ^ Jump up to:a b Medeiros, Diulian Muniz; Martini, Tamara Fenner (March 2018). "Chronic
effect of different types of stretching on ankle dorsiflexion range of motion: Systematic review and
meta-analysis". Foot (Edinburgh, Scotland). 34: 28–
35. doi:10.1016/j.foot.2017.09.006. ISSN 1532-2963. PMID 29223884.
4. ^ Jump up to:a b Zaffagnini, Stefano; Raggi, Federico; Silvério, Jorge; Espregueira-Mendes,
Joao; di Sarsina, Tommaso Roberti; Grassi, Alberto (2016). "Chapter 4: General Prevention
Principles of Injuries". In Mayr, Hermann O.; Zaffagnini, Stefano (eds.). Prevention of injuries and
overuse in sports : directory for physicians, physiotherapists, sport scientists and coaches.
Springer. ISBN 978-3-662-47706-9.
5. ^ Jump up to:a b Tsatsouline, Pavel (2001). Relax into stretch: instant flexibility through
mastering muscle tension. Dragon Door Publications. ISBN 978-0-938045-28-1.
6. ^ Nunes, João Pedro & Schoenfeld, Brad & Nakamura, Masatoshi & Ribeiro, Alex &
Cunha, Paolo & Cyrino, Edilson. (2020). Does stretch training induce muscle hypertrophy in
humans? A review of the literature. Clinical Physiology and Functional Imaging.
10.1111/cpf.12622.
7. ^ Reasons Not to Stretch New York Times, 2013-04-03.
8. ^ Molecular origin of the hierarchical elasticity of titin: simulation, experiment and theory.
Jen Hsin, Johan Strümpfer, Eric H. Lee, and Klaus Schulten. Annual Review of Biophysics,
40:187-203, 2011.
9. ^ University of California Regents > Muscle Physiology – Types of Contractions.
muscle.ucsd.edu
10. ^ Jump up to:a b Appleton, Brad. "STRETCHING AND FLEXIBILITY: Everything you never
wanted to know". MIT. web.mit.edu. Retrieved 13 June2019.
11. ^ Hindle, KB; Whitcomb, TJ; Briggs, WO; Hong, J (March 2012). "Proprioceptive
Neuromuscular Facilitation (PNF): Its Mechanisms and Effects on Range of Motion and Muscular
Function". Journal of Human Kinetics. 31: 105–13. doi:10.2478/v10078-012-0011-
y. PMC 3588663. PMID 23487249.
12. ^ Hong, Junggi; Briggs, Wyatt; Whitcomb, Tyler; Hindle, Kayla (2012-03-
31). "Proprioceptive Neuromuscular Facilitation (PNF): Its Mechanisms and Effects on Range of
Motion and Muscular Function". J Hum Kinet. 31 (1): 105–113. doi:10.2478/v10078-012-0011-
y. PMC 3588663. PMID 23487249.
13. ^ Herbert RD, de Noronha M, Kamper SJ (2011). "Stretching to prevent or reduce muscle
soreness after exercise". Cochrane Database Syst Rev (Systematic review) (7):
CD004577. doi:10.1002/14651858.CD004577.pub3. PMID 21735398.
14. ^ Jump up to:a b Behm DG, Blazevich AJ, Kay AD, McHugh M (2016). "Acute effects of muscle
stretching on physical performance, range of motion, and injury incidence in healthy active
individuals: a systematic review". Appl Physiol Nutr Metab (Systematic review). 41 (1): 1–
11. doi:10.1139/apnm-2015-0235. PMID 26642915.
15. ^ Page P (2012). "Current concepts in muscle stretching for exercise and
rehabilitation". International Journal of Sports Physical Therapy. 7 (1): 109–
19. PMC 3273886. PMID 22319684.
16. ^ Opplert, J., Babault, N. Acute Effects of Dynamic Stretching on Muscle Flexibility and
Performance: An Analysis of the Current Literature. Sports Med 48, 299–325
(2018). https://doi.org/10.1007/s40279-017-0797-9
17. ^ https://sparklinginfoh.com/2018/12/11/why-stretching-so-important/
Iatridou, G., Dionyssiotis, Y., Papathanasiou, J., Kapetanakis, S., & Galitsanos, S.
(October/December 2018). "Acute effects of stretching duration on sprint performance of
adolescent football players". Muscles, Ligaments & Tendons Journal (MLTJ), 8 (4), 37–
42. doi:10.11138/mltj/2018.8.1.037.
