Stretching has long been ingrained into us as an activity to do before and after exercise, sport or other physical activities. The reasons to do so are varied and plentiful but does stretching actually benefit us in any way? And if so, what can we do to maximise the benefits of stretching?
There are 4 broad types of stretching:
- Static – One of the most popular forms of stretching – it involves holding the stretched muscle for an extended period of time.
- Dynamic – Another very common stretching technique – involves controlled but exaggerated, often sports specific movements.
- Ballistic – Involves repetitive bouncing movements. Performed at a faster rate and in a more uncontrolled manner than dynamic stretching.
- PNF – Short for proprioceptive neuromuscular facilitation – is a type of stretch that involves a partner actively stretching you in order to activate the golgi tendon organs which helps to relax a muscle after a sustained contraction.
From the list above, ballistic stretches are often seen as quite dangerous due to its uncontrolled manner and may cause overstretching of the muscles and ligaments. PNF stretches require a partner, which may hinder its use in an everyday environment.
Benefits of Stretching
Stretching a muscle, either acutely (short-term) or chronically (long-term) can possibly affect several factors including:
- Sports Performance
- Injury Risk
- Injury Recovery
- Muscle Soreness
Stretching & Flexibility
Flexibility is an important part of a well rounded approach to fitness. Being flexible later in life will help with balance and other health related quality of life measures as poor flexibility inhibits movement. Flexibility is also a trademark of several sports such as gymnastics, dancing and even hurdling. Results from studies are somewhat contradictory, but acute static1,2,3,4, dynamic3 and ballistic2 stretching have all been shown to help with increasing flexibility and dynamic range of motions. Static stretching has been studied the most with significant positive results. All forms of chronic stretching (static5,6,7, dynamic5, ballistic6 and PNF5) have been shown to result in increases in flexibility lasting for up to a day post stretch to long term sustained changes.
Stretching & Strength
Strength is vital in many sports and especially in the gym. Improvements in strength can help boost your workouts helping you lift more and place your muscles under greater strain to promote muscle adaptations. Several studies have looked at stretching and its ability to affect strength. Acute stretching seems to negatively affect strength performance, especially maximal strength8,9,10,11, however, chronic stretching programs may be able to improve strength through stretch related hypertrophy (muscle growth) which has been shown in animals.11 Other studies have been able to show that acute dynamic stretching has no effect on strength and can even increase strength (even after only 30 seconds worth).12,13
Stretching & Endurance
Muscular endurance is important in several sports such as long distance running and even during weight training programs focused on cutting down. As a result, it is important that activities we perform prior to exercise do not negatively effect our endurance capacity. Studies have shown however that acute stretching can reduce our muscular endurance14,15. The latter study was able to show decreases in bench press performance. Chronic stretching (static and dynamic) on the other hand is able to improve muscular endurance capacity.16
Stretching & Sports Performance
Sports performance is of course sports specific. Depending on the sport, improvements in performance can be due to changes in strength, speed, endurance, skill or other factors. Judging from the above studies, stretching can positively impact sports performance through changes in flexibility, strength and endurance. This has been backed up by the 2004 review18 showing that while acute stretching does not improve muscular force or jump height, regular stretching can improve muscular force, jump height, and speed. Other studies have been shown to support regular uses of static and ballistic stretches6,17,19 to improve performance and even acute dynamic stretching.19
Stretching & Injury Risks
Injuries are sports, exercise and movement specific. As such, stretching before particular sports or exercises can be both beneficial and detrimental. For example, in terms of running, over stretching a joint can cause a reduction in joint integrity which can lead to sprains. Conversely however, stretching can elongate a muscle which can counteract the excessive forces of an exercise in overstretching the muscle, thus preventing strains.20 Several reviews on the topic have shown that there is insufficient evidence to support the use or disuse of stretching as a way to prevent injuries.21,22,23 One important point to note is that for exercises and sports which require abrupt changes in speed and direction (basketball, football, tennis, etc) will consist of many stretch shorten cycles. Stretching pre-exercise will benefit these exercises and sports the most due its ability to help increase tendon compliance which will help with the storage and release of large amounts of energy.
Stretching & Injury Recovery
In terms of injury recovery, there is some evidence that stretching can help promote faster recovery from certain injuries. Two studies24,25 were able to show faster recovery from hamstring strains and plantar fasciitis with concurrent increases in range of motion and decreases in pain and stiffness.
Stretching & DOMS
DOMS (delayed onset muscle soreness) is the most common muscle related pain. While generally not damaging, it is unpleasant and can impair performance. A 2006 review26 of studies looking at stretching and its effects on DOMS showed that there was a small but insignificant effect of stretching on the reduction of DOMS. Stretching post exercise was able to reduce the soreness scale of DOMS by only 1 point out of 100 compared to pre-exercise stretching which only reduced 0.5 points.
Stretching - Recommendations
The huge amount of studies out there looking at all types and variations of stretching protocols no doubt make it hard to figure out what is the best stretching program to incorporate into your workout. So to make it easier for you, here are some tips:
- Static stretching is not recommended before exercises which require strength.
- Stretching before exercise or sports is NOT recommended if endurance capacity is required.
- If you must stretch before exercises or sports – use dynamic stretches.
- Stretching before exercise or sports may be beneficial for sports which require high flexibility or fast changes in speed or direction – but be aware with slight losses with strength and endurance capacity. Also be aware that the increase in flexibility may be short term and constant stretching will be required to maintain flexibility.
- Static and PNF stretches should be held between 10-30 seconds.
- Ballistic and dynamic stretches can be done longer but should be ideally < 2 mins to prevent excessive strain on the joint.
- Long term stretching programs lasting between 20 mins - 1hr can help improve flexibility, strength, endurance and sports performance.
- Stretching before exercise may be able to prevent injury but is dependent on the exercise or sport.
- Stretching programs will help with injury recovery but has little effect on DOMS.
- Never stretch before muscles are properly warmed up.
- Stretching should not be a painful experience.
2 Bacurau RF, Monteiro GA, Ugrinowitsch C, Tricoli V, Cabral LF, Aoki MS. ‘Acute effect of a ballistic and a static stretching exercise bout on flexibility and maximal strength.’ J Strength Cond Res. 2009 Jan;23(1):304-8.
3 Amiri-Khorasani M, Abu Osman NA, Yusof A. ‘Acute effect of static and dynamic stretching on hip dynamic range of motion during instep kicking in professional soccer players.’ J Strength Cond Res. 2011 Jun;25(6):1647-52.
4 DePino GM et al. ‘Duration of Maintained Hamstring Flexibility After Cessation of an Acute Static Stretching Protocol.’ J Athl Train. 2000 Jan–Mar; 35(1): 56–59.
5 Lucas RC, Koslow R. ‘Comparative study of static, dynamic, and proprioceptive neuromuscular facilitation stretching techniques on flexibility.’ Percept Mot Skills. 1984 Apr;58(2):615-8.
6 Woolstenhulme MT et al. ‘Ballistic stretching increases flexibility and acute vertical jump height when combined with basketball activity.’ Journal of Strength and Conditioning Research, 2006, 20(4), 799–803
7 Nelson RT and Bandy WD. ‘Eccentric training and static stretching improve hamstring flexibility of high school males.’ J Athl Train. 2004 Jul-Sep; 39(3): 254–258.
8 Kokkonen J et al. ‘Acute muscle stretching inhibits maximal strength performance.’ Res. Q. Exerc. Sport 69:411–415. 1998.
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10 Marek SM et al. ‘Acute Effects of Static and Proprioceptive Neuromuscular Facilitation Stretching on Muscle Strength and Power Output.’ J Athl Train. 2005 Apr-Jun; 40(2): 94–103.
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12 Manoel ME, Harris-Love MO, Danoff JV, Miller TA. ‘Acute effects of static, dynamic, and proprioceptive neuromuscular facilitation stretching on muscle power in women.’ J Strength Cond Res. 2008 Sep;22(5):1528-34.
13 Yamaguchi T, Ishii K. ‘Effects of static stretching for 30 seconds and dynamic stretching on leg extension power.’ J Strength Cond Res. 2005 Aug;19(3):677-83.
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15 Franco BL, Signorelli GR, Trajano GS, de Oliveira CG. ‘Acute effects of different stretching exercises on muscular endurance.’ J Strength Cond Res. 2008 Nov;22(6):1832-7.
16 Herman SL, Smith DT. ‘Four-week dynamic stretching warm-up intervention elicits longer-term performance benefits.’ J Strength Cond Res. 2008 Jul;22(4):1286-97.
17 Kokkonen J, Nelson AG, Eldredge C, Winchester JB. ‘Chronic static stretching improves exercise performance.’ Med Sci Sports Exerc. 2007 Oct;39(10):1825-31.
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24 Malliaropoulos N, Papalexandris S, Papalada A, et al. The role of stretching in rehabilitation of hamstring injuries: 80 athletes follow-up. Med Sci Sports Exerc 2004;36:756-759.
25 Porter D, Barrill E, Oneacre K, et al. The effects of duration and frequency of Achilles tendon stretching on dorsiflexion and outcome in painful heel syndrome: a randomized, blinded, control study. Foot Ankle Int 2002;23:619-624
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