Is stretching good? is it bad?
Stretching is a common component of warm-up and cool-down routines in both amateur and professional sports. However, its effectiveness is often debated. This article explores the types of stretching, their benefits, and current evidence regarding their impact on performance and recovery. For the ones who may want to dig a bit deeper, you will find the different types of stretching and their explanation at the end of the article.
Static stretching after the session?
Most people stretch after a session because they believe it will enhance recovery (American Heart Association, 2020; ACSM, 2021), but reviews and current evidence do not reflect this. (Herbert and Gabriel, 2002; Henschke and Lin, 2011; Herbert et al., 2011; Torres et al., 2012; Baxter et al., 2017). Therefore, if the only goal of stretching after a session is to improve the recovery process, current evidence suggests that we may be wasting our time.
A systematic review that includes 11 randomized controlled trials (RCTs), assessed the effects of stretching on post-exercise recovery markers (1 hour after the session, 24 hours, 48 hours and 72 hours) including DOMS, strength and range of motion (Alfonso et al., 2021). Compared to passive recovery (such as rest) or other methodologies (such as low-intensity cycling or immersion in cold water), static stretches did not show superior benefits, contrasting with the current existing guidelines.
Do you stretch statically before the session?
Current evidence indicates that if the goal of the session is power (such as the improvement of vertical jump), strength, or some speed activity, static stretches can impair subsequent training. If you decide to do them anyway, their negative effects can be mitigated if you perform dynamic stretching after the static stretching.
One disadvantage that this entails is that the warm-up routine will require more time, which may negatively affect adherence to this type of protocol, especially for people who have less time or who simply don’t want to invest extra time.
Static stretching for 30 seconds or less does not have a negative effect on performance, but it also has little effect on improving the range of motion.
It seems the ideal duration to improve range of motion, if that’s the goal, is between 1 and 3 minutes holding the stretch. You don’t have to feel pain but controlled discomfort while performing it. This will allow you to reduce the activation of a protective mechanism which is activated when the muscle is stretched, known as the “myotatic reflex” (it will be activated more or less depending on the speed of the stretch and how much a muscle has been stretched) and it will activate another mechanism known as “autogenic inhibition”, process which is activated when a muscle is under pressure for a certain period of time, giving the signal to the muscle that it is safe to allow that degree of stretch and as a result, improving its the range of motion.
It has been demonstrated the positive or neutral effect of dynamic stretching (movements controlled without rebound) on subsequent performance.
Ballistic stretching (with little control and with a rebound), on the other hand, seems to be less effective than dynamic stretching due to the use of the rebound and the higher risk of injury.
It is important to always include the type of stretching, duration of the stretch in seconds, frequency of stretching, speed and range of motion when we want to apply them in the program. In high-performance sports, we have to be cautious of how we use stretching. It is important to consider that even a little effect may negatively affect the final result of the competition (Chaabene et al.,2019)
The Hold-Relax-Contract (HRC), also known as Contract-Relax-Antagonist-Contract (CRAC), is often considered the most effective PNF stretching technique for improving flexibility. This method combines the benefits of both isometric and dynamic contractions to achieve greater increases in muscle length and flexibility. Two main reasons why it is particularly effective:
1. Enhanced Stretch Reflex Inhibition:
Initial passive stretch, followed by an isometric contraction of the target muscle (agonist), and then a contraction of the opposing muscle (antagonist). This sequence helps to maximally inhibit the stretch reflex, allowing for a greater range of motion.
2. Reciprocal Inhibition:
Contracting the antagonist muscle during the final phase of the stretch induces reciprocal inhibition, which further relaxes the target muscle and allows for a deeper stretch.
Alternatives to improve flexibility
At different levels, strength training both eccentric and concentric with the maximum range of motion and plyometric causes changes in the length of the muscle fascicle, pennation angle and tendon extensibility, which, as a result, may increase the range of motion (Reeves et al., 2009; Kubo et al., 2017; Valamatos et al., 2018; Gérard et al., 2020; Marušiˇc et al., 2020).
Having to stretch as a must to reduce injury risk does not make so much sense, as there are other ways to improve flexibility, including strength training (Saraiva et al., 2014; Nuzzo, 2020; Afonso et al., 2021b). A systematic review by Behm et al. (2016) showed no clear difference between the effects of static or PNF stretching in reducing injury risk.
To this date, there have been several investigations about the relationship between stretching and reducing the risk of injury and it has not been possible to prove that to be true.
So, Do I or Do not?
Stretching is one of the many options we have. It’s neither good nor bad to perform them, what matters the most is to know the adaptations we are looking for.
To do it or not and when will all depend on the type of stretching, goal, period of the season for athletes, time availability and if the person likes it or not (as long as it does not interfere with the objective of the session).
Probably, the part of the program where we perform static stretching can have other positive effects for the development of the session, since it gives the person more time to prepare mentally and physically for the next part while allowing socializing with the rest of the people, creating a stronger adherence to the program.
More info on stretching:
Static Stretching:
Active: Involves holding a position using your muscle strength to feel the tension.
Passive: Requires a partner to hold the position for you.
Dynamic Stretching:
Active: Involves moving limbs through their full range of motion repeatedly.
Ballistic: Uses fast, uncontrolled movements with a bounce at the end.
Controlled Dynamic: Uses smooth, controlled movements to stretch muscles.
Proprioceptive Neuromuscular Facilitation (PNF):
This is a method that uses both stretching and contracting of the targeted muscle groups. The main types of PNF stretching include:
1. Hold-Relax (HR):
Passive stretch held for about 10 seconds. The muscle is then isometrically contracted against resistance for 6-10 seconds, followed by a relaxation phase where the muscle is passively stretched again, often allowing for a greater range of motion.
2. Contract-Relax (CR):
Similar to Hold-Relax, this method involves passively stretching the muscle, then having the individual perform a concentric contraction (shortening of the muscle) against resistance through its full range of motion. After the contraction, the muscle is again passively stretched.
3. Hold-Relax-Contract (HRC) or Contract-Relax-Antagonist-Contract (CRAC):
This technique is an extension of the Hold-Relax method. After the isometric contraction and relaxation phase, the opposing muscle group (antagonist) is contracted to facilitate further stretch of the target muscle. For example, after stretching and contracting the hamstrings, the quadriceps are contracted to deepen the stretch of the hamstrings.
References
Afonso, J., Clemente, F. M., Nakamura, F. Y., Morouço, P., Sarmento, H., Inman, R. A., & Ramirez-Campillo, R. (2021). The effectiveness of post-exercise stretching in short-term and delayed recovery of strength, range of motion and delayed onset muscle soreness: a systematic review and meta-analysis of randomized controlled trials. Frontiers in physiology, 12, 553.
Afonso, J., Olivares-Jabalera, J., & Andrade, R. (2021). Time to move from mandatory stretching? We need to differentiate “Can I?” from “Do I have to?”. Frontiers in Physiology, 1110.
Afonso, J., Ramirez-Campillo, R., Moscão, J., Rocha, T., Zacca, R., Martins, A., & Clemente, F. M. (2021, April). Strength Training versus stretching for improving range of motion: A systematic review and meta-analysis. In Healthcare (Vol. 9, No. 4, p. 427). Multidisciplinary Digital Publishing Institute.
Ferreira-Júnior, J. B., Benine, R. P., Chaves, S. F., Borba, D. A., Martins-Costa, H. C., Freitas, E. D. & Bottaro, M. (2021). Effects of static and dynamic stretching performed before resistance training on muscle adaptations in untrained men. Journal of strength and conditioning research, 35(11), 3050-3055.
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Opplert, J., & Babault, N. (2018). Acute effects of dynamic stretching on muscle flexibility and performance: an analysis of the current literature. Sports Medicine, 48(2), 299-325.
Reid, J. C., Greene, R., Young, J. D., Hodgson, D. D., Blazevich, A. J., & Behm, D. G. (2018). The effects of different durations of static stretching within a comprehensive warm-up on voluntary and evoked contractile properties. European journal of applied physiology, 118(7), 1427-1445.
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