If you have a look at the internet, you will find millions of pages of stretches of every conceivable muscle or muscle group, with detailed information and a nice picture of all of them. This is the first blog post of a series that will attempt clarify what is the current situation regarding stretching and what we know about them.
Nowadays, what you hear the most is not about the different possible stretches, but whether they are useful or not and, if the answer is affirmative, the way you should stretch. There is also a lot of information on this topic on the internet, although quantity does not mean quality. In this blog post I will give you the necessary information to know what’s true and what should be put aside and forget. As usual, I’ll try to explain it in an understandable way for all, no strange words.
As you know and if you do not know, I tell you, there are different types of stretching. In fact there are more than you might think (if you are not a physio or have a close relationship with the sports and wellbeing world). I am going to start talking about static stretching in this post, as they seem to be the most rejected, although they used to be very popular in the past.
What is static stretching?
Static stretching is, in short, the one where you elongate a muscle or muscle group and hold the position for a certain period of time. The photo below is one example among many that can be found in the stretching section of this blog.
You have always heard, since you were a kid, that stretching is very important before and after exercise. Some people say that only after exercise, others that dynamic stretching before exercise and static stretching after exercise and some people also say that static stretching should be avoided. And what is the reality?, who should we trust?
Now, after this brief introduction, I will explain to you what the “clever guys” * say about static stretching.
* Clever guys: researchers that spend years studying to try and show us, through studies, what are the best things to do to improve health and exercise performance. It is a pity that after so much work, not many people read their studies and prefer to write blog posts based on “popular knowledge and/or urban legend” rather than the mentioned studies.
What do they say about static stretching?
You’ve heard some people saying that these stretches should not be part of our lives, but the reality is that the information experts manage is not so clear, in fact they are somewhat contradictory. Please, note that the studies below are important studies because of its relevance.
In 2008, Small K et al., in the study A systematic review into the efficacy of static stretching as part of a warm-up for the prevention of exercise-related injury, say that static stretching before exercise does not reduce the risk of injuries in general. However, they also say that static stretching could reduce the risk of musculotendinous injuries (tendons and muscles). This might be a bit difficult to understand. If we look at injuries in general, there is evidence that static stretching does not reduce its incidence, although if we look at the musculotendinous injuries only, static stretching might be beneficial.
In 2011, Behm DG et al., in the studio A review of the acute effects of static and dynamic stretching on performance, say that if you play a sport that requires a high degree of static flexibility, you should perform static stretches of short duration and low intensity to reduce the risk of having issues.
In 2012, in the study Does pre-exercise static stretching inhibit maximal muscular performance? A meta-analytical review, Simic L et al. say that static stretching should be avoided. At the time I read this, I jumped for joy (finally a proper answer), but I kept reading and the study analysed static stretching as the only warm-up activity and the shorter duration of stretching the fewer adverse effects. And I wonder, who does a warming-up consisting only of static stretching? The research world is so… complicated.
Also in 2012, the study Effect of acute static stretch on maximal muscle performance: a systematic review by Kay AD et al. talks about the fact that the negative effect of static stretching on muscle activity is mainly limited to longer durations (60 seconds or more) and that pre-exercise static stretching of short duration can be made without compromising muscle performance..
In 2014, The effectiveness of exercise interventions to prevent sports injuries: a systematic review and meta-analysis of randomised controlled trials by Jeppe Bo Lauersen et al. says that there is not beneficial effects for stretching on injury prevention. However, when the studies the above article is based on are analysed, all you can read is that stretching does not offer protection against muscle pain, although evidence regarding stretching and their impact for good or bad in sports injury prevention is not enough and more quality studies are needed. These are the studies: Effects of stretching before and after exercising on muscle soreness and risk of injury: systematic review by Rob D Herbert et al. and The impact of stretching on sports injury risk: a systematic review of the literature by Thacker SB et al.
Also, in 2014, we find a very interesting study Increased range of motion after static stretching is not due to changes in muscle and tendon structures by Konrad A et al. which tells us that the increased joint range of motion might not be due to changes in the muscle-tendon structure, but the increased tolerance to stretching due to the adjustment of the nociceptive nerve endings.
These are my own conclusions which might make you think more about static stretching and the widespread “no static stretching”. My conclusions say as follow:
- Static stretching may not be as bad as many people think.
- They might be useful before certain sports (sports which require high degree of static flexibility such as gymnastics) to prevent certain injuries such as muscle-tendon injuries.
- For those thinking about a possible nerve damage (described by Butler), note that I refer to low intensity stretches, without nerve stress.
- It seems that muscle performance after static stretching is not impaired with short durations of stretch.
- More quality studies are needed because the “stretching world” is still a bit of a mess.
Keys to make it clear: STATIC STRETCHING, OF SHORT DURATIONS AND LOW INTENSITY MIGHT BE HELPFUL in certain sports.
Remember: Things are not white or black, but gray, which makes things complicated and fun.
Sure you’re thinking “well, and what about dynamic stretches?” The answer in a future blog post.
Comments are welcome, either to add something or to tell me how wrong I am.