Stretching – An Update on the Current Science

Thank You For Listening To Season One – Total Performance with Siobhan Milner

Today is episode four of Siobhan Milner’s minis which are shorter solo episodes where I dive into a particular topic. If you have a topic you want me to dig deeper into then please let me know over on Instagram, or shoot me an email.

In this episode, I am discussing stretching. I’ve had a few people ask: “If stretching doesn’t improve range of motion more than other movement forms, why should I stretch at all?” So here’s a quick update on the science around stretching and its effects on your range of motion, recovery, and injury risk.

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Transcript of Podcast Episode:

An Update On the Science Around Stretching

Siobhan Milner: Today I’m gonna give you a little bit of an update on the science around stretching and what it does and doesn’t do. So recently I’ve had people asking me why they should stretch at all because stretching has not been shown to improve range of motion more than any other movement forms. So why should we be stretching?

And I know for some people that’s also probably news. So I’m gonna get into a little bit of an update around the science there. So there was a 2021 systematic review and I’ve got some, uh, links to this on my blog that was comparing strength training to stretching, and it found that there were no differences in their effect on the range of motion.

I think here it might be worth me explaining what a systematic review is as well, just in case anyone’s listing doesn’t have a background in it. So a systematic review is a type of research study that looks at all of the available literature on one topic with the goal of summarizing and synthesizing the evidence.

So sometimes you might hear people say things like, oh, well, you can find any study that says what you want it to say, but if we look at a systematic review, we’re gonna see what the overall data says in terms of that topic right now. So it’s much more trustworthy than a single study. So once all of the studies have been identified and evaluated, researchers analyze the results and then they make conclusions about the overall state of evidence on the topic.

Systematic reviews are considered to be one of the highest forms of evidence because they are based on a rigorous and transparent process to identify and evaluate all relevant studies. So a meta-analysis just goes a little bit further. It’s a type of a systematic review that goes one step further by combining the results of multiple studies into a single quantitative.

So quantitative means we’re running the numbers, really. So the goal of a meta-analysis is to provide a more precise estimate of the effect of a particular intervention. So in this case, stretching. So providing a more precise estimate of the effect of stretching by pulling the results of multiple studies.

We talk about something called the hierarchy of evidence, which is a way of ranking different types of research based on how reliable, and invalid they are. So this is usually shown as a pyramid with the highest quality studies at the top and the lowest quality studies at the bottom. So a systematic review and meta-analysis, they’re generally considered to be at the top of the pyramid, so they’re the highest quality studies.

And then what follows would be randomized control trials, then cohort studies, then case-controlled and cross-sectional, then case reports and case series. And uh, if we thought about something like anecdote, it would be even below. So it’s really our most trustworthy form of research. So back to the systematic review from 2021.

It found that comparing strengths, and training to stretch, there was no difference in the effect on the range of motion. These researchers did a follow-up paper, and it’s a really cool paper actually. It’s called Can I versus Do I have to? So this is Alfonso etal. I just think they do a really good job of making this really clear.

So I highly recommend looking this paper up. So it’s called Time to Move from Mandatory Stretching. We need to differentiate, can I from, do I have to by Alfonso Etal 2021? But I will tell you a little bit about what’s in there. So in terms of comparing strength training to stretching for improving our range of motion, they.

Can I stretch to improve my range of motion? Yes, but do I have to stretch to improve my range of motion? Possibly not, but more comparative research is required, and sports requiring an extreme range of motion should be considered separately. So I’m gonna come back to that, but that’s worth it. That’s a worthwhile thing to keep in mind, especially if you’re in something like dance or a circus, or something that requires an extreme range of motion.

But of course, the other thing that we were told for many years was that we needed to stretch to aid recovery, both a Cochran review, which again is, it’s a type of systematic review. Um, they’re very well-known, systematic reviews as well. They’re also updated, so they really keep an eye on the literature. So there was a Cochran review that looked at stretching to prevent or reduce muscle soreness after exercise.

And then also the systematic review and meta-analysis that I mentioned before by Alfonzo are these two different systematic reviews, they found that there was no evidence to support stretching, to aid recovery, or lessen delayed onset muscle soreness. So it doesn’t reduce soreness in any clinically important way.

So not in a meaningful enough way that it would be impactful for us. We wouldn’t. So stretching doesn’t improve the range of motion more than strength training. There isn’t any evidence to support stretching, to aid recovery, or lessen muscle soreness. So what about injury risk? This is another thing you’ve heard people probably say stretching could reduce injury risk.

So again, from Alfonzo Atal’s systematic review, they said the answer to, can I stretch? Yes. It will probably not increase injury risk, but the answer to do I have to stretch in terms of decreasing injury risk is possibly no as the likelihood of decreasing the injury risk is contentious. So now we are hearing that stretching doesn’t really improve our range of motion more than anything else.

It doesn’t reduce muscle soreness after exercise. It doesn’t improve recovery, and it doesn’t decrease injury. So why would we stretch at all what I would say we know from pain science? And again, I’ve got a great episode with Arthur, my first-ever podcast episode. If you wanna learn a bit more about pain science, we know from pain science that any movement makes bodies feel better and can help reduce pain.

So if stretching is gonna be what gets you moving, It’s still good for you. Arguably, other modes of movement could be more productive if we consider the need to maintain strength in muscle masses. We age or improve cardiorespiratory fitness and metabolic health, but movement in and of itself is beneficial in so many ways.

So even though there isn’t research proving that stretching reduces soreness or that it meaningfully contributes to injury prevention, all of the caveats and the research say stretching probably doesn’t increase range of motion more than any other kind of. But this assertion may not stand for activities that require super physiological ranges of motion.

So this is what I said earlier. If your sport requires more range of motion than is normal, you are probably gonna need to work towards getting that range of motion. So if we think of something like completing the splits, we could say to you like, oh yeah, you could just do strength training, but there aren’t really very many strength training exercises that end up with you in the split.

So if you wanna be able to get into the splits, you’ve gotta practice getting into the splits as well. If your sport really requires you to be in end-range stretching, then you’ve got to stretch, use it or lose it. As true for many aspects of physiology. And if you wanna get into some extreme ranges of emotion, you’ve gotta practice getting there safely.

And while still working on strength to support your joints, it’s important to know that being strong is still really important, even while you are working on flexibility. So do you need to stretch to be healthy? Probably not. You could probably go your whole life without stretching, but you still want to be moving in the ranges of motion that you need for activities of daily living and moving into different positions than normal.

Because in general, our bodies like consistency but also variety. They’re kind of tricky beasts like that, but there’s nothing wrong with stretching safely if it feels good for you. So what I mean by safely is to make sure that whenever you’re stretching, it feels like a relatively gentle stretch. I’ve worked with a lot of dancers who have come to me with overstretching injuries because they haven’t taken a progressive overload approach to stretching.

Again, I’ve got a little. Zone on progressive overload, if you wanna learn a bit more about that. But in general, our bodies adapt really well to load, but we’ve got a progressively increasing load. So if you decide, oh, I wanna be able to do the splits and you’ve never done them, and you try and force yourself into the splits, yes, you’re likely to hurt yourself.

Whereas if over time you slowly work towards that and you’re also doing some other things to support your mobility and range of motion around the hips, for example, then it’s more likely that you’re gonna accomplish. Safely without hurting yourself. So some of the reasons in the ways I use stretching, and I do still use stretching.

I often use it for cooldowns. Even though like I say, it’s not actually reducing our muscle soreness, it’s not actually preventing injury risk. I use it a lot for the mental aspect because for many people, stretching just feels good. It helps ’em calm down after a training session. So I see no reason not to stretch.

And like I say, it’s not that stretching doesn’t improve the range of motion at all. That’s not true. It’s just that it doesn’t improve the range of motion more than strength training. For example, if we were doing a lot of the general generic stretches, so it still improves a range of motion, so it’s still a tool in the toolbox to have.

I also work with a lot of dancers who require more extreme ranges of motion. So for them, I will use a combination of lots of different types of stretching. Static active dynamic. And we’ll also use some other things like Neurodynamics and Proprioceptive Neuromuscular Facilitation. And the other thing is we know that regulating breathing plays a key role in recovery processes.

So I like to use gentle stretching as an opportunity to incorporate breath work, especially with some athletes who might otherwise be a little bit weary of incorporating breath work cuz it feels a little bit woo-woo. So that’s just a little bit of an overview. Like I say, I’ve got, um, some posts on my website with some links to these.

Studies as well. If you’ve got any questions about stretching or the current state of the science, please feel free to send me an email or drop me a comment on social.