Stretching: Good or Bad?

A few weeks ago, whilst lunching with Sensei Hutch, he mentioned reading an article on stretching being worthless--or worse--which contradicted all he'd believed about stretching for so many years. This article surprised me since I'd seen lots of pro-stretching articles over the past year or so. Plus the rise of dedicated stretching centers where you can go to be stretched by a "licensed coach." Some other practices, such as massage therapists, have also jumped on the stretching bandwagon.

Recently I read another pro-stretching article and thought: why all the confusion? So let's take a look...

I'll be using the two articles mentioned above as references. There are plenty of other examples for each perspective but these will do nicely. Here are links to each...it's easy to tell which is which by the titles:

https://www.outsideonline.com/2408467/case-against-stretching-flexibility-research

https://www.forbes.com/sites/nomanazish/2020/03/31/why-you-should-do-stretches-every-day-and-the-right-way-to-do-it/

What is "Stretching"?

"Flexibility" refers to the ability of a muscle to temporarily stretch when needed. Note the word "stretch" in there. The most common test for this has long been the sit-and-reach test which is supposed to measure the flexibility of the hamstrings and lower back.

Stretching and flexibility are the focus of both articles under review.

Over the last twenty years or so, there's been a greater emphasis on "mobility" which refers to the ability of a joint to actively move through its full range of motion (ROM). So flexibility and mobility are related but are not the same thing.

As an example, consider bending over to touch your toes (without bending your knees). An inability to reach your toes is generally considered indicative of a lack of flexibility. But if you lay on your back and have someone raise your straight leg, you may demonstrate normal flexibility. How can this be?

When standing and reaching for your toes, the position of the hips is a major factor. If they tilt, or push back, the anchor point for the hamstrings moves back which means they need to stretch more for you to reach your toes. The hamstrings might also be engaged due to weak stabilizer muscles which would make them less flexible.

Stretching = Bad

With that in mind, let's start with the anti-stretching article.

First, let me say I agree with most of what he writes, although describing it as "stretching is useless" is hyperbolic.

Science doesn't support commonly-cited stretching benefits such as reduced injuries, reduced soreness, or reduced risk of falling with age. This wasn't always the case: studies from the 60s and 70s did show benefits from increased flexibility. But with more and better studies, things changed.

Part of the article is, however, rather disingenuous. It refers to the 2018 edition of the Physical Activity Guidelines for Americans from the Department of Health and Human Services. He cites it as follows:

The Guidelines state repeatedly that “flexibility activities are an appropriate part of a physical activity program, even though their health benefits are unknown and it is unclear whether they reduce risk of injury.” Um... then why are we recommending them?

However, he leaves out this part preceding the quote from Guidelines:

Some types of physical activity, such as ballet or salsa dancing, require more flexibility than others. Flexibility activities enhance the ability of a joint to move through the full range of motion. Stretching exercises are effective in increasing flexibility, and thereby can allow people to more easily do activities that require greater flexibility.

U.S. Department of Health and Human Services. Physical Activity Guidelines for Americans, 2nd edition. Washington, DC: U.S. Department of Health and Human Services; 2018.

Using the word "flexibility" instead of "mobility" makes it more sensible but the intention is clear. It's also important to note that Guidelines refers to "activities" rather than athletic endeavors; i.e. it's generic. The anti-stretching article is primarily focused on athletics.

Another quibble with the article:

And finally, being flexible doesn’t improve your sports performance—unless you’re doing something where range of motion has a direct impact. If you’re a gymnast or a ballerina or a hockey goaltender, you’d better be flexible. Even as a cyclist, you need enough flexibility to be able to get into an aerodynamic riding position and still pedal comfortably. If you’re a runner, on the other hand...

So there's a list of sports activities in which flexibility matters (add martial arts to the list) but it doesn't apply to running. Got it.

The article sums up the case against stretching with this:

So anointing flexibility as one of the five “major components” of physical fitness gives it undeserved importance, and leads people (including, apparently, personal trainers) to spend time that could otherwise be devoted to other activities with far better return on investment.

This is a bit dramatic. For one thing, it implies a fixed amount of time for training which is, of course, a given. (At most, it's 24 hours a day.) But we could then go down a slippery slope and argue that strength training is more worthwhile than speed training (one of the five "major components") so skip the latter. And squats are more beneficial than bench press so if you only have so much time... You see where that goes.

The thing is, stretching is a much different activity than the others. For most people, it's relaxing. As such, it can be done separately from a "workout." Or it can be used during rest periods during training. (When wapping, we use "pick your favorite stretch" for recovery from some of the hardest rounds.) It's not necessarily a question of "time that could otherwise be devoted..." It may well be additional time.

Despite these points, I still agree with much of the article and will explain further in the conclusion. One thing I'd add is that saying stretching is unnecessary is hardly a new idea.

Probably the most heretical remark to make about stretching is to suggest that the dedicated usee of stretching sessions may not even be necessary, especially since many athletes dispense entirely with special stretching or even warm-up sessions before [or] after training without suffering injury in training or competition.
...
One can use the actual movements from a sport to serve as a highly adequate and effective way of preparing the body for subsequent work.

"Supertraining" [Verkhoshansky, Siff] 2009

Note that the sixth edition was from 2009. The book was originally published in 1993.

Stretching = Good

The pro-stretching article is easier to comment on because it's mostly fluff. (Probably not surprising since it's a fitness article from Forbes.) I just picked it out of my feed because it was convenient but really it's quite typical of pro-stretching pieces in that it makes unsubstantiated assumptions.

It starts with this:

Stretching is a key component of any well-rounded exercise routine.

The anti-stretching article would disagree and cited studies to support its conclusion. This one just says it as if it must be true. It's a big time-saver for the writer!

It then goes on to quote a CrossFit "fitness expert" who makes more unsubstantiated claims. Then a "celebrity fitness coach" who offers this gem:

"When you stretch, you're improving blood flow in the body and, in turn, circulating more nutrients throughout the body..."

Is she circulating more nutrients?

Awesome! You know what else does that? Walking. Playing piano. Falling down stairs. (Not recommended, but it would increase circulation, at least temporarily.) Pretty much any movement. Or maybe he means enhanced flexibility from stretching provides improved blood flow all the time. That makes no sense, but reference some reputable studies and I'll gladly reconsider.

Next up, it finally links to some sources. The first is for this statement:

A lack of stretching can limit your range of motion over time and make your muscles tight and shortened due to inflexibility.

Unfortunately, it links to this:

https://health.ucdavis.edu/sportsmedicine/resources/flexibility_descriprion.html

It's from UC Davis so it must be well-sourced, right? Nope. It actually trots out more unsubstantiated claims than the pro-stretching article and cites nothing. It doesn't even list an author. Maybe because it's embarrassingly bad. It's not a good sign that the link even has a typo in it.

Next line:

This consequently makes your muscles weak, increasing the risk for strains, joint pain and muscle damage.

It links to this:

https://www.health.harvard.edu/staying-healthy/the-importance-of-stretching

Hey, at least there are no typos in the link. And it's from Harvard so it must be good, right? Nope. More of the same. Plus it features some golden gems like this:

Stretching keeps the muscles flexible, strong, and healthy...

Regular stretching keeps muscles long, lean, and flexible, and this means that exertion "won't put too much force on the muscle itself"...

Wow...stretching makes muscles strong and lean? Who knew? And it's not at all clear how flexibility would affect the force put on a muscle. Explain that one, Harvard!

The pro-stretching article goes on to some dos-and-don'ts for stretching and some example stretches, but that's the "how" part of the article and we're only interested in the "why" for now.

It's not a good article but, as mentioned, is pretty typical of the pro-stretching mindset. Stretching is good because ... everyone knows it is!

Oh...I was almost done with this post when another pro-stretching article popped into my feed:

It's more of the evidence-free pandering that we'd expect but goes the extra mile with one I hadn't seen before: "...engaging in prolonged stretching exercises can help reduce cholesterol in the body." Hooray!

To be fair, it precedes that statement with "Paired with a healthy diet," but then a healthy diet can help reduce cholesterol levels on its own. What evidence suggests stretching has any additional effect? None that I know of. It links "reduce cholesterol" not to any study but to a generic "lower your cholesterol" page that doesn't mention stretching at all (unless you include it under "Stay active").

I'd better stop there before another evidence-free pro-stretching article shows up in my feed!

Stretching Not Stretching

It's important to note that both articles are primarily about static stretching which involves getting a muscle into a stretched position and holding it there. This is what most people think of as "stretching."

Gary doing side knees
An example of dynamic stretching

Both articles also mention dynamic stretching which involves movements taken slightly beyond the comfortable ROM (range of motion...remember?) with the goal of increasing it.

The anti-stretching article is really anti-static stretching. The pro-stretching article's stretching examples are all static stretches.

Many argue that strength training through a full ROM is sufficient stretching. Some examples:

https://www.vice.com/en_us/article/ywky87/how-to-be-more-flexible-without-stretching

https://journals.lww.com/nsca-jscr/Fulltext/2011/12000/Resistance_Training_vs__Static_Stretching__Effects.22.aspx

http://www.yorkvillephysiotherapy.com/video-blog/pub:39/Flexibility-workout-Stretching-vs-Strength-Trainin

(That last link includes several references at the bottom.)

The anti-stretching article is all over this one:

... strength training is an ideal alternative [to stretching]. Sure, it makes you strong and has all sorts of other long-term health benefits—but if you use your full range of motion while doing it, it can also make you more flexible, with various studies showing increases in sit-and-reach scores of between 10 and 25 percent. Aerobic exercise and other forms of functional and combined training can also boost flexibility, according to a few studies. Basically, it appears that being healthy and active is enough to maintain a reasonable level of flexibility.

Mostly...yes! I'm a big advocate of full ROM in strength exercises. (Ask Sensei Hutch...he'll tell you.) And the best way to stretch for heavy lifting is to start with lighter sets, using those to increase your ROM. It's the last line of that quote I have a problem with: what is "a reasonable level of flexibility"?

One other caveat is that strength training (e.g. lifting weights) can lead to soreness that temporarily reduces pain-free ROM. In this case, stretching can help ameliorate the problem and generally just feels good.

Gary Sez

The flexibility one needs depends on the individual. As mentioned elsewhere, various activities require different levels and kinds of flexibility: gymnast, hockey goalie, martial artist, ballroom dancer, swimmer, etc.

But everyday life involves flexibility too. Scratching your back, picking a piece of paper up off the floor, tying your shoes, sitting on your heels...flexibility makes life easier. In the end, even anti-stretching guy says so:

I can’t deny that, as the parent of a couple of young kids, I kind of wish I could sit cross-legged on the floor more comfortably.

Moreover, for many people stretching just feels good.

So is stretching useless? No! Should you replace strength or aerobic training time with stretching? Probably not, unless you need it for your activity. Fortunately, we rarely have to make that choice since stretching can easily be done during non-exercise time.

As the anti-stretching guy says, don't stretch "because you imagine it will prolong your life, protect you from injury, or boost your athletic performance." Stretch because it feels good and the added flexibility will make your life easier.

Be seeing you.

-gary

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One Comment

  1. Fine article and since my needs require a greater range of motion than most. I will continue to stretch with the added knowledge it is not a cure all for that which ails most athletic folk.

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