Feel stiff? Tight? Think your range of motion isn’t what it should be? These things often go together, but they don’t always, and they definitely aren’t the same things. Wrapping your head around the difference is good human body owner’s manual stuff. Feelings of stiffness and tightness are usually a symptom of something at least a little bit wrong — a kind of mild pain.
Body is not stiff, mind is stiff.
K. Pattabhi Jois
How far can you go? ROM is the only obviously objective fact about flexibility we have to work with. You can measure it with a protractor.1 A limited ROM can be confirmed in joint that actually cannot move as far as it “should” be able to move.
Which is how far, exactly? Human averages are almost meaningless, because the range of natural variation is generally large.2 A better measurement might be how much you want or need a joint to move — for instance, gymnasts obviously need ROM more than accountants do. However, a desired or perceived need for ROM is a good standard either, because so many people assume that their range is worse or more “abnormal” than it actually is, and because they assume that more range is better than it is. It’s not that great. Doing the splits is not especially useful.
Many people have trivially and naturally limited range of motion, especially men in their hamstrings. He seemed flexible, but it was all in how he used what little range of motion he had. Just as cats naturally have extremely extensible muscle tissue — about 100% stretchier than human muscle tissue! — the average human male has relatively rigid hamstrings. They just aren’t very stretchy. They doesn’t necessarily hold him back in any way — it may not be causing any problems — he just can’t touch his toes! And yet many men bemoan their lack of flexibility.
The martial arts seem to demand flexibility, and of course it can be powerful asset, but even there it’s not necessarily so. The most memorable martial artist I ever worked with — a formidable, grizzled old practitioner of Aikido — was also one of the least flexible.3
Only you can say that you’re stiff. “Stiff” and “tight” are imprecise symptoms and sensations, completely subjective, and unrelated anything that can be objectively measured, like range of motion. No instrument can measure stiffness.
Stiffness is an unpleasant sensation. It feels like something is wrong. No ever feels comfortably stiff.
A short but healthy range of motion is probably not the cause of any wrong-feeling stiffness. If your ROM is limited by natural biological variation, pushing at the end of the range is a neutral sensation — it doesn’t feel like there’s a problem, and therefore it is not “stiff.” It’s more just a sensation of being stopped, or of pulling too hard. If there’s nothing actually wrong, they probably won’t really feel “tight” or “stiff” unless you are trying too hard to stretch them.
The feeling of wrongness leads to an understandable assumption that to feel stiff is to be stiff — that is, feeling “stiff” and/or tight is the same thing as having a limited ROM. But it’s not necessarily so. People with normal range, or even good range, can feel stiff and tight! And people with lousy range can actually feel perfectly fine.
Most importantly, stiffness mostly occurs without even coming close to testing the limits of your range of motion. You can easily feel stiff when you stand up from a chair: an easy action that isn’t even remotely limited by poor ROM. What’s uncomfortable is movement, contraction, and tension on anatomical structures well within the normal ROM.
“I feel really stiff — it’s nice!”
no one ever
There are so many possibilities, ranging from undiagnosed pathology to the purely psychological. If you feel limited emotionally, you may feel that way in the flesh too.4 Trying to diagnose stiffness is only a hair less baffling than trying to diagnose the cause of a “funny feeling.”
There are a couple some familiar circumstances where we obviously get stiff temporarily: the early stages of cold or flu, and the soreness that follow relatively big bout of exercise (delayed onset muscle soreness (DOMS)). Both of these involve some form of widespread inflammation, and often also actually feel painful. From these obvious experiences of acute stifness, we can infer that stiffness must have something to do with relatively widespread mild tissue irritation (although you can certainly also just be stiff in a specific area, like the back).
Why would we have tissue irritation without an obvious source like DOMS or infection? Chronic mild to moderate tissue inflammation has many possible causes, and is probably more prevalent and persistent than most professionals realize.5 But by far the most familiar source of inflammation — and stiffness — is aging. Everyone gets more inflamed as they age — known as “inflammaging” — and it happens to some people sooner and worse than others,6 like arthritis (which may itself just be one of the effects of the inflammation).
Some tissues, when irritated, probably create stronger sensations of stiffness, and a prime candidate here is muscle. But why would muscle get irritated, other than a big workout? For younger people who feel stiff, and can’t just blame “inflammaging,” there is one major suspect: the ubiquitous phenomenon of “muscle knots,” technically called trigger points. These patches of soft-tissue that are sensitive to touch for no apparent reason are extremely common, and the pain is the tip of a bio-berg: for every spot that actually hurts (and “active” trigger point), there’s usually more that are just mildly uncomfortable (“latent”). There’s a sort of diffuse halo of stiffness and tightness around trigger points.
It’s unknown whether trigger points are a phenomenon of literal muscular tightness — actual contraction, or resisting elongation. They may be, and the dominant theory says so. On the other hand, the dominant theory is old and controversial,7 and trigger points could be pure neurology and sensation.8 So trigger-pointy tissues may actually resist stretch, or their extensibility may be unaffected,9 but they will feel stiff either way.
Another clue that the feeling of stiffness isn’t really about ROM is that it can so easily occur even when muscle isn’t even being stretched. For people who feel very stiff, this is unpleasantly obvious: it is apparent with even the slightest movement, or even just pressure. No stretch required! When you feel stiff and uncomfortable from sitting down for too long, you are feeling your trigger points. When you shift, or stand up, and feel extremely stiff and tight, obviously it’s not because you are challenging the limits of your joints’ ranges of motion! Rather, you are stimulating soft tissues that contain trigger points that are mildly irritated even by normal movement.
This is even more obvious when you have major post-exercise muscle soreness. There is clearly nothing wrong with your flexibility. In that state, you can stretch just as far as normal — it will just hurt more. Everything hurts more! All stimulation of your muscles is uncomfortable (stretch, pressure, vibration, anything). And yet people say, “I’m so stiff today!” Translation: “Moving hurts today!”
Think twice the next time you think that you need to “work on your range of motion” because your feel stiff and tight. In many cases, what you may need is some relief from trigger points instead — your ROM is beside the point!
I am a science writer, former massage therapist, and I was the assistant editor at ScienceBasedMedicine.org for several years. I have had my share of injuries and pain challenges as a runner and ultimate player. My wife and I live in downtown Vancouver, Canada. See my full bio and qualifications, or my blog, Writerly. You might run into me on Facebook or Twitter.
For more information about trigger points, see my ebook Trigger Points & Myofascial Pain Syndrome or free articles like my popular Perfect Spots series. For more about why stretching is over-rated, and why most people stretch for the wrong reasons, see Quite a Stretch — which is always good for starting an argument. And the two topics merge in Stretching for Trigger Points, which is an excerpt from an even more ridiculously detailed section of my book.
Some other related articles…
— Several miscellaneous improvements, especially new information about the role of inflammation and “inflammaging.”
— Minor update. Added a neat footnote and citation about the trouble with “average” ranges of motion. Plus miscellaneous editing.
An informal survey of the poor state of trigger point science from an articulate expert, Fred Wolfe, a rheumatologist. Dr. Wolfe gives his first-hand account of the first trigger point diagnosis reliability study in 1992 (see Wolfe), and he tells the story of meeting Dr. Janet Travell and observing her unscientific conduct with a patient.BACK TO TEXT
Quintner and Cohen’s 1994 paper is a historically significant critique of the “traditional” (Travell & Simons) explanation for the phenomenon of trigger points, known today as the “integrated hypothesis.” They propose that peripheral nerve pain is a better explanation. More specifically, they proposed that irritated or injured peripheral nerve trunks may be the cause of pain, rather than lesions in muscle tissue. This hypothesis has advantages and problems, just like the idea it is intended to replace. Its main problem is that there’s no obvious plausible mechanism for ubiquitous nerve irritation. I review the hypothesis more thoroughly in my book, Trigger Points & Myofascial Pain Syndrome.
An updated version of this paper was published in 2015 in Rheumatology (Oxford).BACK TO TEXT