Back pain and worse hazards of sitting in chairs way too much

The Trouble with Chairs

Back pain and worse hazards of sitting in chairs way too much

by Paul Ingraham, Vancouver, Canada

Sitting too long can cause back pain

This article is of interest for people with minor low back pain who could use some tips on how to cope with spending too much time in chairs. If you are having more serious or chronic back pain, please see the back pain tutorial. If you have a fresh case of back pain that’s kind of freaking you out, start with this one instead: When to Worry About Low Back Pain: And when not to. What’s bark and what’s bite?

Life in chairs is at least a little bit hazardous to your health. We know this today thanks to good science, from sources like British Journal of Sports Medicine (more on this below). But during my decade as a Registered Massage Therapist, I learned of the more obvious, musculoskeletal dangers of chairs just from watching my clients suffer through their desk jobs — it seemed obvious that a lot of time in a chair was likely to cause trouble.

I described The Chair Problem to clients in many ways. I called my excessively sitting clients “chair warriors” who came to me with “chair wounds.” I said things to them like, “Did you get in a fight with a chair?” (So witty!) I told them that sitting in a chair is practically like an Olympic event, and they were elite chair athletes — that they could endure it thanks to regular chair endurance training since kindergarten.

“If you put a caveman in a chair for eight hours a day,” I’d quip, “you’d probably kill him.”

Occasionally, I told the young chair warriors scary stories about the crippled old ones. I saw people at every stage of their chair-o-centric careers, and at every stage of chair-induced disability …

  • twentysomethings just beginning to feel a bit stiff — an annoyance!
  • thirtysomethings living with the constant annoyance of pain and stiffness
  • fortysomethings suffering from an array of mildly debilitating chair-induced injuries
  • fiftysomethings driven from their jobs by serious chair-induced malfunction

I tried to convince the younger ones to protect themselves as early as possible.

And then I became a writer, and soon needed my own advice. Now my butt feels numb half the time. I creak and crackle almost continuously. My neck has a nasty crick three days out of five. My shoulders are hunched forward like they’re being pulled on by teams of oxen. And ominous aches flicker around my body like brush fires.

Chairs are bad news. Sitting a lot is bad news. Why and what can you do? In this article, I’ll review the science and health effects of a sedentary life, but with a focus on the musculoskeletal effects — the aches and pains and stiffness.

The still life: what so bad about sitting, exactly?

In the science fiction classic, Ringworld, Larry Niven paints a future full of frail, sensitive people. Pain and effort are virtually eliminated, and fitness and pain tolerance along with them. But so what? It’s no great loss, as long as no one has to do any physical work or suffer. Right?

What Niven didn’t know then is just how unhealthy it might be to live a life without effort.

We’re already half way to that future. Everything our great grandparents did was more work. The population of agricultural workers is less than a third what it was fifty years ago, let alone a hundred years ago.1 The most trivial tasks required more physical effort then than now, and most things that are hard work have been automated: transportation, agriculture, manufacturing. The Information Age has created legions of workers who literally only lift their fingers for eight hours every day.

It’s not the longevity lifestyle: a national Geographic article examining three unusually long-lived groups of people found that regular activity was a major common denominator, among other things.2 None of them were programmers. We’re certainly soft. Musculoskeletal problems, at least, seem to be steadily on the rise. (That’s hard to prove, but there is evidence.)

The basic problem is that biology is a use-it-or-lose-it business. Everything in the human body works on feedback. Nothing works (or heals) without stimulus. Tissue can literally die without stimulation. A bed sore is a rotting patch of stagnant tissue, and it’s a real and serious problem for anyone who actually can’t move. (This is how Christopher Reeve died in 2004: an infected pressure ulcer.) Simply failing to move isn’t much better.

Chair-bound workers are essentially suffering from sub-clinical bed sores: muscles start to howl for the physical and neurological stimulation they need to survive and thrive, but we only move just enough and just in time to stop tissue from actually starting to become necrotic (dead). But they certainly get “sick,” especially in the shoulders, back and hips — which tend to remain relatively immobile even when we get up and go to the water cooler.

What do we lose?

Everyone knows you’ve got to “use it or lose it,” but what does that mean exactly? What do we lose, and why? And how does using it help?

Research has shown that chronic inactivity causes marked degeneration of virtually every measure of physical fitness,89 such as relatively obvious problems like the degeneration of reflexes,10 interesting examples like reducing the tendon rot from disuse mentioned above, and back! — vulnerability to chronic pain.

Research like this began a long time ago, most of a century — a litany of bad news for chair warriors, connecting inactivity to cardiovascular disease, diabetes, and cancer. Sitting around is even exhausting! True story: you will feel less fatigued if you get regular activity.

There are probably many mechanisms for all this, but one of the most interesting is that muscle tissue may actually be a wellspring of health-sustaining, regulatory chemicals — kind of like big, beefy glands that you can flex — but they do this mainly when they are working, almost like they need pumping. When resting for too long, muscles cells stop producing these substances that we need for normal biological operations.

That’s all pretty grim, but it gets worse: activity may not reverse that effect, or not easily. The effect just described, for instance, was not easily reversed by exercise.

Are you an active couch potato?

I sure am! I exercise a lot, but I sit even more. An active couch potato describes exercisers who sit most of their day (kind of like a weekend warrior, but the emphasis is different). It aptly describes nearly everyone who sits at work but is otherwise active.

Despite our activity, active couch potatoes may have the same health risks as entirely inactive ones.

And not only is there a correlation between inactivity and certain kinds of cancer, but it may not be possible to compensate simply by getting more activity when you’re not in the chair. Studying dozens of cancer studies, Schmid et al found that the cancer risk was the same if the chair time was the same, whether subjects were otherwise active or not. “[The results] indicate that the increased risk of cancer seen in individuals with prolonged time spent sedentary is not explained by the mere absence of physical activity in those persons,” the researchers say.

A 2014 experiment put accelerometer’s on a couple thousand people for a while and then checked their aerobic fitness, finding that a couple of hours of sitting was just as harmful as 20 minutes of exercise was beneficial. Which suggests that it may be difficult to exercise enough to compensate for sitting all day.

This all seems quite bad. Maybe as bad as … smoking?

So you may have heard that “sitting is the new smoking”

Indeed, it’s hard not to hear it. This analogy has been everywhere lately (circa 2011-2014), with no clear single origin. NBC News made it news. Runner’s World ran with it. Science writer Alex Hutchinson covered it well for The Globe & Mail, but the headline (which Alex didn’t write) trumpets the analogy like it’s The Truth, already well-established.

But sitting is like smoking? Really? Isn’t that just a bit hyperbolic?

Well, yes, of course it is — smoking is exceedingly bad for you; it’s hard to believe sitting is anywhere near as dangerous, probably “only a fifth or a sixth as bad as smoking,” specifically (according to the editors of British Journal of Sports Medicine, and somewhat tongue-in-cheek, I think26). Many people seem to have become annoyed by the analogy, and some bright people scoff at it…with good reason.

And it’s just an analogy, which serves to suggest two things:

  1. Like smoking, sitting is something previously thought to be almost completely harmless that may turn out to be harmful. This in itself is quite plausible.
  2. The more recent and much more speculative twist: like smoking, sitting may be harmful even if we are otherwise healthy and active.

If the second bit is true — if — then we would want to reduce the total chair time to nullify its negative effects … not just try to exercise to compensate for it. Maybe in the future people will marvel at how a few generations of people ruined themselves because they didn’t know better than to sit down all day?

Now for the reality check

This whole business always seemed fishy to me. Here’s a little logical bombshell dropped on the hype: if a lot of time stuck in a chair was actually as perilous as smoking, people with serious movement limitations — especially paraplegics and quadraplegics — would be dropping like flies. (They aren’t.) So, clearly sitting cannot be disastrous for general health.

And now there’s (already) good evidence that there is, in fact, no clear association between a lot of sitting and mortality: sitting is probably unhealthy in all kinds of less lethal ways (which is what the rest of this article is about), but it’s not killing anyone — certainly not people who are otherwise doing a decent job of taking care of themselves. Hooray!

So that’s one less thing to be unreasonably concerned about. Which is great. Because if anything actually is “the new smoking,” it’s stress.

Adaptation: You are your stresses, for better or worse

There is a reason that babies all look pretty similar: none of them have been shaped by stress yet. Oh, sure, they have some distinguishing features, but nothing like adults. They are kind of larval looking, all of them.

Much of who you are as an adult is a modified — stress-adapted — version of an original template. Most of who you are and what you are physically capable of is the result of adaptation to stresses and stimuli.

All of biology is organized around adaptive reactions to stimuli: immediate reflex (neurological) responses, nearly immediate hormonal and behavioural responses, tissue change responses. Every response is about improving conditions for the organism. Starting to fall down? The organism reacts to stop it. Regular pounding impact on your legs? Make the bones stronger.

Take away the stresses, and the body steadily stops investing energy in unnecessary adaptations. Adapting is “expensive.” You don’t do it if you don’t have to.

Wolff and Davis, bone and meat

The way some tissue adaptations work has been extremely well-described by science. Others, not so much. Bone adaptation is the best understood … and the most surprisingly fluid. Bone adapts well.

"There are two “laws” of tissue adaptation, one each for hard and soft tissue. Wolff’s law is that bone will change and strengthen in response to loading. This was first noticed by Julius Wolff in the 19th Century, who got the naming rights. It was greatly refined in the mid 20th century by Dr. Harold Frost, an American surgeon who studied bone biology, and published scientific papers more often than I change my socks. The full details of how bone responds to stress are described in his Mechanostat model. The corollary in soft tissue is the obscure and much less developed Davis’ law. (No one even seems to know who Davis was.)

Although there’s no question soft tissue does adapt to stress, the responses of muscles, tendons, and ligaments are much more complex and less well understood. Many treatments are based on the idea of forcing adaptation or “toughening up” tissues by stressing the tissues. It has always been a reasonable idea, but the devil is in the details: what constitutes the “right” amount and kind of stress is difficult to know, and the results of such therapies have generally been highly inconsistent.

One of the best use-it-or-lose it examples: running

In 2012 and 2013, it seems to have become strangely fashionable to deny the health benefits of running, and to assert that it actually makes you fatter and erodes muscle and bone! For example, these claims are actually made in John Kiefer’s popular article, Why Women Should Not Run (and shredded in this great rebuttal, Sorry, but Science Says Running is Good for You, Not Bad).

Running can be hard on bodies, but it takes mental gymnastics and abuse of the evidence to believe that “cardio above a walk or below a sprint is bad for you (especially if you are a woman).” However, even the assumption that running can be “hard on bodies” is not safe. For instance, the evidence actually shows that “running significantly reduced arthritis and hip replacement risk.”

Say whaaat? Running is good for joints?

Well, at least not particularly bad for them. The results are probably due in large part to the fact that runners were typically skinnier. Nevertheless, the data flies in the face of the common assumption that running is much harder on the joints. Instead, what it clearly shows is that running is either neutral or helpful …. probably because using joints is healthier than not using them, on average.

Obviously overuse is another matter.

The Goldilocks Principle: use it or lose it, but not too much

Get more exercise, but don’t go overboard. Although the modern human tends to err on the side of “not enough” exercise, it’s also surprisingly easy to push too hard when you’re unconditioned. “Too much” is surprisingly little for tendons and joints that aren’t used to much. This explains the plague of repetitive strain injuries in weekend warriors

A fascinating 2007 study showed that tendons are harmed by both over and under use. Tenocytes (tendon cells) adapt to the forces imparted on them, creating a tissue tolerance “set point” depending on your activity level. This set point can decrease with disuse, and increase with exercise — as long as there’s enough rest. Activity that is too frequent or intense might damage cells without giving them a chance to adapt. Biological proof of “use it or lose it”!

That pretty clearly implies a need for some kind of in between exercise intensity, something not too easy nor too hard: but a Goldilocks “juuuust right.” To avoid hurting yourself, take only baby steps outside your comfort zone — especially at first, and especially with any activity that’s highly repetitive.

You’re not seizing up (not literally anyway)

There’s a popular notion that sitting causes real shortening of muscle tissue: that you “freeze like that.” Specifically, the idea is that sitting causes your hip flexors to truly shorten, to cinch up and stay that way, to actually lose extensibility. This is not wrong in itself. For instance, a good quality 2012 study found that high heels cause adaptive shortening of the calf musculature by 13%. And here’s an example of the argument being made by a particularly credible and eloquent expert, evolutionary biologist Daniel Lieberman:

Paper after paper, study after study, have shown that chairs give us back problems because they shorten our hip flexors, give us weak backs, of course it make us sedentary. We take years off our lives probably by sitting in chairs, but we like them because they’re comfortable. You go to an African village, you find me a chair with a back. That’s a rare thing out there.

Brains Plus Brawn, by Daniel E Lieberman

Unfortunately, it’s not quite as clear cut as that. Even when muscles do shorten, it doesn’t necessarily mean much. That calf muscle shortening I mentioned above? The authors of that paper also found that it had no measurable effect on ankle function. Todd Hargrove of explained this very well:

It is well known that completely immobilizing a joint for an extended period of time can lead to loss of muscle sarcomeres and contracture and cross linking of connective tissue. However, it appears that one can fully prevent any negative effects of extended immobilization on tissue length with only short and infrequent bouts of movement. In one study, researchers kept the soleus muscle of a rat completely immobilized in a cast for 10 days. Every two days the cast was removed and the muscle was stretched for fifteen minutes. This was enough to preserve tissue length, but not enough to make the rat happy with the experiment.

In another study, just half an hour of stretch a day preserved range of motion in a muscle that was immobilized in a shortened position for the rest of the day. These studies suggest that sitting in a chair almost all day every day would not cause loss of tissue length, provided you get up to go the refrigerator every once in a while.

So it takes an enormous amount of abuse of your body to have any effect on muscle length, it probably doesn’t matter all that much, and it’s really not that hard to prevent. A lot of sitting is almost certainly problematic, … but probably not because of “seizing up.”

Don’t stretch: mobilize!

No — you do not need a stretching habit, per se, to keep your muscles from shrivelling up. Nearly any movement is sufficient to prevent that (see previous section). Although it’s better than nothing, getting out of the chair to stretch specifically is simply the wrong tool for the job. A little static elongation of muscle tissue just does not constitute adequate stimulation to be an antidote for all the effects of four hours of sitting per day, let alone eight or twelve.

What you need is a similar-but-better concept I call “mobilizations”: repeated, rhythmic elongation and contraction of muscle tissue. For instance, when most people get up from a long sit, they will instinctively stretch their arms backwards, opening up the chest, and a few will then close the chest as well, flexing the same muscles they just stretched.

That’s the perfect thing, the right impulse — you just need to do a bit more of it. Repeat! Doing it once pulls your chest and upper back muscles away from the brink. Doing it ten times in a row a few times a day is mobilizing. Basically: light exercise, emphasizing the range of motion of the joints that need it the most after sitting in a chair.

What is it, exactly, that we have to use?

Everything — but, above all, your heart and lungs, and your brains if you want to keep sharp into old age.

The evidence is overwhelming that moderate aerobic activity is probably the single most important kind of exercise … because there isn’t a single cell in your body that doesn’t depend on a constantly blood-borne supply of oxygen and nutrients. The delivery system must be constantly challenged. Aerobic exercise affects the entire system.

But you really have to use anything that you don’t want to lose.

There is a concept in athletics called “training specificity.” It’s one of the Laws of Exercise: you get good at what you do, and only what you do. If you jump up and down on one foot, you’ll get good at jumping up and down on one foot … but not the other foot. If you lift weights slowly, you’ll get good at lifting weights slowly … but not good at lifting them quickly.

You kind of need a specific exercise for anything you want to keep in shape. Which is why so many exercise experts recommend a wide variety of exercises.

Should I get an expensive chair?

The importance of extremely comfy and ergonomically dazzling chairs is generally exaggerated. There is simply no such thing as a perfect chair: your body isn’t comfortable with any position for hours at a time. The problem isn’t the position that your body is in, but the lack of motion and variety of stimulation, and no one chair can really solve that.

Unless it’s quite mobile by design…