You can read read a short summary of this work on my earlier post on “Walking, Vision and Self Awareness”.

You can download the entire paper from my CV page.

ATHLETE Standing to full Height at the D-RATS 2010 Field Test

Sitting All Day: Worse For You Than You Might Think

Starting with a great video to motivate a little motion while at the desk, this NPR article made me happy from the start. But then it got into the science of sitting, and it got a little darker. Steven Blair, a professor of public health at the University of South Carolina recently headed a study that looked at adult men and their risk of dying from heart disease. He calculated how much time the men spent sitting — in their cars, at their desks, in front of the TV and concludes that: “those who were sitting more were substantially more likely to die.” Wow. More sitting equals more risk of death. And not just sitting in a chair – a significant amount of sedentary time was from being in cars. After reading all that, I watched the video for a second time looking for tips on how to get our of my chair more.

Specifically, Steven found that men who reported more than 23 hours a week of sedentary activity had a 64 percent greater risk of dying from heart disease than those who reported less than 11 hours a week of sedentary activity. To put that in perspective, if you spend your day working at a computer you are likely logging 40 or more hours of sedentary time just at your job.  Now add in time sitting and eating, sitting while driving a car, and sitting using a computer or watching TV at home.  Most of us are sitting for 2 or 3 times the number of hours shown to be higher risk!

The article also includes ideas from Dr. Toni Yancey, a professor in the health services department and co-director of the Kaiser Permanente Center for Health Equity at the University of California, Los Angeles, who puts it in simple terms: “We just aren’t really structured to be sitting for such long periods of time, and when we do that, our body just kind of goes into shutdown.”  We’ll see in the next two articles even more data on this!

Is Your Office Chair Killing You?

Reading about the association between sitting and an increased likelihood of death from heart attacks gets my attention.   But any one study can conclude anything, so it is eye-opening to read this in-depth article from Men’s Health which references more studies showing a similar increase in heart attacks among those who spend more time sitting.  It even appears that studies have been coming to the same conclusion since 1953, when British researchers found that (sitting) bus drivers were twice as likely to die of heart attacks as (standing) trolley operators.  What I find surprising is that:

“The amount of time you exercise and the amount of time you spend on your butt are completely separate factors for heart-disease risk. New evidence suggests, in fact, that the more hours a day you sit, the greater your likelihood of dying an earlier death regardless of how much you exercise or how lean you are.”

This appears to be largely driven by chemical changes in our muscles when they are active or inactive.  The largest muscles in our body are in our legs and glutes and they “turn off” when we are sitting and can be activated simply by spending more time standing and moving around (read the article for more details).  This is great news, since it means that we don’t need to spend 3 hours a day at the gym to be healthy, rather we just need to restructure our lives to spend more time on our feet – which we can even do while working. Like elsewhere they mention standing while on the phone, and I would add that a standing desk is probably one of the best tools for spending more time out of your chair (I intend to write in depth about sit-stand desks next – for now see my introduction on the right side-bar of this page).

This article also was a joy to read because it directly echoed and confirmed many of the ideas I’ve written about, such as how your body and fascia adapt to the sitting posture and how sitting makes one more prone to injury when doing basic things like walking.  I really like the interpretation they put on aging:

“Older folks have a harder time moving around than younger people do,” says Hartman. “That’s not simply because of age; it’s because what you do consistently from day to day manifests itself over time, for both good and bad.”

In other words, if we want to be limber and able to move with ease when we are older, we need to keep moving and using our bodies today (and every day!).  I believe that many (but not all) of the aches and pains commonly associated with aging are avoidable through a love of motion and a constant effort to learn how to move and maintain engaged alignment.  I’ll let you know how that theory works when I’m 90. <Grin>

If heart attacks, back pain, and inflexible, fragile bodies aren’t enough, this article also mentions a study that ties the sedentary lifestyle to increased risk for Diabetes: “A 2010 study in the Journal of Applied Physiology found that when healthy men limited their number of footsteps by 85 percent for 2 weeks, they experienced a 17 percent decrease in insulin sensitivity, raising their diabetes risk.”  For even more information on that risk, we turn to yet another article on the risks of sitting, this time from The New York Times.

Is Sitting a Lethal Activity?

This New York Times article covers even more studies on sitting and inactivity (There seem to be many!)   Concerning diabetes they say the following:

“This is your body on chairs: Electrical activity in the muscles drops — “the muscles go as silent as those of a dead horse,” Hamilton says — leading to a cascade of harmful metabolic effects. Your calorie-burning rate immediately plunges to about one per minute, a third of what it would be if you got up and walked. Insulin effectiveness drops within a single day, and the risk of developing Type 2 diabetes rises. So does the risk of being obese. The enzymes responsible for breaking down lipids and triglycerides — for “vacuuming up fat out of the bloodstream,” as Hamilton puts it — plunge, which in turn causes the levels of good (HDL) cholesterol to fall.”

All that from sitting!  The key point is that these effects occur as a result of the muscle becoming inactive.  The solution does not require heavy exercise – merely by standing up we demand action from our muscles.  Another researcher, Dr. Levine, rigorously measures the impacts of inactivity with special pairs of shorts he covered with accelerometers and inclinometers.  He uses these to record every motion of the subject wearing them and tracking how much energy they consume throughout the day.  This approach is much more accurate than self reported “amounts of exercise.”  Dr. Levin then ran a study where he controlled the food and calories that the subjects ate each day, did not allow them to “exercise,” and then raised the total number of calories and tried to figure out why some subjects gained weight and others did not.  The result was that those who gained weight simply moved less during the day while those who did not gain weight responded to the increased calories by moving more – fidgeting, standing up more, walking quickly, using the stairs, etc.  We all know the math: output energy must equal input energy, or we store the extra energy as fat.  The key insight here is that a daylong habit of simple motion has a more significant impact on our total energy consumption than 40 minutes of hard exercise.

Luckily, this conclusion also means that a healthy life doesn’t require a gym membership — getting out of our chairs, using a sit-stand desk, biking to work, walking more, or simply engaging our muscles through techniques like Active Sitting, can help!  There is even a double payback for all this motion – our emotional self frees up and finds joy in motion!  (See “The Joy of Integrated Motion”)  As Dr. Levine says: “Go into cubeland in a tightly controlled corporate environment and you immediately sense that there is a malaise about being tied behind a computer screen seated all day.  The soul of the nation is sapped, and now it’s time for the soul of the nation to rise.”

Free yourself from sitting!! Dance, Walk, Run, Play – Move, Move, Move!  There, in the freedom of motion you will find deep joy and love for life.

Support Causes Atrophy

My biggest concern with much of the design and marketing around ergonomics equipment is the short-term focus on supporting your body in ways that will lead to further atrophy and weakness.  A disturbingly common approach is to proudly announce how ergonomic chairs will protect your health through “anti-gravity support.”  While it sounds initially compelling that your tired sore back needs more support, this approach can lead to a dangerous downward spiral of further atrophy and dependence on support.  Have you ever seen an astronaut after they return from a long stay in space?  They do not stride out of their space ship boldly like Buck Rogers – rather they are often assisted straight into a wheel chair. (See Figure 1) Without the need to counter-act gravity on a daily basis, their bodies have efficiently reduced muscle bulk to save energy and they are unable to stand up safely after landing.  This occurs despite significant time and effort spent exercising while in orbit, as discussed on this NASA webpage:

Exercise is the number one health priority in space, said Don Hagan, director of exercise physiology at Johnson Space Center. “No other activity except eating and sleeping is given that much priority. Two and a half hours each day are devoted to fitness.”

Why is it so important for astronauts to exercise while they’re in space? If astronauts don’t exercise, their bodies start losing bone and muscle. Bone and muscle loss mean decreased size and strength, and can reduce an astronaut’s ability to do work because it makes them weak.

Weakened astronauts would be less able to do tasks while in space, Hagan says. Also, if there were an emergency, the astronauts would need to be in good shape to get out of the Space Shuttle or Space Station quickly. Once they land on Earth, weakened muscles and bones would make walking difficult.

Gravity is your friend – it keeps you strong! If you remove the requirement to exert yourself and engage your body by using supports such as back rests, your body will naturally adapt and become weaker. Instead of following this downward spiral of weakness we can practice Active Sitting where we learn to engage and move our muscles while sitting.  To do this in a healthy manner we will need to address Alignment, Motion, and Physical Conditioning.

Back Rests and Alignment

The first alignment principle to understand is that the tilt of your pelvis has a direct impact on the curvature of your spine.  If your pelvis is in an upright neutral position, it is very easy for your spine to hold itself upright – this is how we have evolved to move through the world.  On the other hand, if your pelvis is tilted backwards, then your spine must curve strongly to keep your back upright and your head up (Figure 2).  This takes effort and will exhaust you quickly.

Figure 2. (A) It is easiest for the spine to support the upper body when the pelvis is in a neutral upright position. When the pelvis is tilted forward (B) the lower back strains to keep the body from collapsing forward. We often unconsciously reduce the strain by using external support, such as leaning on our elbows. (C) When the pelvis is tilted backwards we need to engage our core, like holding a sit-up, to keep from falling over backwards. Since this is tiring, we often use backrests to stay upright, causing our bodies to weaken.

Sadly, many chairs, even “ergonomic” ones, are designed such that your pelvis tilts backwards and throws your back into the backrest.  Chairs that naturally tilt backwards further exacerbate this tendency.  Granted, these chairs feel comfortable because they naturally force you to depend upon the support of the backrest, and that is relaxing.  But, as discussed above, such dependence upon support will lead to atrophy and deeper dependence.

You want a chair that naturally holds your pelvis in a neutral upright position and makes it easy to hold your spine up.  This will make it easier to sit up without continual use of the backrest, enabling your back to stay active and strong.  In fact, a backrest should be exactly what its name implies – a tool used to rest your back when it is tired, not something that you use continually the entire time you are sitting.   So, when you are looking at a new chair, look to see that the seat pan is flat and does not cause your pelvis to tip forward or backwards.

Likewise, if a chair is too low and your knees end up higher than your hips, it will be very hard to sit without back support.   Thus, you want a chair where your knees are even with, or lower than, your hips.  Some chairs have sculpted seat-pans which combine a flat section for the pelvis and formed areas for the legs making it easier for the knees to be slightly lower than the hips without the chair cutting into the back of the legs.  This is a good design feature, but has to be properly fit to your body size.

Figure 3 An example of slouched sitting. Notice the rounded back and thrust forward head. Dont sit like this.

Buying the right chair is only part of the solution.  A good chair will make it easy for you to sit with good alignment, but you can have poor alignment while sitting in the best chair.  Good alignment requires active attention and knowledge, and an active and strong core.  Learning how to find a healthy neutral pose for your pelvis and spine is a topic that you will continue to refine and perfect for many years.  I’m still getting better at this, and I’ve been thinking about it for a long time!  The following are a couple good resources that I’ve found which I recommend reading:

• A short page on finding a neutral pelvis for sitting. The rest of this site contains more useful data about healthy posture and is worth exploring.
• An in-depth paper on neutral pelvis and spine

And finally, remember that if you are sitting without a backrest it is essential to maintain a good posture!  If your head is forward and/or your back is rounded (Figure 3), you are putting unhealthy strain on your body.

Staying in Motion

In my previous post about sitting I discussed the changes to your muscles which occur when you sit in a static position.  Your body actively lays down collagen fibers and glues muscles together – a process which is reversed by keeping the muscles in motion.  In general, this is a smart thing for the body to do because muscles that are not actively being used become more rigid and thus require less energy.  Yet when we sit in a static posture all day, we end up with glued together rigid muscles that do not serve us well when we try to stand up and walk around. It is also worth remembering that our brain has primarily evolved to coordinate motion (“The Brain is For Motion”), and staying active keeps us alert and mentally engaged with our bodies.

Active Sitting helps avoid tight muscles by keeping our body dynamic.  Instead of passively relaxing into a backrest, or rigidly holding a static “correct” pose, Active Sitting is about staying in motion all day long.  When our pelvis is upright we are well balanced and free to move our body as we work.  I often find myself moving and dancing in my chair slightly as I work and listen to music.  Once I lean back into my backrest or lean forward onto my elbows, I notice that I move less.  Such small motions may not look like “exercise,” but they do have a significant impact on our health.  Primarily these motions keep our muscles dynamically active – engaging and relaxing, and lengthening and shortening – a process which keeps them from binding up and turning off.

We can take this approach one step further by intentionally destabilizing the surface we are sitting on and requiring our body to actively balance and dynamically adjust its posture the entire time we are sitting.   The easiest way to do this is by sitting on an air filled sitting disc .  When sitting on these discs your body actively tries to keep your head level (to simplify vision processing) by constantly adjusting and balancing long chains of muscles to compensate for your weight shifting with each motion you make.  Using a sitting disc can turn the simple act of rotating your head into a full body action, engaging muscles all the way from your head to your feet.  It is this type of dynamic engagement that keeps our muscles alive and active!

There are many air-filled exercise discs out on the market and I have tried a few of them.  The first ones I used were intended for standing balance exercises, such as this one. While they were a good place to start, I found that they were not wide enough for my seat and were too tall.  I eventually found the 15” sitting disc from FitBall, which has been my favorite disc so far.  It is wider, so my sit-bones fit on it, and has a lower profile, which is ideal for sitting.  I have also recently found an even wider sitting disc – the 24” disc from AeroMat – which I think would be great for larger folks like myself (I’m 6’6” tall), but I have not yet tried it.  Finally, some friends have spoken well of the Fitter First 15” Sitting Disc.

A sitting disc is easy and inexpensive to incorporate into your existing office setup and to start exploring Active Sitting.  It is important to note that you should not expect to sit on them continuously for the whole day.  Rather, use them for half an hour at a time, taking them on and off your chair throughout the day.  Since they make active use of your core muscles, once you fatigue it is easy to unconsciously prop yourself up somehow and circumvent the destabilization that the disc offers.

Take Your Time To Train

When I first started practicing Active Sitting, I would try sitting without using my backrest for 30 minutes or less. Like any new sport, you have to train and condition your body for the activity. Besides simply building up strength and endurance in your back and core muscles, it is likely that you will have to stretch and lengthen muscles that are chronically tight from years of passive sitting. When I started my hips were too tight and my pelvis would stay rotated backwards making it difficult to sit with a neutral pelvis (See Figure 4 and discussion in my previous post). Until I was able to loosen my hips and legs enough to find a neutral pelvis, I found it very hard to sit without back support.

Figure 4 Short hamstrings contribute to tight hips and limited flexion. This combination of short hamstrings and limited hip flexion can pull your pelvis into a backward tilt, making it difficult to sit with a neutral pelvis -- even in the best fitting chair.

Even now, after many years of Active Sitting, I still find that I get tired and cannot sit all day without using a backrest.  So, don’t feel like you have to be able to do this for eight hours straight – that is really challenging!  My solution is to have a variety of different ways to work – from standing, to sitting on a tall saddle stool, to sitting on a regular chair with a sit disc, to simply collapsing back into the backrest and resting while continuing to work.  Whenever I feel myself becoming tired of one pose, I switch to a different one. Sometimes I just lay down on my back on the floor to relax for a while.

It is worth remembering that this is a life long practice with many interdependent aspects.  You cannot simply rip the backrest off your chair and suddenly find freedom.  You need to start with the body you have today and figure out what is the best path forward for you.  Despite all the problems with atrophy and dependence that supportive devices cause, they can be the right short term solution.  When you break your leg, using crutches is a good idea.  Doctors will try to get you back to weight bearing as quickly as possible so that your leg muscles do not atrophy – a quick process that happens in a matter of weeks!  The same is true of back support.  If you are in crisis – if your back is actively in daily pain – you may need better support in the short term.  The key is to understand that the support is not the long-term solution – it is only useful to help you while you initiate the strengthening and healing process.  Ultimately, the right solution is to have a strong, flexible, and active body, and to use equipment that helps you stay active, strong, and in good alignment.

The process of strengthening and healing your body after a life time of sitting is a complex topic beyond the scope of this post, but which I hope to discuss in detail as I continue to write. The good news is that it is possible!  Our bodies are amazingly adaptable and will adjust to a change in our daily patterns.  The more aware and knowledgeable we are of our bodies, the better we can be at healing ourselves.   But even with lots of knowledge and physical conditioning I have found that I sometime need further help and have gained great benefit from regular bodywork such as chiropractic adjustments, massages, and acupuncture.  Finally, I’ve benefited from active physical training by excellent teachers I have found in the Anusara Yoga community and a number of physical therapists I have worked with.  For a short introduction to alignment principals of Anusara Yoga, and how the physical practice relates to our mental and emotional lives, see my previous post “Melt Your Heart”. So, have fun regaining use of your body while you sit, and I will follow this up with more posts on saddle stools, sit-stand desks, and many more tips for staying healthy while working.

Over the last number of months I have been giving an hour long presentation which has been *very* well received. My goal is to highlight exciting insights into how we humans function and help you understand yourself.

Below is the Abstract and below that you will find copies of the slides.

“What Can the Study of Human and Robotic Motion Teach Us About Our Brains and Bodies?”
Abstract:
There is a fundamental connection between understanding our daily human experience and researching robotics.  This connection is Motion.  Because our brains exist to coordinate motion, if we wish to understand how we think, feel, and relate to others, we should start by understanding how we move.  Robotics is also fundamentally a science of Motion, spanning the range from motor controllers to advanced algorithms for world modeling and deciding where to move to.  This talk will integrate lessons learned from many robotics systems (both NASA built robots and others), and emerging theories of human physiology and neuroscience to paint an integrated picture of how our brains and bodies work together to create coordinated actions in a messy dynamic world.  In the process we will see that unlike computers, our brains are organized around timing, rhythm, and synchronization, and that human qualities like self-awareness may be the side effect of the computational requirements of intentional motion.

Bio:
Vytas is a Senior Robotics Researcher in the Intelligent Robotics Group within the Intelligent Systems Division at NASA Ames Research Center. He is currently leading efforts within the group to develop new biologically inspired approaches to robotic systems which interact safely with humans and the environment. Recently, Vytas lead development and field-testing of the Footfall Planning Software, which enables operators to plan walking sequences over complex terrain for the ATHLETE family of six-legged lunar robots. Prior to that Vytas was the Manager of the ArmLab, where he investigated non-dexterous robotic manipulation of the environment.

Vytas has been developing new robotic technologies and leading start-ups since he graduated from Stanford University in 1998. Most recently he took at 1.5-year break from NASA to be the CTO of Apisphere Inc, a Berkeley based startup that built a cloud-based system for delivering location triggered services to mobile devices. His first start-up in 1998 was Mobot Inc., which built fully autonomous robotic tour guides for museums – some of the first publicly, deployed social robots to autonomously interact with the public.

In parallel with his career in Robotics Research, Vytas has been a life-long student of human motion in many forms, including yoga, dance, martial arts, and (consequently) many forms of physical therapy.

Upcoming events where I will share this talk:

• July 12, 2011, Tech Academy of Silicon Valley, San Jose State University, CA

I’ve given this talk in the following Venues:

• February 3, 2011 – Department of Electrical & Computer Engineering Research Colloquium, University of Idaho
• April 8, 2011 – Yuri’s Night Education Day, NASA Ames Research Center, Mountain View, CA
• April 12, 2011 – Intelligent Systems Division, ASR Seminar, NASA Ames Research Center, Mountain View, CA
• April 13, 2011 – Santa Clara Valley IEEE Control Systems Society event in Sunnyvale, CA.
• April 26, 2011 – Human Systems Integration Division, NASA Ames Research Center, Mountain View, CA
• June 23, 2011 – Meeting of the Consciousness Working Group at the Institute of Noetic Sciences, Petaluma, CA
• July 2, 2011 – Priceless Art and Music Festival, Belden, CA

Many folks asked for the slides from the presentation, though I must admit that since they are very image heavy, they may not make a lot of sense for those who have not heard the talk.
PDF version as of April 13, 2011
Full tarball with video’s etc. from April 26, 2011

Please contact me if you would like me to present this at your own event. It is intended for the general public.

Your Body Adapts

The first principle to understand is that your body (and brain) physically adapts to how you use it.  We all know about sport specific adaptation – like bikers who develop strong leg muscles, or rock climbers who have strong arms.  While stronger muscles sound like a great result, adaptations that help you specialize for a specific task may make it more difficult for you to do other tasks. I know weight lifters who bench press enormous amounts of weight, but who can not cross their arms in front of their body any more.  As athletes train daily for the specialized set of actions required by their sport, they become very good at those actions, but can throw their bodies out of balance leaving them prone to injury when doing other things.  This is one reason that cross-training is popular and helps prevents injuries – it keeps an athletes body prepared for a more general set of motions and avoids overly specializing for a single set of actions.  Now, take a moment to think about how much time you spend sitting every day.  Besides being at work, you might sit in your car commuting, then sit while eating at each meal, then you also sit while watching TV or surfing the internet reading blogs like this one.  How much time do you actually spend moving?  Your body adapts to whatever you do, so if you spend long hours every day sitting your body will adapt to be “better” at sitting – and possible worse at other things — like walking! So, always remember to cross-train for sitting and include as much motion in your day as possible.  Along with motion, knowledge about the adaptions will help you understand the impacts of sitting, and they fall into three major categories: muscle atrophy, muscle shortening, and fascia binding.

Muscle Atrophy

Muscle atrophy is a concept that most of us are aware of.  We know that if we do not use our muscles, they will get weaker.  It takes constant energy to feed muscle bulk, and our bodies are efficient – if we are not using the muscle it naturally starts to atrophy since it is a wasteful use of resources to maintain unneeded muscle.  The primary daily use of our muscles is to move us around while counteracting gravity.  Because gravity is so omni-present we tend not to think much about it, but it is a constant and significant force that we expend a lot of energy engaging with.  Sitting passively we reduce the need to counteract gravity and do not demand much out of our bodies – leading to atrophied muscles and weakness.  Weak muscles are a problem because they will leave your joints unstable and prone to injury, or otherwise pulled out of alignment by other chronically short, tight muscles.

Muscle Shortening

Besides adapting your muscle bulk, your body also adapts the length of your muscles.  Your muscles are strongest in the middle of their range of motion, loosing power at extremes of extension or contraction.  Therefore, it is most efficient for the natural resting length of your muscles to be in the middle of the normal range of motion that you experience.  This adaptation allows the muscle to have the most power for the least effort through the majority of expected motions.  Therefore, your body will literally change its shape to accommodate the poses and movements that you normally experience.

Figure 2. Tight hip flexors pull your pelvis away from neutral alignment into an anterior tilt, which strains the lower back.

Figure 1. The iliacus and the psoas together make the iliopsoas, a deep and powerful hip flexor

All the time we spend sitting at desks and sitting at home encourages a pattern of shortened hip flexors.   One of our most important and powerful hip flexors is the iliopsoas (Figure 1), a two headed muscle which runs from the inside of our lower spine and the top of our pelvis down to the upper portions of our femur bone.  With the pelvis fixed in place, contracting this muscle causes you to lift your leg (like a seated pose).  Conversely, when standing with the femur bone fixed in place, contracting the iliopsoas causes the pelvis to tilt forward (anterior rotation – figure 2a).  Therefore, when you sit all day the iliopsoas is held in a shorted position (Figure 3b) and slowly adapts over the years causing your pelvis to tilt forward (anterior rotation) and putting a lot of pressure on your lower back.  Thus, your adaption to sitting has made it more difficult for your body to stand upright because that requires your iliopsoas to be in a longer looser pose (figure 3a).

Figure 3 Muscles shorten when you sit.

The shortening of the hip flexors is only one of the problems caused by sitting.  The hamstrings, which are the largest and most powerful muscles in the body, also become shorter.  The hamstrings connect from the bottom of the pelvis to the upper portions of the tibia (shin bone – figure 4).  Thus, sitting with your knees bent your hamstrings hold a shorter pose than required while standing (figure 3).  Since the hamstrings attach to the back of your pelvis, they pull your pelvis in the opposite direction as your hip flexors.  This can cause the lower back to flatten past the point of a healthy neutral spine and can be a source of many lower back complaints.

Figure 4. The hamstrings connect from the bottom of the pelvis to the top of the tibia (shin bone).

The shortening of the hip flexors and the hamstrings tilt the pelvis in different directions.  While you might think, “great! Its all in balance!” it is not.  As the hamstrings and the iliopsoas fight each other they both get tighter and tighter.  This reduces the range of motion of your pelvis and locks it into place, often far from a healthy “neutral” pose (Figure 2b).  It is a vicious feedback cycle that makes it increasingly difficult to achieve a healthy alignment, even when you try, since the tight locked muscles will keep pulling you back out of alignment.  When you want to unlock stuck hips,  the solution is, of course, a combination of knowledge, stretching, strengthening, and bodywork.  Think of this as cross-training so that you can be good at both sitting and walking.

Fascia Binding

In another earlier post (Fascia, Collagen, Motion, and Bodywork) I discuss how our body is constantly laying down new collagen fibers, somewhat at random.  As we move we break the fibers that grow between the moving surfaces of our muscles.  Thus, the body adapts to its usage by stiffening up sections that don’t move much and keeping smooth sliding surfaces in the areas that see lots of motion.  Like our body efficiently letting unused muscles atrophy, the body uses this process to save energy on muscles that are held chronically tight.  When keeping a muscle constantly clenched, the slow build up of the collagen fibers is similar to a tree trunk becoming more fibrous and woody.  As the muscle binds up and gets stiff, the body spends less energy clenching the muscle and instead passively relies on the tree trunk it just grew.   Thus, when spending most of our time sitting, our muscles slowly glue together in that pose, decreasing our range of motion and eventually getting so stuck together that we can no longer get the muscles unstuck simply by moving.  For more on this, see my earlier post.

Why Sitting Will Kill You

The good news is that you are unlikely to keel over and die directly as a result of sitting.  Sitting kills as an indirect result of the physical adaptations it causes.  As your body adapts to sitting and becomes less well suited for other activities, like standing and walking, you increase your likelihood of a major injury.  Having tight, weak muscles may still be sufficient to get you through your typical day — shuffling from work desk, to car, to couch, to bed — the danger is when the unexpected happens.  When you slip, trip, or otherwise have a sudden need for your body to perform, you need a strong, flexible, reactive body to be able to catch yourself safely.  Everyone trips, everyone slips, the unexpected is guaranteed to happen eventually, and if you are too tight and weak to catch yourself you end up falling and breaking something like your hip or arm, or throwing out your back.  These injuries can directly kill you or cause a severe degradation in your quality of life.  The most frustrating is when the injuries cause you to tighten up even more and you further limit your physical activity — starting the downward spiral that leads to further injury and physical decline.

There are many ways to avoid this sort of downward spiral.  Staying active, exercising, strengthening, stretching, and managing your weight are all well-known goals (more on them eventually).   Think of this as cross training for sitting!   Knowledge is the best place to start — so you can guide your physical efforts well.  To learn more about how specific muscles move your body in use-dependent ways, I highly recommend reading the Anatomy of Movement. This is the best book I’ve found for someone who wants to learn about their own anatomy and start to understand which muscles make which motions.  It is an easy and accessible read which I think everyone should take a look at.  To read more about how short tight muscles can disrupt your tension network and cause problems throughout your entire body, please see my earlier post on Fascia, Bones, and Muscles.  Finally, it would be a good idea to get up and go stretch and walk around right now!  Here is a good introduction to stretching following the principles of Anusara Yoga. (See also my earlier post on Anusara: “Melt Your Heart”.)

Keeping with my current focus on Office Ergonomics, my next post will discuss Active Sitting and how we can minimize the undesirable adaptations caused by long hours at the desk.  On the sidebar to the right of this post I’ve added a few quick reviews for the items I personally use, and will give more detailed discussion in future posts.