Good posture. It makes you look taller and more confident. Studies show that higher ranking individuals in business and government stand up straighter, and that people with good posture are actually more likely to be shown respect and given higher ranking positions. Socially, a straight stance sends the message that you are comfortable and in control. In addition standing up straight helps you look thinner.

The benefits don’t end here. Good posture is actually critical to maintaining a healthy body. Back pain is now the second most common cause of lost work days behind the common cold. Knee pain, elbow pain, and neck pain bother millions of people. All of this pain is exacerbated (and frequently caused) by bad posture.

In brief, bad posture alters the tensions on joints. Altered patterns of tension lead to joint ware. Every joint in the body is designed to allow you to move with minimal friction. For this friction free movement to happen, the bones, tendons, and ligaments in a joint all have to line up the right way. If they don’t, they tend to rub up against one another creating friction, which leads to inflammation. This inflammation damages joints, ultimately resulting in pain and injury.

So how are our joints meant to line up? For the most part, everything is meant to point straight forward. Both feet should point straight ahead of the body. The knees should line up directly over the feet. The hips should lie flat, not tilting forward, backwards, or to either side. Starting from the hips, the spine should gently curve in, then curve back, leaving the neck and head pretty much straight at the top of the body. Finally the arms should fall directly to the side of the body, with the elbows pointing straight back and the elbow pits pointing straight forward.

These days very few people stand this way, with the exception of models, who are taught to because it looks so much better. But if this is the way our bodies are designed to stand then why is good posture so uncommon? Like so much else that goes wrong with our bodies these days, our poor posture is ultimately attributable to the ways that our lives here in modern day America differ from the environment in which we were designed to live (see What is ReEvolution for more). When it comes to poor posture the culprit is a seemingly innocuous activity that virtually everyone does through most of their day: sitting in chairs.

How Sitting Can Distort Posture

The rest of the material on this page is a LITTLE bit technical (sorry!). If it's not to your taste, just skim the next few paragraphs - the details aren't as important as the general theme. There's a demo at the end that will hopefully make the essentials clear.

How on earth can sitting in chairs lead to poor posture? The key lies in something called Davis’s Law. Davis’s law describes how muscles adapt to the positions we hold them in. It states that when muscles are continually held in a shortened position these muscles tend to become shorter, thicker, and tighter. On the flip side, when muscles are continually held in a lengthend position, they tend to become longer, thinner, and looser. In the seated position, some muscles are held in a shortened position, while other muscles are held in a lengthened position. As a result, some muscles become short and tight while others become long and loose.

Every muscle in the body attaches to a joint. When the muscles that attach to a joint change their length or tension, it affects the alignment of that joint. The primary muscles that tend to get short and tight as a result of sitting for hours everyday are the calves, the hamstrings, the quads and hip flexors, the lats (the long, broad muscles on the side of the back), the abs, the pecs, and the muscles on the back and sides of the neck. Tight calves tend to make the feet rotate out and can also change the alignment of the knee. Tight quads alter knee alignment, and both tight quads and tight hips, as well as tight abs and lats change the alignment of the hips and spine. Tight pecs pull the shoulders forward. Tight neck muscles throw the head forward, distorting the posture of the neck and upper spine. No need to remember all of that just now....

On the flip side, the primary muscles that get long and loose are the glutes (some of the muscles of the glutes anyway) and the muscles of the upper back like the rhomboids, middle trapezius, and the rear deltoids. The glutes serve primarily to extend the hips and provide forward thrust during walking and running. Loose glutes alter the alignment of the hips and knees. The upper back muscles (the rhomboids, middle trapezius, and the rear deltoids) all help to hold back the shoulders, creating an erect posture. When these muscles are lengthened, the shoulders slump forward, drawing the upper spine into an increased curve.

How Changes in Muscle Length and Tension Affect Alignment: A Demo

If you’re having trouble seeing how changes in the length and tension of muscles can alter the alignment of joints try working through this demo. Hopefully it will make everything clear. As a side benefit, the motions you’ll learn in this demo will come in handy when it’s time to start doing corrective exercise.

To start Stand sideways in front of a mirror and put your pointer fingers on your hip bones, and your thumbs on your "SI joints", which are the little bony bumps on your lower back a few inches outside your spine where your spine attaches to your pelvic bone. You should be able to feel your SI joints around the level of your belly button on your lower back (maybe an inch or so below).

Look at the alignment of your spine. Now, tilt your hips under you, squeezing your glutes, which will raise your pointer fingers (and your hip bones) above the level of your thumbs. As your pelvis tilts under you, notice how the curvature of your lower spine decreases. Tilting your hips under you eliminates any arch in your lower back. (It would have been nice if we'd actually told our model to move her arms out of the way of her lower back for this photo, but you'll see it in the mirror....)

Now reverse the motion you just did. Tilt your hips the other way, sticking your butt out behind you, and raising your thumbs above your pointer fingers. This should arch your lower back.

Practice moving back and forth between these positions a few times, alternately curling your hips under you flattening your lower back, and then tilting your hips forward by raising your backside up in the air, arching your back.