Sitting seems to be a fairly innocuous activity on the surface of things but, it turns out, it’s much more difficult than you might think. When sitting, the assumption is that our muscles are relaxing. But I’ve been finding that is not the case. When we sit down on a firm chair, we feel our sit bones or rear end in contact with the chair. Most people assume this is happening symmetrically. I’ve found, though, that many people with back pain or sciatic pain sit asymmetrically, loading one cheek a little more than the other.
Try this out: sit on a firm chair in your natural sitting position and then close your eyes. Do you feel you’re sitting on one cheek a little more than the other? You’re not alone! Let’s just say you’re sitting on your right cheek a little more than the left cheek. What I’ve found is that the left waist muscles (internal obliques, external obliques, and possibly the latissimus dorsi) are activated because they are, in essence, holding up the left pelvis. As time rolls on, these muscles contribute to a side bending pattern which stresses spinal tissues such as vertebral disks or nerves exiting the spine composing the sciatic nerve. So the sciatic pain might be on the left side as a result. Because your pain is on the left side, you may shift more to the right cheek to avoid it, reinforcing the root cause of the issue.
“Well,” you might say, “that’s because sitting on my left cheek increases my back pain or sciatic pain!” Good point. But maybe it increases your pain because of the way you are shifting to the left cheek. Remember over the years, you’ve taught those left side waist muscles to contract by sitting on the right cheek. So when you shift to the left, they remain contracted, but are now loaded a little more. You must become aware of this and lengthen your left waist muscles. I do this through a specific series of exercises with my clients but you may have luck by be putting your left hand on your head to help you lengthen that left waist. Give it a try and see what you think!