Sitting Exploration 1
Sit on a chair with a firm seat whose height places your pelvis at least as high as your knees.
Before getting started, let's clarify what we mean by tilting the pelvis either forward or backward. If I ask you to tilt your pelvis forward, I mean that you should tilt the top of your pelvis, just below your waist, forward. If I ask you to tilt your pelvis backward, I mean that you should tilt the top of your pelvis backward. About half the people I teach initially think that tilting forward is really tilting backward and vice versa. I use this terminology repeatedly throughout the book, so make sure you know its correct meaning.
First, tilt of your pelvis backward. Think of it as a ball that is rolling toward the back of the seat.
Next, tilt your pelvis forward, as if it were a ball rolling toward the front of the seat. Continue to tilt slowly backward and forward and observe what happens in other parts of your body as you do so.
When you tilt your pelvis backward, notice how your head drops down and your chest caves in. The curve of your lower back is reversed because the weight on your pelvis is now behind your sit bones. Feel how your back muscles relax when your head and chest are slumped forward.
When you tilt your pelvis forward, notice how your chest and head come up automatically, without you pulling your shoulders back. The chest and head come up as the lumbar curve increases.
Sitting Exploration 2
In this exploration, you will sense how it feels to sit on different parts of your sit bones and how that affects the posture of your back.
Tilt your pelvis backward and forward, as in Exploration 1. As you do this, sense the weight and pressure of your sit bones against the chair seat. There will be one place where your weight feels most concentrated on each sit bone. That is the point at which you are directly over the bony prominence of each sit bone.
As you tilt your pelvis backward, feel how your weight goes behind the bony prominence. If you exaggerate this movement, you will eventually be sitting on your tailbone.
As you tilt your pelvis forward, feel how your weight will again pass over the bony prominence. If you continue to tilt beyond the prominence, you will be sitting on the flat section in the front of each sit bone.
Now let's find a comfortable sitting position. First, sit with your weight on the bony prominences of your sit bones. Tilt your pelvis forward a little bit until you can feel your weight on the flat bones in front of the prominence, which will feel like small platforms. It is easy to sit on the front of your sit bones because the area is flat.
Notice the curve in your lower back as you sit on the front of your sit bones; your lumbar spine is automatically in its natural curve. Think of this as your home base for sitting. It is an easy way to reestablish the feeling of your natural lumbar curve.
Continue to sit on the front of your sit bones for another minute or two. Be aware of the positioning of your chest and head. Is it any different than usual? Imagine you are carrying the sky on top of your head. Experiment with how much you can relax your back and abdominal muscles while remaining on the front of your sit bones. The more aligned your pelvis and spine are, the less work your back and abdominal muscles need to do.
I call this pelvic position the "neutral tilt position," meaning the amount of tilt in the pelvis that provides the most support for the spinal curves and the carriage of the head. Some people have been taught (incorrectly) that the neutral tilt of the pelvis is found by sitting on the bony prominences of the sit bones, but that is actually a backward tilt.
Excerpted from Pain-Free Sitting, Standing, and Walking by Craig Williamson.