Whether you are standing, sitting, sleeping, working, or relaxing, your spine is most comfortable in what we call a neutral posture. Neutral postures are positions about halfway between full bending and arching.
Your neutral spine has three natural curves: an inward curve at the neck (cervical lordosis), an outward curve at the upper back (thoracic kyphosis), and an inward curve at the low back (lumbar lordosis).
Neutral spinal curves vary in shape from person to person. They can also change - sometimes for better, with exercise and training; sometimes for worse, with aging, injury, disease, or poor posture habits.
The amount of curvature in your spine when you are in a neutral posture determines your support requirements. A spinal support's curves should be deep enough to support your particular curves without pushing beyond your neutral postures. It should feel natural. You should not feel too arched; nor should you feel unsupported, as though there were a gap between you and the support.
We describe neutral spinal curves in terms of a size: flat, average, and deep. Most people have average spinal curves. In our catalog you will find symbols near each product to indicate the spinal contour size each product supports.
Unless you know for certain that you have a deep curve (if you can't live without your lumbar roll) or flat curve (if you like the feel of your straight-backed chair), play the averages. If you order a product and discover that it does not fit, you can usually return it for a different size. Of course, the only way to be certain that a product is right for you is to try it.