I believe wholeheartedly in the importance of joint EXPANSION, especially with regards to the spine. Every joint in the body has the ability to expand and to contract. When a joint expands, a small amount of fluid is released, maintaining optimal performance. This is the action of a healthy joint.
The expansion of the spine is essential to good health, because it is the link between the brain and body. Too often, people compress their spine, resulting in numerous health problems. Instead, one should get into the habit of elongating the spine.
Imagine that a string is tied to the top of your head and is being pulled to the sky. At the same time, tuck your hips. The tucking of the hips is opposite to sticking one's butt out. Sticking ones butt out causes the joints of the lower back compress, creating pain and severe back problems.
To give you an idea of what the proper elongation of the lower spine feels like, lie on your back and pull your knees to your chest. Now, doesn't that feel better.