A short, concise explanation of the importance of correct postural alignment:
https://www.youtube.com/watch?v=6oTfN5NDQWE
Excellent.
Tim, have you read this: http://www.bettermovement.org/2010/back-pain-myths-posture-core-strength-bulging -discs/
Interesting article, thanks Backarcher.
For anyone interested in more depth explanations related to the article, I recommend anything by Dr. John Sarno (especially "Healing Back Pain"), the pioneer in the field.
Dr. Sarno is an excellent resource.
some of older guys might remember this: https://www.youtube.com/watch?v=2B2IE0o7diU&hd=1