Upon reading 'Healing Back Pain', I came to understand that it wasn't the sitting but rather built up stress and anxieties causing the pain.
Within 1 week of reading, my back felt 80% better. Within one month, 95%. Several months later, I'm now pain-free.
My girlfriend also experiences anxiety at times and had back pain that would come and go. She read the book and it cured her back, as well.
Admittedly, I found it very strange how effective this book was. I approached it hesitantly, but it has had profound results. Check the reviews on Amazon for further support.
This book has had a great impact on my quality of life and I highly suggest it to anyone experiencing not just back pain, but any physical ailment that might be tied to stress, anxiety, tension, etc.