I haven't read this book, but had terrible back pain due to these very issues. Certain muscles in my back had atrophied to the point that I could not hold my sh

I haven't read this book, but had terrible back pain due to these very issues. Certain muscles in my back had atrophied to the point that I could not hold my shoulders down and back without a lot of strain to do so. This resulted in a great deal of tension in my neck and other muscles that had to take up the slack. I went through physical therapy to strengthen the back muscles that had atrophied. The exercises were very hard and rather painful, but after several months, they worked like a charm.