This book is so great that I am showing women at the gym how important the Psoas Muscle is to the body,the emotions, and staying limber. The information Liz Koch presents is extremely worthwhile knowing. I have found that working out can make my body tight and less limber. What I do, for example, work upper body like shoulders and arms and chest then I go to the mat and work the upper Psoas muscle. When I do squats and work the lower body and get tightness or pain in lower back and buttocks. I go to the mat and work the lower Psoas in my body. If you like to body build this book is a way of staying limber and having less soreness. Also, I have learned that when the Psoas muscle shrinks, fatigues or dries out, there is the strong possibility how we may have lots of back pain and how the upper back can become rounded. I am impressed with the knowledge I have gained from this book.