This book is a must for anyone serious about their abs, whatever their fitness level. It is clear and to the point on the subject. I have liked very much the the explanations on why certain abs exercises place undue stress on the lower back, and the importance of progression, acquiring strength in the abs before tackling taking on more challenging excercise. After reading this book, I will certainly avoid the 'risky' exercises. Anyone who has the 'legendary abs', will be familar with them. The explanation in the Complete Gude reaaly is more complete. I have also appreciated vey much the book's explanation of why posture, the pelvic tilt and the abdominal hollow are so fundamental.