What's the concept of the book??
You have to read it! He gives you thirteen rules to stick to.. I've lost like five pounds in a five days. He has you exercise five days a week for about 50-65 minutes, 30-45 being low-impact fasted cardio, and tells you what to eat, what to drink, but its not an overly restrictive diet. It's very effective. I'll live by his rules the rest of my life!
I've actually found the fasted cardio made me lose ALL muscle mass. If you don't want that, keep lifting heavy and even fasted, you should be fine.