I received my P90X DVD's and began the classic rotation on Monday, so I just finished day 4 (man, Yoga X is so hard!) I've watched all the DVD's one time through just to get familiar with them. Is it my imagination or is there alot of strength training without weights? I realize that some workouts use all weights like Shoulders and Arms, but there seem to be alot of workouts without them. Not that there's anything wrong with that. I'm just wondering if I'll lose any of the muscle I've built with all the Cathe weight work I do. Can anybody fill me in on their experience with this versus Cathe?