I have always been a strength training kind of girl, but I wanted to try something different so I got a pilates book at Christmas. What I have is "The Pilates Body" by Brooke Siler, and the descriptions of how to do the exercises and how to use your mind to engage the muscles and improve your exercise efficiency, seem very good. I've been doing this for 6 weeks and really like how I'm feeling so far. I've been doing 2 strength training workouts (40 mins) and 2 pilates workouts (20-40 mins in length) a week. BTW, what Zone activity level would that be?? I think there is some kind of debate about whether pilates builds muscle or not, and I would like to know people's opinion about that as well. I used to jump rope but right now I'm not doing it (no time unless I do it at the same time as one of the above four workouts a week). So basically no aerobic exercise to speak of. And one last question, for a flat stomach, can I just do pilates powerhouse mat work or should I keep doing the crunches I have been doing with strength training?? I look forward to hearing from the experts! =) Thank you all, Kate