I tried "Get Ripped 1000" by Jari Love once. It was pretty tough. Each sequence has a calorie count on the side of the screen. Supposedly after doing all the moves (and not doing the "beginner" moves) you burn 1000 calories. It's definitely a vid to grow with, but I can't stand the woman's monotone voice. Her body is really shredded, though, so I'm guessing she must be doing something right.