I started Jillian Michaels 30 Day Shred on Wednesday 2/15/12. Boy oh boy did I have to modify it, but I got through it with all the modifications. I can not do jumping jacks, well not more than five of them anyway and that is most of the cardio in session 1. I also couldn't do the butt kicks. I did a lot of marching in place to keep my heart rate up. I am certain this will get easier, but WOWZA it is hard to do. I want to keep up my work on the treadmill too while doing the 30 day shred. I may be biting off more than I can chew. I really don't like exercising every day.