As a fat chick I can tell you this game is amazing! Instead of quitting when I got too tired I wanted to keep going. It wasn't too intense and I didn't feel guilty like I do when I stop in the middle of one of those boring excersize videos. I was able to work up a sweat without feeling like I my fat butt was going to have a heart attack.
I do not recommend for TRex's, however. The ring has a design flaw that excludes them. I believe maybe a special extension for their tiny arms would be helpful.