My sister and brother in law do it and the more intense version called insanity and it is insane o.o My sister loved it so much she's now going to school to be a personal trainer. She wants me to do it and I started but then that's when I got really sick and I haven't been able to start it again.

She wants me to do it now but I instead went swimming at the lake today than start =x

I developed asthma though and it's pretty tough if you do it right. Plyos really so I have to start something else to build my lung strength up. It's a cool program though.