Seeing all this P90X topics I dont think i saw a post about the Insanity workout. If you want to burn fat fast do the insanity workout follow the nutrition it has and the guidelines and you will deffinatley have results, I have to start it up again i did it for 2 weeks and already started to feel a whole lot healthier waking up happier and more energized, I'm not fat but have some body fat I want to get rid of on my mid section. Had my top part of abs starting to show when I flexed them. After stopping for about 1 week started to wake up like crap eating unhealthy (damn fast food) lol. About to start up again and do it outside in the garage where its hotter and fresher air (had air conditioning in the house still sweat a whole crap load)