Click here to start INSANITY now.
Right behind P90X on the popularity index right now is INSANITY, and it's exactly what the name implies. Created by and hosted by Shaun T, the star behind Hip Hop Abs, you'll follow a non-stop training session of plyometric drills coupled with aerobic and anaerobic intervals. Discipline and strength are required to get you through this sweat-inducing workout that can burn 1,000 calories in an hour. Stick with it for 60 days and you'll see dramatic results.