I just turned 48 last month, and yes I'm doing Insanity and loving every insane minute of it. I am not following Shaun's rotation because I wanted to feather Insanity in with my vast array of other nosebleed workouts, both home-ex DVDs and my aqua stuff, so I'm doing Insanity cardio on Sunday mornings, as well as alternating his Insane ab routines on Sunday mornings. Also this coming Monday I'll use Cardio Core Recovery (title?) as a chaser after my power step routine, and Cardio Recovery after my Wed. routine.
I love, love, love Insanity. I've been able to complete all the drills without flaming out, although every now and then (okay, okay, VERY FREQUENTLY) I need to pause more often than the workouts call for for water breaks, but I can just feel myself getting stronger and more powerful with Insanity in my life. And I love, love, love Shaun T - he's the perfect complement to Cathe!
A-Jock