Last week, I started doing Shaun T's Insanity workout while eating high fat low carb not to lose weight as I've done in the past but to see what it will do for my body that's already in good shape thanks to what I've been eating for over 2 years.

I like Insanity because it's pretty much entire body workout with a lot of cardio so for the time it takes to complete one session (40 - 45 minutes including warm up, stretching and cool down), I get good bang for the buck as far as workout results go.

Some of the exercises are tough on the knees so I modify them because I've had problems with my knee in the past but other than that, Insanity has been my choice.

What's your favorite workout program?