What can you expect from a workout dubbed Insanity? Do you really have to be nuts to try "the hardest workout fitness program ever put to DVD," as its website describes it? Probably not, but you have ...

Shaun T. is the mind behind the viral "Insanity" workout. In his new book, "T is for Transformation," Shaun talks about what motivates him to exercise. Shaun told Business Insider that you shouldn't ...

Seriously. Mr. T shows zero mercy. If the program is 50 minutes long, he'll give you maybe 2 minutes total to rest, wipe up the pools of sweat under your feet, and sip some water. The rest of the time ...

Shaun T. is the mind behind the viral "Insanity" workout. In his new book, "T is for Transformation," Shaun talks about what motivates him to exercise and what he does when his body doesn't need a ...