Hard sells, contrastingly, embraced the workout. They demanded the workout. They not only acknowledged how many glazed fritters the customer was going to have to give up, they made it a veritable mantra. Dig Deeper. Push Harder. Get Fit or Get Out. The hard sell was perhaps best embodied by NBC's The Biggest Loser, a sixty-minute prime time blitzkrieg of sweat, tears, and drill-sergeant-esque instructors. Contestants came on at 300 pounds, left at 150; weighed in at 250, weighed out at 120. Meanwhile, its host, Jillian Michaels, parlayed the show's success into a media empire as sprawling as Martha Stewart's.

The genius of the hard sell, of course, was that it wasn't a sell at all. As Beachbody executive Laura Ross put it, "We were just trying to be honest. If you wanted to get results, you would have to work your ass off." And therein lay the savvy of it: in an era of quick fixes, Insanity made logical sense. It asked for sixty days, every day. It asked you to sweat like it's monsoon season. And in return it promised a body as tight as rubber and as hard as sin.

***

To distinguish Insanity from P90x, Beachbody picked to star in its videos a relative unknown named Shaun Thompson. He had been teaching classes at the local Equinox in Santa Monica when he met Ross, who invited him to submit demo videos for another Beachbody program called Hip Hop Abs. They ended up being so good that he was signed not only for that series, but also for Insanity.

"It was obvious from the get-go that Shaun was extremely talented," Ross said. "Sometimes in fitness videos because of space constraints we end up doing movements that seem super contrived, super restrictive. But Shaun used to run track, he used to dance, and you can really see that in his posture, how he holds himself. He brought a natural athleticism to the exercises."

Insanity was nearly a year in development. In a way that would have been inconceivable to the likes of Jane Fonda, the modern fitness video is a meticulously choreographed beast, the product of concept meetings, design docs, A/B testing. Thompson spent hours working through single movements at the gym. Versions were edited, then re-edited. His last name became the snappy, monosyllabic T. The final version was tested on a focus group of 60, whose physical transformations were then sliced into a twenty-minute infomercial that would form the lion's share of Insanity's publicity plan.

"From the beginning, we knew that Insanity would be marketed primarily on television," Ross said. "We just had no clue that it would be so successful. And so every year, we've reshot the video. We send out a call, people mail in their before and after photos, their testimonials, and we feature those right alongside the professional stuff."

The result was a surprisingly seductive grassroots production -- people who started out looking like you and I, gradually doing things that you and I couldn't do with two more legs and a sledgehammer. In one segment, a forty-year-old mother of three whipped out a set of pull-ups, nary a love handle in sight. In another, Daikeler himself appeared shirtless, mugging for the camera. "Why didn't I have this body in high school?" he asked breezily. "Do you know how much more fun it would have been?"