Elements from the Army's physical training program are mixed with loud music, state-of-the-art equipment and a hardcore attitude. Sound slightly sadistic?

Well, if you're reading this, there's probably some small part of you that likes the idea of having your butt kicked. Enlisting under the command of drill sergeant Barry Jay and his cronies gets many a devotee in shape without any sort of weapons training. It's simple: At this camp, there's one workout room, one trainer, one hour-long take-no-prisoners session. If you're looking for a sauna or pool, you're outta luck, soldier: This ain't no spa. Most weekdays the first class starts at 5am, and if you're late, Jay will call you at home! The first half of the class consists of heavy-duty cardio on treadmills, so come ready to power up and down some imaginary hills. For the second half of the class, recruits students must be prepared to give all with barbells, weights and resistance tubing. And yes, there will be push-ups. Lots and lots of push-ups. —Dan Wool