aerobics class

When it's time to hit the gym, most of us are in a serious time crunch. If your idea of a gym workout involves walking on the treadmill, riding the stationary bike or just doing laps around the track, you could be wasting your time.

Sweating up a storm with basic cardio feels good in the moment, but you won't be doing your muscles any favors with that routine.

* Would you flee in terror if confronted with a room full of sweaty people in spandex thongs?* Are you not immune to the occasional Van Halen-style air guitar jump?* Have you been known to push aside your coffee table and dance like crazy in your living...