By Mandi Bierly
December 10, 2008 at 08:00 PM EST

You don’t need to join a gym. Just close your office door and click on one of Mel Thomas’ FitHaven YouTube videos. Below, a sample from her “Dirty Dancing Fitness Salsa” class (131,882 views, at last count.)

(Shockingly, her “Fitness Pole Dancing” sample has only 7,143 views. Criminally, the “Flashdance Dancercise Class” clip has only 2,792 — the bloke upfront is trying so hard!)