We’ve all been there. Your gym bag is all packed, but after a three-hour class and a rough night of sleep because your roommate broke up with her boyfriend again, a workout is just too much to ask of yourself. Instead of parking your bum on the couch for the rest of the day in your athletic wear (which are ironically the clothes that are most comfortable to do absolutely nothing in), you can still burn some calories without stepping foot in the gym. Heck, you don’t even have to put on sneakers.