Quickie workouts that don't need any equipment are good for doing when you have a few spare minutes at the office, while on vacation, or during a hectic day at home when your regular routine just isn't going to happen. Click here for a series of moves that will energize you, rejuvenate you, and get your blood pumping all in just 12-15 minutes. Designed to exercise multiple body parts at the same time, it includes push ups, chair squats, ab crunches, close-stance wall push ups, and a move called the 'ab vacuum.' Performing one after the other and shooting for 20-25 reps of each should do the trick.