Med ball floater
Everyone wants to throw the medicine ball, but as you'll see, the ball doesn't even have to go anywhere to get you moving. Just set up as shown, then synchronize with your partner to do a series of quick stance and hand switches. Switch your whole body from right to left: the ball stays right where it is. The motivation will be obvious; if you move too slow, gravity wins and the ball falls to the floor.
Special thanks to Steven Stanfield, Studio 122, for his flash of inspiration.
