Fads come and go, but since 1994, the Spinning program has helped millions worldwide lose weight, gain energy and get into the best shape of their lives.
Spinning is an aerobic exercise that takes place on a specially designed stationary bicycle called (obviously enough) a spinning bike. As you pedal, motivating music plays and the instructor talks you through a visualization of an outdoor cycling workout: "You're going up a long hill now, you can't see the top yet...."
During the class you vary your pace -- sometimes pedaling as fast as you can, other times cranking up the tension and pedaling slowly from a standing position. This helps you to focus inwardly and work on your mind as well as your body.