The Old Move: Stand in front of a 12-inch plyometric box (you can find them in most gyms or at performbetter.com). For one minute, jump up on the box and then back down on the floor as many times as you can. Do four 60-second sets, with three minutes' rest between each set.
Why It Still Works: Explosive movement best simulates the muscle-energy demands of skiing and the balance you need to shift from one turn to the next. "We would do these jumps on benches in Austria, says Gollner. "The world's best downhillers can do this for 90 seconds, but you'll probably shut down before a minute.