On the soccer field, quickness is a two-headed beast. "Speed and agility are key for a forward," says Hughie O'Malley, M.D., director of the U.S. Soccer Sports Medicine Committee. To improve your speed, he suggests adding intervals to your training. A typical workout might consist of seven 30-meter sprints with 25 seconds of recovery in between. To mimic the fast-and-faster nature of soccer, O'Malley also has his players do fartlek runs—long medium-paced runs interspersed with randomly spaced sprints. Build your strength until you can go full-out for the length of a soccer field. For agility, O'Malley has his players do zigzag runs around cones or flags, spaced at least two running strides apart. Once you're zipping through the course like Mia Hamm around a couple of hapless defenders, try running the course backwards. And don't put the ball away until the season starts. If you're working out three times a week, O'Malley suggests doing speed and agility work on Mondays and Fridays and skill work on Wednesday to allow for recovery.