There's a reason people say that "speed kills." It's the difference maker in nearly every sport, and it can make or break you as an athlete.
Not everyone has the genetic potential to be Usain Bolt, but everyone can get faster. Follow these principles to make the most of your speed workouts. (Also try the Sprinter's Speed Workout.)
You have to train yourself to run fast. That means developing speed "muscle memory." Perform every sprint at (or close to) maximum speed. You can't train by performing sprints at only a percentage of your maximum speed and expect to teach your body to run at full speed.
Sprinting at maximum speed requires proper technique, so you must avoid excessive fatigue. Sprinting when you're tired results in poor running mechanics and slower speeds.
Strength training is—and should be—an important component of speed training and development. It's best to perform lower-body lifts that strengthen multiple muscles at once, such as Squats, Deadlifts and RDLs. And since they improve acceleration and overall power, plyometrics should be an important part of your workouts.