Potential oversimplification alert: I’m now going to describe some main types of fast workouts. I’m choosing these few types because they’re each a targeted way to improve an important aspect of running faster. Nitpickers will say that you can’t compartmentalize running like that; they’ll say that all faster running improves several aspects of running fitness. And they’re right—you can’t say that something like a 3-mile run at the pace you can hold for an hour has only one narrow, easily identified benefit.
At the same time, there are a few key types of workouts that the best runners in the world do over and over again. Each of those workouts are among the most effective ways to improve an important element of running performance. When you understand those few key types of workouts, you can better understand how and why to do them all to become a more complete runner.