And it will almost certainly improve your performance. The reason is confirmed by common sense: Varied workouts teach your body varied lessons. The long run teaches endurance, track work trains "fast-twitch" muscles, hills teach strength, etc. A well-rounded mix of workouts will help you improve your running form, condition your body to handle the discomfort of faster speed, give you a sense of appropriate pace, and build your end-of-the-race kick to the finish.
While the specifics of every training program should be adapted to the specific needs of the individual, the runner interested in improving performance should have a well-rounded program that includes some, if not all, of the following six building blocks:
- Fartlek (for speed and pace)
- Hills (for strength)
- Tempo Runs (for speed and pace)
- Intervals (for speed)
- The Long Run (for endurance)
- Easy run (for recovery)
Fundamentals
If you are a beginner runner, you may want to hold off on introducing speedwork into your routine. You should have an established base of at least 20 miles per week before incorporating these "quality runs" into your schedule. It's also best to have at least a year of running experience under your belt. The reason for both is that speedwork adds considerable strain to your muscles and connective tissues. Without the necessary mileage foundation, you may wind up injured rather than fast.As with all your runs, you should start and finish your specialized sessions with easy running, preferably longer than the typical ten or fifteen minutes you might do before your normal training run. With all of these workouts, you're pushing your body close to its limits, and it's unwise either to start or stop suddenly. Stretch well and give yourself 10 minutes of easy running, both before and after the workout.
Also keep in mind that it's important to keep moving between the "hard" portions of your workout. All of the workouts discussed here involve the alternation of hard and easy efforts. "Easy" means a slow pace, maybe a jog. But it does not mean walking, stopping, or collapsing to the track and wheezing. If you need to do any of those things, you're running the hard portion of the workout too fast. The old adage of "no pain, no gain" is simply wrong. The idea is to push only a little bit harder than your normal training pace to get the benefits; there will be some modest discomfort but certainly no pain. You should always have the energy after each interval to continue running slowly during the rest periods. By doing this, you keep your heart rate up, and as a result, you prevent blood from pooling in your legs. Keep running, even if slowly: it's good for you.
Ideally, you should run each of the hard portions of the workout at approximately the same pace per session. You should not feel exhausted by the end, but neither should you feel like you're still full of energy. This helps teach you the value of pacing yourself in a race by being aggressive but realistic in your starting pace.