Hills continued
Remember that the idea of hill work is to negotiate the hills efficiently, with as little disruption as possible to your rhythm. Think of yourself rolling over the hill, almost as if it isn't there. Concentrate on keeping your upper body relaxed, while you let your legs do the work. While you don't have to attack the hill, you should still work it and pour on some effort. On gradual inclines, try to run a bit faster than you had been running on the flat before the hill. On steeper inclines, concentrate on lifting your knees and pushing off hard with every step. This attention to your "vertical" motion is at least as important as your forward motion up the hill. The steeper the hill, the more you should lift your knee; on the steepest inclines try to lift your knees so high that your thighs reach horizontal. The strong push-off and high knee lifts will increase both your stride length and the range of motion in your hips: voila, you've increased your speed.

Even for very long hills (1500m or longer), try to maintain the exaggerated knee lifts. The benefits will make themselves known soon enough. The knee lifts, incidentally, are not easy. But even with the extra workout, your legs take less of a pounding running uphill than when running hard on the flat or downhills - you're not hitting the ground as hard.

As you reach the articles of each hill, focus on running all the way over the articles until your reach the flat, and pick up your regular running rhythm again. Use the flat or downhill on the other side for recovery. As always during the easy portion of any speedwork, keep running - even if at a gentle jog. Go carefully on the downills - they can dish out a nasty pounding, particularly to your quads. The best way to run downhills is to lean into them, to the point that you feel you're about to fall on your face. Try to get your legs turning over as fast as you can with short, quick strides. Not only does this help reduce the pounding on your legs, but it also helps you increase your stride frequency. With a little practice, you'll find yourself running down hills with less effort, less pounding, and more speed. Not a bad combination. Those just beginning hill workouts will likely find hills a struggle at first, but before long hills become more of a friendly challenge than a mortal enemy. The more you run hills, the more you'll find yourself adjusting to them automatically and your stride shifting to "hill mode" without any thought or effort. It's a useful edge in races.

Intervals
The track. While most elite runners get their start there, many of us came to running by way of local roads, sidewalks and forest paths. For the average runner, the track seems all too intimidating, almost scary. Fact is, though, that the track is not simply the domain of the elites. Any runner at any level can improve her performance with a little help from the 400-meter oval. This is what intervals are about.
Interval sessions are the most formal of speed workouts in that the distances and target paces are precisely fixed before you run. The idea is to run a series of relatively short repetitions over distances from 200m to 1600m, with rest periods of slower running in between. Because of their very nature, intervals involve a shorter period of effort than your usual run of, say, 45 minutes at a steady pace. This allows you to run much faster than you usually do, adapting your body to higher demands and your leg muscles to faster turnover. Over time, you become more physiologically efficient.

Because of the clearly measured distances, the track is an ideal place to do intervals, but some may find the never-changing scenery to be, well, maybe just a little dull. In that case, you should feel free to do your intervals on the road, using permanent landmarks to measure distance.
The various distances, as you might guess, are each best suited to runners with specific goals. The 200m run (1/2 lap) is best for short-distance training (5K and under) to improve speed. The 400m (one lap) helps improve overall conditioning at slower paces, and at faster paces is good final race preparation. The 800m (two laps) is used to develop speed when training for races 10K and under and to condition form and pace when training for longer races. Finally, the 1600 - 2000m is used most often to train for longer races, from 10K to marathon, to help improve pace judgement and overall conditioning.
[ For more on Intervals ]

Tempo Runs
This is hands-down the least complicated variety of speedwork. There are no distances to keep track of, no split times to remember, no hassles. All you have to do is run faster than your usual training pace, somewhere right around your 10K race pace. Unlike most speedwork which consists of relatively short bursts of high effort, tempo runs call for a single sustained effort. The result is that your body learns race economy: running at a fast pace for relatively long periods of time. Tempo runs will give your articles speed a boost, too. By running nearly at race pace, your body becomes accustomed to running close to its upper limit (though not exceeding it). In doing so, you actually increase that upper limit, and you become gradually faster.

After your usual warm-up routine, run at your easy training pace for at least ten minutes. Then pick up the pace. As mentioned above, this speed should be right around your 10K race pace (around 80%-85% of maximum heart rate, if you use an HRM). The time, distance and pace of your tempo run, as with all phases of your running, depends on you and your ability (not to mention your goals). For the distance you choose (5 and 8 km are popular tempo distances), find a pace that is not so fast that you cannot sustain it for the distance, but not so slow that you do not feel challenged toward the end. Tempo runs should be tough, but not impossible. Depending on how you feel on any given day, how much spring is in your legs, and how far you are running, your tempo pace may vary from session to session. That's fine. The consistency that counts is the pace within each session. Try to keep your speed level for the full length of each tempo run.
Don't worry too much about figuring out the exact distance of your tempo run. It's really not terribly important. 5 to 10 km is probably a good range. The one value of knowing how far you are running, though, is that you are able to gauge your improvement over time. Still, this is easily done by doing most of your tempo runs on the same route. You may not know the specific distance, but you can still compare your times for that same fixed route.

The Long Run [ see more on the long run ]
In your rush to build speed, don't forget the all-important long run. Especially for the distance runner but also for short-distance speedsters, the long run is the essential foundation for building and maintaining stamina. Don't give it short shrift.

Build a long run into your routine every other week (weekend mornings are perfect). Make the distance anywhere up to 150 percent of your regular midweek runs, and trot along at your normal training pace. If a 10 km run is de rigeur during the week, for example, then 15 km should be the upper limit of your long run. You have to build km's gradually and give your body a chance to adjust to the pounding of those extra km's. As long as you are not picking up your speedwork very suddenly at the same time, you should be able to add 2 - 3 km to your long run every two weeks. This may seem like a painfully slow rate of increase, but it's a lot less painful than the injury you might otherwise risk. Take it slow, it's better than being sidelined for several weeks.

As always, keep in mind the oft-repeated 10-percent rule. Your mileage should not increase more than 10 percent from week to week.