Fartlek>
It's true: fartlek is almost as fun to do as it is to say. "Fartlek" is Swedish for "speed play" and consists of bursts of speed in the middle of a training run. Essentially, it's an unstructured interval session, the track without the rules. Fartlek gets your legs used to a variety of paces and in the process gives you an enhanced awareness of your ability to keep up those paces at various distances.
After warming up, run at an easy training pace, throwing in bursts of speed for various distances throughout the run. Vary the speed and times of the speed sections, from as short as 15 seconds to as long as two or three minutes. Between these bursts, allow yourself enough recovery time to match roughly 2/3 of the effort time. The recovery pace, though, should be faster than the recovery jog you might do during intervals on the track; keep it moving at an easy training pace.
It's a good idea to pick out a landmark -- a tree or a fire hydrant or a bend in the path -- where a speed section will end before you start picking up the pace. In other words, you have to know how far you are running for each section. Because the idea is to keep up a constant pace until you reach that landmark, it is important to pace yourself at the beginning. Don't tear off so fast that you can't keep up the pace through the end of each speed section.
A fartlek session can be as easy or as difficult as you wish to make it. Use fartlek for anything from a light recovery run to a grueling workout. As always, however, start out easy. Your first fartlek sessions should contain distances and paces that you feel comfortable with and that you feel you can gradually increase in future sessions. A twenty to thirty-minute fartlek session should be adequate for most runners. There is very little reason for them to go as long as an hour.
Intervals>
The track. While most elite runners get their start there, the great majority of runners came to the sport by way of local roads, sidewalks and forest paths. For the average runner, the track seems all too intimidating, almost scary. Fact is, though, 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 220 yards to one mile, 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 220-yard run (1/2 lap, or 200 meters) is best for short-distance training (5K and under) to improve speed. The 440 (one lap, or 400 meters) helps improve overall conditioning at slower paces, and at faster paces is good final race preparation. The 880 (two laps, or 800 meters) 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 mile is used most often to train for longer races, from 10K to marathon, to help improve pace judgment and overall conditioning.
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 top 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 warmup 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 a heart rate monitor). The time, distance and pace of your tempo run, as with all phases of your running, depends on both your ability and your goals. For the distance you choose (3 and 5 miles 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. Three to six miles 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.
