As an example, If your typical training pace on a controlled run of 6 to 7 miles is 8:30 per mile, run the pick-ups between 7:50 to 8:10 pace per mile in the beginning of a training cycle and have the recovery periods be roughly the same as your normal easy running pace (8:25 to 8:35 pace). This entire workout is 31 minutes in length, including the recovery.
Fast-forward 6 to 8 weeks. Now that your fitness is beginning to come around and you're feeling stronger, the physiological emphasis of your workouts can and should change as well. Using the same fartlek, run the pick-ups a bit more aggressively—roughly 10 to 15 seconds per mile quicker than you did previously.
However, be certain to pair the surges with recovery that is a bit easier—essentially placing more emphasis on the surges and less emphasis on the recovery. By doing so, you now place a greater emphasis on your body's ability to maintain rhythm during a race effort as well as increase power development with the faster and shorter segments (i.e., 3 minutes, 2 minutes, and 1-minute segments).
Workout #2: The Long Run
The weekly long run is a staple for most runners. From beginners to seasoned veterans, a run each week that is considerably longer than the others is an effective way to build aerobic strength and teach the body to use oxygen efficiently (not to mention strengthen connective tissue which can paradoxically reduce the risk of injury later during more intense training). When beginning a training cycle, the majority of your longer runs should be at a controlled, conversational pace—about 75 to 80 percent of your maximal heart rate.
As with the fartlek sessions, longer runs have the unique ability to work on a variety of physiological elements, not the least of which is one's gear changing abilities and overall aerobic power. After four to five weeks of introductory "ramp in" training, tweak your long runs by adding a simple 1-minute pick-up every eight to 10 minutes throughout the course of the long run.
These surges need not be intense in nature (for example, if you normally run your longer runs at 9:45 per mile, toss in a 1-minute pick-up at 9:15 to 9:30 pace before returning to your normal 9:45 rhythm). They have a natural way of teaching the body to engage different tissue and vary tempo (something few of us do during any of our runs let alone the longest runs). After just two to three weeks of these surges, you'll find yourself handling gear changes even within race efforts much more easily.