Marathon Training Guide - Page 3
If you run more than about 40 miles per week, or if you run faster than about eight-minute mile pace, you can add two miles at a time to your long run. Keep adding miles until you reach 22 to 24 (or about 3 to 3 ½ hours, whichever comes first), and do your longest run two to three weeks before your marathon.
Lactate Threshold (LT) Runs
LT runs are also very important when preparing for the marathon. The longer the race you're training for, the more important it is to train your LT, because the closer the race pace will be to your LT pace and the more important it becomes to hold a hard pace for an extended time. And for a marathon, you need to extend the duration of your LT runs. To accommodate the increased duration, you can run a bit slower than LT pace (which I call tempo runs). Since optimal marathon pace is only about 15 to 20 seconds per mile slower than LT pace (with the difference in paces getting larger as performance level declines), the goal of marathon training is to raise your LT and to increase your ability to sustain as high of a percentage of your LT as possible.
If you're experienced with doing many long runs and want to give your marathon performance a boost, try inserting LT-paced running into some medium-long runs (12 to 16 miles). These LT/LSD (long slow distance) combo runs simulate the physiological and psychological fatigue of the marathon. Like long runs, they severely lower muscle glycogen, stimulating its synthesis and storage. You can include LT segments at the beginning, middle and/or end of the run.
Some examples are:
- 4 miles at LT pace + 8 miles easy;
- 5 miles easy + 3 miles at LT pace + 5 miles easy + 3 miles at LT pace;
- 10 miles easy + 4 miles at LT pace.
After you've done a number of these combo runs, try running faster than LT pace for the last mile or two of the final LT segment, which will sharpen you for the marathon. For example, run 9 miles easy + 4 miles at LT pace + 1 to 2 miles faster than LT pace. You may want to run the LT segments on a track, where you can closely monitor your pace. Because these workouts are very tough, alternate the long run with the LT/LSD combo run every other week, and after three or four weeks, don't do either run for one recovery week.