10K Training Guide - Page 2
Therefore, Runner A can run at a faster pace longer before feeling the same amount of fatigue as Runner B. Running economy is influenced by biomechanics, the proportion of slow-twitch muscle fibers, body weight and the density of mitochondria, microscopic structures responsible for aerobic metabolism.
The emphasis of 10K training is on lactate threshold, VO2max and the ability to withstand a fast pace. However, whether you're training for a 10K or ultramarathon, it all starts with mileage. That's because endurance training stimulates many physiological, biochemical and molecular adaptations. All of these adaptations can be thought of as your body's attempt to cope with the demand placed on it by running every day. For example, endurance training stimulates more fuel (glycogen) to be stored in your muscles, increases the use of intramuscular fat at the same speed to spare glycogen, increases the size of the left ventricle of your heart so that it can pump more blood (and oxygen) with each beat, improves your blood vessels' oxygen-carrying capability by increasing the number of red blood cells and hemoglobin, and increases your muscles' capacity to use oxygen.
Lactate Threshold (LT) Runs
You can improve your LT by running at your current LT pace. Increasing your LT pace allows you to run faster before you fatigue, because it allows you to run faster before anaerobic metabolism begins to play a significant role. The benefit to being able to run aerobically at 7:00 pace compared to 7:30 pace is obvious.
With my athletes, I typically use three types of LT workouts:
- Continuous runs (2 to 5 miles) at LT pace;
- Intervals run at LT pace with short rest periods, such as 4 to 6 x 1 mile at LT pace with 1-minute rest; and
- Shorter intervals run at slightly faster than LT pace with very short rest periods, such as 2 sets of 4 x 1000 meters at 5 to 10 seconds per mile faster than LT pace with 45 seconds rest and two minutes rest between sets.
LT pace is about 10 to 15 seconds per mile slower than 5K race pace (or about 10K race pace) for runners slower than about 40 minutes for 10K (about 80- to 85-percent maximum heart rate). For highly trained and elite runners, the pace is about 25 to 30 seconds per mile slower than 5K race pace (or about 15 to 20 seconds per mile slower than 10K race pace, or about 90-percent maximum heart rate). Subjectively, these runs should feel comfortably hard. (Please see "Have a Heart," Training, Issue 53, August 2008 for information on determining your maximum heart rate.)
Long intervals (3 to 5 minutes) increase the heart's stroke volume and cardiac output, leading to an increase in VO2max. Research has shown that high-intensity training (95- to 100-percent VO2max) is the best way to improve it. Regardless of the length of the intervals you choose, you should run them at the speed at which VO2max occurs (referred to as the "velocity at VO2max," or vVO2max), which is approximately 3000-meter (or 2-mile) race pace for highly trained runners. If you run 3000 meters in longer than about 10 to 11 minutes, however, your vVO2max will be between mile and 3000-meter race pace. If using heart rate as a guide, you should come close to reaching your maximum heart rate by the end of each interval. You can also do hill repeats on a trail in place of intervals on the track to serve as a transition into more formal interval training.
While long intervals are the most potent for improving VO2max because you repeatedly reach and sustain VO2max during the work periods, short intervals (1 to 2 minutes) run at vVO2max can also improve VO2max, as long as you use short, active recovery periods to keep VO2 elevated throughout the workout. Short intervals run at mile race pace will help you address the anaerobic component of the 10K by increasing the number of enzymes involved in anaerobic metabolism and your ability to buffer the acidosis that results from high-intensity running.