Mistake #1: Dropping Mileage Too Much
As race day approaches, many runners significantly reduce their volume in the last 7-10 days before the competition. The conventional theory is that the legs need a rest from all the mileage to perform optimally. However, when we take a deeper look at what effect easy aerobic mileage has on the body, both from a recovery and fitness-building perspective, the fallacy of significantly dropping volume becomes apparent.
By design, easy running is supposed to help you recover. An easy run increases blood flow to the muscles specific to running, helping to clear out waste products and deliver fresh oxygen and nutrients. If your recovery runs during the hardest portion of your training cycle have enabled you to adequately recover between hard workouts, what would change the ten days before your race, when you’re not performing intense workouts? Nothing changes. Significantly reducing your mileage does not result in faster recovery or more rested legs if your current volume has allowed you to recover properly during training.
Furthermore, when we look the specific demands of long distance running, we clearly see a heavy reliance on aerobic respiration as a primary energy system:
Since the aerobic contribution to events longer than two miles is greater than 85 percent, significantly reducing the specific component of training that provides the most value to aerobic conditioning is flawed. To perform your best, you need to continue to train your aerobic system without producing fatigue.
What You Can Do
Instead of dropping your total training volume in the last 7-10 days before your race, keep your easy aerobic running at the same mileage as you are adapted to in training. Then, the last 3 days before the race, reduce your volume by 20 percent the third day, 30 percent the second day, and 50 percent the final day before the race. This will eliminate any possible fatigue, yet still allow you to maximize aerobic gains.
Caveat – If you’re tapering for a marathon, you can start reducing volume 5-6 days before the race. The primary difference here is carbohydrate and energy conservation, which doesn’t play a role in events shorter than the marathon.