A common saying among veteran and elite marathoners is that “the marathon taper is harder than the training itself.” When you’ve achieved a level of fitness where you’re no longer worried about your ability to complete the long runs, high mileage and daunting workouts, the thought of not training and losing fitness during the marathon taper is scarier than any workout a coach can conjure up.

More importantly, the taper portion of a marathon segment is also the time when runners make the most costly mistakes. Whether it be too little running, getting off a normal routine, or getting too worked up, it’s easy to ruin months of training during what should an relatively easy three weeks of training.

In this article, I am going to outline the three most common tapering mistakes I encounter when working with marathon runners. While this isn’t an exhaustive list, it does represent some of the less obvious mistakes you might have read about in the past.

Three weeks before the race: Resting too much

The single biggest mistake I see in marathon tapers is that people over-taper in the last three weeks leading into the race. This leads to feeling flat and sluggish on race day and increases the chance that you’ll come down with some type of sickness as your metabolism and immune system crash due to the sudden change in activity and demands on the body.

One reason I’ve found athletes to want to drop their mileage and/or intensity too much is that they don’t immediately feel good after a couple of extra easy days or a rest day. Most runners expect immediate gratification and to suddenly feel a pep in their step with just a few easy days. Keep in mind that it can take up 10-12 days to full absorb and recover from a hard workout. So, if your last hard long run was just last weekend, don’t expect to feel fresh for at least another week.

How to avoid this mistake

Most runners will find that reducing mileage to 80-90% of max will provide a sufficient respite from the training load without leaving them flat or sluggish. For example, if your peak mileage was 60 miles, your mileage would drop to 48-54 miles for the week.

Likewise make sure you maintain some intensity throughout this week of training. While your hardest workouts are definitely behind you, it’s important not to step off the gas pedal right away. Usually, I recommend performing just one workout this week (mainly because I like to schedule the last hard long run the previous weekend and want to ensure recovery). Here is my favorite:

8 mile tempo – first 4 miles at marathon pace, second 4 miles as fast as you can (usually half marathon pace). This workout provides some practice with running at your goal marathon pace (which should feel pretty easy at this point in the training) and a chance to “blow out the tubes” and get in one more confidence boosting session. With mostly marathon paced workouts left for training, it can be good for the confidence to run quickly and finish strong and fast.

Two weeks before the race: Not running specific workouts

Perhaps the most detrimental marathon tapering mistake runners make is not keeping the workouts specific to the marathon in the last two weeks of the training cycle. For example, I often see runners try to do short, speed-oriented workouts to build confidence, make them feel faster, or because the thought of long workouts when they are supposed to be tapering scares them. I also find runners doing Yasso 800′s to serve as a final race pace predictor, which I think is a mistake.

The problem with this approach is two-fold. First, by performing a type of workout and using an energy system you haven’t been utilizing in the last four to six weeks, you actually fatigue your muscles more because your body isn’t conditioned to it. It would be the same feeling as performing a set of heavy squats when you haven’t lifted in 4-6 weeks.

Second, one of the most critical components to race day success is being able to execute your race plan and run the correct pace, especially at the start of the race. In the last two weeks, you should capitalize on the opportunity to practice marathon pace. Not only does this ensure you work the exact energy systems you need for race day, but it will provide that crucial, last minute pacing feedback you need to execute the perfect race plan.

How to avoid this mistake

I like to do two workouts in this week. The first is a longer, straight marathon paced run, usually 6-8 miles, depending on the normal weekly training volume. This workout usually occurs 10 days out from race day to ensure maximum recovery even though marathon pace should feel pretty moderate at this point. The second workout is a broken marathon paced run, usually 2 x 3 miles at marathon pace with 3 minute rest. Again, this workout will help you solidify race pace, but the 3 minute rest ensures that it’s not a hard effort.

Week of the race: Worried about gaining weight

The last week of marathon training is definitely the most difficult mentally. No matter how hard you’ve trained or how many miles you’ve run, you’re going to fear that you can’t run 26.2 miles, never mind 26.2 miles at your goal marathon pace. Trust me, even elites who averaged 150 miles per week and put in some crazy workouts have this fear (this guy).

However, a less obvious fear that almost all runners encounter is putting on weight during the final week of tapering.

All runners have been told that they need to load up on carbohydrates and build their glycogen stores as race day approaches. However, because you’re also significantly cutting your training volumes and intensities, this increased calorie intake is bound to pack on a few extra pounds or two.

It’s a conundrum, especially if you’ve been trying to lose weight the entire training cycle and because this is the time you want to feel light and nimble. As a result, it’s a battle to get the glycogen you need without feeling like a the marshmallow man. Typically, the desire to avoid weight gain wins the battle and glycogen stores don’t get maxed out.

How to avoid this mistake

First, remember that a little weight gain is ok. Not only should you be storing extra fluids, which will tip the scale, but a full gas tank is much more important than a few pounds on race day.

Second, my recommendation is to augment your eating eating habits so that you’re getting in the energy and calories you need without feeling stuffed.  Graze on healthy snacks, such as vegetables and high-quality carbohydrates (oatmeal and whole grains for example) throughout the day. Also, keep your meals to under 600-700 calories, especially in the last two days before the race. Grazing and keeping your main meals small will help ensure that the calories are stored as glycogen, not fat.

Here are two complimentary marathon taper nutrition articles:

6 Nutrition Tips for the Perfect Marathon Taper

Nutrition During the Marathon Taper

As your big race day approaches, consider these three tapering mistakes gleaned from years of coaching marathon runners and make sure you don’t fall victim to the same pitfalls in the last three weeks of your training plan.

A version of this post originally appeared at competitor.com

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