How to Taper for a Marathon

Whether you love it or hate it, the marathon taper is a vital part of training. However, it can also be one of the trickest parts. Do too little, and you may feel stale and unfit; do too much, and you may be overly fatigued come race day. How long should you taper for a marathon – and what exactly should that taper look like?

The Science of the Marathon Taper

A 2007 meta-analysis (high-quality of evidence) published in Medicine and Science in Sports and Exercise examined multiple studies on tapering for swimmers, runners, and cyclists. For all three disciplines, a two-week taper produced the maximum desired response; a three-week taper saw a reduction in dose-response (meaning it was effective but less effective than a two-week taper). 

Why two weeks? The answer is complex (because the mechanism of why a taper works aren’t fully understood). The belief is that a two-week taper allows ample recovery and increases in muscle glycogen without losing aerobic or neuromuscular fitness (both of which render an athlete feeling “flat” on race day). 

Too much of a taper causes a detraining effect, which is the opposite of what you want before your marathon. 

In a two-week taper, mileage is 40-60% lower than it was at the peak of training. A marathon taper is a progressive taper, which means volume is gradually reduced. This typically looks like a 60% reduction two weeks out and then a 40-50% reduction (not counting the marathon itself) the week of the race. Ideally, this reduction comes from reducing the duration of each session, rather than altering the frequency of runs, which can leave an athlete feeling physically or mentally stale. 

Intensity will decrease in relation to volume, but it should not be significant reduced until race week. For example, if you did 30-40 minutes of volume at threshold three weeks out, you may do 20-25 minutes at threshold two weeks out. Intensity can be moderated by scaling rest intervals to allow for volume at intensity without requiring significant recovery. 

Based on research, a taper provides an average improvement of 2%. Two percent may not seem significant, but for a 3:30 marathoner, just a 2% improvement is a 3:26 finish time – a PR which many runners would be very happy with. 

With exercise science, the theory is only part of the equation. What does a marathon taper look like in actual practice? Let’s delve into it! 

Three Weeks Out:

Don’t get too excited about the taper just yet! This week is less about actually tapering and more about recovering from a big workout. The volume will reduce slightly, by approximately 85-90%. If you peaked at 50 miles per week, you will reduce to approximately 45 miles. Of that total decrease, some will come in the long run, which will decrease by about 80-90%. If your final long run was 20 miles, you will do 16-18 miles this week.

You also will do your final big workout this week, such as a long workout at marathon pace and/or a continuous tempo run at half marathon pace. 

Now, here’s a big caveat: if you previously responding poorly to past tapers, this week may not differ too much from your peak training. This still should not be your biggest intensity week, but you may maintain closer to 90-95% volume and only decrease intensity slightly. 

If you include strength training in your marathon programming, you want to begin to taper strength training as well. You should begin to decrease the number of sets and reps and slightly reduce the amount of weight used. 

Two Weeks Out:

In the 8-14 days out from the race, you will start to taper for the marathon. You will want to reduce volume by 60%. Intensity will reduce also. Workouts are less about building fitness and more about keeping aerobic systems functioning efficiently. Your long run (the last one before the race) will be drastically shorter, likely in the range of 10-12 miles (although you may do more or less depending on the time on feet). 

While you will naturally reduce intensity as volume decreases, you do not want to eliminate it completely. A hard workout should be specific to your race goals. For example, very short intervals would tax the wrong energy pathways too close to the marathon. Instead, a tempo run provides direct speed support for the marathon. Since you want to minimize strain, threshold intervals rather than a continuous tempo run are ideal.

Race Week:

If you have been doing strides or short 20-30 second surges in your runs, do not stop now. According to Steve Magness’s The Science of Running, you want to optimize your muscle tension with short 15-20 second strides. Strides will maintain that desirable “pop” in the legs but are too short to tax your anaerobic system. 

Finally, you want to do a race pace workout about four or five days out. You want to avoid traditional sharpening workouts (such as 400m repeats) that require anaerobic energy pathways and tax your fast-twitch muscles. A race week workout should be specific to the demands of the event. For the marathon, this is typically a short marathon pace workout.  A race pace workout will prime your neuromuscular system and remind you what race pace feels like one last time. 

If you typically run the day before your long run, you may want to do a shakeout run the day before the race. A shakeout run is very short – only about 10-15 minutes in duration. You want to keep it short so that you barely use any of your precious fuel sources. 

What If the Taper Doesn’t Work?

If you still feel fatigued and think you needed more rest before race day, you may have been overtrained. Overtraining can occur from doing too much in the three weeks out from a race. However, it is more likely to occur from weeks of too much volume and/or too much intensity throughout the whole training cycle. 

If you felt flat and detrained, you may want to consider trying slightly more intensity during the taper. This is not a license to completely ignore the taper, but just to be mindful of programming. For example, if you reduced the volume significantly two weeks out, you may find that slightly more benefits you in your next marathon taper.