All About The TAPER

This weekend marks many marathoners’ final long run ahead of the Boston Marathon (and for those targeting races like Eugene, Big Sur, Flying Pig, etc. the taper is within sight). As a coach, I notice that athletes typically fall into two categories: those that love and appreciate the taper and those that simply hate it and the perceived physiological processes that occur within it ahead of race day. The taper can also be a significant source of insecurity, both for athletes and coaches. It can often take a few training cycles for the athlete and coach to get a feel for what works best for them. Fortunately, this topic has been fairly heavily studied since the 1980s or so, and we have data to at least guide us in our decision making process. It should be noted that a lot of the foundational research was performed on swimmers and then translated over to long distance runners, but in recent years, the results have been confirmed and replicated in marathon runners.

So first, let’s define what the taper is. The taper refers to a period, usually ranging from a week to three weeks (but can go up to 28 days), of reduced training load that serves to allow the athlete to recover from the cumulative stressors of the preceding training block (all of which are relative to the specific athlete and their abilities): high volume, high intensity, stacked on top of each other over the course of say, 12-20 weeks, leading into a goal marathon race. We as runners might think the taper only refers to us, but it’s a strategy that’s frequently employed across disciplines, including strength training, swimming, rowing, cycling, and triathlon.

What goes on at a physiological level during the taper? A meta-analysis performed by Bosqet et al (PMID 17762369) found that the taper induces hypervolemia (fluid overload) and enhanced red blood cell production, along with an increase in oxidative enzyme activity (including the enzyme that makes glycogen) – all of which point to a measured increase in VO2 max, which has long been used as a determinant/indicator of performance. They also found a range of 13-34% taper-induced increase in muscle glycogen content, both in men and women, which undoubtedly contributes to improved aerobic endurance.

There are a handful of components to the taper: training volume (i.e. weekly mileage) is the most common association, but frequency, intensity, pattern (for our purposes here, we’ll focus on progressive or step taper), and finally duration (probably the most hotly debated tenant) are all a part of the taper as well, so let’s walk through ‘em all.

First up, training volume. You can decrease the training volume by keeping the same number of days in place within the training week, by simply decreasing the volume of each session (i.e. Susan runs five days/week with two rest days. During her taper, she continues to run five days/week but the volume of each session is decreased) OR you can decrease the frequency (i.e. Joe runs 6 days/week with one rest day. During his taper, he cuts down to 4 days/week with three rest days). A study by Hickson and Rosenkoetter (PMID 7219129) found that it is possible to maintain the 20-25% maximum oxygen uptake (otherwise known as VO2 max and even more generically known here as fitness 😉) gained during a 10 week training block for the next 15 weeks of reduced training frequency; however, a study by Mujjika et al (PMID 12840640) discusses that this more so applies to moderately trained individuals (loosely defined as amateur athletes maintaining 30-50% of pretaper values) and that much higher training frequencies should be enforced for the highly trained, especially when the sport involves technique (the steeplechase is a good example here).

Next up is intensity, which is often woven into the pattern of the taper. A progressive pattern incorporates a decrease in training by 10-15% immediately, followed by gradual decreases with a lower-percentage reduction each day heading into competition. A step pattern involves a single reduction in training and then remains there heading into competition (i.e. a reduction in training by 50%; it holds at this same volume until race day). The landmark study on tapering, and specifically the optimal pattern, is by Banister et al from 1999 (PMID 10029340), as he and his team evaluated triathletes. They found that a progressive pattern is significantly superior to a step pattern and VO2 max also increased significantly in the final two weeks of the athletes’ progressive taper. In terms of intensity, it is widely accepted across the board that training load shouldn’t be reduced at the expense of training intensity because of its vital role in maintaining the training adaptations that were acquired during the prior training block. The key takeaway here: continue with speedwork, but within the context of lower overall volume.

And finally, the duration of the taper. I’ll spend the most time on this topic, as it seems to be the most commonly debated element. The previously mentioned meta-analysis done by Bosquet et al found a “dose-response relationship” between the duration of the taper and performance improvement, stating that a duration of 8-14 days tends to represent the borderline between the “positive influence of fatigue disappearance and the negative influence of detraining on performance.” They found that performance improvements could be expected following up to 28 day tapers, but that negative results were also experienced by some of the athletes. They noted that this wide range in duration directly correlates with physiological and/or psychological adaptation responses to reduced training. Some higher performing athletes also experiment with the use of something called “overload intervention” which basically refers to a down week (a form of tapering) followed by a super high training load with increased frequency and/or intensity, and Bosquet’s study noted that this also plays a role in the variability of taper duration and its effects.

Mujika underscored that the time frame that separates the benefits of a successful taper from the negative consequences of insufficient training is not clearly established. Kenitzer found that based on changes in blood lactate concentration and performance times, that a two week taper best represents the limit of recovery and compensation time before detraining became evident, although this was in a group of female swimmers.

Researchers (and Kubukely et al in particular) tend to agree that the optimum taper duration is influenced by previous training intensity and volume, with athletes training harder/longer requiring the full two weeks in order to recover from the training, while also maximizing the benefits of their training; conversely, those who reduce their amount of high-intensity training need a shorter taper to prevent loss of fitness.

Finally, and perhaps the most useful study I found in my perusing, is one from 2021 by Smyth et al (PMID 34651125) that specifically analyzed longer, disciplined tapers in recreational marathoners. Their study found that strict tapers (meaning, the reduction in volume is consistent and not random) were associated with better marathon performance than relaxed tapers (the reduction in volume is inconsistent leading into race day) and that longer tapers of up to 3 weeks were associated with better performance (superior marathon finish-time benefits) than shorter/minimal tapers. They also found that women runners were associated with greater finish-time benefits than men, for a given taper type (less than or equal to 3 weeks in duration). Their findings were consistent with the aforementioned research performed over the years in high level, professional athletes, underscoring the importance of maintaining specificity and intention within the taper, regardless of if your marathon time begins with a 6, 5, 4, 3 or 2.

And there you have it! There is a lot of data out there on tapering, but this is the general gist of what the world’s leading sports scientists have to say. As a coach myself, I think it’s very much worth being intentional with your taper and certainly not being haphazard with it or foregoing it all together. Something I like to focus on during the taper for all of my athletes, regardless of ability/fitness level, is to use the decrease in training volume to sharpen up mental and emotional fitness, almost inversely to the physical component. Quiet reading, visualization, and preparation for how the athlete is going to react during a low OR high point during the race is just as important to me as being sure they’re physically rested and ready to rock.

Happy tapering, my marathon folks!