I'd be very curious about DopeyBadger's take on the taper.
#1 - Do what your training plan tells you to. You chose that training plan for a reason, and the author wrote it in such a way for a reason. So follow through on the conclusion of what you've been following for the last several months.
With that out of the way, the taper is going to depend on the distance of the race, and the individual. Some highlights, the longer the race distance, the more the volume drops proceeding the race. With little exception, the taper should maintain intensity even though the volume of the plan is dropping.
-Both a 5k/10k require minimal tapering. Typically the volume does not change much, but potentially the last workout prior (3-4 days out) is going to be at a slightly lower volume or extended resting intervals. But since the 5k/10k are short (relatively speaking), it's easier to balance the current volume with being race ready. A taper for a 5k/10k is more about maintaining that sharpened sword.
-A HM taper is usually 2-3 weeks. The volume should fall some during the taper period, but does not need to be as aggressive of a volume drop as a marathon. The intensity of workouts should remain similar up until about 5-6 days from the race. The volume of the hard workouts should drop some with the last workout at a slightly lower volume or extended resting intervals. Depending on the person, some may benefit from strides on the day prior to the event. This has to do with the tightening of the hamstrings and whether the runner is predominately a Type 1 or Type 2 muscle fiber runner. The day before the HM should be no more than 60 min and no less than 20 min. There are some runners who find an off day proceeding the event is better, but that happens less often.
-Beginner marathon runners, or those who have done let's say four or less, should stick with a traditional 3 week taper. The taper should drop in volume each week from peak to something like ~85%, ~75%, and then during race week all the mileage during the week excluding the marathon itself should be between 40-60% of peak. The intensity should remain the same during the taper. The volume of the hard workouts should drop over time. A marathon is much more devastating to the mitochondria than the shorter distances, so we need ample time from the last true hard workout. A good rule of thumb is 10 days out in order to reap the benefits, but recover enough. A shorter intense workout can occur within 5-6 days of the marathon, but it just needs to be a taste compared to the previous hard workouts in the marathon training, and likely an easier workout than you would see at 5-6 days out from a HM. Again, the focus for the marathon should be on recovery more than another hard workout to maintain that sharpened sword. A proper marathon taper has been shown to improve performance by about 3-4%. For a 4:00 hr runner, that's 7-10 minutes of improvement. Depending on the person, some may benefit from strides on the day prior to the event. This has to do with the tightening of the hamstrings and whether the runner is predominately a Type 1 or Type 2 muscle fiber runner. The day before the M should be no more than 60 min and no less than 20 min. There are some runners who find an off day proceeding the event is better, but that happens less often.
-Veteran marathon runners will learn that a taper is not a one size fit all. While the large majority of runners will do best with a traditional 3-week taper, there is data to suggest that some runners excel on a 4-week or 2-week taper. So as you gain more experience and learn more about how your body responds to certain kinds of training, and how much recovery is needed before another run, etc, then you can tinker with the taper to illicit a potential higher gain in overall performance. There are some professional runners who have even found a strange 5-week taper system where they peak super early for the race, then drop volume WAY down, then do some normal training for the last 3 weeks to be their best taper methodology.
Keep in mind during the marathon taper that you are likely to feel sluggish. For most it happens about 4-14 days from the race. Your body is changing over to a mindset of repair/rebuild instead of making new gains. So what may have felt easier just 7-10 days ago, suddenly feels more difficult. This is a marathon taper trap. Do not try to chase that sharpened sword feeling. Your endurance is what you need and it takes far longer for that to truly fade away. If the taper is accurately aimed to race day, then about 1-2 days out from the race is when you're going to start to feel much much better. In fact, I know some runners who don't "feel good" until the morning of the marathon itself. So trust your cumulative training, and don't sabotage yourself late trying to chase one more hard workout in advance of the marathon.
The hard part about studying different marathon tapering dynamics is that it's hard to find research subjects for these studies. In a proper training macrocycle for a year, most runners should limit themselves to two maybe three marathons. So you're really limited on your attempt numbers in the span of say five years. That makes it difficult to find study subjects willing to try something "abnormal" from the traditional 3-week taper because you run the risk of losing that 3-4% performance gain. That's why more often than not, the research on tapers revolves around veteran marathon runners who are looking to squeeze that last ounce of juice from their potential.
