The most important thing to do between marathons that are just a few (4-6) weeks apart
is to recover from the first one. However, that doesn't mean that you shouldn't continue to train.
The training that you do during the few weeks between marathons isn't going to advance
you to another PR level. What propels you to another PR in such a short time is the development that comes from having raced
the first marathon. Many people consider running a marathon to be destructive in nature....and it is. However, if you look
beyond the short term destructive impact of a marathon, it is also constructive.
As we know, the body develops through cycles of stress and recovery.....overstress
yourself, then give it time to recover to a higher, stronger level. That's the basic concept behind the hard/easy method of
training to become fitter and stronger. Well, the hardest effort that most of us will ever exert is racing a marathon. Immediately
after your body has recovered from the overexertion, it should be stronger and more developed. The purpose of running a second
marathon then is to take advantage of that "development" before it begins to wane. "Training" during the 4-6 weeks between
them should be geared toward maintenance, not development, while the body recovers and repairs the destruction wrought by
the first marathon. Thus, training should be less intense than it was before the first marathon, but it shouldn't be all rest.
So, how much training should one do between marathons that are 4-6 weeks apart? Well,
it varies with the individual. Some people recover faster than others....and it is important to remember that recovery from
the first marathon is the paramount objective. I can suggest a general approach, but each person who chooses to run multiple
marathons from a single training cycle has to fine tune it to what works best for him/her.
I essentially like to run a reverse taper, reach a "peak" that is about 3/4 the peak
mileage and LSD distance that occurred before the first marathon, then taper again for the second one.
I use a 2-week taper. Thus when the marathons are four weeks apart, I can complete
a 2-week reverse taper, run a reduced LSD (18-20 miles) two weeks after the first marathon, then taper again. If they are
six weeks apart, then I can do the reverse taper; get two weeks of almost 75-90% of peak training, including two LSD's; and
repeat the 2-week taper.
If you use a 3-week taper, then six weeks between marathons permit a full reverse taper,
a reduced LSD (75% of peak) at the end of the third week, and a re-taper. With four weeks between marathons, then I would
suggest an abbreviated 2-week reverse taper followed by a shortened 2-week taper for the second marathon. In that case, the
"peak" midway between the marathons would probably be in the range of 50-65%, instead of 75%, of your peak before the first
I also think that "lite" speedwork should continue during the 4-6 weeks, at least after
the first week or two following the first marathon. Some threshold and VO2max interval workouts should be included. These
sessions shouldn't be as frequent or as intense as during the basic training program. And they should not be forced. If they
don't are a struggle instead of flowing relatively easily and smoothly, then I would abort them.
Midway between the two marathons is an excellent time to run a short distance (5-10k)
race. In fact, if the marathons are 5 or 6 weeks apart, it is possible to work in two short distance races. I did that in
the fall of 1985 when my two marathons were 5 weeks apart. I ran an 8k in near PR time a week after the first marathon, followed
by a 10k two weeks later and the second marathon two weeks after the 10k. I PR'd in both the 10k (42:04) and second marathon
(3:24:51). Obviously, such short distance races would replace a lot of the speedwork that you would do between marathons.
If you are interested in more detail on my thoughts on back-to-back marathons, see old posts of mine titled "Marathon Recovery",
"Back To Back Marathons", and Marathons 3-Weeks Apart" on the Marathoning section of my Running Page.