You have gotten some
good advice from several posters here. I agree that it isn't necessary to run longer than 20 miles in training, especially
for a first marathon, to produce a good marathon performance. I ran my first one in 3:47:30 following a 14-week training program
with a max LSD of 18 miles....and just one of those....when my 10k times were around 47 minutes. By the time my 10k times
came down to 43-44 minutes, my marathons were under 3:30 and my max training LSD's had increased to 22-24 miles.
It is true that LSD's
of longer than 20 miles can be beneficial both psychologically and physiologically. However, once you get past 15 miles, the
level of stress increases with every additional mile. Trying to go longer 20 miles can increase the risk of an injury that
could keep you from the starting line at Tupelo. I think LSDs longer
than 20 miles are better reserved for future marathon programs. After you get your first marathon under your belt and better
know how well you respond to the cumulative rigors of marathon training....remember, you still have over two months of hard
training ahead of you before marathon day....then you could consider LSDs of longer than 20 miles in future marathon programs.
That's the way a lot of running experts structure progressively challenging marathon training regimens. For instance, Bob
Glover calls for max LSDs of 18-20 miles for First Time and Novice Competitors; 20-22 miles for Basic and Advanced Competitors;
and 20-24 miles for Champion Competitors.
I agree strongly with
Birkierunner's comment that, instead of increasing your LSD beyond 20 miles, it can be more beneficial....and maybe less stressful....to
increase weekly mileage by 10-20% to the 50-60 mile range, although you might not want to do even that for your first marathon.
Mileage is often the most overlooked element of quality in a training program. It is at least as important as the number and
length of LSD's, if not more so. Birkierunner runs excellent marathon times without LSD's longer than 19.5 miles and with
weekly mileage up to 70 miles. Similarly, Alberto Salazar, who was arguably the best marathoner America has ever produced, never ran longer than 18 miles in training....but
he ran 150 mile weeks.
One way to add a few
miles to your weekly total is to do a midweek medium long run, if you aren't already doing so. It should be about 2/3 the
distance of your previous LSD, which would mean 12-14 miles a few days after an 18-20 mile LSD.
Like a couple of others,
I disagree strongly with the comment that the LSD should not be longer than 25% of weekly mileage. If that were the case,
many, if not most, marathoners would be running max LSD's of 10-15 miles, which would be ludicrous. And if you were to peak
at 45 miles, then your max LSD would be only 11.25 miles! Many running coaches recommend LSDs of significantly greater than
25% of weekly mileage. Glover’s first time marathon program calls for LSDs up to 50% of scheduled weekly mileage.
I don't think that you
are running your LSDs too fast. LSD (L) pace, which should be the same as easy (E) pace, should get you into the range of
65-70% VO2max or 70-75% HRmax. For most runners, that's 1-2 minutes/mile slower than 10k race pace. Glover specifically defines
L pace as 1.5 to 2 minutes slower than 10k race pace, which would be about 8:30-9:00 for your 10k time of 43:55 (7:04 pace).
Daniels calls for E/L pace of about 8:45 based on your 10k time. Some people assume that, when running coaches call for an
E/L pace of 1-2 minutes/mile slower than “race pace”, they are referring to the race distance for which you are
training. Actually, most training pace recommendations are based on 10k race pace, specifically, or a target training heart
A caveat to the above
comments about pace....weather, especially temperature, matters. Training paces, just like race paces, should be adjusted
for climatic changes to optimize the desired training benefit. If the 10k time that your training paces are based on was run
in excellent cool, dry conditions and you are training in hot, humid weather, then training paces should be adjusted accordingly.
Thus, if you ran your 10k time of 43:55 under cool, dry conditions, then 8:45/mile might be just a little too fast for training
in Mississippi in July and August. (I assume that’s where you are since you plan to run the Tupelo Marathon.) If you
would expect your 10k race time might be more like 45-46 minutes under hot, humid conditions, then you probably should add
15 seconds or so to your LSD pace.
I also agree that it
is beneficial to work a few miles at marathon pace into at least some LSDs. But, don't force them on days that simply are
not good ones....and we all have those days. The MP miles can come at the end of the LSD, which simulates a hard finish when
you are tired. Or they can be sprinkled throughout the run in the form of surges of a few minutes each, which gets you accustomed
to running MP at various levels of fatigue.
One thought concerning
your target marathon time. Your 10k time equates to a 3:25 marathon and your half marathon time to a 3:30 marathon. That makes
your target range of 3:30-3:45 just a little conservative, which is good for a first marathon. However, there are two variables
that might make it a lot less conservative....even optimistic.
(1) Again, the weather
variable. I grew up in Pascagoula, MS and know how oppressive
the weather can still be in Mississippi in September. If
your 10k and half marathon were run under hot, humid conditions, then your target marathon range looks good weatherwise, even
for a hot marathon day. However, if you ran the shorter races under favorable weather conditions and you have a hot, humid
marathon day (anything over 60 degrees and/or 50% humidity are unfavorable marathon conditions), then you probably should
adjust your target time and associated race plan, accordingly....maybe by as much as 30 sec/mile or more.
(2) The algorithms used in race calculators and tables are based on a ratio between two race
distances. For instance, most all use a ratio somewhere in the 4.6-4.7 range to equate 10k and marathon races. In using a
10k race to project a marathon time, the ratio assumes that the runner is “adequately trained” to run the predicted
time. Many runners find the projection to be optimistic. One variable that leads to actual marathon times falling short of
predictions is training mileage. All other variables being equal, the runner who averages 80 miles/week in training is more
likely to run the predicted time than one who averages 40 miles/week. In 1997 an old RWOL forumite named BrianW conducted
an extensive survey of actual ratios between 10k and marathon performances relative to weekly training mileage. The resultant
ratios, which ranged from 4.55 to 5.5, had a direct correlation to training mileage. The runners who experienced actual ratios
of 4.7 or less were running 70 miles/week or more. For 45 mpw runners, the ratio was around 5.0 and for 55 mpw runners it
was 4.75-4.85, both of which project considerably slower marathon times than do the race calculators and tables. If you are
interested in the details, you might want to check out two old posts of mine titled “Predicting A Marathon Time From
A 10k Race” and “Predicting A Marathon Time” which are archived under the Marathoning section of my Running Page.
One final comment. Whichever
training program you are using....and it sounds like it’s Higdon’s....believe in it and follow it as closely as
you can. Modify it only if you think it either is not challenging you sufficiently or is working you too hard. Some of the details of the program might differ from others, but the totality of it is designed to prepare
you to run a good first marathon.
Good luck at Tupelo!