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Part II---------------------
So, if we find that our runner has little or no
evidence of a relationship between his/her race performances (especially
if this is so as the distance gets longer), we can be very sure the
problem is in his legs.
If you waded your way through the long
thread I referred you to above, you will realize that this means the
mitochondria, capillaries and aerobic enzymes your training should have
created in your leg muscles, did not happen. Whatever trainin
g you have done to this point has not been as
effective as it could have been. Usually, I have found, for two reasons
(as given above): 1. You don’t run enough mileage. 2. You train too
fast.
Way back in 1973, physiologist David Costill and his
coworkers introduced what they termed, the "fractional utilization" of
VO2max. Which really just means, how much of their VO2max can each runner
actually use in a distance event. The argument was made that those who
could use the greatest fraction (percent) of their VO2max stood every
chance of being among the faster runners. This "fractional utilization" we
now know is basically made up of a runner’s lactate threshold (LT) and
their particular economy.
As the authors state, "At all running
speeds above 70% VO2max, the faster runners were found to accumulate less
blood lactate than the slower runners at similar speeds and relative
percentages of their aerobic capacities. The findings suggest that
successful distance running is dependent on the economical utilization of
a highly developed aerobic capacity and the ability to employ a large
fraction of that capacity with minimal accumulation of lactic
acid."
Simply put, the more you can use of your maximum aerobic
potential in a race, the better you will perform.
As recently as
1997, this paper by Costill was cited by J.A. Hawley et al in a paper
aimed at enhancing endurance performance. As the authors state, "It
would appear that the fraction of VO2peak or power than an athlete can
sustain for prolonged periods is inversely related to the accumulation of
lactate in the working musculature." (more lactate = lower % VO2max that
can be sustained = stop sooner; less lactate = higher % VO2max = maintain
for longer). They go on, "For example, in well-trained endurance
athletes, there is little or no increase in blood (and presumably muscle)
lactate concentration until the work rate elicits close to 85% VO2peak.
Direct support for this comes from the data of Coetzer et al (1993) who
reported that black African distance runners had lower blood lactate
concentrations after submaximal (21km/hr) and maximal (24km/hr) exercise
compared with white runners, despite similar running economies. Elite
Kenyan distance runners have also been found to have lower lactate levels
than top Scandinavian distance runners during both submaximal and maximal
exercise."
Sooooo. Let’s sum all this up, it’s very
simple.
1. Better trained runners can maintain a higher percentage
of their VO2max (85% or higher) in a marathon than lesser trained
runners. 2. They can do so because their blood lactate AT ANY PACE or
any percentage of VO2max is lower than the blood lactate of less
well-trained runners (ie: they are not "tougher" and just somehow putting
up with more discomfort than the runners around them, they are actually
more "comfortable", under less lactate "stress", than all other runners at
the same pace/intensity).
This also agrees with a large amount of
sport science studies which show a very high correlation between the
lactate threshold and performance in distance events. The higher (faster)
the running pace at the LT, the faster the pace in distance
races.
Sjodin and Svedenhag (1985) in a review on the physiology of
marathon running agreed, "the ‘threshold’ is the single best predictor of
performance in long-distance running, including the marathon." Once again,
fast pace at LT = fast pace in a distance race.
As I repeatedly
stressed in my long earlier thread, the training to improve your VO2max
(essentially the stroke volume of your heart) is NOT the same training as
that required to raise your LT (increase capillaries, mitochondria and
aerobic enzymes in your muscles). The speeds required are totally
different. LT training is one case in which faster is NOT
better.
So. To go back to our hypothetical runner. After I find out
the PR’s of the runner who has approached me, (and assuming he/she has no
good relationship between performances), I lactate test him.
Now
don’t be concerned, I only bring this in here to explain exactly why our
young runner (and possibly yourself) cannot maintain a positive
relationship across performances. In short, his LT is weak. It will NOT be
necessary for you to undergo lactate testing to know how to proceed to
improve your own training and your LT.
You see, I know from his
poor race results that my new runner is building lactate long before he
should (which is why, as I have tried to explain above, there is NO
relationship). Remember, high lactate = poor long distance race
ability.
So, somewhere along the way as he increases his running
pace, his blood lactate is climbing (earlier than it should and at slower
paces than it should). I know this. His results are telling me this, even
before I test him. If I can determine when that happens, at what
pace/effort that is happening, I will then know exactly how to train him
to make the lactate at that pace begin to stay low, and not climb until he
runs at a faster pace. And then a faster pace... and a faster
pace...
Think of it like this. If your LT is low (at slow pace
relative to VO2max), you are "borrowing" from your anaerobic ability to
help your aerobic ability maintain the particular pace you are running at.
Like having an overdraft at the bank because you cannot live within your
monthly wage. But as the race distance gets longer, you cannot borrow more
and more, but can only borrow less and less. Until at the marathon, which
is 99% aerobic, you cannot borrow at all and your poor aerobic ability is
exposed and you are left wondering why the pace is so slow compared to
(eg) your 10k.
Now here I would have liked to explain the mechanics
of how to test, because although you will not need to be lactate tested,
the knowledge of how to do so will be important further down the line.
However, for you to understand it fully, you would need to see some
charts, which I am unable to post. Fortunately I am able to refer you to a
website that does a very good job of explaining the rationale and the
lactate testing procedure in a very clear manner. If you would genuinely
like to improve your training (and race performances), spend some time and
go and read the information on the linked site. It is only a single page
of text and charts (although there are other links that some of you might
like to explore, although doing so is not necessary). I expect to have to
refer to the knowledge the single page contains in later parts.
http://www.lactate.com/pitesbas.html
Final
summation: if you cannot maintain a good relationship across race
performances it is because your LT is not good enough (not a high enough
percentage of your personal VO2max). Your LT is dependent on adaptations
in your leg muscles caused by training. If you have a poor LT, your
adaptations have not occurred well enough (despite even years of
training). As will be better explained later, these adaptations are
intensity dependent (train too fast, they won’t happen).
My
apologies if this appears long-winded, but it is a long-held belief of
mine that runners train better if they understand WHY they are doing
such-and-such training.
To be continued...
Addendum To Part
IILet's look at some major
negative effects of "borrowing" from your anaerobic ability in a distance
event (anything from 5k upwards). (For those of you who do not think you
are doing this, just note that if you have a poor(er) pace relationship as
the distances increase, you are.)
1. When the muscle cells in your
legs build up too much acidity (caused by running anaerobically), those
cells shut down since the acidity inhibits enzymatic action and
contractibility in the cell and energy breakdown can no longer continue.
So, the more you are trying to stoke the boilers, pour on the speed, and
fire on all cylinders, the more some of those cylinders are shutting down.
This is not so if you use those self-same cells/fibres
aerobically.
2. Breaking a molecule of glucose down into energy
anaerobically is horrendously wasteful of fuel. It will result in fuel
economy the equivalent of "2 miles per gallon". Breaking that exact same
glucose molecule down into fuel aerobically results in "36 miles per
gallon". If you are going far enough (HM or marathon), you better be as
economical as possible and get as many miles as possible per gallon
because otherwise you are going to run out of fuel and crash long before
the finish line. Note that the muscle cells that are operating
anaerobically will be unable to access your huge store of fat as a fuel
(which would give you wayyy better than even 36 mpg). Fuel which would
ensure you get to the 20 mile mark and still find you can pour it
on.
Think of it like this. Put the smallest compact car you can
think of, and a Ferrari, side by side. Empty both fuel tanks, give both of
them one gallon of fuel and tell them to go as far as possible. Which is
gonna win?
Since your LT measures at what pace you change over from
aerobic to (increasingly more) anaerobically-fueled running, it is also a
measure of when you stop being economical and become more and more
uneconomical. So, we can also say that a low (poor) LT also means poor
fuel economy.
Many of you will be able to give examples of guys (I
know at least two) who can crank out 20 mile long runs at 6.00m/m and yet
not finish a marathon at that pace. Why? Because, due to their precise
fuel economy (or lack thereof) they cannot store enough CHO to get them
through the final 6.2 miles. Their fuel economy, and therefore their LT,
is too low.
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