As it was said on
the previous post:
In Medicine, if one does not know the consequences of knowing just a
part of the equation related to the problem we are facing it could be pretty
dangerous. People actually die. Regarding triathlon training is something
different, but our training could not have the expected results. VO2 max is a marker that tells us many things
about training but we should know the whole equation in order to possess useful
information. VO2 max could have
prognostic value if we know the whole equation. 8 sept.
2012 VO2 MAX AND TRIATHLON
I will start with a
short history regarding our experimentation with lactate. We started measuring lactate to our
triathletes and never found a lactate below 2mmols/liter before starting
training. We checked the system more
than twice looking for mistakes and accepted for a while that the value was two
as a baseline. Over the course of years,
we found out that the adolescents measured never had a full sleep and sometimes
were out at night. Oops! Sometimes
measuring baseline lactate helps to know that our athletes are not sleeping
well or not resting, whatever you want to believe. Lactate
was in closer relation to going out at night than the previous day training.
In our experience, recovery sleeping is more important than a hard training day
in itself. Good for lactate at baseline!
It is pertinent that
what it was mentioned on previous post regarding VO2 max is accurate for
lactate also. Lactate was announced in a previous post: 1 avr. 2012 TRIATHLON PHYSIOLOGY FOR DUMMIES AND THE TENDENCY TOWARD THE MEAN
When speaking about lactate, I have to show you a
different way of looking at it. Another language so we can see something
else helpful… In Medicine there are many monuments left for our heroes
and at the end it is difficult to see “the real.” Lactate is the most
effective transport of energy for our body in the “fight or flight” situation;
when the body has an emergency, lactate is produced. OUR BRAIN NEURONS
USE LACTATE AS THE ONLY FUEL to do our daily task. I assume that neurons use it
in general as the main fuel. So, lactate is “good.” We have to produce
lactate to get the neuro-fibers firing. Around 4millimols per liter of blood
allows us to finish an Olympic Distance Triathlon at our best pace. The
more tolerance we acquired to lactate the better we are. Here, it is
important to point out that sometimes the cybernetic equilibrium is lost and
lactate continues to increase without being used by neurons or other cells (not
in the case of Lance Armstrong as you will see below). Anecdotal, we
can say that even if we finish a marathon in “the sweet spot,” our lactate goes
up above 10. It means, we have a tolerance to lactate above 4.
Keeping
with the promise of speaking another language regarding lactate; the use of
lactate by neurons will give us the NEURON
THRESHOLD to use lactate. “Lactate
threshold” should be “neuronal threshold” as it has to do with the neurological
training mentioned before in a post. The
neurons force the muscles to produce lactate in order to continue their work
and stimulate brain neurons for the same matter.
29 mars 2012
Rate coding of muscle force
The force produced by a single motor unit is determined in part by the
number of muscle fibers in the unit. Another important determinant of force is
the frequency with which the muscle fibers are stimulated by their innervating
axon. The rate at which the nerve impulses arrive is known as the motor unit
firing rate and may vary from frequencies low enough to produce a series of
single twitch contractions to frequencies high enough to produce a fused
tetanic contraction. Generally, this allows a 2 to 4-fold change in force. In
general, the motor unit firing rate of each individual motor unit increases
with increasing muscular effort until a maximum rate is reached. This smooths
out the incremental force changes which would otherwise occur as each additional
unit was recruited.[9]…
Practicing cadence improves our “basic neurons” without searching to
recruit more muscle fibers. Improving
our “basic neurons” to be stronger is done by increasing “work load (weight).” The long distance work outs help with the neurological
practice. As long as one spins as one
trains, the neurological apparatus is subject to training without involving
much of the muscles. The fastest the
cadence, the better it is. So far, we
are away from the muscles. We are
talking about neurons which innervate muscles-using-fatty acids as fuel (“basic
neurons”). We train our neurons to fire
“fast.” The weight load makes the difference; as long as the
weight is light we train basically our neurons to fire fast. Once we increase the weight load we start
training the muscle as well as the neurons.
To train at the threshold means to keep the “lactate balance,” between production
and utilization around 4 for the majority of the mortals, by increasing work
load or cadence. There is a limit to the
utilization of lactate by neurons but the muscles continue to release it and
can go up to 14. The neurons stop and
you bonk. The neurons stop because they
fatigue, not because of the lactate. I read in www.pezcyclignews.com an article by Dr. Cheung, where he mentioned that the
single most important predictor for winners was increased tolerance to lactate
(paraphrasing). I will write on how to
improve it next time.
