velosprinter wrote:
First, my zone 4 is 83-86% of max. 86% being where I am at LT.
I have been told that 45 min to an hour is max. However, I have just
recently upgraded to cat3 and could use a bit more power at LT. Also,
most of my racing is crit and TT.


If you race enough you should be able to figure this out from analyzing
changes you are forced to make. Depending on where you are competing,
pay attention to real differences rather than those you assume will be
different. Some regions start to add distance for Cat 3 others don't
until 2/1/Pro. If you already figured that out and have the start of
what you know to be your new requirements, then my suggestion is to use
"titration" which means to add time and intensity in measured
increments while paying careful attention to how you tolerate it.
Moving too fast can make the difference between acceptable adaptation
(some improvement with little or not trade-offs) and over-training.
Since you have no "control" group for yourself you need to take extra
care since failure provides much less information about where you go
next than some measure of positive adaptation(s). IOW, go with small
increments and if there is any doubt, reduce those increments. It is
better to go slower and wait for your body to adapt than to fail (which
is defined not by race results but by only having negative changes to
your performance). If you need to race more conservatively than do that
until you start to feel aggressive again while competing. Remember that
many upgrading athletes who move up during this time of the season make
no changes to training because racing provides the changes your body
needs at this point. If that will work for you then you can just start
prep. for 2007 with those changes that you assess based on your results
in adapting this way.

To answer your specific question about time in specific zones, only you
can answer that after you make the changes as I have suggested. It may
go down because you may still be experiencing increasing efficiency to
your cardio-vascular system and for that reason it is ideal to measure
your loads with power, calculated with an device or by measuring
reduced times over specific courses (hills are more accurate and linear
in power requirements but are not always ideal) either for all of your
interval work or at least enough to track changes in what "zone 4" is
for you. The whole concept behind training by zones originally was
designed to allow you to keep your work loads the same according to HR
because continuous improvements hopefully means that each time you do
your workouts, you can use the same template and allow your CV
adaptations to be your guidelines for increasing intensity in a
structured way that is very easy to follow. The higher the intensity
and your overall fitness becomes makes this training concept less and
less useful. That is why measuring results via power directly or
through performance becomes more useful and at one point almost a
requirement. You might consider using at least one or two simulated
ITTs per month if you can't compete that frequently and use results
from those performances to keep your HR zones relevant for you.

Good luck, enjoy yourself.