Age and CTL/ATL Constants - Can you help?

Discussion in 'Power Training' started by Porkyboy, May 21, 2008.

  1. Porkyboy

    Porkyboy New Member

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    Hi

    In order to try to optimise my training and tapering I've been looking at the above and have started to experiment a bit in particular with a higher ATL constant in my PMC. I wonder whether you would be willing to share what settings work for you along with your age? :eek:

    This would help me get a feel for what seems to work well for what age groups, even though there is huge variation between individuals.

    I'm 49, I'm currently using a CTL constant of 42 and an ATL constant of 10.

    Thank you.

    PBUK
     
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  2. Fightin Boba

    Fightin Boba New Member

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    52 yo CTL 42 ATL 10
     
  3. acoggan

    acoggan Member

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    49, 42, and 10 for age, CTL time constant, and ATL time constant, respectively.
     
  4. Porkyboy

    Porkyboy New Member

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    Hi AC

    I downloaded a presentation you gave a while back. In it I seem to remember that you indicated that in your experience performances were generally at their best with a TSB of about 15. Could I ask if this is still your view on this and do you feel this holds true over a wide age range? Do you think an older athlete should aim for a higher or lower TSB than this when looking to hit a peak and has any work that you know of looked at this?

    Thanks.

    PBUK
     
  5. acoggan

    acoggan Member

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    On average, a CTL of +10 to +15 appears to results in the greatest probability of one establishing a personal best for power at durations <5 min. At longer durations (i.e., >10 min), things shift downward a bit, i.e., to +5 to +10 (see the copy of my Performance Manager presentation as hosted on www.trainwithpower.net for details). However, these values are calculated using an ATL time constant of 7 d, and the absolute value for TSB is dependent upon the magnitude of the ATL time constant (higher time constant = more damping of ATL = smaller swings in TSB). Moreover, there are individual differences to consider, i.e., some people recover more rapidly than others from a big "hit out" (and some of us don't seem to recover as well as we used to!!), such that the above values can only be considered general guidelines. The best suggestion I can make, then, is that you use the Performance Manager as a "retrospectrascope*" through which to view your past successes and failures, and try to figure out what works best for you.

    *TM, Alex Simmons, 2005 (or was it 2006?) :D
     
  6. cooljazz

    cooljazz New Member

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    AC, is there some rule of thumb you use to arrive at this? I'm 51 and curious.
    thanks!
    maybe i should go and view that seminar...
    -richard
     
  7. Alex Simmons

    Alex Simmons Member

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    "Retrospectascope" was coined as a term applicable to using the PMC in this manner by me in early 2006 when I was using the beta eweTSS sheets (forerunner to the Performance Manager) to plug in a previous season's data and have it simply smack me in the face as to what was going on with my own riding....

    I called it looking at your data through the "retrospectascope" - i.e. "so that's what I actually did, but if only I had....." Hindsight and all that.;)

    What Andy hasn't mentioned are trials in which the time constants were varied based on various criteria. In the end, he settled on a fixed TC but allow people to choose the absolute value (within sensible limits)

    See the tricky thing is, as you get fitter, you do tend to recover better....

    So just clone the PMC a couple of times, change the TCs and see which one, over time, best matches your actual and perceived performances.

    And while using the PMC planning approach* for tapers is pretty handy aid - it is also very important that the composition of your workouts during a taper be suitable.

    * that would be the "Prospectascope" -TM Alex Simmons,2008 :D
     
  8. Piotr

    Piotr New Member

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    TSB?
     
  9. Alex Simmons

    Alex Simmons Member

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    Yes, that's what Andy meant. As long as you have sufficient CTL as well.
     
  10. Alex Simmons

    Alex Simmons Member

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    BTW - speaking of the Prospect-a-Scope, here's what mine looks like:

    [​IMG]
     
  11. acoggan

    acoggan Member

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    The default values of 42 d and 7 d for the CTL and ATL time constants are based on a review of the scientific literature.

    My personal choice of 10 d for my ATL time constant is based on doing essentially as Alex suggested, i.e., trying different values to see which one did the best job overall of predicting/explaining my sensations/performance. This search was aided in part by the fact that I often do the exact same workout on the ergometer on Tuesdays and Thursdays, but am usually more fatigued on Tuesday due to the prior weekend's training. A slightly longer time constant than the default of 7 d does a better job of matching my TSB to this fact.
     
  12. Fightin Boba

    Fightin Boba New Member

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    Alluding to the possibility that the ATL constant could vary for an individual within a season, dependent on a number of potential factors, like:
    - composition of training load (perhaps a higher composition of L6 and L7 work lengthening one's ATL constant)
    - your relative CTL (as alluded to above)
    - cumulative seasonal training/racing fatigue

    I am not sure of the magnitude of such ATL constant swings. Not having pinned down either the magnitude of the variations, or the specific identifiable factors that impact my personal ATL constant, I have not attempted to arbitarily changed my ATL constant within a season. I am in set it and forget it mode until post-season analysis time.

    Has anyone played with this in the PMC?
     
  13. acoggan

    acoggan Member

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    I'm not sure if I understand precisely what you mean by "this", but I can say that at one point, I foisted upon Alex et al. a version of the original "eweTSS" spreadsheet that automatically varied the ATL time constant as a function of CTL. This was an attempt to incorporate the knowledge that as your training load increases, the cumulative fatigue tends to hang around longer. On the whole, though, this didn't make a discernable difference, so the idea was ultimately dropped.
     
  14. Fightin Boba

    Fightin Boba New Member

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    By "this", I mean changing one's ATL constant in anticipation/response to some of the variables that I listed in my previous post. For example, changing one's ATL constant just prior to entering a block of L5/L6 training.

    Good information. Just what I was asking about. What was the typical magnitude of ATL time constant change that was encountered in that prototype?
     
  15. Alex Simmons

    Alex Simmons Member

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    IIRC it was linearly proportional to CTL, something like 1/10th of CTL.

    As Andy said, the differences didn't seem to make much of an impact to the useability of the model (i.e. checking out the state of the forest) and so the fixed but user definable TCs were chosen. Indeed at one stage I thought I was using the fixed TC model when in fact I was using the variable TC model. I didn't even notice until one day I wanted to tinker "under the hood".

    I think it also highlights that the impulse-response model is fairly robust and not overly sensitive - as long as the measure of relative intensity is appropriately weighted. In that sense, the model Andy developed is highly convenient but I'm sure that variations on a theme would most likely work well too.
     
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