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Re: No lactate threshold [jaretj] [ In reply to ]
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jaretj wrote:
Interesting that you quote Tim Noakes work here but you replied to me on Jan 28 as if he was a quack.

http://forum.slowtwitch.com/...ring=jaretj;#5418055

You jumped to the wrong conclusion there. I've consistently agreed with Noakes ideas about drinking to thirst and I think there is much in his central governor ideas.

I was alluding to the fact Noakes is contraversial and well known.

I most certainly do not think he is a quack. What is you opinion of him?

I like him and his book Waterlogged is a very good book..
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Re: No lactate threshold [jackmott] [ In reply to ]
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jackmott wrote:
I think the argument about lactate threshold is largely just semantics.
The lactate curve itself has no threshold point, but the inflection point of the curve corresponds with a threshold in the power duration curve.

Exponential curves have no inflection point...

ZONE3 - We Last Longer
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Re: No lactate threshold [Derf] [ In reply to ]
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Good post...biology is, after all, messy (at best). The trends and ranges over time while factoring for as many variables as possible- the problem is that many want a smoking gun absolute, and we lack the research and tech to identify one.

http://www.reathcon.com
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Re: No lactate threshold [Trev] [ In reply to ]
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Trev wrote:
There is NO lactate threshold
Okay, now we know that the muscles don’t go anaerobic during heavy exercise and lactate production is due to carbohydrate being burned to produce energy. This brings us to the topic of “lactate threshold”. Recall that the theory of lactate threshold was that at some exercise intensity blood lactate levels increase dramatically, i.e. crosses a threshold, due to anaerobic metabolism. We already know that lactate is being produced in increasing high amounts for reasons other than the muscles becoming “anaerobic”, but is lactate increasing after crossing some “threshold”? Again, the answer is no.

This is good to know. No more Z4/Z5 intervals for me since they aren't doing anything different than Z1/Z2.
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Re: No lactate threshold [Trev] [ In reply to ]
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Isn't this old news?

I read a couple of years ago that (to put it quite simply) lactate was a fueling source and it was excess hyrodgen ions or some other chemical imbalance which caused "the burn".

Going off of memory, here, so excuse any inaccuracies. Point being that this is pretty old, right?
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Re: No lactate threshold [InWyo] [ In reply to ]
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InWyo wrote:
Sounds about right from what I've read. Steve Magness (http://www.scienceofrunning.com/), has written on similar themes. He also notes that Vo2Max is a nearly useless measurement (which also seems about right). I think some of these variables have come about simply because they could be measured, and for some reason, physiological studies rarely actually measure the easiest and most meaningful variable (i.e. actual performance).

I really like that website. I've read a lot of Steve's stuff. Some very interesting things, there.
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Re: No lactate threshold [jackmott] [ In reply to ]
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jackmott wrote:
Trev wrote:

Define Functional Threshold Power.


I still use 60 minutes.
It is a nice spot within the 'about 60 minutes' window.

I use 50 minutes simply because most of our crits that are supposed to be 60 mins end up being around 50-55 mins and I like using normalized power from those.

Convenience and all.
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Re: No lactate threshold [Trev] [ In reply to ]
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Quote:
There is no lactate threshold

For those here who are mathematically inclined there is a recent article on cycling and Maximal Lactate Steady State. Here is the cite:

Hauser, T., et al. (2014). "Comparison of calculated and experimental power in maximal lactate-steady state during cycling." Theor Biol Med Model 11: 25.

and can be found here:

http://www.tbiomed.com/content/11/1/25

To indicate the problem of using the MLSS parameter or any other threshold estimate alone for training without any knowledge of what is behind it, here is a quote from the article

Indeed, Bleicher et al. [12] verified, that two different athletes, (soccer and track), had
exactly the same velocity for onset of blood lactate accumulation (OBLA) of 4.4 m/s,
yet the individual parameters of VO2max and VLamax were higher for the soccer player
when compared to the track athlete (VO2max : 70 vs. 63 ml/min/kg ; VLamax 0.93 vs.
0.65 mmol/l/s , respectively). That confirms, therefore that identical MLSS could be
originate by completely different combinations of VO2max - and VLamax values. Using
either VO2max , VLamax or BLC alone, it is not possible to explain differences of Power at MLSS
between two athletes or the effects of training on the MLSS. As such, it would be beneficial
to understand, how MLSS is controlled by glycolysis and oxidative phosphorylation
within the muscle cell.


It includes a bibliography relevant to the issue of thresholds.

Relevant to above quote, several years ago Sebastian Weber sent us information on some cyclists he was working with. Here is a chart that showed the same phenomena as the quote:



Other examples from Weber and his training organization in Germany (STAPS) are on our web page on cycling.

http://www.lactate.com/lactate_cycling.html

The title of one of the abstracts of an article on the STAPS site is (translated by Google)

VLamax, the maximum lactate formation rate - the secret of endurance performance


Food for thought when designing training programs.

---------------

Jerry Cosgrove

Sports Resource Group
http://www.lactate.com
https://twitter.com/@LactatedotCom
Last edited by: Jerryc: Apr 23, 15 7:54
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Re: No lactate threshold [pedalbiker] [ In reply to ]
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Quote:
that Vo2Max is a nearly useless measurement (which also seems about right)

Seems like a strange comment since VO2max is one of the two main drivers of the threshold and the more dominant of the two factors and the one to spend most of one's time training for.


---------

Jerry Cosgrove

Sports Resource Group
http://www.lactate.com
https://twitter.com/@LactatedotCom
Last edited by: Jerryc: Mar 29, 15 11:15
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Re: No lactate threshold [Jerryc] [ In reply to ]
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Jerryc wrote:
Hauser, T., et al. (2014). "Comparison of calculated and experimental power in maximal lactate-steady state during cycling." Theor Biol Med Model 11: 25.

and can be found here:

http://www.tbiomed.com/content/11/1/25

To indicate the problem of using the MLSS parameter or any other threshold estimate alone for training without any knowledge of what is behind it, here is a quote from the article

Indeed, Bleicher et al. [12] verified, that two different athletes, (soccer and track), had
exactly the same velocity for onset of blood lactate accumulation (OBLA) of 4.4 m/s,
yet the individual parameters of VO2max and VLamax were higher for the soccer player
when compared to the track athlete (VO2max : 70 vs. 63 ml/min/kg ; VLamax 0.93 vs.
0.65 mmol/l/s , respectively). That confirms, therefore that identical MLSS could be
originate by completely different combinations of VO2ma

Operative word here being "confirms":

https://www.academia.edu/...ol_1988_64_2622-2630

(and before that, http://www.ncbi.nlm.nih.gov/pubmed/6826403)
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Re: No lactate threshold [Andrew Coggan] [ In reply to ]
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Quote:
Operative word

I disagree. The operative word is "understand." From what was left out of the quote:

and VLamax values. Using either VO2max , VLamax or BLC alone, it is not possible to explain differences of Power at MLSS between two athletes or the effects of training on the MLSS. As such, it would be beneficial to understand, how MLSS is controlled by glycolysis and oxidative phosphorylation within the muscle cell.


Here is an answer which we believe best explains the process



From

http://www.lactate.com/lactate_threshold.html


---------------

Jerry Cosgrove

Sports Resource Group
http://www.lactate.com
https://twitter.com/@LactatedotCom
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Re: No lactate threshold [Rob] [ In reply to ]
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Research and tech are probably much, much, much closer than the day-to-day variability in performance.

We need a new human being. ;)

The question of who is right and who is wrong has seemed to me always too small to be worth a moment's thought, while the question of what is right and what is wrong has seemed all-important.

-Albert J. Nock
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Re: No lactate threshold [Jerryc] [ In reply to ]
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Jerryc wrote:
Quote:
Operative word

I disagree. The operative word is "understand."

It's been understood that muscular metabolic fitness (a.k.a. LT) and cardiovascular fitness (i.e., VO2max) are really two different things for a very long time.

Moreover, the regulation of metabolic responses at the muscular level have also long been well understood (which isn't to say that such knowledge isn't growing ever deeper).

As for your schematic, I find it overly simplistic (though probable reasonable when dealing with coaches and athletes, who don't need to know all the gory details).
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Re: No lactate threshold [Andrew Coggan] [ In reply to ]
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Quote:
It's been understood that muscular metabolic fitness (a.k.a. LT) and cardiovascular fitness (i.e., VO2max) are really two different things for a very long time.

No, it is not well understood. Also, the LT is the result of VO2max. When one thing is a function of the other, you cannot say they are really two different things. They are not independent. See the above diagram. Change VO2max in some way and the LT will change in the same direction. In other words LT = f(VO2max + other variables)

I am not sure what muscular metabolic fitness is. It is vague. LT as it is used in endurance sports is a measure of effort in the physical environment. It is watts, speed, or some other effort level. It certainly is not a measure of muscular metabolic fitness whatever that is. And VO2max in not just cardiovascular fitness. It varies by muscle group utilized in the different sports. So it is cellular dependent too.

The other main variable which affects LT is VLAmax and when the energy that is a result of these two factors is applied to a physical situation, economy becomes an important issue in the value of the measure for LT. For example stroke mechanics in swimming or cadence in cycling or rigging in rowing or running shoes and surface in running etc. For a triathlete the best way to improve the threshold in swimming is often better stroke mechanics. These are reflected in the above diagram.

The metabolic process is discussed in several of Mader's publications. The summary publication is

Mader, A. (2003). "Glycolysis and oxidative phosphorylation as a function of cytosolic phosphorylation state and power output of the muscle cell." European Journal of Applied Physiology 88(4-5): 317-338.


Quote:
Moreover, the regulation of metabolic responses at the muscular level have also long been well understood (which isn't to say that such knowledge isn't growing ever deeper)

I doubt that is true. I once asked Bruce Gladden, how does the muscle decide which process to use to make ATP and he said no one had a clue. They know what the processes are but just how much of each one is used in a given situation was still a mystery.

The model above is an attempt to get at that. Which is why the strength of the anaerobic system affects the percentage of VO2 max that can be used at any effort level and affects how ATP is re-synthesized.

Quote:
As for your schematic, I find it overly simplistic

It is discussed in detail at

http://www.lactate.com/lactate_threshold.html and on our triathlon site on the anaerobic capacity pages. There are four. Of course Mader's concepts are what is behind it.

--------------

Jerry Cosgrove

Sports Resource Group
http://www.lactate.com
https://twitter.com/@LactatedotCom
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Re: No lactate threshold [Trev] [ In reply to ]
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Trev wrote:
jackmott wrote:
Trev wrote:

There is no lactate threshold, there is no Functional Threshold Power.


Well, logically that doesn't even follow.


Define Functional Threshold Power. At what duration does it occur? 50 minutes? 70 minutes? 47 minutes? 30 minutes? 92% of 20 minute power? 95% of 20 minute power? 98% of 20 minute power?

Please explain exactly where on the power duration curve this 'threshold' occurs.

You are mistakenly thinking of FTP as being defined by a value on a mean maximal power duration power curve.

FTP is perhaps better thought of as a property of the curve, than being a specific point along it. It's a functional expression of underlying sustainable aerobic capability expressed in wattage terms. As such it's conceptual but a very useful concept because of the utility of power measurement.

Think of the MMP curve as being a function of a few (useful) conceptual things, with FTP being one of them, i.e.
MMP(t) = f(FTP, A, B), where A and B represent other useful functional expressions of underlying physiological capability that are sufficiently independent of FTP and each other.

Since the mean maximal power curve either side of about an hour is pretty flat, then seeking precision in terms of duration is not required in any case when using this method (i.e. maximal efforts of about an hour) as a means to estimate FTP. IOW don't confuse means to estimate/establish FTP with a definition of FTP.

Naturally, the further you move away from longer durations of about an hour and towards shorter ones, then then MMP expression becomes less dominated by the FTP term (i.e. the A and B terms start to play a greater role in defining the shape of the curve), although FTP is still a dominant factor down to short durations of a few minutes, which should not be surprising given the nature of energy contribution of the various metabolic pathways to maximal exercise over various durations.

http://www.cyclecoach.com
http://www.aerocoach.com.au
Last edited by: AlexS: Mar 29, 15 23:19
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Re: No lactate threshold [AlexS] [ In reply to ]
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AlexS wrote:
Trev wrote:
jackmott wrote:
Trev wrote:

There is no lactate threshold, there is no Functional Threshold Power.


Well, logically that doesn't even follow.


Define Functional Threshold Power. At what duration does it occur? 50 minutes? 70 minutes? 47 minutes? 30 minutes? 92% of 20 minute power? 95% of 20 minute power? 98% of 20 minute power?

Please explain exactly where on the power duration curve this 'threshold' occurs.

You are mistakenly thinking of FTP as being defined by a value on a mean maximal power duration power curve.

FTP is perhaps better thought of as a property of the curve, than being a specific point along it. It's a functional expression of underlying sustainable aerobic capability expressed in wattage terms. As such it's conceptual but a very useful concept because of the utility of power measurement.

Think of the MMP curve as being a function of a few (useful) conceptual things, with FTP being one of them, i.e.
MMP(t) = f(FTP, A, B), where A and B represent other useful functional expressions of underlying physiological capability that are sufficiently independent of FTP and each other.

Since the mean maximal power curve either side of about an hour is pretty flat, then seeking precision in terms of duration is not required in any case when using this method (i.e. maximal efforts of about an hour) as a means to estimate FTP. IOW don't confuse means to estimate/establish FTP with a definition of FTP.

Naturally, the further you move away from longer durations of about an hour and towards shorter ones, then then MMP expression becomes less dominated by the FTP term (i.e. the A and B terms start to play a greater role in defining the shape of the curve), although FTP is still a dominant factor down to short durations of a few minutes, which should not be surprising given the nature of energy contribution of the various metabolic pathways to maximal exercise over various durations.

I'd like to take this opportunity to publicly thank Alex and other intelligent individuals like him who have both the understanding and the patience to explain my ideas to people in ways that are often better than I can muster.

Anyone interested in such concepts would do well to pay close attention to what such smart folks have to say, and ignore the trolls who repeatedly try to make things seem "fuzzy" just to forward their own agendas.
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Re: No lactate threshold [AlexS] [ In reply to ]
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AlexS wrote:
Trev wrote:
jackmott wrote:
Trev wrote:

There is no lactate threshold, there is no Functional Threshold Power.


Well, logically that doesn't even follow.


Define Functional Threshold Power. At what duration does it occur? 50 minutes? 70 minutes? 47 minutes? 30 minutes? 92% of 20 minute power? 95% of 20 minute power? 98% of 20 minute power?

Please explain exactly where on the power duration curve this 'threshold' occurs.

You are mistakenly thinking of FTP as being defined by a value on a mean maximal power duration power curve.

FTP is perhaps better thought of as a property of the curve, than being a specific point along it. It's a functional expression of underlying sustainable aerobic capability expressed in wattage terms. As such it's conceptual but a very useful concept because of the utility of power measurement.

Think of the MMP curve as being a function of a few (useful) conceptual things, with FTP being one of them, i.e.
MMP(t) = f(FTP, A, B), where A and B represent other useful functional expressions of underlying physiological capability that are sufficiently independent of FTP and each other.

Since the mean maximal power curve either side of about an hour is pretty flat, then seeking precision in terms of duration is not required in any case when using this method (i.e. maximal efforts of about an hour) as a means to estimate FTP. IOW don't confuse means to estimate/establish FTP with a definition of FTP.

Naturally, the further you move away from longer durations of about an hour and towards shorter ones, then then MMP expression becomes less dominated by the FTP term (i.e. the A and B terms start to play a greater role in defining the shape of the curve), although FTP is still a dominant factor down to short durations of a few minutes, which should not be surprising given the nature of energy contribution of the various metabolic pathways to maximal exercise over various durations.

"You are mistakenly thinking of FTP as being defined by a value on a mean maximal power duration power curve. "

No I'm saying it can't be defined - I'm pointing out FTP is a vague, blurred, fuzzy concept and there is no threshold. It is variable, all over the place, different whenever you measure it, different indoors outdoors, TT bike road bike, changes with inertia, affected by fatigue, rest, climbing compared to flat etc etc.

"FTP is perhaps better thought of as a property of the curve, than being a specific point along it. It's a functional expression of underlying sustainable aerobic capability expressed in wattage terms. As such it's conceptual but a very useful concept because of the utility of power measurement. "

I agree FTP is not a specific point on the curve. It is no more than an imprecise concept.

"Think of the MMP curve as being a function of a few (useful) conceptual things, with FTP being one of them, i.e.
MMP(t) = f(FTP, A, B), where A and B represent other useful functional expressions of underlying physiological capability that are sufficiently independent of FTP and each other. "

I don't agree FTP is useful. The actual power one can sustain over defined durations is useful.


"Since the mean maximal power curve either side of about an hour is pretty flat, then seeking precision in terms of duration is not required in any case when using this method (i.e. maximal efforts of about an hour) as a means to estimate FTP. IOW don't confuse means to estimate/establish FTP with a definition of FTP. "

The mean maximal power curve is not flat.

"Naturally, the further you move away from longer durations of about an hour and towards shorter ones, then then MMP expression becomes less dominated by the FTP term (i.e. the A and B terms start to play a greater role in defining the shape of the curve), although FTP is still a dominant factor down to short durations of a few minutes, which should not be surprising given the nature of energy contribution of the various metabolic pathways to maximal exercise over various durations. "

The dominant factor is actual power over relevant durations.



(
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Re: No lactate threshold [Andrew Coggan] [ In reply to ]
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I read this over on timetriallingforum.

Very entertaining.

http://www.timetriallingforum.co.uk/....php?showtopic=98754




This is a cross-post from Wattage Groups by Nathan Townsend. I thought, in light of some postings on the forum thus far it would make for interesting reading:-


A 30min TT is closer to threshold than a 60min TT


Long winded rant here but with plenty of interesting up to date science. Continue only if you have an open mind and wish to learn and understand about how to train with power....

I'm not going to waste any time whatsoever arguing any of this with Andrew Coggan, but the evidence is clear, 60min for the average trained cyclist is too long and is thus an underestimate of the power at which a true non-steady state metabolism emerges (at a rate which is meaningful for training). Most people cannot maintain threshold power for that long. There is always human variability though so some of you will be able to maintain a true threshold for that long, but the average trained cyclist no.

So by all means do a 20min TT and then estimate your FTP which is itself is an underestimate of threshold and then pretend that when you do medium or long intervals slightly above this power that you are in fact depleting your "FRC". Whilst W' and W'balance are considered to be representative of mechanisms that contribute to peripheral muscle fatigue and there is plenty of evidence to support this, I don't know what FRC is supposed to represent because there is not a shred of science on this made up variable, but what the evidence does tell us is that it probably isn't related to peripheral muscle fatigue (see attached study by Thomas et al).

There are many studies using a wide variety of experimental techniques which lead to these conclusions. In particular, as mentioned in another thread, the fundamental nature of the VO2 slow component means that mammals cannot commence exercising at threshold power and expect to be able to maintain this power for 60min, because the VO2 slow component occurs earlier than this ie: you start to fatigue earlier. Thus, you must either commence at a power output BELOW threshold and then as you fatigue you reach a power which is sustainable for a longer duration, or you commence at threshold, then as you fatigue, you gradually drop the power so that you're always on your threshold. It should come as no surprise that this is exactly how both Brandle and Dennis paced their successful hour record attempts, and is a fairly typical power profile of 40km TTs.

Here are two very recent articles (ie: current April edition of ESSR) which provide commentary on the VO2sc and its relevance to human performance.....

The Critical Power Framework Provides Novel Insights Into Fatigue Mechanisms
http://journals.lww....es_Novel.1.aspx

In particular note the following statement "for many years the VO2 slow component was ignored tacitly because it did not fit with muscle energetics models". It looks pretty obvious that the good Dr Coggan continues to ignore the relevance of the VO2sc and is thus leading all of you down the garden path with this "FRC" non-scientific garbage.

Skeletal Muscle Fatigue and Decreased Efficiency: Two Sides of the Same Coin?
http://journals.lww....ciency__.3.aspx


Also, I've uploaded a very interesting study already known to this forum that contains strong evidence in favor of everything that I've written here on this topic over the past couple of years, yet nothing in favor of the broscience that Coggan continues to carry on with in his perpetual state of scientific denial and/or ignorance....


Central and Peripheral Fatigue in Male Cyclists after 4-, 20-, and 40-km Time Trials.
http://www.ncbi.nlm....pubmed/25051388

Look at the results carefully:

-Average time for 20km TT = 31min, 40km TT = 65min
-Mean (SD) power for 20km TT = 279 (22); 40km TT = 255 (21) W.

So on average about 24W difference there. That isn't quite meaningless is it?

-In the 20km TT the average RER is 0.96. How is this possible if a 30min effort is above threshold? It is not possible. If you are above threshold then the RER must be above 1.0. (I conducted many 30min TTs on elite cyclists, including Cadel Evans when I was a grad student in the AIS physiology lab in Canberra. Using gold standard metcart equipment, usually these elite cyclists could hold right on 1.0, but not once did I see a cyclist hold a higher RER than 1.01-1.02 nor did I ever see that value steadily increasing until the last 5min or so. If FTP is closer to a 60min max effort, then 30min must be above threshold. So why doesn't RER keep increasing even for elite performers? The answer is simple. a 30min TT is not above threshold, therefore approx 60min is lower than threshold and so Coggan is wrong).

-In the 4km TT the subjects achieve a significantly greater level of peripheral fatigue than either the 20km or 40km TT but there is NO DIFFERENCE between the 20km and 40km TT. If a 20km TT is above threshold, then by definition you must be depleting "FRC". If FRC is supposed to be conceptually equivalent to W', which itself is closely related to the mechanisms which underpin peripheral muscle fatigue (see above review by Grassi et al), then what we should see is a difference in the level of peripheral fatigue between the 20km and 40km TT, but there isn't. Why? because the 20km TT is not being performed above threshold and there is little or no difference in depletion of FRC/W' between the two. Ergo FRC/W' is not depleting any faster in the 20km TT than it is for the 40km TT which is impossible in reality (but only possible in Coggan's alternate reality).

-Look at the lactate values (not including the final end spurt values). According to an arbitrary definition of MLSS in the 20km TT the average subject would be above MLSS. Can ANYONE honestly look at that figure and say that lactate has not attained a near steady state but instead is continuously increasing?

-In both the 20km and 40km TT the magnitude of central fatigue is about the same, and in both cases it is greater than for the 4km TT. What this tells us is that over these longer durations such as 30-60min, a contributing factor as to why an average trained cyclist adopts a lower power than their true threshold, is because we experience an additional component of central fatigue that has less effect over shorter durations.


Overall, this study is highly revealing and informative. If we could do a follow up study then a good option would be to repeat the experimental techniques and on separate days do TTs over the following durations 10min, 15min, 20min, 25min and 30min. We know that by the time you arrive at 30min, the level of peripheral fatigue has dropped and central has increased. Even in the 20km and 40km TTs I suspect the level of peripheral fatigue becomes magnified in the last 5min or so as subjects raise the power above threshold and properly start depleting W'. So for example this could be controlled for by simply instructing the subject to maintain the power constant (at whatever it is over the predecing 5min or so) until the end.

------------------------

So there is a lot of criticism here, not of Andrew Coggan himself, but of his biased opinions and lack of scientific rigour. I do not have anything personal against him, but the fact is that the science does not agree with his belief that the original definition of FTP (as stated in his book TARWAPM ie: approx one hour max power) is equivalent to the true maximal intensity at which the physiological mechanisms underlying the threshold phenomenon occur at. The lay cycling world is being led astray due to an incorrect and corrupted presentation of the true science which continue to to be developed throughout the scientific literature. However since blogs and non-peer reviewed books such as TARWAPM are more easily accessible and understandable to the lay public than peer reviewed journals, the incorrect version becomes accepted as de facto evidence and people believe it.

Lastly, whether or not any of this makes a difference to the way people train is irrelevant. It might not make any difference whatsoever to many people, however it does make a difference to factual validity which some people might consider important. Personally I know that if I want to conduct intervals which develop a higher level of peripheral fatigue, then I cannot assume my FTP is the correct boundary. I choose a higher intensity and do my intervals above that. Numerous studies in the literature indicate somewhere in the range of a 20-30MMP is probably a good choice, longer if you are better trained.

Why people conduct a performance measure eg: a 20min TT, and then make some arbitrary correction factor which has an unknown level of error eg: 95% to estimate something which is an estimate of something else, none of which has a scrap of scientific scrutiny to validate the hypothesis, is beyond me. By all means, keep it for your PMC, but when it comes to planning interval training and knowing whether your threshold power has improved, throw that 95% correction factor out the window because you've already got the hard untouched raw data in your hands.


Don't expect me to reply to a continuous stream of ignorant denial because the science is there published in print. If people need further clarification then they should read the science because I'm too busy to spend all my days on this forum. Enjoy and good luck everyone with your training and racing.P
Last edited by: Trev: Mar 30, 15 12:42
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Post deleted by Andrew Coggan [ In reply to ]
Re: No lactate threshold [Trev] [ In reply to ]
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Begone, troll.
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Re: No lactate threshold [Trev] [ In reply to ]
Quote | Reply
Trev wrote:
"You are mistakenly thinking of FTP as being defined by a value on a mean maximal power duration power curve. "

No I'm saying it can't be defined - I'm pointing out FTP is a vague, blurred, fuzzy concept and there is no threshold. It is variable, all over the place, different whenever you measure it, different indoors outdoors, TT bike road bike, changes with inertia, affected by fatigue, rest, climbing compared to flat etc etc.
One's MMP at any duration is different whenever you measure it, different indoors outdoors, TT bike road bike, changes with inertia, affected by fatigue, rest, climbing compared to flat etc etc. ;)

You are now deliberately confusing measurement methods with an expression of underlying physiological capability. Stop your deliberate obfuscating, it's just trolling.

Trev wrote:
"FTP is perhaps better thought of as a property of the curve, than being a specific point along it. It's a functional expression of underlying sustainable aerobic capability expressed in wattage terms. As such it's conceptual but a very useful concept because of the utility of power measurement. "

I agree FTP is not a specific point on the curve.
Noted.

Trev wrote:
"Think of the MMP curve as being a function of a few (useful) conceptual things, with FTP being one of them, i.e.
MMP(t) = f(FTP, A, B), where A and B represent other useful functional expressions of underlying physiological capability that are sufficiently independent of FTP and each other. "

I don't agree FTP is useful. The actual power one can sustain over defined durations is useful.
Since FTP and a couple of other key underlying physiological attributes tells you the power one can sustain over defined durations (amongst other things), or can be derived from it, then by your own definition, FTP is useful.

Indeed FTP is more useful than the MMP curve alone because it provides insight into why the MMP curve is shaped the way it is. The MMP curve tells you what you did or possibly can do, and yes that's helpful/useful. Understanding the key underlying physiological attributes such as FTP is even more so, as it explains why the MMP curve is the way it is and arms one with this additional insight to tailor training that is individually appropriate.

Trev wrote:
"Since the mean maximal power curve either side of about an hour is pretty flat, then seeking precision in terms of duration is not required in any case when using this method (i.e. maximal efforts of about an hour) as a means to estimate FTP. IOW don't confuse means to estimate/establish FTP with a definition of FTP. "

The mean maximal power curve is not flat.
I didn't say it was.

I said it was pretty flat at durations of about an hour. And it is.

Trev wrote:
"Naturally, the further you move away from longer durations of about an hour and towards shorter ones, then then MMP expression becomes less dominated by the FTP term (i.e. the A and B terms start to play a greater role in defining the shape of the curve), although FTP is still a dominant factor down to short durations of a few minutes, which should not be surprising given the nature of energy contribution of the various metabolic pathways to maximal exercise over various durations. "

The dominant factor is actual power over relevant durations.
The dominant factors are the underlying physiological attributes and their relative contribution to power output.

By expressing those underlying physiological attributes in functional terms of energy and rate of energy output (i.e. power), then it provides significant utility for those using a power meter to track their training and performance.

There are of course other means to assess underlying physiological attributes (e.g. various lab tests), but they are only ever going to be occasional snapshots, and lose the significant utility power based measures and such functional expression of attributes provide us, such as constant monitoring, the ability to tailor according to what's happening now/recently, and using the entire data set of work for validation and reliability rather than an individual lab test XX weeks ago.

Without such insight into the underlying physiological attributes, then we are not particularly well informed about why our power over various durations is the way it is. Such insight is very useful for a variety of reasons. If you don't agree that it is, then you really shouldn't be giving out advice about athletic performance.

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http://www.aerocoach.com.au
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Re: No lactate threshold [Trev] [ In reply to ]
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Trev wrote:
I read this over on timetriallingforum.

This is a cross-post from Wattage Groups
So you've cross posted a cross post. How novel.

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http://www.aerocoach.com.au
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Re: No lactate threshold [AlexS] [ In reply to ]
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Think of the MMP curve as being a function of a few (useful) conceptual things, with FTP being one of them, i.e. MMP(t) = f(FTP, A, B), where A and B represent other useful functional expressions of underlying physiological capability that are sufficiently independent of FTP and each other.

You have MMP(t) = f(FTP, A,B). But FTP = f(A,B) so isn't the relationship best expressed as MMP(t) = f(A,B)

I am not sure what you specifically mean by A and B but the main things behind the MMP curve are the same things behind FTP. Actually, I can think of A, B, C, and D and there are probably others.

By the way I am in no way saying that the MMP curve is not useful. Just clarifying what determines it.


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Jerry Cosgrove

Sports Resource Group
http://www.lactate.com
https://twitter.com/@LactatedotCom
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Re: No lactate threshold [Jerryc] [ In reply to ]
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Jerryc wrote:
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Think of the MMP curve as being a function of a few (useful) conceptual things, with FTP being one of them, i.e. MMP(t) = f(FTP, A, B), where A and B represent other useful functional expressions of underlying physiological capability that are sufficiently independent of FTP and each other.


You have MMP(t) = f(FTP, A,B). But FTP = f(A,B) so isn't the relationship best expressed as MMP(t) = f(A,B)

I am not sure what you specifically mean by A and B but the main things behind the MMP curve are the same things behind FTP. Actually, I can think of A, B, C, and D and there are probably others.

By the way I am in no way saying that the MMP curve is not useful. Just clarifying what determines it.


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You can think of A and B as functional expressions of physiological capabilities other than those provided by sustainable aerobic metabolism, and as such they are not functions of FTP but are sufficiently independent of FTP.

Unless you think, for example, that the physiological factors underpinning one's peak/sprint power over a few seconds and those underpinning FTP are somehow related.

http://www.cyclecoach.com
http://www.aerocoach.com.au
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Re: No lactate threshold [AlexS] [ In reply to ]
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You can think of A and B as functional expressions of physiological capabilities other than those provided by sustainable aerobic metabolism, and as such they are not functions of FTP but are sufficiently independent of FTP.

Unless you think, for example, that the physiological factors underpinning one's peak/sprint power over a few seconds and those underpinning FTP are somehow related.

I look at A and B as internal metabolic processes. And they cause FTP which is an external measure of body movement. So I look at the MMP curve (an external measure of body movement) as a result of metabolic processes and several environmental factors including the actual movement of the body.

I will name the main metabolic processes: aerobic metabolism, glycolytic metabolism and creatine phosphate metabolism. So MMP = f ( aerobic metabolism, glycolytic metabolism and creatine phosphate metabolism plus environmental factors.)

At most points on the curve the creatine phosphate system has little effect but at all the rest of the points the other two metabolic systems are operating and very influential as well as the environmental factors.


FTP and these metabolic processes which are producing the energy are not independent. FTP is very dependent on these processes.

---------------

Jerry Cosgrove

Sports Resource Group
http://www.lactate.com
https://twitter.com/@LactatedotCom
Last edited by: Jerryc: Apr 23, 15 8:04
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