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No lactate threshold
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There is no lactate threshold.

No lactate threshold. Interesting article which quotes that man Tim Noakes.

http://arcrsa.blogspot.co.uk/...ctate-threshold.html


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.


Lactate increases exponentially with increases in exercise intensity and does NOT exhibit a threshold. This being the case, why did exercise physiologists believe there was a lactate threshold? Going back to Prof. Noakes again:
“This mistaken conclusion resulted from at least 2 errors. First, too few blood samples were measured. For example, if only 4 blood samples had been drawn at running speeds of 10, 14, 16, and 20 km per hour, then a fictitious anaerobic threshold would have been identified at 15.5 km per hour. But measuring blood lactate concentrations repeatedly – for example every km per hour – shows that blood lactate concentrations rise exponentially without any evidence of a threshold phenomenon.”

“It is clear that the blood lactate concentrations do not show a clearly defined, abrupt threshold response during exercise of progressively increasing intensity. Rather, blood lactate concentrations begin to rise as soon as progressive exercise commences. However, at low intensities, the rate of the increase is so low that it is barely noticeable. Only when the exercise becomes more intense does the rise become apparent, which perhaps explains the erroneous impression that blood lactate concentrations increase abruptly when the lactate threshold is reached.”

“For these reasons, the term anaerobic threshold, lactate threshold, and lactate turnpoint are no longer justifiable”(4)


So, you see, there is not a lactate threshold. Lactate increases exponentially with increases in exercise intensity and exhibits no evidence of a “threshold”.


Lactate doesn’t cause fatigue – it helps prevent fatigue
You might say at this point that whether lactate is produced by anaerobic metabolism or not, or increases in a "threshold" manner or not is immaterial if increasing amounts of lactate cause fatigue. After all, it doesn't really matter how the level of lactate increases if lactate is the cause of fatigue. (Recall that it has long been believed by the running community that lactate causes fatigue.) It is this core belief that has caused runners to focus so intently on lactate threshold - lactate causes fatigue and the lactate threshold is the point where there is suddenly enough lactate in the body to cause fatigue to increase rapidly. There is no doubt that blood lactate levels increase with increasing exercise intensity. If lactate causes fatigue then it wouldn't matter if muscles become anaerobic or how lactate increases in the body - these points do not negate the idea that lactate causes fatigue. Lactate does increase with increasing exercise intensity and if it causes fatigue, then the other points are ancillary. Therefore, the most important question to ask is, Does lactate cause fatigue? Absolutely not!
"Lactate is a totally innocuous substance that, if infused into the bloodstream, has no noticeable effects."(5)


That's right - you could inject your muscles with lactate and you would experience NO additional fatigue because lactate does not cause fatigue.
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Re: No lactate threshold [Trev] [ In reply to ]
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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).
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Re: No lactate threshold [Trev] [ In reply to ]
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Re: No lactate threshold [InWyo] [ In reply to ]
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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.

Which is what people mean when they say lactate threshold.

People who talk about lactate threshold also don't imply that the lactate causes it. The lactate is just one signal that fatigue is coming.

But, yes I agree with your point that we focus a lot on what we happen to be able to measure. See - heart rate.




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).



Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter
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Re: No lactate threshold [Trev] [ In reply to ]
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Maybe this is why a lot of studies just use VT2 or percent of vo2max/HR, even though these measurements also seem a bit arbitrary.

Endurance coach | Physiotherapist (primary care) | Bikefitter | Swede
Last edited by: mortysct: Mar 27, 15 15:18
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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.

Which is what people mean when they say lactate threshold.

People who talk about lactate threshold also don't imply that the lactate causes it. The lactate is just one signal that fatigue is coming.

But, yes I agree with your point that we focus a lot on what we happen to be able to measure. See - heart rate.




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'd agree.
There may be no threshold, but there is a point that we can reliably tie to performance.

I talk a lot - Give it a listen: http://www.fasttalklabs.com/category/fast-talk
I also give Training Advice via http://www.ForeverEndurance.com

The above poster has eschewed traditional employment and is currently undertaking the ill-conceived task of launching his own hardgoods company. Statements are not made on behalf of nor reflective of anything in any manner... unless they're good, then they count.
http://www.AGNCYINNOVATION.com
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Re: No lactate threshold [Trev] [ In reply to ]
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Having a high heart rate doesn't cause fatigue either, but it's a pretty damn good indicator how close you are to your limit.

I'd agree with Jack in saying it's more of a semantical error than an error in our knowledge of physiology, and our ability to measure lactate is probably the cause of it being such a coined phrase. BUT I'd say that what causes fatigue and lactate production are pretty damn closely related. Using the current definition of LT as fitness indicator isn't going to create any false positives in terms of world class athletes. If your LT is happening around 600w you're still going to be a monster, if it's happening around 200w you're still going to have trouble breaking the hour record. It's not going to produce any false negatives either, because if you're not creating lactate you're going to have a whole mess of other issues hindering your performance.

NOT being able to create lactate is actually a pretty sucky disease called Mcardle's disease- but that's more of a symptom than the etiology of the disease.
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Re: No lactate threshold [Trev] [ In reply to ]
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There is NO lactate threshold

Depends on what you mean by a threshold. This graphic shows tests that have been repeated many times:



If you define the Lactate Threshold as the highest steady state effort level where lactate remains at roughly the same level, then one may look at it as a threshold. Something different happens after one passes through it.

For a discussion of the definitions of the lactate threshold see:

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

For a long discussion of the various definitions and concepts of thresholds see:

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

No serious person in years blames fatigue on lactate.

Actually if you measure lactate at several steady state effort levels, lactate will eventually start to rise above what is called a baseline and the values will lie on a straight line till it hits the maximal lactate steady state. Then the amount of lactate measured each time will depend on how long one takes between measurements. This is what gives the lactate curve its supposedly exponential shape. But this exponential shape is an artifact of how lactate is measured and the lactate curve is really a straight line below "threshold."

A couple references on the Maximal Lactate Steady State

Billat, V., et al. (2003). "The concept of maximal lactate steady state: a bridge between biochemistry, physiology and sport science." Sports Medicine 33(6): 407-426.

Beneke, R. (2003). "Maximal lactate steady state concentration (MLSS): experimental and modelling approaches." European Journal of Applied Physiology 88(4-5): 361-369.


---------

Jerry Cosgrove

Sports Resource Group
http://www.lactate.com
https://twitter.com/@LactatedotCom
Last edited by: Jerryc: Apr 23, 15 7:48
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Re: No lactate threshold [Trev] [ In reply to ]
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<yawn>
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Re: No lactate threshold [Andrew Coggan] [ In reply to ]
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Did you just pass the yawn threshold?

customerjon @gmail.com is where information happens.
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Re: No lactate threshold [Andrew Coggan] [ In reply to ]
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Andrew Coggan wrote:
<yawn>

Yes, nothing new. I saw George Brooks brief most of this in the 90s.

Simplify, Train, Live
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Re: No lactate threshold [Mike Prevost] [ In reply to ]
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Yep, old becomes new again...just give it time.

http://www.fuelforendurance.com
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Re: No lactate threshold [jmayo] [ In reply to ]
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jmayo wrote:
Yep, old becomes new again...just give it time.

True story. Fitness and training theory are very cyclical. At this point, it is rare something is new. Most of the time, people just figure out a clever way to repackage the same old info and market it to people who don't know better.

"Just don’t abandon everything you’ve ever learned because of something someone said on the internet." - Eric McGinnis
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Re: No lactate threshold [Mike Prevost] [ In reply to ]
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Mike Prevost wrote:
Andrew Coggan wrote:
<yawn>

Yes, nothing new. I saw George Brooks brief most of this in the 90s.

This was the 1st study that I recall reading that really raised the issue:

http://www.ncbi.nlm.nih.gov/pubmed/3597269

However, if you apply more sophisticated math you can still make a case for inflection points in the lactate-exercise intensity relationship:

http://www.ncbi.nlm.nih.gov/pubmed/8727572

Regardless, anybody in the field worth their salts realizes that the notions of "thresholds" are really just mental conveniences, i.e., that the underlying physiology isn't quite that simple, even though its handy to talk about it that way.
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Re: No lactate threshold [Andrew Coggan] [ In reply to ]
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However, if you apply more sophisticated math you can still make a case for inflection points in the lactate-exercise intensity relationship

The people at Cologne found that the rise in lactate above baseline is essentially a straight line until the MLSS. Each point in this range represents a steady state. After the maximal lactate steady state there are no more steady states for lactate in either the muscle or the blood. The curve above this point will depend on how fast it is rising in the muscles due to the individual athlete's metabolism and the actual measurement situations, how long it will be between stages and the increase in intensity between stages.

Here is what we have on the CD-ROM we distribute about this.


The effect of short rest - When the effort is long enough and the effort is below the maximum lactate steady state, there is little difference between the lactate readings from steps with short rest and those with long rest. Why? Because once the body reaches an equilibrium (long effort) no further lactate will accumulate if the effort is below the maximum lactate steady state. So whether the body starts from rest or from an elevated lactate level (as long as it's below the maximum lactate steady state) the lactate level will end up at the same equilibrium point if the effort is long enough.

However, once the effort is above the maximum lactate steady state a short rest will tend to accelerate the lactate accumulation. Why? Because the longer rest will return the body to a lower lactate level and complete rest will return the body to resting rates. Hence the step that starts with a higher lactate level (tests with short rest) will accumulate lactate much faster.




When lactate is measured with tests that have long rests and long efforts, the lactate curve is very close to a straight line once it starts to rise. It is not the exponential curve that is seen in most research studies using lactate testing. Thus, an estimate of lactate values from 2 or 3 efforts is valid if the efforts are long (over 5-6 minutes)and are below or close to the maximum lactate steady state. This means that a 2-3 speed test is an equally valid measure of aerobic endurance as a test with several measurements. A test with fewer steps is obviously more desirable if it is equally valid. It saves time and money and both are important for training athletes.

For any athlete, lactate levels above the maximum lactate steady state are affected substantially by two variables, the length of the effort and the rest between efforts. Thus, any test that extends too far above the lactate threshold is problematic. The meaning of a specific lactate value is ambiguous since it is a function of these two variables.

What is of high importance is the maximum lactate that can be produced by an athlete during a short all out effort when fully rested. This is because, if the test is done correctly, it reflects the maximum strength of the glycolytic or anaerobic system. However, it cannot be measured during a step test since the maximum lactate value in such a test is a function of several variables besides the strength of the glycolytic system.


A model of exercise metabolism was developed by Mader and his collegues at Cologne in the 1980's and is described in the published literature. This model is taught at Cologne and is being used for the training of elite athletes in swimming, running, cycling, rowing and triathlon.

---------

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:
The people at Cologne found that the rise in lactate above baseline is essentially a straight line until the MLSS.

Only if you restrict the range of intensities and/or use an exponential X axis. Indeed, even the graph you posted shows a non-linear response below OBLA.

Anyway, the notion of lactate threshold goes back a lot, lot farther than the 1980s...at least to "Owles point" in the 1930s. In part due to misunderstandings regarding exercise biochemistry, though, VO2max becames the primary "measure of a man" (or woman). It really wasn't until Ben Londeree's work in the 1970s and Peter Farrell's paper in 1981 that the pendulum began to swing back the other way (in the English language literature, anyway).
Last edited by: Andrew Coggan: Mar 28, 15 8:39
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Re: No lactate threshold [Andrew Coggan] [ In reply to ]
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Ben Londeree's work in the 1970s

Londeree coined the term, maximal steady state. I never did find the first use of Maximal Lactate Steady State.

Londeree, B. R. and S. A. Ames (1975). "Maximal steady state versus state of conditioning." European Journal of Applied Physiology and Occupational Physiology 34(4): 269-278.


We had a long talk with him one year at ACSM. He was interested in what was happening with lactate research.

Mader after he escaped from East Germany in the early 1970's increased the interest in lactate as a variable when he proposed his 4 mmol/l concept. He had tested his runners in East Germany and they all seemed to exhibit a threshold at 4 mmol/l. He developed the "zweistufigen" test or two speed lactate test. Some call it"zweistrichen."

Mader, A., et al. (1976). "Zur beurteilung der sportartspezifischen ausdauerleistungsfachigkeit im labor." Sportarzt Sportmedizin 4: 80-88; 109-112.



Ten years later he started investigating the effect of the anaerobic system on the threshold and published his ideas in

Mader, A. and H. Heck (1986). "A theory of the metabolic origin of "anaerobic threshold"." International Journal of Sports Medicine 7(Sup): S45-S65.


Thus, began the concept of VLa max or what some call anaerobic capacity and its interaction with aerobic capacity resulting in what is called the Maximal Lactate Steady State.

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Only if you restrict the range of intensities and/or use an exponential X axis.

Well, people who have done over 10,000 tests using lactate passed this linear relationship along to us. It is not something many would do unless they were meticulous and doing it as part of their dissertation. Here are couple more not perfect images from our website and not using an exponential axis.





By, the way thank you for the Cabrera reference. I wasn't aware of it.

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

Jerry Cosgrove

Sports Resource Group
http://www.lactate.com
https://twitter.com/@LactatedotCom
Last edited by: Jerryc: Mar 28, 15 11:51
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Re: No lactate threshold [Andrew Coggan] [ In reply to ]
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Andrew Coggan wrote:
Mike Prevost wrote:
Andrew Coggan wrote:
<yawn>

Yes, nothing new. I saw George Brooks brief most of this in the 90s.

This was the 1st study that I recall reading that really raised the issue:

http://www.ncbi.nlm.nih.gov/pubmed/3597269

However, if you apply more sophisticated math you can still make a case for inflection points in the lactate-exercise intensity relationship:

http://www.ncbi.nlm.nih.gov/pubmed/8727572

Regardless, anybody in the field worth their salts realizes that the notions of "thresholds" are really just mental conveniences, i.e., that the underlying physiology isn't quite that simple, even though its handy to talk about it that way.

Functional Mental Convenience Power!
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Re: No lactate threshold [Andrew Coggan] [ In reply to ]
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Andrew Coggan wrote:
<yawn>

"Average power during a 1 hour time trial, or functional threshold power (FTP), provides a logical basis for training levels since it correlates very highly with power at lactate threshold, the most important physiological determinant of endurance cycling performance, integrating VO2max, the percentage of it that can be sustained, and cycling efficiency (although, if you define LT as a 1 mmol/L increase in blood lactate over the baseline observed during low-intensity exercise, the corresponding wattage will be some 10-20% lower than FTP). "

You may yawn but you justify Functional Threshold Power by claiming it correlates highly with power at lactate threshold. ( see you quoted above).

There is no lactate threshold, there is no Functional Threshold Power.
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Re: No lactate threshold [Trev] [ In reply to ]
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Trev wrote:
There is no lactate threshold, there is no Functional Threshold Power.

Well, logically that doesn't even follow.



Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter
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Re: No lactate threshold [jackmott] [ In reply to ]
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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.
Last edited by: Trev: Mar 28, 15 15:32
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Re: No lactate threshold [Trev] [ In reply to ]
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I fail to see why you keep tilting at windmills.

Seriously, stop being so pedantic about this "issue" of yours. It's an obsession of yours that matters to exactly 1 person and leaves the rest of us with rolling our eyes. I don't know what "functional" means to you, but it screams "pragmatic" or "working" to me. Given physiology has plenty of day-to-day variability, it may well be a band between 50-70 minutes (given the fall-off in this region is small). Or, even simpler, it's about what you can hold for an hour. Not an exact number, because the confidence interval around that power number is large enough to envelop a decent amount of time.

The more you scream bloody murder about this, the more you're showing that you have no understanding of either math/statistics or the physiology involved.

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 [Trev] [ In reply to ]
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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
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Re: No lactate threshold [Trev] [ In reply to ]
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Trev wrote:
Define Functional Threshold Power.

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

Maybe you don't get why people even use these kinds of ideas, - it is to extract the idea of ones aerobic power vs the anaerobic power. Knowing how each contribute to your performance has useful meaning. 60 minute power is a quick way to get at your aerobic power. You can use more complex mathematical models of it like coggan does now, you can use 50 minutes, or 70 minutes if you want.

Wouldn't use 1 minute though.


I'm sorry that the fuzzyness bothers you, but that is how physiology is. I suggest a move into the field of number theory or computer science (But not floating point) if you don't like that.



Kat Hunter reports on the San Dimas Stage Race from inside the GC winning team
Aeroweenie.com -Compendium of Aero Data and Knowledge
Freelance sports & outdoors writer Kathryn Hunter
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Re: No lactate threshold [jackmott] [ In reply to ]
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jackmott wrote:
Trev wrote:
There is no lactate threshold, there is no Functional Threshold Power.

Well, logically that doesn't even follow.

You're right, it doesn't. OTOH, the notion of a power threshold power is really the same sort of mental convenience as the notion of a lactate threshold.
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