Fatigue Resistance

On the contrary that is exactly what training does. Improved metabolic capacity (ie. increased mitochondrial density and enzyme activity, etc, etc) enables higher percentage of VO2Max to be utilized which flattens your power profile (obviously forget about the first seconds). And since glycogen use is closely related to the intensity relative to LT/FTP increasing LT/FTP will enable you to go longer with same power.
Training that consumes glycogen will also increase the size of the stores to some extent which once again enables you to go longer.
It's possible that none of this enables you to go absolutely longer but you cannot really detach the intensity from the equation (if you go slow enough and have someone to feed you, you may continue until you fell asleep and that's not what you meant by fatigue resistance?)

I forgot the one exception: increased glycogen stores. That adaption obviously increases the total energy capacity of the glycolytic system and partly also the oxidative system. However, the other ones you mention, increased mitochondrial density and enzyme activity, increase the max power of the oxidative system not necessarily its ability to produce that power for longer duration, right?

By fatigue resistance I mean the one used in Training and Racing with a Power Meter. It's a measure of the rate at which maximal power drops off as duration increases, e.g. the difference between 20MP and 60MP.

Since the ability to maintain high power level is quite depended on availability of glycogen, don't you think that any means to spare glycogen during effort will enable to push further your fatigue?

If at the starting point (eg. your power profile) then relation of FTP to 5MMP is 0.75 (didn't check the actual numbers just out of my memory) and with years of endurance training gets that to eg. 0.85 (due to ability maintain higher fraction of VO2Max) isn't that exactly flattening the power profile? Of course the whole profile may lift upwards at the same time but the further you get in your bike training the more the improvements come from flattening the profile rather than moving it up.
This is because the adaptations of the "left" part of the curve are faster and are "maxed" out relatively fast while the right part (endurance) develops slower but doesn't cease that fast.

Yes I agree about glycogen stores, but that is only one part of fatigue. I don't think 90MP is lower than 20MP solely because of reduced gylcogen stores. Right? There's some other things going on that cause fatigue. What adaptations reduce the onset or effect of those other fatigue factors? Since fatigue seems to not be understood very well, maybe no one knows the answer to my question.

Another way to look at this is to look at the known adaptations that are stimulated by long L3 efforts compared to those stimulated by shorter L4 efforts. I'm going to refer to the Table 3.2 on page 49 on Training and Racing with a Power Meter 2nd edition. There are no adaptations listed for L3 efforts that aren't also listed for L4 efforts. If this was the whole picture, we would expect training solely in L4 to produce exactly the same effect as training solely in L3 (but maybe to a different magnitude), however I think this has been observed to be untrue. I suspect that all-L4-all-the-time will produce higher 20MP/90MP ratio than all-L3-all-the-time will, i,e. it will increase fatigue resistance. Am I off track?

By the way, what science is Table 3.2 based on, do you know? There are no references listed.

I have read that the lactate threshold is at a higher percentage of the heart rate maximum in trained athletes than with beginners.so you might not be able to ride longer but stay longer in the aerobic zone that can be maintained longer.

You tricked me to talk about glycogen stores with your question setting of "going longer". But the same increase in metabolic capacity (FTP) that spares the glycogen also enables you to utilize higher fraction of VO2Max (dominikk85 you are right in principle though heart rate has very little to do in this equation) thus flattening the power duration curve after first few minutes. Even the fatigue mechanisms are not exactly known the adaptation is: increased mitochondrial density, size and enzyme activity.

Here's some read for you related to fatigue: Models to Explain Fatigue during Prolonged Endurance Cycling

Related to the question about the table of adaptations
"we would expect training solely in L4 to produce exactly the same effect as training solely in L3 (but maybe to a different magnitude)"

that is quite much the point that the creator of the table has repeatedly highlighted and the bases for the Sweet Spot concept.

I don't know but I would guess that the lack of references on table are due to them being so elementary basics that no references are needed.

Quoted post said:

Originally Posted by frost [IMG]/img/forum/go_quote.gif[/IMG]

Related to the question about the table of adaptations
"we would expect training solely in L4 to produce exactly the same effect as training solely in L3 (but maybe to a different magnitude)"

that is quite much the point that the creator of the table has repeatedly highlighted and the bases for the Sweet Spot concept.

It sounds like you are saying that training in L3 will produce the same fatigue profile as training in L4. Do I understand you correctly?

If fatigue profile is an unfamiliar term, here is a reference:

http://www.peakscoachinggroup.com/FP.aspx

If you pick a midrange L3 intensity and cycle as long as you can the fatigue at the end can be quite much attributed to the depletion of glycogen stores while doing an FTP test it is not that simple what makes you stop.

However the adaptations (with a note that obviously almost in any training zone adaptations are not limited to the ones typically described eg. in mentioned table) for training in both zones are similar and those adaptations are also the ones that help you going longer or faster in both cases.

Or to put it simply: to better ride your bike just ride your bike : )

Quoted post said:

Originally Posted by frost [IMG]/img/forum/go_quote.gif[/IMG]

Here's some read for you related to fatigue: Models to Explain Fatigue during Prolonged Endurance Cycling

Many thanks for this! It has the depth I was looking for. Now I just have to find time to read the whole thing.

BTW what does L3 and L4 mean?

Quoted post said:

Originally Posted by dominikk85 [IMG]/img/forum/go_quote.gif[/IMG]

BTW what does L3 and L4 mean?

They are training zones.

L3 = "level 3", 'zone 3", tempo
L4 = "level 4", "zone 4", lactate threshold

http://home.trainingpeaks.com/articles/cycling/power-training-levels,-by-andrew-coggan.aspx

Quoted post said:

Originally Posted by gudujarlson [IMG]/img/forum/go_quote.gif[/IMG]

They are training zones.

L3 = "level 3", 'zone 3", tempo
L4 = "level 4", "zone 4", lactate threshold

http://home.trainingpeaks.com/articles/cycling/power-training-levels,-by-andrew-coggan.aspx

thank you. is there a simple test to find out my LT without a power meter or lactate blood testing? (just have heart rate, speed and cadence)

Quoted post said:

Originally Posted by dominikk85 [IMG]/img/forum/go_quote.gif[/IMG]

thank you. is there a simple test to find out my LT without a power meter or lactate blood testing? (just have heart rate, speed and cadence)

Strictly speaking Lactate Threshold is defined as intensity where blood lactate exceeds resting level with a fixed amount (1+1mmol/l). This intensity is typically somewhat less than TT intensity or Functional Threshold Power.

There are some protocols for testing "threshold heart rate" eg. average HR from an evenly paced longer TT or HR after certain time, using percentage of your max HR or using a percentage of HR range ((maxHR - restHR)*constant + restHR). You'll find lot of examples using google. However if you keep in mind, that in body there are really no thresholds, HR varies a lot regardless of actual intensity (eg. due fatigue, hydration, temperature, thermogenics like caffeine) and especially that exercising at certain narrow intensity is not a magic pill you'll do fine by just listening your body.

If you then move to power meter training then there is value to know your threshold power (FTP) with certain accuracy for eg. training volume management purposes.

Quoted post said:

Originally Posted by dominikk85 [IMG]/img/forum/go_quote.gif[/IMG]

thank you. is there a simple test to find out my LT without a power meter or lactate blood testing? (just have heart rate, speed and cadence)

You can't measure your lactate threshold outside the lab, but you can determine your lactate threshold heart rate (LTHR) with a heart rate monitor. You can then base your training zones off it.

http://www.trainingbible.com/joesblog/2009/11/quick-guide-to-setting-zones.html

As an aside, there is an interesting thread here that explores the effects of cadence on heart rate. What I took away from it is that heart rate at a given power depends on cadence, but heart rate at all cadences converge at the lactate threshold. This is something I have casually observed myself. LTHR is more reproducible than heart rate at other output powers.

https://groups.google.com/forum/?fromgroups=#!topic/wattage/73PBvZEioUQ

Quoted post said:

Originally Posted by gudujarlson [IMG]/img/forum/go_quote.gif[/IMG]

You can't measure your lactate threshold outside the lab, but you can determine your lactate threshold heart rate (LTHR) with a heart rate monitor. You can then base your training zones off it.

http://www.trainingbible.com/joesblog/2009/11/quick-guide-to-setting-zones.html

As an aside, there is an interesting thread here that explores the effects of cadence on heart rate. What I took away from it is that heart rate at a given power depends on cadence, but heart rate at all cadences converge at the lactate threshold. This is something I have casually observed myself. LTHR is more reproducible than heart rate at other output powers.

https://groups.google.com/forum/?fromgroups=#!topic/wattage/73PBvZEioUQ

the second link doesn't work for me. that thing asks me for a google account or something like that.

Quoted post said:

Originally Posted by frost [IMG]/img/forum/go_quote.gif[/IMG]

Since the ability to maintain high power level is quite depended on availability of glycogen, don't you think that any means to spare glycogen during effort will enable to push further your fatigue?

It may be that your assumption, "high power level is quite depended on availability of glycogen", is wrong.

I suspect that high power for a pro is much higher than for you. Dropping a pro's high power level down to your high power level most likely will have the pro using a different mix of fuels than you use at the same power level. If so your assumption is in doubt.

Quoted post said:

Originally Posted by An old Guy [IMG]/img/forum/go_quote.gif[/IMG]

It may be that your assumption, "high power level is quite depended on availability of glycogen", is wrong.

I suspect that high power for a pro is much higher than for you. Dropping a pro's high power level down to your high power level most likely will have the pro using a different mix of fuels than you use at the same power level. If so your assumption is in doubt.

With high power level I was obviously referring to an individual's power related to a threshold. Comparision between individuals in this context is not very meaningful don't you think?

Quoted post said:

Originally Posted by dominikk85 [IMG]/img/forum/go_quote.gif[/IMG]

the second link doesn't work for me. that thing asks me for a google account or something like that.

You usually need a Google account to read posts from Google Groups.

If you already have one, you'll need to sign in so you can read them.

Quoted post said:

Originally Posted by tomw1974 [IMG]/img/forum/go_quote.gif[/IMG]

You usually need a Google account to read posts from Google Groups.

If you already have one, you'll need to sign in so you can read them.

I have a google account now but they say I have to apply for that group or something. too much effort to read a thread🙂