The Powermeter Thread

[Retro Trev]

Then by definition you are not fatigued.

Sorry?

Are you saying I'm not fatigued because I was able to complete the sessions at the planned power?

I was able to complete the sessions but at considerably more physiological / metabolic cost.

 

[CoachFergie]

Sorry?

Are you saying I'm not fatigued because I was able to complete the sessions at the planned power?

Yes. Kenney, W. Larry; Wilmore, Jack; Costill, David (2011-11-18). Physiology of Sport and Exercise, Fifth Edition (Kindle Locations 4988-4990). Human Kinetics. Kindle Edition.

We typically use the term fatigue to describe decrements in muscular performance with continued effort accompanied by general sensations of tiredness. An alternative definition is the inability to maintain the required power output to continue muscular work at a given intensity.

 

[Retro Trev]

If I did 4 rides in a day each of 20 minutes at FTP would the metabolic cost of the last session be the same as the first session?

By we I assume you mean you and other sports scientists?

Read up on the slow component of VO2.

 

[JayKosta]

If I did 4 rides in a day each of 20 minutes at FTP would the metabolic cost of the last session be the same as the first session?

----------
What do you mean by 'metabolic cost'? Calories used? Blood chemistry changes?, etc.
And do you mean that each of the 4 rides is done at the same Power level?

When you say 'FTP', do you mean the greatest power level that can be achieved for 20 minutes when done at a physical condition that is well-rested, well-nurished, etc.
If the above is your definition of FTP, then I doubt that you could actually accomplish 4 such 20 minutes rides in a day.

Jay Kosta
Endwell NY USA

 

[Retro Trev]

----------
What do you mean by 'metabolic cost'? Calories used? Blood chemistry changes?, etc.
And do you mean that each of the 4 rides is done at the same Power level?

When you say 'FTP', do you mean the greatest power level that can be achieved for 20 minutes when done at a physical condition that is well-rested, well-nurished, etc.
If the above is your definition of FTP, then I doubt that you could actually accomplish 4 such 20 minutes rides in a day.

Jay Kosta
Endwell NY USA

FTP as the accepted max power you can hold for 60 minutes. And I can do 4 sessions of 20 minutes at FTP in a day. And yes all 4 at the same power level.

I can not do 4 sessions at my maximum average 20 minute power in a day. Can't do more than one and I can only do that when well rested.

 

[JayKosta]

FTP as the accepted max power you can hold for 60 minutes. And I can do 4 sessions of 20 minutes at FTP in a day. And yes all 4 at the same power level.
...

------------------
Do you know if your 'minimum recovery period' between sessions is the same, or if it gets longer for later sessions?
If it gets longer for successive sessions, that would indicate that some aspect of the 'metabolic cost' of the session also increases.

Jay Kosta
Endwell NY USA

 

[FrankDay]

At risk of going off topic, and I have not reviewed these to specifically look for injury rates etc:
http://www.ncbi.nlm.nih.gov/pubmed/10081053
http://www.ncbi.nlm.nih.gov/pubmed/11388717
http://www.ncbi.nlm.nih.gov/pubmed/16144585
http://www.ncbi.nlm.nih.gov/pubmed/18063715
http://www.ncbi.nlm.nih.gov/pubmed/20086406
http://www.ncbi.nlm.nih.gov/pubmed/2011683
http://www.ncbi.nlm.nih.gov/pubmed/21615188
http://www.ncbi.nlm.nih.gov/pubmed/23147089

etc etc

For further discussion if people are interested, I suggest a new thread or finding an old relevant one.

Most of those studies are pretty useless to this issue. There is one sentence in a study looking at saddle height that pretty much sums up the problem with all the studies:

The main limitations from the reported studies are that different methods have been employed for determining saddle height, small sample sizes have been used, cyclists with low levels of expertise have mostly been evaluated and different outcome variables have been measured. Given that the occurrence of overuse knee joint pain is 50% in cyclists, future studies may focus on how saddle height can be optimized to improve cycling performance and reduce knee joint forces to reduce lower limb injury risk.

 

[FrankDay]

------------------
Do you know if your 'minimum recovery period' between sessions is the same, or if it gets longer for later sessions?
If it gets longer for successive sessions, that would indicate that some aspect of the 'metabolic cost' of the session also increases.

Jay Kosta
Endwell NY USA

How does one assess the "minimum recovery period" between sessions? Or, how does one know the "optimum recovery period"? I think all one can say from this data is the rider had an "adequate recovery period" between sessions that allowed him to complete them all at his target power.

 

[FrankDay]

----------
What do you mean by 'metabolic cost'? Calories used? Blood chemistry changes?, etc.
And do you mean that each of the 4 rides is done at the same Power level?

When you say 'FTP', do you mean the greatest power level that can be achieved for 20 minutes when done at a physical condition that is well-rested, well-nurished, etc.
If the above is your definition of FTP, then I doubt that you could actually accomplish 4 such 20 minutes rides in a day.

Jay Kosta
Endwell NY USA

I suspect he is referring to his observation that it takes a higher heart rate and perceived exertion to complete the last session than the first, even though power is unchanged. This would suggest to me a drop in efficiency for some reason either because of muscle fatigue or a change in pedaling dynamic to a less efficient pattern as one gets tired. A second generation power meter should be useful in answering that question as to what is going on.

 

[FrankDay]

Then by definition you are not fatigued.

LOL. I was going to ask you "by whose definition" until you posted your clarification. From your "clarification" of this remark it is clear that your definition is only one of, at least, two and not even the one accepted by most scientists but included as an alternative definition in a single work.

We typically use the term fatigue to describe decrements in muscular performance with continued effort accompanied by general sensations of tiredness. An alternative definition is the inability to maintain the required power output to continue muscular work at a given intensity.

Not to be nit-picky or anything but a term can only have one definition if scientists expect to be able to have discussions about findings and understand each other. If one wants to have an "alternative definition" one should coin an "alternative term" for that definition or describe exactly what they mean. We all get frustrated by Dr. Coggan holding to the scientific definition of strength in these lay discussions when people discuss "strength" in the way most lay people think of it. Fatigue has a specific definition (a decrease in the ability to generate force with use) so what this rider is experiencing is probably fatigue related, in that his muscles have lost some ability to generate force over these sessions such that to maintain his set power he must work at a higher % of the muscles power towards the end than at the beginning to maintain his goal power. As a result he perceives himself as working harder and "being tired" and, probably, is seeing a higher HR also.

 

[CoachFergie]

The Angry Asian has ruffled a few feathers with this article...

AngryAsian: Consistency trumps accuracy for power meters

This comment from the RATWAPM Facebook Page...

Training and Racing with a Power Meter
Somebody needs to explain to James Huang that 1) with electronic scientific instruments, accuracy and precision (what he calls consistency) tend to go hand-in-hand (as they both reflect the choice of the underlying principle of measurement as well as the quality of the instrumentation), 2) if an instrument is precise, all you need to do to achieve accuracy is calibrate it, and 3) accuracy is in-and-of-itself important for numerous reasons, one of which is the need to be able to compare data *across* powermeters (e.g., if one breaks and must be replaced, if you have multiple such devices, if you wish to compare your abilities to absolute standards, etc.).

 

[Alex Simmons/RST]

The Angry Asian has ruffled a few feathers with this article...

AngryAsian: Consistency trumps accuracy for power meters

This comment from the RATWAPM Facebook Page...

lol. I placed a comment on that item earlier today.

 

[Retro Trev]

LOL. I was going to ask you "by whose definition" until you posted your clarification. From your "clarification" of this remark it is clear that your definition is only one of, at least, two and not even the one accepted by most scientists but included as an alternative definition in a single work.
Not to be nit-picky or anything but a term can only have one definition if scientists expect to be able to have discussions about findings and understand each other. If one wants to have an "alternative definition" one should coin an "alternative term" for that definition or describe exactly what they mean. We all get frustrated by Dr. Coggan holding to the scientific definition of strength in these lay discussions when people discuss "strength" in the way most lay people think of it. Fatigue has a specific definition (a decrease in the ability to generate force with use) so what this rider is experiencing is probably fatigue related, in that his muscles have lost some ability to generate force over these sessions such that to maintain his set power he must work at a higher % of the muscles power towards the end than at the beginning to maintain his goal power. As a result he perceives himself as working harder and "being tired" and, probably, is seeing a higher HR also.

I was using the trem 'fatigue' in the same way Dr Coggan refers to it. I was not using it in the terms of fatigue only ocurring at the instant one is unable to maintain the stipulated power.

I read this below recently - this is the type of fatigue I was referring to.

http://www.pponline.co.uk/encyc/the-slow-component-of-vo2-understand-it-to-go-faster-39797

My question is this,

I did a 20 minute max test on Sunday when fully rested & recovered. On Monday I found my 20 minute sessions at and around FTP extremely hard. Although I forced myself to hold the power, my fatigued, tired, un-recovered possibly damaged muscles were painful, my breathing was harder, deeper & faster and heart rate was increasing and going higher as the sessions progressed, though the power remained the same. I completed the sessions at the power desired but at great cost.

These sessions therefore had a greater metabolic cost and a greater physiological cost and were more stressful than usual, should they get more TSS points?

Normalized power takes into account the greater physiological cost of harder efforts followed by less hard efforts compared to just average power, so would TSS be improved if it did allow for sessions being harder when you start with residual fatigue?

 

[CoachFergie]

With regards to fatigue, what would have worse? Post what was in the text book even if it left me open to criticism or to have only quoted what I felt served my argument???

I hate it when people cherry pick the literature to find stuff that suits their purpose and IGNORE everything published.

The current way TSS and NP work it doesn't take into account cycling fatigue prior to the ride not any other type of fatigue.

However one should be using the Performance Manager and you might expect to see a high acute training load and low training stress balance indicating that trying to do intense efforts is ill advised.

 

[Retro Trev]

With regards to fatigue, what would have worse? Post what was in the text book even if it left me open to criticism or to have only quoted what I felt served my argument???

I hate it when people cherry pick the literature to find stuff that suits their purpose and IGNORE everything published.

The current way TSS and NP work it doesn't take into account cycling fatigue prior to the ride not any other type of fatigue.

However one should be using the Performance Manager and you might expect to see a high acute training load and low training stress balance indicating that trying to do intense efforts is ill advised.

Thanks and understood.

 

[Retro Trev]

A thought,

Sky set great store in their warm down policy. They must have found a benefit in doing this - I assume minimising residual fatigue and speeding recovery.

If this is the case, this warming down must alter the training stress? But how would they allow for this in TSS and Performance manager?

 

[CoachFergie]

Would you also account for mins spent in Cold Water Immersion, mins on the massage table, hours spent sleeping to determine TSS and to fine tune the PMC as well?

 

[Retro Trev]

Would you also account for mins spent in Cold Water Immersion, mins on the massage table, hours spent sleeping to determine TSS and to fine tune the PMC as well?

I would take them all into account when evaluating a days training. I do not use TSS and performance manager tools.

 

[CoachFergie]

But none of those things are "training" or "riding", or "exercise" so how could they contribute to a training stress score?

If you don't use those metrics then why ask the question in the first place?

 

[Retro Trev]

But none of those things are "training" or "riding", or "exercise" so how could they contribute to a training stress score?

If you don't use those metrics then why ask the question in the first place?

A lot of people do use it so I'm interested in what it does and does not do.

I had assumed wrongly because Normalised Power made an attempt to take into consideration the true physiological stress of an effort rather than just count watts that TSS was more complicated.

Do you have any use for heart rate?

 

[FrankDay]

But none of those things are "training" or "riding", or "exercise" so how could they contribute to a training stress score?

If you don't use those metrics then why ask the question in the first place?

TSS is nothing more than a "system" devised to help athletes get a better handle on their training. It is not perfect as you have pointed out as a similar power effort when one is tired is probably a bigger stress on the body than when one is fresh. Or, if one didn't get a good nights sleep (when a lot of repair is going on) then the next days training stress for the same effort is likely to be higher on the body than if one had a good nights sleep. But, TSS, does not take this into account because it is designed to be simple and understandable. If you want to take these modifying factors into account in devising your own program feel free to do so. In fact, devise your own system that takes sleep into account, or repeated stress, or anything else and call it TSS-M (Training Stress Score - Modified) and see if it catches on.

 

[FrankDay]

I was using the trem 'fatigue' in the same way Dr Coggan refers to it. I was not using it in the terms of fatigue only ocurring at the instant one is unable to maintain the stipulated power.

I read this below recently - this is the type of fatigue I was referring to.

http://www.pponline.co.uk/encyc/the-slow-component-of-vo2-understand-it-to-go-faster-39797

My question is this,

I did a 20 minute max test on Sunday when fully rested & recovered. On Monday I found my 20 minute sessions at and around FTP extremely hard. Although I forced myself to hold the power, my fatigued, tired, un-recovered possibly damaged muscles were painful, my breathing was harder, deeper & faster and heart rate was increasing and going higher as the sessions progressed, though the power remained the same. I completed the sessions at the power desired but at great cost.

These sessions therefore had a greater metabolic cost and a greater physiological cost and were more stressful than usual, should they get more TSS points?

Normalized power takes into account the greater physiological cost of harder efforts followed by less hard efforts compared to just average power, so would TSS be improved if it did allow for sessions being harder when you start with residual fatigue?

In the article you referenced Coggan is using the fatigue term correctly, as I did. The proof of that is their explanation of the slow component of VO2 where, as the muscle loses contractile ability due to fatigue (muscle fibers either contract full force or not at all - we moderate total contractile force by the number of fibers invoked) more muscle fibers must be contracted to achieve the same force and the more muscle fibers invoked the more of the less efficient FT fibers are needed. (There are other explanations that might explain this phenomenon also - perhaps acting in parallel - but this is probably the main one I would guess). This one issue is probably the main explanation as to why the longer the event the slower we have to go, even if we are entirely aerobic.

 

[acoggan]

If you don't use those metrics then why ask the question in the first place?

Because he's a troll.

 

[CoachFergie]

Ah so he is. Bad troll!!!

I don't forum as much as I did. See he was banned from TT forum and in the Sock Puppet stage on Bike Radar.

What exciting lives some people lead.

 

[Retro Trev]

Because he's a troll.

Andrew,

In your own words,


"A greater limitation to the entire concept, though, is that the
basic premise – i.e., that you can adequately describe the training load
and the stress it imposes on an individual based on just one number
(TSS), completely ignoring how that “score” is achieved and other
factors (e.g., diet, rest) – is, on its face, ridiculous. In particular,
it must be recognized that just because, e.g., two different training
programs produce the same weekly TSS total, doesn’t mean that an
individual will respond in exactly the same way."

Your system is plain daft. You might as well just add up the watts.

Your system has never been scientifically validated. You have never published a paper on your system.

If there was any evidence your system predicts anything why have you not published a paper?

As usual when I point out the flaws in your system you resort to abuse or call me a troll.

I consistently hold the same views, it is for those views you and others resort to abuse and report me to moderators in an attempt to get me banned.


Your system is flawed. It is nothing more than a watts addition system. It is just plain stupid to think you can describe training load and the stress it imposes on an individual with a number which is derived from wattage alone.