Pedal based Power Monitoring Systems

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bricky21
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by bricky21

Rick wrote:Unbiased readers can easily review the evolution of this thread and decide who is ignorant and insulting.


+1000Though I think you and I'd disagree on who's been ignorant and insulting :wink:

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Tapeworm
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by Tapeworm

Rick wrote:Sorry, but I think I am finished discussing this.
I have produced numerous references that directly discredit and contradict your assertions, and despote my numerous requests you produce only one study that does not support your assertions except through your own convoluted logic.


Numerous references? Two quote from assumptions of authors in a book? Outstanding. When you have some credible assertion maybe you'll actually have a reason for believing your bias. As yet you've got nothing, no logical physiological basis to explain why pedal asymmetry, when "corrected", will yield more power, no study to suggest that this can be effectively done.

You cannot explain the simple questions I have posed which perhaps lead me to think you don't actual know why you have this bias. Happy to argue the semantics of physiology but you're not even doing that. I say why, you say "no" without reason or logic. I am more than wiling to flip-flop on matters and having been a subject of the single leg study and examining this as a training method. But not for the reasons you have seem to seized on. Do some research. Come up with actual REASONS why you assert why correcting pedal asymmetry is a boost for power and then your arguements will have real weight.
"Physiology is all just propaganda and lies... all waiting to be disproven by the next study."
"I'm not a real doctor; But I am a real worm; I am an actual worm." - TMBG

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Rick
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by Rick

Numerous references? Two quote from assumptions of authors in a book? Outstanding. When you have some credible assertion maybe you'll actually have a reason for believing your bias. As yet you've got nothing, no logical physiological basis to explain why pedal asymmetry, when "corrected", will yield more power, no study to suggest that this can be effectively done.


OK....I will try this one more time.
PLEASE....try to read AND UNDERSTAND exactly what I am saying.
*I* don't have an assertion.
*I* am NOT claiming that asymmetry will do anything when corrected.
*I* am not the one claiming to know anything about this.

*My* only comment (and please reread the thread to confirm) is that measuring pedal asymmetry *may* prove beneficial in some way to some people. "Mmay" means "possibly". I am open minded about it and would welcome more research.
YOU assert that it is irrelevant, worthless, wdefinitely can't help...etc...whatever. YOU assert there is already abundant evidence.
SO WHERE IS IT ?!?!?
I ask WHY you are so confident in your assertions (rchung was also a big asserter of this)

I produce two studies that directly contradict you ONLY BECAUSE IT WAS EASY TO FIND THEM WITHIN ABOUT 5 MINUTES OF GOOGLING!
I don't have to prove anything. I am not asserting anything!
Yet you make your assertions and do not produce ANY study that supports it. You *infer* that it supports you through your own logic, but frankly I just think your logic is weak.

*YOU* are the one purporting to KNOW and to be stating that asymmetry correction is worthless.

CAN'T YOU PRODUCE AT LEAST ONE STUDY THAT REALLY SUPPORTS YOR CLAIM ?!?!?!

You cannot explain the simple questions I have posed which perhaps lead me to think you don't actual know why you have this bias.

Huh ?!?!? My only "bias" is to be open-minded on the subject. Numerous times now I have asked you for a study that supports your claims, and all I get is more of this pompous bluster. How about simply providing the evidence. IS THAT REALLY SO HARD ?!?!?

.....Come up with actual REASONS why you assert why correcting pedal asymmetry is a boost for power and then your arguements will have real weight.


Let me try ONCE AGAIN: I have not assert that it does. {My God....would you please reread the thread at this point!}
But I have at least provided two references to noted researchers who say it does.
That is why I would like to see the avidence you claim counters it.

I have this feeling that you have been so incensed by anyone who woul dare to question your opinions that you have turned this into a battle of your belief vs. mine....BUT I DON"T HAVE BELIEF... IF YOU PRODUCED THE EVIDENCE, I WOULD BELIEVE YOU!!!!!

Now then: Using THE STUDY YOU CITED: I will give a theory as to why knowing both sides power is valuable. Note that I am not claiming this is true. I am not an expert. I just say his seems plausible.
Although the kicking dominant leg contributed significantly greater average crank power than the non-dominant leg for the subject sample, the non-dominant leg contributed significantly greater average positive power and average negative power than the dominant leg.
So, if a leg is producing negative power, the body is already producing that power. It doesn't require any increase in the aerobic power of the body to stop producing negative power. But it might require KNOWING about that negative power.
Let's say a single-sided power meter is reading 100 Watts. But the left leg is producing 5 watts negative. So the body was really producing 105 Watts. Now correct the asymmetry, and the 105 watts all becomes useful watts.
JUST A THEORY !!!!....If there is EVIDENCE to the contrary, I will believe it.

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devinci
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by devinci

This is getting fking boring and the topic is sliding away imo

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CoachFergie
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by CoachFergie

amaferanga wrote:I guess the question is what do you actually do with the information if it does turn out you have a 60/40, 70/30 or whatever split? And surely if you are at the extreme with regards imbalance then you wouldn't need a power meter to tell you that?


Ding ding ding! We have a winner!!!

Having performed a bike fit or thousand and coached a similar number of riders in the last 20 years any imbalance that great stands out like dogs balls. Limb length differences, injury, amputation etc. Those are the things that need to be corrected (or corrected for) not the imbalance.
Hamish Ferguson
Cycling Coach

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Tapeworm
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by Tapeworm

Rick wrote:I ask WHY you are so confident in your assertions (rchung was also a big asserter of this)

I produce two studies that directly contradict you ONLY BECAUSE IT WAS EASY TO FIND THEM WITHIN ABOUT 5 MINUTES OF GOOGLING!


Except, they don't.



Yet you make your assertions and do not produce ANY study that supports it. You *infer* that it supports you through your own logic, but frankly I just think your logic is weak.


No, the logic is sound. See below.


Huh ?!?!? My only "bias" is to be open-minded on the subject. Numerous times now I have asked you for a study that supports your claims, and all I get is more of this pompous bluster.


Hmmm. Pompous bluster indeed.

Here is EXACTLY how balancing power out put can increase power output:
1 leg - 50%
If I now start using the other leg: 100%
That is a 100% increase !


You don't have a belief? Really. Yet you are convinced that the "flimsy data" is incorrect. But you don't know why.

Now then: Using THE STUDY YOU CITED: I will give a theory as to why knowing both sides power is valuable. Note that I am not claiming this is true. I am not an expert. I just say his seems plausible.
Although the kicking dominant leg contributed significantly greater average crank power than the non-dominant leg for the subject sample, the non-dominant leg contributed significantly greater average positive power and average negative power than the dominant leg.
So, if a leg is producing negative power, the body is already producing that power. It doesn't require any increase in the aerobic power of the body to stop producing negative power. But it might require KNOWING about that negative power.
Let's say a single-sided power meter is reading 100 Watts. But the left leg is producing 5 watts negative. So the body was really producing 105 Watts. Now correct the asymmetry, and the 105 watts all becomes useful watts.
JUST A THEORY !!!!....If there is EVIDENCE to the contrary, I will believe it.


Well rchung cited that study. I cited the single leg counterweight.

Now to answer the questions I posted in light of that study. The recorded power of an individual leg was great than half the power output of both legs. That means, unless there is a huge imbalance the "weaker" leg is already capable of producing power that would allow it to bring it to a 50/50 balance. But it doesn't. See earlier comments about exceeding the limits of the system. This is all rather simple.
"Physiology is all just propaganda and lies... all waiting to be disproven by the next study."
"I'm not a real doctor; But I am a real worm; I am an actual worm." - TMBG

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CoachFergie
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by CoachFergie

Simple little n=1 to support Tapeworm's point. I have always felt I favoured and had a stronger R leg than my left. Did a couple of 20sec efforts today and found the opposite. Higher peak power for the L leg than the R leg. Slightly better ave power for the R leg though. Did this at the end of a Max Aerobic Power workout. I was able to produce more power for a single leg effort than I could sustain in the MAP efforts. So strength isn't an issue even when pedalling in a different manner than I am trained to and I clearly have the available force. Any imbalance perceived or measured (have spent some time using a Wattbike, hate them) is more likely to reflect greater degeneration in my left hip than the right and a growing greater lack of mobility as well. Rather than any conscious decision to push harder on one side that could easily be corrected.
Hamish Ferguson
Cycling Coach

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Rick
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by Rick

That means, unless there is a huge imbalance the "weaker" leg is already capable of producing power that would allow it to bring it to a 50/50 balance. But it doesn't. See earlier comments about exceeding the limits of the system. This is all rather simple.


OK....so....uhhh....there is no better study I guess.

...and you ignore my point that using my thought-experiment and the the study that rchung provided, the body is already producing the 105 watts. No increase in aerobic capacity would be needed. All one would need to do eliminate (correct) the 5 inefficient watts (due to the 5 watts of negative power being produced by the 'inefficient' leg) into 5 watts of usefil power.
5 watts is not "large". But figure how much time that would save in a 20 minute effort. Maybe it is only 1 watt. I don't know. But you can fix it if you don't know about it.
In fact, this would work even if there is no "asymmetry". Even if both legs are equally producing negative power, (negative power being a small component of force that 'fight' crank rotation in some part of he pedal stoke) then eliminating the negative power gives a boost (however small) to the effective power.
BUT YOU CAN'T EVEN KNOW ABOUT THE NEGATIVE POWER UNLESS YOU CAN DETECT AND MEASURE IT WITH A BILATERAL FORCE MONITOR SYSTEM.


So to summarize:
1. You have no data that supports your contentions (or at least you refuse to reveal it for whatever odd reasons you may have) .
2. At least two very well known cycling 'experts' directly contradict your assertions. They were very easy to google-up. It was not some big research project.
3. You ignore reasoning that shows a bilateral power monitor would be valuable even from the data that rchung provided and you think is valid.

So this all really has gone on to the point of absolutely ludicrous. I am really just dumbfounded and laughing that you seem to have taken this so personally. I have no ill will whatsoever. I have no idea why you would keep twisting my arguments abnd refuse to provide some studies that support your claims. If it makes you feel better, I will just say (once again) you are right and I am wrong.

Have a Merry Christmas and Happy New Year; Happy Hannukah, Awesome Kwanzaa, and Joyous Festivus! :thumbup: :thumbup: :thumbup: :beerchug: :beerchug: :beerchug:


By the way. on these statements:
Rick said:

Here is EXACTLY how balancing power out put can increase power output:
1 leg - 50%
If I now start using the other leg: 100%
That is a 100% increase !

To which Tapeworm replied:
You don't have a belief? Really. Yet you are convinced that the "flimsy data" is incorrect. But you don't know why.

This convinces me you have not bothered to reread (and understand)the thread. In context, my statement was a facetious response to rchung's challenge to explain EXACTLY how an bilateral power monitor could be useful. So I quickly made up a straw-man example of how it COULD be useful. I don't BELIEVE it is true. I even stated myself that it was unrealistic and overly simplistic. What I wanted was some real data to show that it is false, partially true, or whatever. But instead of providing any data that would counter it, rchung started with the personal insults.
It occurs to me that maybe your native language isn't English so you are misinterpreting a lot of what I am trying to say ?

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CoachFergie
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by CoachFergie

Appeals to authority, ad hominem attacks and confirmation bias.

Well played Rick.
Hamish Ferguson
Cycling Coach

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Tapeworm
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by Tapeworm

Rick wrote:...and you ignore my point that using my thought-experiment and the the study that rchung provided, the body is already producing the 105 watts. No increase in aerobic capacity would be needed. All one would need to do eliminate (correct) the 5 inefficient watts (due to the 5 watts of negative power being produced by the 'inefficient' leg) into 5 watts of usefil power.
5 watts is not "large". But figure how much time that would save in a 20 minute effort. Maybe it is only 1 watt. I don't know. But you can fix it if you don't know about it.
In fact, this would work even if there is no "asymmetry". Even if both legs are equally producing negative power, (negative power being a small component of force that 'fight' crank rotation in some part of he pedal stoke) then eliminating the negative power gives a boost (however small) to the effective power.
BUT YOU CAN'T EVEN KNOW ABOUT THE NEGATIVE POWER UNLESS YOU CAN DETECT AND MEASURE IT WITH A BILATERAL FORCE MONITOR SYSTEM.


It has been done. So now you're talking about removing negative torque throughout the pedal cycle. Look up Dr Frank Day and powercranks. You'll have a ball. And I thought that "...*I* don't have an assertion. *I* am NOT claiming that asymmetry will do anything when corrected. *I* am not the one claiming to know anything about this...."


So to summarize:
1. You have no data that supports your contentions (or at least you refuse to reveal it for whatever odd reasons you may have) .


The data is there. You just can't seem to understand it.

2. At least two very well known cycling 'experts' directly contradict your assertions. They were very easy to google-up. It was not some big research project.


Never heard of them. And the fact it wasn't a research project is very apparent. On all fronts.

3. You ignore reasoning that shows a bilateral power monitor would be valuable even from the data that rchung provided and you think is valid.


Once again, you don't seem to understand the data provided.

So this all really has gone on to the point of absolutely ludicrous. I am really just dumbfounded and laughing that you seem to have taken this so personally.


Your laughing at me has made me cry. Waaaaaah.

I have no ill will whatsoever. I have no idea why you would keep twisting my arguments abnd refuse to provide some studies that support your claims. If it makes you feel better, I will just say (once again) you are right and I am wrong.


Oh yay, I "won". Seems I'm not the only one with a reading comprehension issue. And I thought you weren't arguing because you "..don't have an assertion...". And despite the explanations and data provided you seem to not understand and now on a tangent of power applied through the cycle as opposed to asymmetry.

This convinces me you have not bothered to reread (and understand)the thread. In context, my statement was a facetious response to rchung's challenge to explain EXACTLY how an bilateral power monitor could be useful. So I quickly made up a straw-man example of how it COULD be useful. I don't BELIEVE it is true. I even stated myself that it was unrealistic and overly simplistic. What I wanted was some real data to show that it is false, partially true, or whatever. But instead of providing any data that would counter it, rchung started with the personal insults.
It occurs to me that maybe your native language isn't English so you are misinterpreting a lot of what I am trying to say ?


Sorry, who's taking it personally? Oh and "...*I* don't have an assertion. *I* am NOT claiming that asymmetry will do anything when corrected. *I* am not the one claiming to know anything about this..."


But since you asked here's some more reading for you:-

http://www.ncbi.nlm.nih.gov/pubmed/20729097" onclick="window.open(this.href);return false;
http://www.ncbi.nlm.nih.gov/pubmed/16569481" onclick="window.open(this.href);return false;
http://www.ncbi.nlm.nih.gov/pubmed/21506038" onclick="window.open(this.href);return false; (this is more about maximal force)
http://www.ncbi.nlm.nih.gov/pubmed/9744943" onclick="window.open(this.href);return false;
"Physiology is all just propaganda and lies... all waiting to be disproven by the next study."
"I'm not a real doctor; But I am a real worm; I am an actual worm." - TMBG

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Rick
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by Rick

OK....this really has gone over into the bizarro world.

I actually looked at your provided links. None of them have anything to do with what we are talking about.
Here is one of the abstracts:
The study investigates the effect of body asymmetry on anticipatory postural adjustments (APAs). Subjects performed a task involving a standard load release induced by a shoulder abduction movement while standing symmetrically or in an asymmetrical stance with either their right or left leg in 45 degrees of external rotation. EMG activities of trunk and leg muscles were recorded during the postural perturbation and were quantified within the time intervals typical of APAs. Anticipatory postural adjustments were observed in all experimental conditions. It was found that asymmetrical body positioning was associated with significant asymmetrical patterns of APAs seen in the right and left distal muscles. These APA asymmetries were dependant upon the side in which the body asymmetry was induced: reduced APAs were observed in the leg muscles on the side of leg rotation, while increased APAs were seen in the muscles on the contralateral side. These findings stress the important role that body asymmetries play in the control of upright posture.

Let me point another example of how you seem to have persistently been misunderstanding my posts. Maybe it is my fault.
I said 'I am laughing" and you responded:
"Your laughing at me has made me cry. Waaaaaah. "
But I didn't say I was laughing at you. I was laughing at the humor of this situtation. It was intended to lighten the conversation, and you have interpreted it as another reason to engage in a personal battle.

But it is over. You have won. I am wrong. You are right.
I am sorry I have wasted your time. :)
(But if you do ever come across any data that is actually relevant to asymmetries in power production I would still like to see them. Just post the links, and I will go read them without comment.)

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Rick
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by Rick

CoachFergie wrote:
Appeals to authority, ad hominem attacks and confirmation bias.

Well played Rick.

When you were adding information to the thread, I was actually reading it and considered you credible.
Last edited by Rick on Tue Dec 27, 2011 3:16 am, edited 1 time in total.

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CoachFergie
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by CoachFergie

Rick wrote:When you were adding information to the thread, I was actually reading it and considered you credible.


When I read your comments I thought the opposite.
Hamish Ferguson
Cycling Coach

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Rick
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by Rick

When I read your comments I thought the opposite.

Well, actually, now that you have jumped into the middle of this with personal insults, even after I tried to avoid fighting with you, I consider you a *f##k* asshole.
So have a nice day. :)

by Weenie


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CoachFergie
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by CoachFergie

Appeals to authority, ad hominem attacks and confirmation bias.

Well played Rick.
Hamish Ferguson
Cycling Coach

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