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The Powermeter Thread

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20 Jan 2015 18:16

Alex Simmons/RST wrote:Coapman asked about data from a "torque meter around the circle". Providing the data on the net torque from both cranks is more than sufficient for this purpose.

Here is what he wrote
If it is a torque meter (around the circle) in addition to a power meter, the answer is yes as this will confirm what should have already been obvious to scientists that this man (when at max power output in the finishing straight on this track) is starting his power stroke around 11 and applying maximal torque at 12).
Torque analyses that involve net torque (SpinScan, SRM) must make a certain assumption to do their analysis. The assumption they are forced to make is that NOTHING is done on the backstroke between 6 and 12. Having made this assumption they can then say what they see is what the rider is doing on the downstroke (and of course, "everyone" knows that is where all the power is generated so that is all that counts). The problem is, of course, that having made the assumption that NOTHING is done on the upstroke (between 6 and 12) that it is not possible to show that the rider is starting the power stroke at 11 since they assume he is not. Hence, I think it is quite clear that "Providing the data on the net torque from both cranks is" NOT "more than sufficient for this purpose." In fact, it is demonstrably useless for this purpose.
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FrankDay
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20 Jan 2015 21:37

FrankDay wrote:Here is what he wroteTorque analyses that involve net torque (SpinScan, SRM) must make a certain assumption to do their analysis. The assumption they are forced to make is that NOTHING is done on the backstroke between 6 and 12. Having made this assumption they can then say what they see is what the rider is doing on the downstroke (and of course, "everyone" knows that is where all the power is generated so that is all that counts). The problem is, of course, that having made the assumption that NOTHING is done on the upstroke (between 6 and 12) that it is not possible to show that the rider is starting the power stroke at 11 since they assume he is not. Hence, I think it is quite clear that "Providing the data on the net torque from both cranks is" NOT "more than sufficient for this purpose." In fact, it is demonstrably useless for this purpose.


SRM makes no assumptions. They simply report net torque from both cranks. They make no claim about the independent torque applied to each crank, nor attempt to suggest their data can.

This net torque data is more than sufficient to answer Noel's questions. For sure having independent crank torque data can help further understand such things, but it isn't necessary for addressing what Noel has been banging on about for decades.
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20 Jan 2015 21:51

By the way, pedal force data from a bicycle ridden on a track, and on the road up and down hills was first reported in the scientific literature in 1896. Yes, that's EIGHTeen ninety six.

Sharp, A. (1896). Bicycles and tricycles: an elementary treatise on their design and construction. Start from bottom of page 268.

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It's funny to read their commentary on pedalling technique in section 215. At least we know the pedal technique myths tossed about on here are not original, and have been about for over 120 years.
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20 Jan 2015 22:32

Alex Simmons/RST wrote:SRM makes no assumptions. They simply report net torque from both cranks. They make no claim about the independent torque applied to each crank, nor attempt to suggest their data can.

This net torque data is more than sufficient to answer Noel's questions. For sure having independent crank torque data can help further understand such things, but it isn't necessary for addressing what Noel has been banging on about for decades.
It is impossible for the net torque data for two cranks together to mean anything about the individual crank torque (Noel's question) without making some assumptions. It is what SpinScan does. It is what SRM does otherwise it couldn't give you a left/right balance (and there is no guarantee even that is correct because of the assumptions made). The only thing that can be learned from such an analysis is how "smooth" the stroke is overall. Nothing is learned about the contribution of the two different cranks around their each individual circle that leads to that overall result.
Life is short, both reading my posts and training with PowerCranks will make it seem longer
FrankDay
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20 Jan 2015 22:58

Alex Simmons/RST wrote:By the way, pedal force data from a bicycle ridden on a track, and on the road up and down hills was first reported in the scientific literature in 1896. Yes, that's EIGHTeen ninety six.
...
It's funny to read their commentary on pedalling technique in section 215. At least we know the pedal technique myths tossed about on here are not original, and have been about for over 120 years.
I look forward to seeing your data, scientific evidence, to suggest that what they say in section 215 is, indeed, a myth. In fact, it is amazing that a better pedaling technique has been advocated since 1896 and the average cyclist still cannot do it just as described in 1896. Instead, because they cannot do it people use this continued use of a theoretically lesser technique as proof that what they do (the theoretically lesser technique) must be superior instead of considering this is simply evidence it is very difficult to learn and change. Believe whatever you must to keep on doing what you are doing.
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FrankDay
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20 Jan 2015 23:20

Keep it in the right forum Frank. This is about power meters, not pedalling technique.
JamesCun
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21 Jan 2015 00:19

JamesCun wrote:Keep it in the right forum Frank. This is about power meters, not pedalling technique.
My friend, I was simply responding to the OT post by Alex Simmons. Of course, the problem is there is a certain amount of overlap when power meters also, purportedly, measure pedaling technique. Where to draw the line? What a conundrum.
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FrankDay
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21 Jan 2015 00:37

An interesting representation of Jack Haig, Neil van der Ploeg and Steele von Hoff's power profiles from yesterday's TDU stage.

http://www.todaysplan.com.au/wp-content/themes/todaysplan/embed/replay
How to ride like a Tour champion!

proof noun (SHOWING TRUTH)

B2 [C or U] a fact or piece of information that shows that something exists or is true

http://dictionary.cambridge.org/dict...ritish/proof_1


evidence noun [U] uk /ˈev.ɪ.dəns/ us

B2 one or more reasons for believing that something is or is not true

http://dictionary.cambridge.org/dict...itish/evidence
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21 Jan 2015 00:42

Wow, that is very cool.

I see Todays Plan allows people to create their own training programmes or even cooler have the site developed programmes based on courses.

Will be investing the site.
Hamish Ferguson
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26 Feb 2015 22:43

TBH Didn't like the lack of functionality with Todays Plan so have stopped that experiment.

That being said, still think TrainingPeaks is waaaay behind what it could be for professional coach and athlete.

My study on long term training metrics earned me my Masters Degree so the next step is to try and get the study published, then start working on a PhD.
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26 Feb 2015 23:19

CoachFergie wrote:TBH Didn't like the lack of functionality with Todays Plan so have stopped that experiment.

That being said, still think TrainingPeaks is waaaay behind what it could be for professional coach and athlete.

My study on long term training metrics earned me my Masters Degree so the next step is to try and get the study published, then start working on a PhD.
Nobody has yet to show that any of this information makes any difference anyhow so how is it possible to say someone is "way behind" someone else who also hasn't demonstrated a difference in outcome?
Life is short, both reading my posts and training with PowerCranks will make it seem longer
FrankDay
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26 Feb 2015 23:39

FrankDay wrote:Nobody has yet to show that any of this information makes any difference anyhow so how is it possible to say someone is "way behind" someone else who also hasn't demonstrated a difference in outcome?


Good, then plenty of scope for me to make a dent in the knowledge with my PhD!
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27 Feb 2015 00:27

CoachFergie wrote:Good, then plenty of scope for me to make a dent in the knowledge with my PhD!
Have fun and good luck! Until then I think you should refrain from declaring one side or the other (or both sides) the winner as there may be no benefit to using this data at all, regardless of how it is presented (at least none has yet been demonstrated).
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27 Feb 2015 00:50

FrankDay wrote:Have fun and good luck! Until then I think you should refrain from declaring one side or the other (or both sides) the winner as there may be no benefit to using this data at all, regardless of how it is presented (at least none has yet been demonstrated).


Already well established that the power meter measures what we think it measures. That some of those measures have an acceptable level of error and some don't.

Well established that a change in power is has better relationship with an improvement in actual performance than any other measure related to performance.

Opportunities for further study include, determination of threshold, determination of training stress scores, determination of anaerobic work capacity and the use of all those metrics to guide the coaching process.

The benefit comes from training, recovering, eating well, having a good process, being well set up on the bike, have good riding skills, using your gearing well etc. A power meter is one way of measuring this.
Hamish Ferguson
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27 Feb 2015 00:54

CoachFergie wrote:Already well established that the power meter measures what we think it measures. That some of those measures have an acceptable level of error and some don't.

Well established that a change in power is has better relationship with an improvement in actual performance than any other measure related to performance.

Opportunities for further study include, determination of threshold, determination of training stress scores, determination of anaerobic work capacity and the use of all those metrics to guide the coaching process.

The benefit comes from training, recovering, eating well, having a good process, being well set up on the bike, have good riding skills, using your gearing well etc. A power meter is one way of measuring this.
Wow!!! You don't see an opportunity for further study that using a power meter (in any particular way) actually has benefits in improving training outcome for the athlete over what can be done without one? What good does all that other stuff do if it doesn't result in an improved outcome?
Life is short, both reading my posts and training with PowerCranks will make it seem longer
FrankDay
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27 Feb 2015 01:12

FrankDay wrote:Wow!!! You don't see an opportunity for further study that using a power meter (in any particular way) actually has benefits in improving training outcome for the athlete over what can be done without one? What good does all that other stuff do if it doesn't result in an improved outcome?


Back to trolling Frank. How typical.

Do people lose weight because they weigh themselves?
Hamish Ferguson
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27 Feb 2015 01:12

FrankDay wrote:Wow!!! You don't see an opportunity for further study that using a power meter (in any particular way) actually has benefits in improving training outcome for the athlete over what can be done without one? What good does all that other stuff do if it doesn't result in an improved outcome?


I don't know why anyone bothers responding here.

A power meter is a great way to measure that outcome and to be able to measure that outcome without doing a race. A power meter is a measurement device. It is very, very good at measuring what it claims to measure.
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27 Feb 2015 01:20

JamesCun wrote:I don't know why anyone bothers responding here.

A power meter is a great way to measure that outcome and to be able to measure that outcome without doing a race. A power meter is a measurement device. It is very, very good at measuring what it claims to measure.


Trolls gotta troll. Frank has nothing but his pathetic Straw Man.

I see the Imagination Game is still carrying on in the Pedalling Technique thread.

People should report his trolling so this forum can make progress.
Hamish Ferguson
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27 Feb 2015 01:23

CoachFergie wrote:Trolls gotta troll. Frank has nothing but his pathetic Straw Man.

I see the Imagination Game is still carrying on in the Pedalling Technique thread.

People should report his trolling so this forum can make progress.


I don't think the pedalling technique thread has any hope. Probably better to focus on preserving this thread for useful discussion.
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27 Feb 2015 01:39

FrankDay wrote:Nobody has yet to show that any of this information makes any difference anyhow so how is it possible to say someone is "way behind" someone else who also hasn't demonstrated a difference in outcome?


It's been particularly useful in demonstrating what doesn't work.
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