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The pedaling technique thread

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Re: Re:

13 Dec 2016 00:38

JayKosta wrote:
backdoor wrote:,,,
http://www.cobbcycling.com/catalog/crankset/

How do shorter cranks eliminate dead spot in pedalling ?

-----------------------------
I couldn't find any place in the CobbCycling article about short cranks that mentioned 'eliminating the (10-2) deadspot'.
My reading of the article is that his speculation is shorter chanks might be a benefit because their 10-2 'foot movment and foot vertical travel' distances are less than with a longer crank - and the distance decrease through the deadspot would reduce fatigue. But the 10-2 deadspot is still present.

Did you see a spot in the article that mentions eliminating the deadspot?

Jay Kosta
Endwell NY USA



It's not in the article, it's further down where the advantages of shorter cranks are listed. " DEAD SPOT ELIMINATION "
backdoor
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Re: Re:

13 Dec 2016 15:18

backdoor wrote:...
It's not in the article, it's further down where the advantages of shorter cranks are listed. " DEAD SPOT ELIMINATION "

------------
Yes, I see it now -
"Dead spot elimination in the pedal stroke to reduce muscle fatigue and improve your run off the bike"

Based on what was claimed and described in the article, I suspect that sentence is just badly written. or whoever wrote it did not understand what was written in the article.

If it was written as -
'Reduce muscle fatigue during the dead spot and improve your run off the bike'
it would agree with the article.
But, that doesn't sound as good as 'dead spot elimination to reduce muscle fatigue' ...

Jay Kosta
Endwell NY USA
JayKosta
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Re: Re:

15 Dec 2016 21:58

JayKosta wrote:
backdoor wrote:...
It's not in the article, it's further down where the advantages of shorter cranks are listed. " DEAD SPOT ELIMINATION "

------------
Yes, I see it now -
"Dead spot elimination in the pedal stroke to reduce muscle fatigue and improve your run off the bike"

Based on what was claimed and described in the article, I suspect that sentence is just badly written. or whoever wrote it did not understand what was written in the article.

If it was written as -
'Reduce muscle fatigue during the dead spot and improve your run off the bike'
it would agree with the article.
But, that doesn't sound as good as 'dead spot elimination to reduce muscle fatigue' ...

Jay Kosta
Endwell NY USA


Looks like Cobb is not the only one who does not know what dead spot elimination means.
http://www.cyclingweekly.co.uk/news/product-news/are-shorter-cranks-better-188288
In TT's the root cause of interference in pedalling around TDC when using 170 cranks is not the length of the crank, it's because the rider does not know how to use it for best effect in this sector.
backdoor
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Re: Re:

17 Dec 2016 19:12

JayKosta wrote:
backdoor wrote:...
It's not in the article, it's further down where the advantages of shorter cranks are listed. " DEAD SPOT ELIMINATION "

------------
Yes, I see it now -
"Dead spot elimination in the pedal stroke to reduce muscle fatigue and improve your run off the bike"

Based on what was claimed and described in the article, I suspect that sentence is just badly written. or whoever wrote it did not understand what was written in the article.

If it was written as -
'Reduce muscle fatigue during the dead spot and improve your run off the bike'
it would agree with the article.
But, that doesn't sound as good as 'dead spot elimination to reduce muscle fatigue' ...

Jay Kosta
Endwell NY USA


A coach's understanding of how an oval shaped chainring works through the dead spot.

http://www.bikeradar.com/gear/article/technique-three-ways-to-pedal-faster-26895/
backdoor
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20 Dec 2016 21:29

I don't put much faith in articles from cycling magazines. I have been asked to do an article on preparing for the Tour of New Zealand and was told to edit certain parts because the article would conflict with advertisers of various gimmicky products.

Amusing Noel would link to an article from 2010 boasting about Wiggins using Osymetric rings when we know he dumped them and carried on his winning ways.
Hamish Ferguson
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Re:

21 Dec 2016 00:58

CoachFergie wrote:I don't put much faith in articles from cycling magazines. I have been asked to do an article on preparing for the Tour of New Zealand and was told to edit certain parts because the article would conflict with advertisers of various gimmicky products.

Amusing Noel would link to an article from 2010 boasting about Wiggins using Osymetric rings when we know he dumped them and carried on his winning ways.



This was meant to demonstrate the ignorance of the coach on this topic, which you obviously failed to spot.
backdoor
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Re: Re:

21 Dec 2016 02:34

How are we to distinguish the ignorance you trot out as fact from the ignorance you trot out as ignorance?

backdoor wrote:This was meant to demonstrate the ignorance of the coach on this topic
PhitBoy
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20 Feb 2017 23:16

https://www.youtube.com/watch?v=tFNBKRIhCP0

Some interesting stuff towards the end on measuring pedalling through the stroke.
Hamish Ferguson
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Re:

24 Feb 2017 20:13

CoachFergie wrote:https://www.youtube.com/watch?v=tFNBKRIhCP0

Some interesting stuff towards the end on measuring pedalling through the stroke.



Nothing new there but it does answer one question, no research has been done comparing unweighting (creating a resistance free path for the non powering pedal) to the natural technique.
backdoor
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Re: Re:

24 Feb 2017 21:04

backdoor wrote:
CoachFergie wrote:https://www.youtube.com/watch?v=tFNBKRIhCP0

Some interesting stuff towards the end on measuring pedalling through the stroke.



Nothing new there but it does answer one question, no research has been done comparing unweighting (creating a resistance free path for the non powering pedal) to the natural technique.


Noel,

These are the folks I offered to help you get hooked up with so that you could demonstrate your technique. For some reason you didn't seem to want to do so. Why is that?

Hugh
Genetics load the gun, lifestyle pulls the trigger.
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25 Feb 2017 00:40

Yeah no one since Mornieux, or the Ostler studies where they compared riding clipped and flat pedals or instructing riders to pull up on the upstroke.

All this pedalling, crank length, gimmikcrank, oval rings nonsense all hinges on claims to generate more power. Fails to appreciate that increasing power is easy. Sustainability is the key. No changes in the above studies and the only studies showing any benefit, to efficiency not performance, failed to be observed in any subsequent studies.
Hamish Ferguson
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Re:

25 Feb 2017 10:56

CoachFergie wrote:Yeah no one since Mornieux, or the Ostler studies where they compared riding clipped and flat pedals or instructing riders to pull up on the upstroke.

All this pedalling, crank length, gimmikcrank, oval rings nonsense all hinges on claims to generate more power. Fails to appreciate that increasing power is easy. Sustainability is the key. No changes in the above studies and the only studies showing any benefit, to efficiency not performance, failed to be observed in any subsequent studies.


Could the sustainability of the riders you have trained to peak performance be further improved ?
backdoor
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Re:

13 Mar 2017 23:56

CoachFergie wrote:Yeah no one since Mornieux, or the Ostler studies where they compared riding clipped and flat pedals or instructing riders to pull up on the upstroke.

All this pedalling, crank length, gimmikcrank, oval rings nonsense all hinges on claims to generate more power. Fails to appreciate that increasing power is easy. Sustainability is the key. No changes in the above studies and the only studies showing any benefit, to efficiency not performance, failed to be observed in any subsequent studies.


http://trstriathlon.com/elliptical-chain-rings-dont-work-because-you-wont-let-them/

What will Leong find ? Nothing because performance improvement from pedalling can only come from a complete change in muscle coordination and this is controlled by the brain and the objectives it is given, not by changing shape of equipment.
backdoor
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14 Mar 2017 04:11

Ha ha, very funny, and wrong. Fernandez Pena showed the muscle coordination changed when using Gimmickcranks and as soon as subjects went back to normal cranks the muscle coordination changes back. Don't they teach this at Crackpot U?
Hamish Ferguson
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Re:

14 Mar 2017 21:44

CoachFergie wrote:Ha ha, very funny, and wrong. Fernandez Pena showed the muscle coordination changed when using Gimmickcranks and as soon as subjects went back to normal cranks the muscle coordination changes back. Don't they teach this at Crackpot U?


I mean changing coordination in the power stroke not in the ineffective recovery stroke. Gcrank technique did not change coordination because it was only a painful and more extreme version of the weaker circular technique, so it should have come as no surprise when riders using it reverted back to the more effective mashing technique. To improve performance with non round rings a rider would have to increase the pedal/crank speed around 3 o'c to that of a round chainring at the same cadence. In TT's that would mean having to increase power application in a sector where close to maximal torque was already being applied to the cranks.
backdoor
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14 Mar 2017 22:18

Hmmmm, Fernandez Penas data shows that they did change coordination.

Real data v delusion. Choose wisely people.
Hamish Ferguson
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Re:

14 Mar 2017 22:57

CoachFergie wrote:Hmmmm, Fernandez Penas data shows that they did change coordination.

Real data v delusion. Choose wisely people.


Did they change muscle coordination from that of the commonly used circular style ?
backdoor
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15 Mar 2017 19:09

Very few use the "commonly used" circular style.
Hamish Ferguson
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Re:

16 Mar 2017 11:55

CoachFergie wrote:Very few use the "commonly used" circular style.


And there you have the explanation for that increased negative work mentioned below. Also unlike the 'Rotor Crank' non round rings have the disadvantage of a double action occurring in each pedalling circle. But even if this negative work is completely eliminated, you still have the problem of having to increase power in a sector where maximal power is already being applied. The sensible way to go is to effectively increase power where the leg is idling.

" Abstract
Previous studies have sought to improve cycling performance by altering various aspects of the pedaling motion using novel
crank–pedal mechanisms and non-circular chainrings. However, most designs have been based on empirical data and very few have
provided significant improvements in cycling performance. The purpose of this study was to use a theoretical framework that included a
detailed musculoskeletal model driven by individual muscle actuators, forward dynamic simulations and design optimization to
determine if cycling performance (i.e., maximal power output) could be improved by optimizing the chainring shape to maximize average
crank power during isokinetic pedaling conditions. The optimization identified a consistent non-circular chainring shape at pedaling
rates of 60, 90 and 120 rpm with an average eccentricity of 1.29 that increased crank power by an average of 2.9% compared to a
conventional circular chainring. The increase in average crank power was the result of the optimal chainrings slowing down the crank
velocity during the downstroke (power phase) to allow muscles to generate power longer and produce more external work. The data also
showed that chainrings with higher eccentricity increased negative muscle work following the power phase due to muscle
activation–deactivation dynamics. Thus, the chainring shape that maximized average crank power balanced these competing demands
by providing enough eccentricity to increase the external work generated by muscles during the power phase while minimizing negative
work during the subsequent recovery phase.
r 2008 Elsevier Ltd. All rights reserved.
Keywords: Forward dynamic simulation; Design optimization; Eccentric chainring; Cycling efficiency . "
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Re: Re:

16 Mar 2017 13:56

backdoor wrote:...
The sensible way to go is to effectively increase power where the leg is idling.
...

----------------
Yes, short term power could be increased that way, but at what cost to endurance due to increased muscle fatigue? It wouldn't be wise to activate low efficiency muscles that drain O2 and fuel except for short duration critical needs.

Jay Kosta
Endwell NY USA
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