The Powercrank Thread

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Sep 23, 2010
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coapman said:
If you do not have time to think or concentrate on each power application, your muscles will be only going through the motions around each of the pedalling circles. In slow motion the technique may appear ideal but at a cadence of 90 things are very different. The optimum technique is the one that uses the most powerful muscles for the longest possible time and makes maximal use of the ankle, lower leg and arm muscles, resulting in additional maximal torque at 12 and 1 o'c.
Ugh, the coordination is unconscious for most. Only the intensity is controlled actively. That is how we are able to run at different speeds without thinking about what our leg muscles should be doing. Cycling is the same. No one really thinks about pedaling (except, perhaps, you) when they cycle.
 
Mar 18, 2009
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FrankDay said:
Adding the ankle doesn't change the direction of any force coming from the knee or hip. For most people all the ankle muscles do is try to fix the joint so the larger muscles of the leg can do their work efficiently. Anyhow, if you want to also add the ankle to the equation then go for it. You can flex and extend the ankle at any of these positions also to see if the calf or TA muscles are helping or hurting if used at any point. I look forward to hearing your analysis.

No analysis - not my game and you know it. Just highlighting that you are ignoring another important joint and a large muscle group (gastrocnemius). In my profession, if people focus too closely on a specific area with disregard for the bigger picture then they often make errors.
 
Sep 23, 2010
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elapid said:
No analysis - not my game and you know it.
in this context another term that could be used in place of analysis could be thinking. You may as we'll have said "No thinking - not my game and you know it. " Yet, despite choosing to not think about this stuff you have no qualms about coming here and criticizing those who have tried to think about (analyze) this stuff.
Just highlighting that you are ignoring another important joint and a large muscle group (gastrocnemius). In my profession, if people focus too closely on a specific area with disregard for the bigger picture then they often make errors.
How is it you have determined that the ankle (gastrocnemius muscle) is an important joint when it comes to power production without having done an analysis? I have done that analysis and I have determined that the ankle joint can be effectively ignored for the purposes of this discussion. Perhaps if you could lower yourself to do an analysis regarding this you could let us know what your analysis shows so we could discuss this. Otherwise I think we can only conclude your posts are nothing more than trolling.
 
May 13, 2011
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FrankDay said:
Put your bike on a trainer and put the pedal at a position you would like to examine around the circle. Then unclip and contract the individual muscles to move these two joints in the two different directions (four movements in total) and compare the direction the foot moves to the direction the pedal is moving and ask yourself this question: would this be helpful or hurtful to my desire to generate power or to use my muscles efficiently?

Frank,

You seem to be laboring under the misunderstanding that one can only use a single muscle during any particular part of the pedal stroke. I'd contend that the quads and glutes can be utilized together very effectively. The diagram below is a decent representation of my conception of solid pedal stroke. I run my cleats near mid-foot and therefore make less use of my gastrocnemii than implied in the diagram.

012107pedalstroke.jpg



Hugh
 
Sep 23, 2010
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sciguy said:
Frank,

You seem to be laboring under the misunderstanding that one can only use a single muscle during any particular part of the pedal stroke. I'd contend that the quads and glutes can be utilized together very effectively. The diagram below is a decent representation of my conception of solid pedal stroke. I run my cleats near mid-foot and therefore make less use of my gastrocnemii then implied in the diagram.

012107pedalstroke.jpg



Hugh
Of course cyclist use more than one muscle at a time. Regardless, each muscle only does one thing without regard to what other muscles are doing. Please take your drawing and explain to me how the quads produce any power where the pedal is shown. Contracting the quads extends the knee, moving the foot forward at a time the pedal is moving down and back.

All that illustration shows is what cyclists currently do with the assumption being that if they are doing it it must be producing power. It is this blind acceptance that what most currently do as optimal or necessary that keeps cycling from advancing. Put on your thinking cap!!! There is zero chance that contracting the quads at this point in the circle helps the cyclist. If you think you can make that argument I look forward to hearing it.
 
May 13, 2011
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Frank,

Please try pedaling around the block without extending your lower leg then get back to me. I really can't believe you're this dense.

Hugh
 
Sep 23, 2010
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sciguy said:
Frank,

Please try pedaling around the block without extending your lower leg then get back to me. I really can't believe you're this dense.

Hugh
ugh, of course the knee extends from 3 to 6. It will extend regardless of whether the quads contract there or not as long as the foot stays in touch with the pedal. It is a simple fact however that contracting the quads there works against maximizing power. This is a SIMPLE analysis. Talk about dense.
 
Sep 23, 2010
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One more observation regarding your muscle use illustration Hugh
012107pedalstroke.jpg

Notice the hip flexors are ignored, not even on the chart. I guess that must mean they aren't used at all according to this expert. If it is not possible, according to you, for the knee to extend from 3-6, without active contraction, here how is it possible for the hip to flex from 6-12 on the recovery without a muscle pulling it up? According to your "analysis" it is ok to push the thigh up passively but not let the knee extend passively. Don't you think it about time you started to seriously think about some of the stuff you have accepted as true just because some "expert" said it was so?
 
Sep 23, 2010
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One more observation regarding your muscle use illustration Hugh
012107pedalstroke.jpg

Notice the hip flexors are shown being used between about 9-11 but for most the knee keeps going up until the foot is about at 1:30. How is that possible without passive movement? So, it is not possible, according to you, for the knee to extend from 3-6, without active contraction, but your own chart shows the knee continuing to rise without any active contraction. Why is one possible and the other not? According to your "analysis" it is ok to push the thigh up passively but not let the knee extend passively. Don't you think it about time you started to seriously think about some of the stuff you have accepted as true just because some "expert" said it was so because your position here is both contradictory and makes no sense?
 
Mar 18, 2009
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FrankDay said:
in this context another term that could be used in place of analysis could be thinking. You may as we'll have said "No thinking - not my game and you know it. " Yet, despite choosing to not think about this stuff you have no qualms about coming here and criticizing those who have tried to think about (analyze) this stuff.

And how is it that you come on to this thread and call others a bully, myself included, with archetypical bully behaviour such as this?

Trying to bully me is a sad technique to cover up your inadequacies. You may think about this stuff, but how you think about it, like your proof of PCs working as claimed, is lacking. You obviously had not thought about the ankle joint and the gastrocnemius muscle otherwise you would not have been so ignorant and myopic to not discuss their contributions to efficiency and power. You can pontificate as much as you like about how much you think about these topics, but others have actually produced something much more substantial than your pathetic musings:

Sanderson et al: Gastrocnemius and soleus muscle length, velocity, and EMG responses to changes in pedalling cadence. J Electromyogr Kinesiol 16: 642-649, 2006.

Gregor RJ, Conconi F: Handbook of Sports Medicine and Science: Road Cycling. "Major ankle extensors are also active during the propulsive phase and, while not considered major power producers, are important in providing a stable link between the pedal, the foot, and the more proximal joints, hip and knee. These ankle extensors ensure that the total amount of energy produced in the lower-extremity musculature can be transmitted to the pedal. ... Force enhancement may occur in these muscles due to the presdence of active stretch before muscle shortening for both the gastrocnemius and soleus muscles. Additionally, the tibialis anterior ... is active during the propulsive phase in many individuals ... and may be used to enhance ankle stability during propulsion and force transmission to the pedal."

D1ck & Wakeling: The functional role of the medial gastrocnemius during cycling: a workloop approach. ABSWEB Conference, 2013. "Our results indicate that the medial gastrocnemius muscle belly transmits power during the down-stroke, and can also act as a motor: the second rise in force during the pedal revolution (at short belly lengths) is characteristic of all loops and likely contributes to knee flexion, pulling up on the crank arm and bringing the pedal back to TDC."

D1ck & Wakeling: Motor or transmission: The functional role of the human gastrocnemii as assessed by 3D ultrasound. "Workloops for all 7 conditions showed a net positive work done by the medial gastrocnemius (MG) and lateral gastrocnemius (LG) muscle belly. MG and LG produced the greatest work at 40 N m (highest crank torque) as dictated by the area within the loop. Positive MG muscle power increased with increasing speed but not increasing crank torque. Tendon stretch for nearly all conditions displays a bimodal pattern, suggesting the gastrocnemii function during both pedal down and up-stroke. It is unknown whether the MG, a bi-articular muscle, functions to transfer the power generated from the large upper leg muscles to the crank during downstroke or generate power to act as a motor. Our results indicate that the MG acts as a transmission element during high loads, transferring power from the more powerful upper leg muscles but can also act as a motor during high speed tasks to produce positive work."

Burke: High Tech Cycling, 2003: the gastrocnemius muscle is a biarticular muscle resulting in knee flexion and ankle extension and "appear to be active to transfer energy between joints at critical times in the pedaling cycle, much like guidewires in a multilink system"

More musings than published work from http://hubpages.com/hub/Muscles-groups-used-while-cycling: the third power phase of the cyclist's pedal stroke is due to the gastrocnemius muscle.

ScreenShot2014-09-05at41547PM_zps8e8e2f66.png


My statement that focusing too closely on a subject and disregarding the bigger picture can result in errors was meant as advice. However, knowing that no one can give you advice that you would heed, it is obvious that this statement applies directly to you.
 
Sep 23, 2010
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FrankDay said:
One more observation regarding your muscle use illustration Hugh
012107pedalstroke.jpg

Notice the hip flexors are shown being used between about 9-11 but for most the knee keeps going up until the foot is about at 1:30. How is that possible without passive movement? So, it is not possible, according to you, for the knee to extend from 3-6, without active contraction, but your own chart shows the knee continuing to rise without any active contraction. Why is one possible and the other not? According to your "analysis" it is ok to push the thigh up passively but not let the knee extend passively. Don't you think it about time you started to seriously think about some of the stuff you have accepted as true just because some "expert" said it was so because your position here is both contradictory and makes no sense?
one more "problem" with your chart. It refers to work being done by the muscles and implies that the work being done by the gastrocnemius is additive to the work being done by the quads and glutes on the downstroke. Unfortunately muscle work requires muscle shortening and for most on the downstroke the calf is contracting isometrically (or contracting eccentrically - lengthening) so is doing no work so is actually not adding to the power. That chart is looking at the energy cost/contractile force of the muscles but does not represent the work done.

Like I said, it would be nice if you would actually put on you thinking cap before spouting off on this stuff so we could have a reasonable discussion as to what is better and what is possible and what is not.
 
Nov 25, 2010
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The important consideration about muscle use in cycling is -
How the contraction affects torque and tangental force.

Because the foot is constrained by being attached to the pedal and forced to move in a circle, the full force of muscle contraction is not likely to be fully tangental - but it still can be providing some additional torque.

So a balance needs to be found between maximum positive force production and efficient use of the muscles to achieve the needed endurance.

The most efficient muscle use might give plenty of endurance, but at the expense of power production.

Jay Kosta
Endwell NY USA
 
Sep 23, 2010
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elapid said:
And how is it that you come on to this thread and call others a bully, myself included, with archetypical bully behaviour such as this?
i can see why you might think me a bully for pointing out that you are here arguing even though you choose to not analyze the argument of the other side. LOL
Trying to bully me is a sad technique to cover up your inadequacies. You may think about this stuff, but how you think about it, like your proof of PCs working as claimed, is lacking. You obviously had not thought about the ankle joint and the gastrocnemius muscle otherwise you would not have been so ignorant and myopic to not discuss their contributions to efficiency and power. You can pontificate as much as you like about how much you think about these topics, but others have actually produced something much more substantial than your pathetic musings:
of course I have thought about the ankle joint, one simple way to look at just how unimportant the ankle joint is is to compare the power generated by someone with a below the knee amputation to "normal" people. Link while amputees do have a loss of power compared to normal this is best explained by an overall loss in leg strength not from ankle issues.
The force asymmetry of CTA is more than twice that of intact cyclists and may be explained by documented
strength imbalance between limbs for persons with ampu- tation (Croisier et al., 2001; Isakov et al., 1996; Pedrinelli et al., 2002). Loss of the ankle joint and the muscles that control it could account, in part, for the strength imbal- ance. Atrophy of proximal muscles has been documented (Schmalz et al., 2001) and indirectly measured in this study as a difference in thigh circumferences. Consider- ing the thigh of the amputated side is smaller, and that the prosthesis has less mass than the limb it replaced, one should assume there are differences in the inertial properties of each limb. These results, combined with results from other studies (Croisier et al., 2001; Isakov et al., 1996; Pedrinelli et al., 2002; Schmalz et al., 2001), may explain most of the differences in force asymmetry given the limitations of these data.
the question isn't whether muscles like the the gastrocnemius are used during cycling, they are. The gastrocnemius must contract to fix the ankle because the forces from the larger upper leg muscles are wasted unless they can be transmitted across the ankle joint. But, unless the gastrocnemius actually shortens it is actually doing no work or providing any additional power. Let the larger muscles do most of the work and simply use the smaller muscle to transmit that work. The fixing function of the gastrocnemius can be substituted by either an ankle fixation device or by moving the cleat placement under the heel (making the lever arm length zero) reducing overall energy cost and improving efficiency. Figuring out these forces is a relatively simple engineering problem. Figuring out what would be optimal is much more difficult.
ScreenShot2014-09-05at41547PM_zps8e8e2f66.png


My statement that focusing too closely on a subject and disregarding the bigger picture can result in errors was meant as advice. However, knowing that no one can give you advice that you would heed, it is obvious that this statement applies directly to you.
I might be more inclined to listen to your "advice" if there were actually any basis for it. What is your engineering background? What is your PowerCranks experience?

Work is a vector which means it has direction and is nothing more than a force applied in a certain direction for a certain distance. Work done in a certain amount of time is power. Applying a force in a direction opposite to the direction of motion results in a loss of power. Why anyone would argue this is an advantage or power increase boggles the mind but you folks are here doing it over and over and then patting each other on the back telling yourselves how smart you are (and telling the world how dumb I am because I don't understand your view). You know what they say, ignorance is bliss
 
Sep 23, 2010
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JayKosta said:
Because the foot is constrained by being attached to the pedal and forced to move in a circle, the full force of muscle contraction is not likely to be fully tangental - but it still can be providing some additional torque.
If the muscle is providing additional torque then it will shorten and the joint angle will change. If the joint angle doesn't change then the muscle adding nothing to the power generated by the other muscles and can be seen as simple as costing energy while doing no work. For any given muscle force the energy cost is much less when contracting isometrically than when contacting eccentrically or concentrically. Hence, it is probably more efficient to fix the ankle joint then to try to provide additional power from these smaller muscles.
 
Mar 18, 2009
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FrankDay said:
I might be more inclined to listen to your "advice" if there were actually any basis for it. What is your engineering background? What is your PowerCranks experience?

Work is a vector which means it has direction and is nothing more than a force applied in a certain direction for a certain distance. Work done in a certain amount of time is power. Applying a force in a direction opposite to the direction of motion results in a loss of power. Why anyone would argue this is an advantage or power increase boggles the mind but you folks are here doing it over and over and then patting each other on the back telling yourselves how smart you are (and telling the world how dumb I am because I don't understand your view). You know what they say, ignorance is bliss

This is not about engineering or who uses PCs. Why do you need to be an engineer to understand muscle forces and physics? I definitely do not need to use PCs to know that you are full of it. You were discussing power and efficiency. You disregarded the ankle joint and the gastrocnemius muscle and I just simply highlighted your error. I don't need to be an engineer to know that you were being shortsighted, myopic and ignorant to disregard the ankle joint and gastrocnemius muscle. While the gastrocnemius muscle may not provide much power compared to the hip extensors and quads, it still does contribute to the power generated during pedalling, as shown by the references provided. The gastrocnemius muscle must shorten because it is a biarticular muscle crossing both the knee and ankle joints and resulting in knee flexion and ankle extension. As shown in the previous diagram, the gastrocnemius muscle shortens from approximately 5 to 6 o'clock and by doing so is responsible for some of the power generated during pedalling. Moreover, the gastrocnemius muscle, with the ankle joint, are essential for efficiency and the transmission of power to the pedal; and I do believe we were discussing both power AND efficiency.
 
Sep 23, 2010
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elapid said:
This is not about engineering or who uses PCs. Why do you need to be an engineer to understand muscle forces and physics?
i guess you don't need to be a trained engineer. But, one has to learn this somewhere. You and I both went to medical school and I don't remember the physics of power generation ever being addressed at my school. Perhaps your school was different. However, I do remember that being addressed when I was graduating with a major in Applied Science at one of the top engineering schools in the country and during the 18 months of post graduate education becoming qualified to run a submarine nuclear reactor and power plant. I would be very interested in knowing where you were taught that applying a force in a direction opposite of the way you are moving can improve power.
I definitely do not need to use PCs to know that you are full of it.
Are you sure you want to keep emphasizing the fact you have zero experience with this tool you seem to know so much about what it can or cannot do?
You were discussing power and efficiency. You disregarded the ankle joint and the gastrocnemius muscle and I just simply highlighted your error. I don't need to be an engineer to know that you were being shortsighted, myopic and ignorant to disregard the ankle joint and gastrocnemius muscle. While the gastrocnemius muscle may not provide much power compared to the hip extensors and quads, it still does contribute to the power generated during pedalling, as shown by the references provided. The gastrocnemius muscle must shorten because it is a biarticular muscle crossing both the knee and ankle joints and resulting in knee flexion and ankle extension. As shown in the previous diagram, the gastrocnemius muscle shortens from approximately 5 to 6 o'clock and by doing so is responsible for some of the power generated during pedalling.
now let me get this straight, you think the fact that the gastrocnemius muscle slightly shortens between 5-6 shows it is responsible for some power generation (because it is a biarticular muscle that FLEXES the knee and plantar flexes the ankle) when between 5 and 6 the knee is most likely still extending and plantar flexion of the ankle should result in a force mostly perpendicular to the direction of motion. But, let's assume the knee is flexing here do you think this could possibly be associated with the thigh slowing down from the glutes relaxing increasing the distance from the knee to the pedal as opposed to the gastrocnemius powerfully flexing the knee. Either way, you are admitting that, at best, this is a small contribution. It seems to me that you are simply grasping at straws here so you don't have to admit you were wrong about everything in this area.
Moreover, the gastrocnemius muscle, with the ankle joint, are essential for efficiency and the transmission of power to the pedal; and I do believe we were discussing both power AND efficiency.
We do agree on this although I suspect our understanding as to why this is true is different. i believe it is because without the gastrocnemius (and tibialis anterior) muscles it would not be possible to "fix" the joint to allow the forces generated by the larger muscles of the leg to be efficiently transmitted across the ankle joint to the pedal. One can only imagine what you think is going on.
 
Nov 25, 2010
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FrankDay said:
If the muscle is providing additional torque then it will shorten and the joint angle will change.
...
=====================================
But consider the situation of a muscle 'attempting' to contract, but being forced to lengthen.
Sitting on a chair with thigh horizontal and lower leg vertical, press down with the heel (while keeping calf muscles relaxed) and slide the heel forward while still exerting downward force.
If the floor was not stationary, the downward force would result in downward power even though the joint angle of the knee is increasing and the angle of the upper leg/hip is decreasing.

The productive force on the pedal is the net 'tangental sum' of all the force vectors being applied to the pedal as it moves through a rotation.

Jay Kosta
Endwell NY USA
 
Mar 18, 2009
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FrankDay said:
i guess you don't need to be a trained engineer. But, one has to learn this somewhere.

I am glad you have accepted that not having a degree in a certain profession means that you cannot have an educated opinion on this topic. If this were true, then you would not be here considering you do not have a degree in exercise physiology and yet you continue to tell all the exercise physiologists on this thread that they are wrong.

FrankDay said:
I would be very interested in knowing where you were taught that applying a force in a direction opposite of the way you are moving can improve power.

Stop trolling. The gastrocnemius muscle contributes to the generation of forces during pedalling between 5-6 o'clock. The gastrocnemius contributes to forces these because of muscle contraction following extension of the muscle bellies during extension (not flexion, as you trollingly stated in your post) of the knee during the downstroke. You have admitted to it, and this is not only my view but also supported by published papers. You are just deflecting because you ignored the role of the ankle joint and gastrocnemius muscle in power and efficiency during pedalling and your myopic and ignorant view was exposed. What you continue to ignore is how essential the lower limb muscles and ankle are to cycling efficiency because these are required for the transmission of forces to the pedal. Why do you continue to deny the role of the lower leg and ankle in pedalling efficiency?
 
Sep 23, 2010
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elapid said:
I am glad you have accepted that not having a degree in a certain profession means that you cannot have an educated opinion on this topic. If this were true, then you would not be here considering you do not have a degree in exercise physiology and yet you continue to tell all the exercise physiologists on this thread that they are wrong.
LOL. I find it amusing that the exercise physiologists here seem to think they know more about cardiac physiology and oxygen delivery to tissue than an anesthesiologist. I am surprised you, a physician, would hold that view also. Just because the words exercise and physiologist is in their title does not make them the de facto expert regarding everything in physiology or in exercise. You might be surprised to learn that most of the time during that 3 year anesthesia residency is spent trying to better understand oxygen delivery physiology and how to manipulate it and not spent learning how to knock people out (anesthesiologist are paid to wake people up under the most difficult of circumstances, not put them to sleep). I put my expertise in this area up against theirs any day. And, if you were smart, you wouldn't bet against me.
Stop trolling. The gastrocnemius muscle contributes to the generation of forces during pedalling between 5-6 o'clock. The gastrocnemius contributes to forces these because of muscle contraction following extension of the muscle bellies during extension (not flexion, as you trollingly stated in your post) of the knee during the downstroke. You have admitted to it, and this is not only my view but also supported by published papers.
I really don't understand what you are talking about here and what I have admitted? Even though I know you aren't into "analysis" but you might want to try this: put you bike on a trainer and one pedal at 6 o'clock then unclip the foot. Now, contract the gastrocnemius on this foot and tell me what happens. Does the cleat move below the pedal or behind (your results may vary depending on your bike fit)? For a muscle to provide any power directly to the bike the direction of motion must in the direction of motion of the pedal, here backwards. I think you will find that gastrocnemius contraction here results mostly in the cleat moving down, not back. If there is any rearward component it is indeed going to be tiny compared to the whole. I look forward to your showing me how I am wrong.
You are just deflecting because you ignored the role of the ankle joint and gastrocnemius muscle in power and efficiency during pedalling and your myopic and ignorant view was exposed. What you continue to ignore is how essential the lower limb muscles and ankle are to cycling efficiency because these are required for the transmission of forces to the pedal.
ugh, I said that in my last answer. What you don't understand is these muscles do not actually provide much, if any, power. The lower leg muscles only fix the ankle joint that allows the power from the bigger muscles of the upper leg to be efficiently transmitted to the pedal. If the ankle were fused little would be lost in power.
Why do you continue to deny the role of the lower leg and ankle in pedalling efficiency?
i don't. I was doing a power analysis and for that analysis it is reasonable to simplify the problem by ignoring the ankle. You are the one who is ignoring the issue of why it is useful to be contacting the quads past 3 o'clock. This is a major issue
 
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JayKosta said:
=====================================
But consider the situation of a muscle 'attempting' to contract, but being forced to lengthen.
Sitting on a chair with thigh horizontal and lower leg vertical, press down with the heel (while keeping calf muscles relaxed) and slide the heel forward while still exerting downward force.
If the floor was not stationary, the downward force would result in downward power even though the joint angle of the knee is increasing and the angle of the upper leg/hip is decreasing.
if I understand you correctly you do not understand. Power is the rate of doing work. Work requires movement in the direction of the force. It doesn't matter how hard one pushes into a floor because the floor can't move no work can be done in this direction so the downward power is zero
The productive force on the pedal is the net 'tangental sum' of all the force vectors being applied to the pedal as it moves through a rotation
while the forces on the pedal are the result of all the muscular (and gravitational) forces acting on it the only force that counts regarding power generation is the component of the resulting total force in the direction of pedal motion at that moment. It is why contracting the quads after 3 o'clock is such a dumb idea.
 
Mar 18, 2009
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FrankDay said:
LOL. I find it amusing that the exercise physiologists here seem to think they know more about cardiac physiology and oxygen delivery to tissue than an anesthesiologist. I am surprised you, a physician, would hold that view also. Just because the words exercise and physiologist is in their title does not make them the de facto expert regarding everything in physiology or in exercise.

Then why do you claim that I cannot understand this topic because I am not an engineer? And what does cardiac physiology and oxygen delivery to tissue have to do with power and efficiency provided by the gastrocnemius muscle and the ankle joint?

FrankDay said:
And, if you were smart, you wouldn't bet against me.

I am smart and I would bet against you most days considering your track record and the track record of recognized specialists in this field who continue to disagree with you in most aspects.

FrankDay said:
Even though I know you aren't into "analysis" but you might want to try this: put you bike on a trainer and one pedal at 6 o'clock then unclip the foot. Now, contract the gastrocnemius on this foot and tell me what happens. Does the cleat move below the pedal or behind (your results may vary depending on your bike fit)? For a muscle to provide any power directly to the bike the direction of motion must in the direction of motion of the pedal, here backwards. I think you will find that gastrocnemius contraction here results mostly in the cleat moving down, not back. If there is any rearward component it is indeed going to be tiny compared to the whole. I look forward to your showing me how I am wrong. ugh, I said that in my last answer. What you don't understand is these muscles do not actually provide much, if any, power.

I agree that they don't provide much power compared to the hip flexors and the quads. Stated very plainly in at least two previous posts. However, they do provide some of the power generated during pedalling. Moreover, you are still ignoring efficiency and efficiency pertains to your original question:

FrankDay said:
There are two major joints between the hip and the pedal, the hip joint and the knee joint ... would this be helpful or hurtful to my desire to generate power or to use my muscles efficiently?

The ankle joint cannot be fixed in position unless surgically arthrodesed because of the biarticular gastrocnemius muscle. So using the ankle being in a fixed position as an argument against the role of the gastrocnemius muscle and ankle in pedalling efficiency is a mute point because 99%+ of cyclists do not have a fused ankle joint. All studies done on the role of the gastrocnemius muscle show its importance in pedalling efficiency. Again, your question specifically stated power AND efficiency, and your assessment that the lower leg muscles and ankle are not major players in power and particularly efficiency are plainly wrong, especially if your only argument against pedalling efficiency is an anatomically impossible scenario unless the ankle joint is fused.
 
Sep 23, 2010
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elapid said:
Then why do you claim that I cannot understand this topic because I am not an engineer?
i don't say that because you are not an engineer, I say that because you don't understand it. It is just if you were an engineer you would.
And what does cardiac physiology and oxygen delivery to tissue have to do with power and efficiency provided by the gastrocnemius muscle and the ankle joint?
nothing. That has to do with the deficiencies in the knowledge base of the average exercise physiologist (at least those that hang out here) since you brought it up.
...

The ankle joint cannot be fixed in position unless surgically arthrodesed because of the biarticular gastrocnemius muscle. So using the ankle being in a fixed position as an argument against the role of the gastrocnemius muscle and ankle in pedalling efficiency is a mute point because 99%+ of cyclists do not have a fused ankle joint. All studies done on the role of the gastrocnemius muscle show its importance in pedalling efficiency. Again, your question specifically stated power AND efficiency, and your assessment that the lower leg muscles and ankle are not major players in power and particularly efficiency are plainly wrong, especially if your only argument against pedalling efficiency is an anatomically impossible scenario unless the ankle joint is fused.
actually, the ankle joint can be fixed externally, that is what a cast or splint can do. The only reason to mention this is to illustrate how little actual power these muscles provide. My simplification, which ignored the ankle joint, of course requires the assumption that the lower leg muscles function to stabilize the ankle joint to maintain efficiency. That is a reasonable assumption and I would have thought went without saying until running into a nit-picker such as you. Simplifications are supposed to be simple to help make the point one is trying to make more easily understandable. This approach obviously failed with you.
 
Mar 10, 2009
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FrankDay said:
This little experiment can be done at each point around the entire circle and you can see what is beneficial and what is not at each point of the circle. Keep in mind that muscle contractions and relaxations must start somewhat before optimum because of normal physiological delays between starting contraction and reaching full force. I look forward to someone explaining to me why there is an advantage to forcibly contracting the quads beyond 3 o'clock on the pedaling circle.

Why (for most riders) does peak torque occur after 3 o'c ?
 
Sep 23, 2010
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coapman said:
Why (for most riders) does peak torque occur after 3 o'c ?

That would be explained if the peak force from the glutes occurred after 3. How the torque is distributed depend on the weight of the various leg parts (gravity) and the force and timing of the various muscles.