The pedaling technique thread

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Got to hand it to you Noel, you never give up.
This one seemed really promising for your side and perplexing to me initially. I know Dr. Ettema and he's a solid scientist who trained under Sjøgaard. The issue with this study finally came to me when I was reading the discussion and he was talking about conservation of kinetic energy. "From a power balance standpoint, the athlete does not fully maintain the amount of external kinetic energy (i.e., energy related to the velocity relative to the environment) by generating the same power that is lost due to external resistance."
While this is true the effect is minuscule in a moving bike and in a stationary bike with a high inertia flywheel. So that got me to looking more carefully at the methods. They used a Tacx; I-Magic trainer with a small flywheel. So yes, if you are on a trainer with little or no kinetic energy storage the cranks will slow down at the deadspots. Thus, as their data indicate it might be beneficial to minimize the deadspot to keep the cranks moving somewhat fluidly. In fact, one wind trainer brand boasts that it has no momentum (kinetic energy) and that forces you to pedal through the deadspot.
But other studies with realistic kinetic energy show the opposite.
Keep trying!
Jim




backdoor said:
 
Jun 4, 2015
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PhitBoy said:
Got to hand it to you Noel, you never give up.
This one seemed really promising for your side and perplexing to me initially. I know Dr. Ettema and he's a solid scientist who trained under Sjøgaard. The issue with this study finally came to me when I was reading the discussion and he was talking about conservation of kinetic energy. "From a power balance standpoint, the athlete does not fully maintain the amount of external kinetic energy (i.e., energy related to the velocity relative to the environment) by generating the same power that is lost due to external resistance."
While this is true the effect is minuscule in a moving bike and in a stationary bike with a high inertia flywheel. So that got me to looking more carefully at the methods. They used a Tacx; I-Magic trainer with a small flywheel. So yes, if you are on a trainer with little or no kinetic energy storage the cranks will slow down at the deadspots. Thus, as their data indicate it might be beneficial to minimize the deadspot to keep the cranks moving somewhat fluidly. In fact, one wind trainer brand boasts that it has no momentum (kinetic energy) and that forces you to pedal through the deadspot.
But other studies with realistic kinetic energy show the opposite.
Keep trying!
Jim




backdoor said:
http://strongbyscience.net/2017/05/26/muscle-slack/
 
Re: Re:

PhitBoy said:
So that got me to looking more carefully at the methods. They used a Tacx; I-Magic trainer with a small flywheel. So yes, if you are on a trainer with little or no kinetic energy storage the cranks will slow down at the deadspots.
Which is exactly what this study demonstrated, see figure 5 for charts plotting the typical crank velocity variation when using a trainer with low crank inertial load, in this case a CycleOps Powerbeam Pro trainer.

http://tinyurl.com/qapfoek

 
Jun 4, 2015
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PhitBoy said:
Got to hand it to you Noel, you never give up.
This one seemed really promising for your side and perplexing to me initially. I know Dr. Ettema and he's a solid scientist who trained under Sjøgaard. The issue with this study finally came to me when I was reading the discussion and he was talking about conservation of kinetic energy. "From a power balance standpoint, the athlete does not fully maintain the amount of external kinetic energy (i.e., energy related to the velocity relative to the environment) by generating the same power that is lost due to external resistance."
While this is true the effect is minuscule in a moving bike and in a stationary bike with a high inertia flywheel. So that got me to looking more carefully at the methods. They used a Tacx; I-Magic trainer with a small flywheel. So yes, if you are on a trainer with little or no kinetic energy storage the cranks will slow down at the deadspots. Thus, as their data indicate it might be beneficial to minimize the deadspot to keep the cranks moving somewhat fluidly. In fact, one wind trainer brand boasts that it has no momentum (kinetic energy) and that forces you to pedal through the deadspot.
But other studies with realistic kinetic energy show the opposite.
Keep trying!
Jim




backdoor said:
I see that study as another waste of research time. What if the application of maximal torque at TDC was brought into the calculation ?

" The lowest work rate (average of top and bottom DC work rate) divided by the average work rate was defined as DC. Thus, this is a parameter describing the evenness of work rate generation; 100% means a perfect circular work rate generation, while 0% indicates that the work rate at the DC equals zero "
 
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Alex Simmons/RST said:
Come back when you have some data Noel.
https://tritrainingharder.com/blog/2015/12/what-makes-pedal-stroke-smooth.html

This man's idea of smooth pedalling is on the right track but needs a few adjustments. For the smoothest possible powerful pedalling over 180 deg. with each leg, the driving force has to start at 330 deg. (11 o'c) and end at 150 deg. (5 o'c). Using both legs this will give the smoothest possible chain drive power from the chainring to the chain.
There also should be no gap or overlap because this can only be done by a simultaneous switchover of crank force application from one leg to the other.
 
Jun 18, 2015
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I love that you come up with all this complicated nonsensical claptrap but when given a solid research paper you respond with "Thanks for the paper, it was too complicated for me to fully understand. "
With your passion for science denial and complex nonsense, perhaps you could get rich as a right-wing climate change denier.

backdoor said:
Alex Simmons/RST said:
Come back when you have some data Noel.
https://tritrainingharder.com/blog/2015/12/what-makes-pedal-stroke-smooth.html

This man's idea of smooth pedalling is on the right track but needs a few adjustments. For the smoothest possible powerful pedalling over 180 deg. with each leg, the driving force has to start at 330 deg. (11 o'c) and end at 150 deg. (5 o'c). Using both legs this will give the smoothest possible chain drive power from the chainring to the chain.
There also should be no gap or overlap because this can only be done by a simultaneous switchover of crank force application from one leg to the other.
 
Jun 4, 2015
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PhitBoy said:
I love that you come up with all this complicated nonsensical claptrap but when given a solid research paper you respond with "Thanks for the paper, it was too complicated for me to fully understand. "
With your passion for science denial and complex nonsense, perhaps you could get rich as a right-wing climate change denier.
Yes, a solid research paper, but what does a cyclist gain from it ? TT pedalling is not about maximizing power from the muscles, it's about maximizing sustainable power. So the important question is, how do you switch your pedalling style from maximal power to one that will supply maximal sustainable power.
 
Jun 4, 2015
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PhitBoy said:
I love that you come up with all this complicated nonsensical claptrap but when given a solid research paper you respond with "Thanks for the paper, it was too complicated for me to fully understand. "
With your passion for science denial and complex nonsense, perhaps you could get rich as a right-wing climate change denier.

" The simulations also provide insights into biarticular muscles by demonstrating that the powers at
each joint spanned by a biarticular muscle can be substantially greater than the net power
produced by the muscle."

Yes it was very complicated for a person with little or no knowledge of physiology and meant a lot of Google searching. From my search it appears that by making maximal use of the lower leg biarticular muscle around TDC ( impossible with natural pedalling ), most resultant force will come from the ankle to the crank. As for climate change, reopening old coal mines is not going to improve the situation.
 
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JayKosta said:
Alex Simmons/RST said:
...
That's not the limiter to TT power output. Ability to generate/regenerate a supply of ATP is the limiter. There's no free lunch.
-----------------
I agree! The 'pedaling technique' issue is about how to maximize the net power that can be generated (possibly along with aerodynamic concerns) with the amount of ATP that is available.

A 'big question' is whether the conventional pedaling style makes best use of the muscles and ATP. Perhaps someone can do a thoughtful examination of the 'muscle usage' details in the paper and see an opportunity to STOP using muscles when they don't produce a worthwhile amount of power for their ATP consumption, and to START using muscles (and joint angles) that would be more effective in power production. It would be a big advance if the 'simulated work loops' modeling can be used proactively to suggest / recommend ways in which the muscles can be used to produce better results.

Jay
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4894017/

" Abstract
The extremities of the human body contain several bi-articular muscles. The actions produced by muscles at the joints they cross are greatly influenced by joint moment arms and muscle length. These factors are dynamic and subject to change as joint angles are altered. Therefore, to more completely understand the actions of such muscles, the angles of both joints must be manipulated. This report reviews investigations, which have explored the actions of two bi-articular muscles of the lower extremities (gastrocnemius and rectus femoris) as the joints they cross are moved into various combinations of angles. The findings have both clinical and physical performance ramifications.
Introduction
Bi-articular muscles are commonly found in the upper and lower extremities of the human body. These muscles generally cross two joints and influence movement at both. The rectus femoris (RF) spans the hip and knee, and the gastrocnemius (GA) crosses the knee and ankle. The actions of these muscles at their primary joints have been known for well over 100 years. The RF is an extensor of the leg, and the GA is a powerful plantarflexor. The descriptions of these particular actions have been relatively unchanged for many years and appear in most anatomy textbooks. However, these muscle action descriptions do not consider the influence the second joint may have on the muscle’s action at the primary joint, or vice versa. For example, considering the GA action at the ankle, how does the plantarflexion (PF) torque it generates change as the angles of the knee and ankle change? At what combination does muscular insufficiency arise? Advances in technology have made it possible to answer questions of this type, resulting in more detailed descriptions of the bi-articular muscles of the extremities. In our previous papers, we discussed in some detail issues such as muscle tissue, joint moments and moment arms and their effects on bi-articular muscle actions.
GA
The GA is one of 14 muscles that act upon the knee, and nine of these, including the GA are bi-articular. However, the GA is only one of these nine that acts on both the knee and ankle, and the others cross the knee and hip. At the knee, the GAs’ actions oppose those of the quadriceps femoris, acting synergistically with the other primary knee flexors (biceps femoris, semitendinosus, semimembranosus, gracilis, popliteus, and sartorius). But it also belongs to another group of muscles that cross the ankle. It opposes the action of the dorsiflexors (e.g., tibialis anterior, extensor digitorum longus and hallucis longus) and it is a powerful plantar flexor working with other posterior leg muscles (e.g., soleus, tibialis posterior, flexor digitorum and hallucis longus). PF forces can be quite high. It is estimated that young males can generate PF torque ranging between 1,000 to 1,780 N.

The GA consists of two heads arising from the posterior aspects of the femoral condyles. These merge into a common belly that rides on the proximal half of the sural aspect of the leg. It shares an insertion with the soleus on the calcaneus via the achilles tendon. The GA and soleus are collectively referred to as the triceps surae and the innervation is supplied by the tibial nerve entering the proximal segments of the muscles. These two muscles provide approximately 80% of force of PF, which is a principal component to a large portion of the gait cycle and essential to nearly all forms of human locomotion. "
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Instead of using the lower leg as a means of transferring generated power from the knee to the pedal*, the combination of the powerful muscles of the lower and upper leg can replace the dead spot sector with the same torque as that applied between 2-4 o'c. The simple technique of indoor tug o'war is all that's required for this combination of the leg's most powerful muscles. Simulated work loop modeling of the indoor tug o'war technique and its force vectors should give interesting results. When you can get a higher torque return from the same force applied by a natural pedaler, it could be said you are getting a free lunch.
*Jim's findings and conclusion drawn from his latest study on natural pedalling, " Thus, during maximal cycling, humans maximize muscle power at the hip and knee, but the ankle acts to transfer (instead of maximize) power. Given that only the timing of muscle stimulation onset and offset were altered, these results suggest that human motor control strategies may optimize muscle activation to maximize power ".
* "We maximized the power that every muscle produced throughout the pedal cycle and came up with patterns that look almost identical to what cyclists do. That means there is nothing else the muscles can do to produce power in some other technique. Any other technique will be less powerful, not more. The differences we saw at the ankle occur during the middle of the recovery portion of the cycle where an active ankle extension would be counter productive. That is, even though soleus could produce more power during that portion of the cycle, doing so would produce negative power on the crank."
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All natural pedallers completely ignore this most powerful and most fatigue resistant muscle in the leg,

" The action of the calf muscles, including the soleus, is plantar flexion of the foot (that is, they increase the angle between the foot and the leg). They are powerful muscles and are vital in walking, running, and keeping balance. The soleus specifically plays an important role in maintaining standing posture; if not for its constant pull, the body would fall forward.

Also, in upright posture, the soleus is responsible for pumping venous blood back into the heart from the periphery, and is often called the skeletal-muscle pump, peripheral heart or the sural (tricipital) pump.

Soleus muscles have a higher proportion of slow muscle fibers than many other muscles. In some animals, such as the guinea pig and cat, soleus consists of 100% slow muscle fibers. Human soleus fiber composition is quite variable, containing between 60 and 100% slow fibers.

The soleus is the most effective muscle for plantar flexion in a bent knee position *. This is because the gastrocnemius originates on the femur, so bending the leg limits its effective tension. During regular movement (i.e., walking) the soleus is the primary muscle utilized for plantar flexion due to the slow twitch fibers resisting fatigue."
* Which makes it ideal for maximal torque through 12 and 1 o'c.
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By using the interaction of muscles (from hip to ball of foot) and variation of angles at hip, knee and ankle joints, plantar flexion force can be increased and applied in a forward direction at 12 o'c, retaining its force and full tangential effect as it turns downward towards 2 o'c. It's the inclusion of the hip muscles (GM) in the PF force generation that makes PF force adaptable for use in the pedalling technique because apart from increasing the force, it gives the pedaller complete control over its direction.
https://www.youtube.com/watch?v=7hh2DcgpnkU
Pedalling using plantar flexion technique. (180 deg. of torque from each leg, PF force 11-2 o'c, natural force 2-5 o'c). Peak torque is being applied between 1 and 2 o'c

http://www.thebikecomesfirst.com/jacques-anquetil-the-man-the-mystery-the-legend-video/
See 7.30 to 9.15

The feet continue to point down because they have to remain set for their powerful plantar flexor mode which can take effect from 11 o'c, the angle of point down depends on the forward/rearward position on saddle.
 
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Re: Basic physics / biomechanics

PhitBoy said:
backdoor said:
Nothing more than basic secondary education, no professional background.
Thanks for being so honest. I suspect that your educational background is really at the heart of the debate/disconnect throughout this topic.
Several of those of us who are arguing with you have advanced degrees. While that may sound pretentious I'm not saying we have superior knowledge just because of letters behind our name. However, with advanced training comes an understanding of what we do know and what we don't know. Your posts suggest that you don't understand the difference between what you "know" and what you believe. We are presenting research based facts and you responding with your beliefs. Kinda like an atheist arguing with a religious person; the debate goes nowhere.
I get it now.
From page 71
I did say physiologists involved with cycling did not know what their muscles were capable of doing, this excerpt from recent research by Dennis Landin et al. explains why, important information on biarticular muscles was missing from their anatomy text books. It formed the basis of Anquetil's technique. We did not need that information, we succeeded in getting the necessary objectives for our brains to put into action as the muscles applied maximal torque through 12 and 1 o'c.

"The extremities of the human body contain several bi-articular muscles. The actions produced by muscles at the joints they cross are greatly influenced by joint moment arms and muscle length. These factors are dynamic and subject to change as joint angles are altered. Therefore, to more completely understand the actions of such muscles, the angles of both joints must be manipulated. This report reviews investigations, which have explored the actions of two bi-articular muscles of the lower extremities (gastrocnemius and rectus femoris) as the joints they cross are moved into various combinations of angles. The findings have both clinical and physical performance ramifications.
Introduction
Bi-articular muscles are commonly found in the upper and lower extremities of the human body. These muscles generally cross two joints and influence movement at both. The rectus femoris (RF) spans the hip and knee, and the gastrocnemius (GA) crosses the knee and ankle. The actions of these muscles at their primary joints have been known for well over 100 years. The RF is an extensor of the leg, and the GA is a powerful plantarflexor. The descriptions of these particular actions have been relatively unchanged for many years and appear in most anatomy textbooks. However, these muscle action descriptions do not consider the influence the second joint may have on the muscle’s action at the primary joint, or vice versa. For example, considering the GA action at the ankle, how does the plantarflexion (PF) torque it generates change as the angles of the knee and ankle change? At what combination does muscular insufficiency arise? Advances in technology have made it possible to answer questions of this type, resulting in more detailed descriptions of the bi-articular muscles of the extremities."
 
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backdoor said:
Alex Simmons/RST said:
blah blah blah.

Data please Noel. All else is meaningless twaddle.
If Jim used his work loop modeling on this example (below) of how the glutes and quads (together with the lower leg muscles) can be used to generate maximal crank torque at TDC and beyond, you would have your data.

"All Jim has to do in his lab is sit in an office chair fitted with casters, without arm rests, then pressing down with his hands on the front portion of the sides of the seat, with heel raised on a non slip surface, force that chair backwards (single leg action. That is the basic technique and it's when this forward force is applied to a fast moving pedal that you get the perfect high gear TT technique. It will demonstrate how the powerful calf muscles, ankle and plantar flexion can be put to work in pedalling around TDC, and is very different from the kicking action recommended by the experts. As for bike set-up, the bars need to be in a position that would leave your arm resistance line roughly parallel to that forward force application line between 1 and 1.30 when in the drops position. On my trainer bike I use cut down and rejoined normal bars instead of the Scott Rake aero bars. A model for the work loop tool."
https://www.facebook.com/watch/?v=301204007442681

The source of Anquetil's mysterious extra sustainable power in flat time trials. Direct arm resistance from correct setting of bars, cleats and upper body in low aero position will more than double the forward force they are producing, giving equal torque at 12 and 3 o'c.

https://www.youtube.com/watch?v=7hh2DcgpnkU
 
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Alex Simmons/RST said:
backdoor said:
https://www.facebook.com/watch/?v=301204007442681

The source of Anquetil's mysterious extra sustainable power in flat time trials. Direct arm resistance from correct setting of bars, cleats and upper body in low aero position will more than double the forward force they are producing, giving equal torque at 12 and 3 o'c.

https://www.youtube.com/watch?v=7hh2DcgpnkU
:lol:
https://www.youtube.com/watch?v=Xo89M1wtKqM
How far would the forward ' kicking force ' recommended by the experts over TDC get you in that chair race. These chair racers are using this powerful combination of muscles to create a forward force in exactly the same way as competitors use them in the powerful sport of indoor tug o'war. When pedalling, the circular track of the pedal and lower high gear cadence extends the range of this maximal torque beyond 1 o'c, peaking at 1.30 where it merges with natural downward force. The dead spot effect in that chair racing can be almost eliminated by attempting to draw the idling leg back faster than the other leg is applying its force and priming the necessary muscles in the process, which leaves them ready for instant application of max force at switchover of legs. The same objectives are used in Anquetil's technique where drawing back starts at 5 o'c and switchover is attempted at 11. This forward force generating technique is more effective and more sustainable when used in pedalling because cleats eliminate the need for the downward tractive force required for chair racing.
 
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Alex Simmons/RST said:
Pull (or rather push) the other one Noel.

Show some data. You know, that funny stuff called evidence.
Drive is the word not push. Common sense not data is what you need here. The funny stuff churned out over the past 120 years can be found in museums around the world. While engineers and scientists were wasting time trying to eliminate the dead spot sector, Anquetil was amassing his fortune by making maximal use of it in time trials with that simple chair racing technique in which maximal forward force can be driven from the hips.

" Lance's agile, toes down pedaling style may be visually reminiscent of 5 time Tour De France Champion Jacques Anquetil. Cyclingnews discussed Lance Armstrong with Jean-Yves Donor. Mr. Donor covers cycling for Paris daily Le Figaro and is head of the International Association of Cycling Journalists. We asked Donor if the comparison of Lance with Anquetil is appropriate.

"Well, not really," said Donor. "Anquetil was an elegant rider who was really a time trial specialist in his day. His riding style was so smooth he looked like he was just sailing along. Anquetil was very powerful in his rear end, and used this to drive his pedaling, while not moving his upper body." "

The natural mashing childhood technique of all cyclists is so ingrained in their brains and muscles that they are incapable of even considering the idea that an equally powerful combination of muscles could be available for use at TDC.
You can see the evidence below,

" Gizmos, Gagets, Whatchamacallits and Thingamajigs.

Every few years, someone tries to redesign the way a bicycle is pedaled. odd shaped gears and complex looking cranksets abound in the bicycle's history. Yet, as different and exotic as they all may look, each and every one of them is attempting to do the exact same thing; create a smooth, unchanging flow of power to the rear wheel.

The problem is this. A human being's legs aren't made to apply smooth, unchanging power in a circular motion. What they were designed to do is:

Raise the person, and themselves, against gravity, and
move the person forwards.
As a result, some of the muscles evolved to be stronger than others. As a result, when they are called upon to pedal a bike, they cannot move the feet at a constant speed around the pedal stroke the way the pedals do. The result is what cyclists call the "dead spot". "

" Whether you believe BioPace, or any other method worked or not, there is no escaping the fact that none of them really did get rid of the dead spot. Even if you match pedal motion to leg motion perfectly, you will still never be able to apply the same force to the pedals at the dead spot as you can during the up/down stroke for the simple reason that the muscles you must use there are weaker. "
 
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backdoor said:
Alex Simmons/RST said:
backdoor said:
https://www.facebook.com/watch/?v=301204007442681

The source of Anquetil's mysterious extra sustainable power in flat time trials. Direct arm resistance from correct setting of bars, cleats and upper body in low aero position will more than double the forward force they are producing, giving equal torque at 12 and 3 o'c.

https://www.youtube.com/watch?v=7hh2DcgpnkU
:lol:
https://www.youtube.com/watch?v=Xo89M1wtKqM
How far would the forward ' kicking force ' recommended by the experts over TDC get you in that chair race. These chair racers are using this powerful combination of muscles to create a forward force in exactly the same way as competitors use them in the powerful sport of indoor tug o'war. When pedalling, the circular track of the pedal and lower high gear cadence extends the range of this maximal torque beyond 1 o'c, peaking at 1.30 where it merges with natural downward force. The dead spot effect in that chair racing can be almost eliminated by attempting to draw the idling leg back faster than the other leg is applying its force and priming the necessary muscles in the process, which leaves them ready for instant application of max force at switchover of legs. The same objectives are used in Anquetil's technique where drawing back starts at 5 o'c and switchover is attempted at 11. This forward force generating technique is more effective and more sustainable when used in pedalling because cleats eliminate the need for the downward tractive force required for chair racing.
That ineffective powerless kicking style over TDC.
https://www.orca.com/ie-en/community/flash-tips/how-to-improve-your-pedaling-technique-to-go-faster/
 
Jun 4, 2015
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Alex Simmons/RST said:
backdoor said:
Common sense not data is what you need here.
No Noel, data is exactly what is needed. Common sense tells me that.

" Optimal cadence selection during cycling
International SportMed Journal
, Vol. 10 No.1, 2009, pp. 1-15, http://www.ismj.com
Official Journal of FIMS (International Federation of Sports Medicine)
1
ISMJ International SportMed Journal
Review article
Optimal cadence selection during cycling
*1, 2, 3
Dr Chris R Abbiss, PhD,
4
Dr Jeremiah J Peiffer, PhD,
1
Associate Professor Paul B Laursen, PhD

1
School of Exercise, Biomedical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
2
Department of Physiology, Australian Institute of Sport, Belconnen, ACT, Australia
3
Division of Materials Science and Engineering, Commonwealth Scientific and Industrial Research Organisation, Belmont, Vic, Australia
4
Centre of Excellence in Alzheimer’s Disease Research and Care, Vario Health Institute, Edith Cowan University, Joondalup, WA, Australia
Abstract
Cadence or pedal rate is widely accepted as an important factor influencing economy of motion, power output, perceived exertion and the development of fatigue during cycling. As a result, the cadence selected by a cyclist’s could have a significant influence on their performance. Despite this, the cadence that optimises performance during an individual cycling task is currently unclear. The purpose of this review therefore was to examine the relevant literature surrounding cycling cadence in order provide a greater understanding of how different cadences might optimise cycling performance. Based on research to date, it would appear that relatively high pedal rates (100-120 rpm) improve sprint cycling performance, since muscle force and neuromuscular fatigue are reduced, and cycling power output maximised at such pedal rates. However, extremely high cadences increase the metabolic cost of cycling. Therefore prolonged cycling (i.e. road time trials) may benefit from a slightly reduced cadence (~90-100 rpm). During ultra-endurance cycling (i.e. >4h), performance might be improved through the use of a relatively low cadence (70-90 rpm), since lower cadences have been shown to improve cycling economy and lower energy demands. However, such low cadences are known to increase the pedal forces necessary to maintain a given power output. Future research is needed to examine the multitude of factors known to influence optimal cycling cadence (i.e. economy, power output and fatigue development) in order to confirm the range of cadences that are optimal during specific cycling tasks. "

How would you solve that problem, by making it possible to reduce cadence while maintaining a given power output without having to increase pedal force ?
 
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"Abstract
Pedal force effectiveness in cycling is usually measured by the ratio of force perpendicular to the crank (effective force) and total force applied to the pedal (resultant force). Most studies measuring pedal forces have been restricted to one leg but a few studies have reported bilateral asymmetry in pedal forces. Pedal force effectiveness is increased at higher power output and reduced at higher pedaling cadences. Changes in saddle position resulted in unclear effects in pedal force effectiveness, while lowering the upper body reduced pedal force effectiveness. Cycling experience and fatigue had unclear effects on pedal force effectiveness. Augmented feedback of pedal forces can improve pedal force effectiveness within a training session and after multiple sessions for cyclists and non-cyclists. No differences in pedal force effectiveness were evident between summarized and instantaneous feedback. Conversely, economy/efficiency seems to be reduced when cyclists are instructed to improve pedal force effectiveness during acute intervention studies involving one session. Decoupled crank systems effectively improved pedal force effectiveness with conflicting effects on economy/efficiency and performance."

Why is pedal force effectiveness increased at higher power output ?
 
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Why is pedal force effectiveness increased at higher power output ?
Simple. Because most of the ineffective forces come from the mass of the limbs (weight and acceleration) whereas the effective forces come from muscular effort. Those mass-dependent forces remain constant. So as power goes up the mass depended forces represent a smaller contribution to overall forces.
Is that something you can understand Noel?
 
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No, I don't understand. I can't see what you describe having much of an effect on performance.
" Pedal force effectiveness in cycling is usually measured by the ratio of force perpendicular to the crank (effective force) and total force applied to the pedal (resultant force). "
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" Decoupled crank systems effectively improved pedal force effectiveness with conflicting effects on economy/efficiency and performance. "

This means both pedal force effectiveness and efficiency can only be improved by increasing force effectiveness where the most powerful muscles can be used.
 
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