For the "pedaling technique doesn't matter crowd"

[coapman]

Edit: The authors report that effectiveness improves but efficiency drops when riders are asked to make this change. But, the real question is what happens to "pedaling effectiveness" and "efficiency" (and power) as riders train themselves to ride in this different fashion for long periods. Until that question is answered (for this and other pedaling techniques) the question as to which technique is best or better than another remains unresolved by science.

What exactly is meant by pedalling effectiveness and pedalling efficiency ?

 

[CoachFergie]

What exactly is meant by pedalling effectiveness and pedalling efficiency ?

Ummmmmm, aren't they the things you are trying to tell us your style of pedalling improves? How can you argue for improved pedalling and not know what effectiveness and efficiency means.

ps. Bwah ha ha ha ha ha ha ha ha ha ha

 

[CoachFergie]

Noel, I see Jim Martin has very generously offered to test your style of pedalling in the Lab in the UK

http://forum.slowtwitch.com/gforum....188;page=3;sb=post_latest_reply;so=ASC;mh=25;

Re: Awful pedal stroke [perfection] [In reply to] Quote | Reply
perfection wrote:I can apply continuous max torque through 12, 1 ,2, and 3 o'c, returning to normal torque through 4 and 5.
Please stop by my lab at University of Utah any time you're in the area so we can document your miraculous pedaling technique.
EDIT: I forgot that we've had this conversation before. You're in UK right? I offered to set up testing for you at Tom Korff's lab at Brunel University in London but you said you don't ever get to London. I could also ask Paul Barratt to have look. He's the biomechanist for British Cycling in Manchester. Maybe that's closer to you. I'm sure they'd like see your technique in action as well.
Cheers,
Jim

Well, this is great news. Now you can prove your theory once and for all. I'm surprised that Frank hasn't taken the opportunity to do the same in California.

 

[coapman]

Ummmmmm, aren't they the things you are trying to tell us your style of pedalling improves? How can you argue for improved pedalling and not know what effectiveness and efficiency means.

ps. Bwah ha ha ha ha ha ha ha ha ha ha

I have my own definitions for pedalling effectiveness and efficiency but when the word 'mechanical' efficiency is added, it gets confusing. Maybe you will enlighten everyone with your coaching definition of all three.

 

[coapman]

Noel, I see Jim Martin has very generously offered to test your style of pedalling in the Lab in the UK

http://forum.slowtwitch.com/gforum....188;page=3;sb=post_latest_reply;so=ASC;mh=25;



Well, this is great news. Now you can prove your theory once and for all. I'm surprised that Frank hasn't taken the opportunity to do the same in California.

I have nothing to prove, it's fact. Unlike Frank I am not in this for money. I don't like the inconvenience of travelling, This semi circular technique can be made available to anyone for testing provided they are prepared to do the travelling.

 

[CoachFergie]

can be made available to anyone for testing provided they are prepared to do the travelling.

As long as it is not you

Pathetic

 

[coapman]

As long as it is not you

Pathetic

Brimbros should be able to supply the proof without anyone having to travel. Still waiting for your 3 definitions.

 

[CoachFergie]

Brimbros should be able to supply the proof without anyone having to travel.

Ha ha, a product which still doesn't have a release date over an offer to meet with a sport scientist and test your delusion.

Pathetic.

 

[coapman]

Ha ha, a product which still doesn't have a release date over an offer to meet with a sport scientist and test your delusion.

Pathetic.

What have sport scientists done to improve pedalling over the past 122 years ? Still waiting for your three definitions.

 

[CoachFergie]

Measured pedalling, determined the optimal pedalling stroke is the natural pedalling stroke, measured alternative's and determined that those who make random claims have no evidence to support them.

Definitions? Google them.

 

[coapman]

Measured pedalling, determined the optimal pedalling stroke is the natural pedalling stroke, measured alternative's and determined that those who make random claims have no evidence to support them.

Definitions? Google them.

I asked for improvements, not for what they had wasted their research time on. As for those definitions, maybe Frank can supply them.

 

[FrankDay]

I asked for improvements, not for what they had wasted their research time on. As for those definitions, maybe Frank can supply them.

Usually, how each author uses any specific term is defined in the paper so that there should not be any confusion amongst the readers.

 

[JayKosta]

Regarding definnitions - my thoughts .....

pedaling efficiency - the percentage of total energy (power) expended that produces positive tangential pedal torque.

'mechanical' pedaling effectiveness - a measure of how constant the rotational speed of the cranks is.
Not just constant rpm, but whether changes in crank speed occur during a complete crank rotation.
This is important because crank speed deceleration and acceleration requires more mechanical energy (and power) than keeping the cranks turning at a constant rate.

'physiological' pedaling effectiveness - this would be a comparison of different pedaling techniques, body position, nutrition, etc. for a single rider to determine what combination gives best results for a particular event / test.

Jay Kosta
Endwell NY USA

 

[coapman]

Edit: The authors report that effectiveness improves but efficiency drops when riders are asked to make this change. But, the real question is what happens to "pedaling effectiveness" and "efficiency" (and power) as riders train themselves to ride in this different fashion for long periods. Until that question is answered (for this and other pedaling techniques) the question as to which technique is best or better than another remains unresolved by science.

In above paragraph what do the words effectiveness and efficiency mean ?

 

[Alex Simmons/RST]

Why complicate an efficiency measure?

Energy delivered to the crank spider as a proportion of energy metabolised. Simple.


And why use misleading and unnecessary terms by including the word efficiency where it doesn't belong?

Crank speed variances might or might not have an influence on efficiency, but calling it an efficiency measure is totally misleading and suggests a causal link between crank speed and efficiency when none has been established (much like all these "pedal efficiency" measures falsely imply a causal link between different in-stroke torque variances and efficiency).

Just call it what it is, i.e. crank speed variance (or peak crank speed to average crank speed ratio, or whatever speed variance measure you like), and then test to see if it has any bearing on actual efficiency, or on performance.

Ironically, non-round rings are specifically designed to vary the crank speed through a pedal stroke, yet are touted as improving pedalling.


Efficiency is nice and all, but at end of the day, if you can't deliver more power for the durations of relevance for your event and when you need it (which is what I'd call effectiveness but it's a redundant term since it's just another way of saying more power), then what's the point?

 

[FrankDay]

In above paragraph what do the words effectiveness and efficiency mean ?

I believe you will find that these authors defined effectiveness as how close the actual pedal force vector is to the current tangential direction averaged around the pedal circle. Efficiency relates to how much energy is delivered to the bicycle chain/wheel compared to how much energy was expended by the rider.

 

[FrankDay]

Why complicate an efficiency measure?

Energy delivered to the crank spider as a proportion of energy metabolised. Simple.


And why use misleading and unnecessary terms by including the word efficiency where it doesn't belong?

Crank speed variances might or might not have an influence on efficiency, but calling it an efficiency measure is totally misleading and suggests a causal link between crank speed and efficiency when none has been established (much like all these "pedal efficiency" measures falsely imply a causal link between different in-stroke torque variances and efficiency).

Just call it what it is, i.e. crank speed variance (or peak crank speed to average crank speed ratio, or whatever speed variance measure you like), and then test to see if it has any bearing on actual efficiency, or on performance.

Ironically, non-round rings are specifically designed to vary the crank speed through a pedal stroke, yet are touted as improving pedalling.


Efficiency is nice and all, but at end of the day, if you can't deliver more power for the durations of relevance for your event and when you need it (which is what I'd call effectiveness but it's a redundant term since it's just another way of saying more power), then what's the point?

Two points. Crank speed is effectively constant regardless of what the rider does or what chain rings they use (except in the case of Rotor cranks where there is a substantial variation between peak upstroke speed and peak downstroke speed). The reason for this is the mass of the bike/rider and bike speed and the pedaling cadence means there is a large momentum, small variations in forces, and little time to affect speed changes such that pedal speed will remain essentially constant. Another time this isn't quite the case is when on the trainer and the mass of the rider is removed from the equation such that the small mass of the wheel allows for noticeable changes in speed (which can be heard in the whir, whir, whir in the wheel) but even these variations are small at normal cadences.

Regarding efficiency. Efficiency becomes more and more important, eventually trumping power, the longer the rider is asked to ride. This is because energy requirements and metabolism (and the need to refuel) is more important in a race like the RAAM and, perhaps, a race like the TDF or, even, an Ironman. Surely power trumps efficiency in a short track race like the sprint or pursuit but at some point as distances increase efficiency becomes equally important and later more important than power since we are limited in our ability to refuel.

 

[coapman]

I believe you will find that these authors defined effectiveness as how close the actual pedal force vector is to the current tangential direction averaged around the pedal circle. Efficiency relates to how much energy is delivered to the bicycle chain/wheel compared to how much energy was expended by the rider.

My definition of pedalling efficiency is the percentage torque return from the force that is applied to the pedal. Pedalling effectiveness I would describe as the number of degrees out of a possible 180 that a rider could apply effective maximal force to the pedal. The difficulty for scientists is they are stuck with the one natural technique and they have nothing to compare except for playing around with variations of the same basic technique.

 

[FrankDay]

My definition of pedalling efficiency is the percentage torque return from the force that is applied to the pedal. Pedalling effectiveness I would describe as the number of degrees out of a possible 180 that a rider could apply effective maximal force to the pedal. The difficulty for scientists is they are stuck with the one natural technique and they have nothing to compare except for playing around with variations of the same basic technique.

Your definition of pedaling efficiency is the same as those authors definition of pedaling effectiveness (if you integrate it around the entire circle). To most scientists efficiency is refers to energy. Unless you use the same definitions you cannot have a discussion with anyone. You ought to try to bring your use of these terms in line with the rest of the world so the world can understand what you are trying to say.

 

[coapman]

Your definition of pedaling efficiency is the same as those authors definition of pedaling effectiveness (if you integrate it around the entire circle). To most scientists efficiency is refers to energy. Unless you use the same definitions you cannot have a discussion with anyone. You ought to try to bring your use of these terms in line with the rest of the world so the world can understand what you are trying to say.

W are discussing pedalling and power application not how the body reacts to it. Over how many degrees of the pedalling circle is your leg capable of applying maximal force to the pedal ?

 

[FrankDay]

W are discussing pedalling and power application not how the body reacts to it. Over how many degrees of the pedalling circle is your leg capable of applying maximal force to the pedal ?

The important thing is not over how many degrees one can apply maximum force to the pedal but what is the average force applied around the entire circle (including the upstroke) since that (when both pedals are added together) is the average power the bike sees and the power a power meter will measure. Your approach is no more worthy than the "just push harder" folks as both of you ignore the rest of the stroke and the power the bike sees is determined by the entirety of the stroke. I mean, really, do you (or anyone in the just push harder group) think it doesn't matter how large the negative forces are on the upstroke as long as you are pushing hard (or hard for a long time) on the downstroke?

In other words, I don't care how many degrees of the pedaling circle I am capable of applying maximum force. I don't care what my peak force is. My main concern is figuring out how to maximize total power delivered or pedaling efficiency or both. I believe that involves both improving "pedaling effectiveness" (getting more power to the bike out of each muscle contraction) and spreading the power application out over as much of the 360º circle as possible even if it is not at "maximum" for much of that circle.

 

[coapman]

The important thing is not over how many degrees one can apply maximum force to the pedal but what is the average force applied around the entire circle (including the upstroke) since that (when both pedals are added together) is the average power the bike sees and the power a power meter will measure. Your approach is no more worthy than the "just push harder" folks as both of you ignore the rest of the stroke and the power the bike sees is determined by the entirety of the stroke.

The difference between my technique and the push harder folk is I push harder for longer over the entire 180 deg., and 90 deg. of this maximal power is giving almost 100 % torque return. Using the (idling) leg in an attempt to increase power output results in an overall loss of power but when you use the idling arm, this situation is reversed. What you are not making clear is, do you attempt to apply power as the pedal rises or do you only unweight in this sector. If you only unweight there, your extra torque can only be applied at the bottom and top of the pedalling circle. From the graph you made available, only minimal torque was applied in these sectors whereas I can apply maximal torque there in addition to the increased efficiency elsewhere.

 

[FrankDay]

The difference between my technique and the push harder folk is I push harder for longer over the entire 180 deg., and 90 deg. of this maximal power is giving almost 100 % torque return. Using the (idling) leg in an attempt to increase power output results in an overall loss of power but when you use the idling arm, this situation is reversed. What you are not making clear is, do you attempt to apply power as the pedal rises or do you only unweight in this sector. If you only unweight there, your extra torque can only be applied at the bottom and top of the pedalling circle. From the graph you made available, only minimal torque was applied in these sectors whereas I can apply maximal torque there in addition to the increased efficiency elsewhere.

Remember, there are 360º to the pedaling circle and the pedal is rising during 180º of that circle. Once the pedal is beyond BDC it is rising until it gets to TDC so anyone trying to "scrape the mud off the shoes" is applying positive force when the pedal is rising even if they are not thinking about "pulling up". Or those like you, because you are starting your "max power" application before TDC are also applying positive force when the pedal is rising even though you are not "pulling up".

I believe that best technique involves "scraping the mud off" well across the bottom and starting the "push over the top" well before the top, and complete unweighting in between, in addition to pushing down with substantial force. Focusing on only a small portion of the circle wastes a lot of potential IMHO.

 

[Alex Simmons/RST]

Two points. Crank speed is effectively constant regardless of what the rider does or what chain rings they use (except in the case of Rotor cranks where there is a substantial variation between peak upstroke speed and peak downstroke speed). The reason for this is the mass of the bike/rider and bike speed and the pedaling cadence means there is a large momentum, small variations in forces, and little time to affect speed changes such that pedal speed will remain essentially constant. Another time this isn't quite the case is when on the trainer and the mass of the rider is removed from the equation such that the small mass of the wheel allows for noticeable changes in speed (which can be heard in the whir, whir, whir in the wheel) but even these variations are small at normal cadences.

Regarding efficiency. Efficiency becomes more and more important, eventually trumping power, the longer the rider is asked to ride. This is because energy requirements and metabolism (and the need to refuel) is more important in a race like the RAAM and, perhaps, a race like the TDF or, even, an Ironman. Surely power trumps efficiency in a short track race like the sprint or pursuit but at some point as distances increase efficiency becomes equally important and later more important than power since we are limited in our ability to refuel.

I agree with both those points although for the latter, if one can produce more power I think they will still take it as it means an ability to ride their target pace at an even lower fraction of their threshold (and further spare glycogen stores). Not sure I'd rate it more important but in any case, efficiency is a factor in such events. I thought I originally had a line in there about ultra endurance events in my earlier post but must have deleted it, probably not wanting to confuse my point.

Back to the crank speed thing though - there are still some small variations and someone measured them on the bike riding, both flat and on hills. Will see if I can locate. It was a discussion where the "micro-accelerations on hills cost you a lot of extra energy" hypothesis needed the Mythbusters treatment.

 

[FrankDay]

I agree with both those points although for the latter, if one can produce more power I think they will still take it as it means an ability to ride their target pace at an even lower fraction of their threshold (and further spare glycogen stores). Not sure I'd rate it more important but in any case, efficiency is a factor in such events. I thought I originally had a line in there about ultra endurance events in my earlier post but must have deleted it, probably not wanting to confuse my point.

I think we are in agreement here. For endurance events we are talking about sustainable power. There is one area where we probably differ. That would go to that study that showed that asking the riders to pull up improved effectiveness but decreased efficiency. I would contend that with enough time training the more effective method of pedaling would eventually result in improved efficiency also. That is what is reasonably concluded from Luttrell. Otherwise, I think the scientist is left with the difficult job of trying to explain why effectiveness and efficiency are not both related to power directly (as opposed to having opposite slopes). It is not enough to hae "results". One also needs a mechanism to explain the results that can be used to make correct predictions.

Back to the crank speed thing though - there are still some small variations and someone measured them on the bike riding, both flat and on hills. Will see if I can locate. It was a discussion where the "micro-accelerations on hills cost you a lot of extra energy" hypothesis needed the Mythbusters treatment.

Of course there are micro-accelerations, that is how spin-scan works. F=ma. I once thought this might play a role in efficiency. I no longer believe this because they are so small they can be effectively ignored.