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Pedalling science (or not, as the case may be!)

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  • 14-12-2010 12:26am
    #1
    learn
    Registered Users Posts: 137 ✭✭


    markdrayton wrote: »
    turbo trainers have very little inertia and exaggerate the dead spot in the pedal stroke

    The truth is ever since cleats, toeclips and straps were introduced into cycling it has been possible to apply even higher maximal torque to the crank as it passes through 12 and 1 o'c than that applied at 3 o'c while in the natural racing drops position. The merging of this maximal forward tangential force with the normal maximal downward tangential force results in the perfect high gear TT pedalling technique. How many would be prepared to bet against that statement.

    Mod Note - moved from the turbo vs road cycle thread


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    #2
    niceonetom
    Registered Users Posts: 4,833 ✭✭✭niceonetom


    learn wrote: »
    The truth is ever since cleats, toeclips and straps were introduced into cycling it has been possible to apply even higher maximal torque to the crank as it passes through 12 and 1 o'c than that applied at 3 o'c while in the natural racing drops position. The merging of this maximal forward tangential force with the normal maximal downward tangential force results in the perfect high gear TT pedalling technique. How many would be prepared to bet against that statement.

    Me, for one.


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    #3
    learn
    Registered Users Posts: 137 ✭✭learn


    niceonetom wrote: »
    Me, for one.


    You should not be so eager to throw away your cash. I had hoped that 'BRIM BROTHERS' force vector powermeter would have been available before now but they appear to have had to go back to their drawing boards. This type of PM is a necessity for verification purposes because the legs move so fast it would be impossible for an onlooker to detect what is actually happening in the muscles or how and where the force is being applied to the cranks. However if you or any innovative minded riders would be interested in a detailed explanation as to how this simple technique operates or in seeing what pedalling without a time wasting 'dead spot' area looks like, I would be willing to give a free demonstration. Unlike all other cycling researchers I am not in this for profit, I get my satisfaction from being able to do what experts have always considered an impossible task.


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    #4
    tunney
    Registered Users Posts: 12,583 ✭✭✭✭tunney


    learn wrote: »
    You should not be so eager to throw away your cash. I had hoped that 'BRIM BROTHERS' force vector powermeter would have been available before now but they appear to have had to go back to their drawing boards. This type of PM is a necessity for verification purposes because the legs move so fast it would be impossible for an onlooker to detect what is actually happening in the muscles or how and where the force is being applied to the cranks. However if you or any innovative minded riders would be interested in a detailed explanation as to how this simple technique operates or in seeing what pedalling without a time wasting 'dead spot' area looks like, I would be willing to give a free demonstration. Unlike all other cycling researchers I am not in this for profit, I get my satisfaction from being able to do what experts have always considered an impossible task.

    FFS is this Frank from powercranks?

    There are other ways to see a breakdown of your pedal stroke showing where you apply power other than Brim Brothers. To give angles of torque, distribution of power and all the rest. I've worked alot on my pedal stroke and there is no way with a proper set up(by that I mean a bike that fits and a position that allows optimal power generation) to get power at 12 to exceed power at 3.

    If billy.fish sees this thread he may have a fit.


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    #5
    Beasty
    Administrators, Social & Fun Moderators, Sports Moderators Posts: 75,770 Admin ✭✭✭✭✭Beasty


    tunney wrote: »
    FFS is this Frank from powercranks?

    Last time you asked him, he said no


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    #6
    tunney
    Registered Users Posts: 12,583 ✭✭✭✭tunney


    Beasty wrote: »
    Last time you asked him, he said no

    Sorry i am repeating myself these days. Must be old age.

    It does sound like a SlowTwitch thread though :)


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    #7
    Lumen
    Registered Users Posts: 31,031 ✭✭✭✭Lumen


    tunney wrote: »
    I've worked alot on my pedal stroke

    Do you think it has made you faster or more efficient?


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    #8
    billy.fish
    Closed Accounts Posts: 671 ✭✭✭billy.fish


    el tel wrote: »
    Was reading today that turbo sessions should be 50% duration of road session.

    I read that the dinosaurs died out because i touch myself at night, dosn't make it right.

    learn wrote: »
    The truth is ever since cleats, toeclips and straps were introduced into cycling it has been possible to apply even higher maximal torque to the crank as it passes through 12 and 1 o'c than that applied at 3 o'c while in the natural racing drops position. The merging of this maximal forward tangential force with the normal maximal downward tangential force results in the perfect high gear TT pedalling technique. How many would be prepared to bet against that statement.

    First off, NEVER start a statement with 'the truth'. Basic principal of science is you cannot prove something, you can only disprove a statement, this however does not make it true. Go look up Socratic method.

    Secondly, applying maximal torque at 12-1...don't be mental. If you want to get into tangential force application ill agree with you ina mechanical system which applies linear power throughout a movement phase. WHen you are working with a physical system you are constrained by lots of things. ROM, sarcomear recruitment, muscle preload, contraction rates, blah blah blah... the force generated by a muscle is not linear and takes a period of time before it recruits enough force to generate maximal force. Add into to this mechanics about the knee and the muscle contraction length change and you get peak forces being developed further on that '1pm' on the pedal stroke clock.

    Thirdly, 'high gear pedalling technique'. What you talking about Willis? Seriously. Just no. If you want to talk about ROPFD you are going about it the wrong way.


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    #9
    billy.fish
    Closed Accounts Posts: 671 ✭✭✭billy.fish


    learn wrote: »
    You should not be so eager to throw away your cash. I had hoped that 'BRIM BROTHERS' force vector powermeter would have been available before now but they appear to have had to go back to their drawing boards. .

    *Anger rising*

    First off Barrys PM is not back to boards, its just not done yet. please stop confucing rumours with reality. (GregisinnowaysupportedbyBB,andhasnointerestinthesystemashehas aniceaccelerometerbasedPMinhislabthatworks)
    learn wrote: »
    This type of PM is a necessity for verification purposes because the legs move so fast it would be impossible for an onlooker to detect what is actually happening in the muscles or how and where the force is being applied to the cranks.

    Go look at an EMG, it does what you are describing, they are used regularly in labs and real world testing. Infact (reaches across desk) here is one...
    learn wrote: »
    However if you or any innovative minded riders would be interested in a detailed explanation as to how this simple technique operates or in seeing what pedalling without a time wasting 'dead spot' area looks like, I would be willing to give a free demonstration. Unlike all other cycling researchers I am not in this for profit, I get my satisfaction from being able to do what experts have always considered an impossible task.

    Not in it for profit....sure. Cause thats not the system the world is built on. Profit is not always defined in monetary terms. Profit for me for example can be a loss in weight, or a gain in notoriety in scientific circles.

    Also, we know what the dead spot looks like, its not impossible, nothing is impossible, thats the whole point of science.

    Tunney, you are right with the Slowbitch feel to this too.


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    #10
    Lumen
    Registered Users Posts: 31,031 ✭✭✭✭Lumen


    https://www.youtube.com/watch?v=0VYP-WB6H50


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    #11
    Jawgap
    Closed Accounts Posts: 20,297 ✭✭✭✭Jawgap


    billy.fish wrote: »
    .........First off, NEVER start a statement with 'the truth'. Basic principal of science is you cannot prove something, you can only disprove a statement, this however does not make it true. Go look up Socratic method.


    .........

    I thought "falsificationism" was Popperian in origin, whereas the Socratic method is more dialetical. And

    Just sayin' like.......


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    #12
    billy.fish
    Closed Accounts Posts: 671 ✭✭✭billy.fish


    Jawgap wrote: »
    I thought "falsificationism" was Popperian in origin, whereas the Socratic method is more dialetical. And

    Just sayin' like.......

    Not certain, studied science not arts ;)

    But in essence in science we say that the only thing that can be proven truthful is through a pure math proof, otherwise is still not a truth even it proven to be incorrect as you can always prove that to be wrong in some circumstances.

    In the end of the day its all about trying to prove things are wrong, not right.


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    #13
    Jawgap
    Closed Accounts Posts: 20,297 ✭✭✭✭Jawgap


    did science too - you must've missed the module on philosophy of science - I figured it was a handy few credits rather than doing something useful for a semester;)

    Anyway, it's all semantics......there is no truth, only knowledge


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    #14
    billy.fish
    Closed Accounts Posts: 671 ✭✭✭billy.fish


    Jawgap wrote: »
    did science too - you must've missed the module on philosophy of science - I figured it was a handy few credits rather than doing something useful for a semester;)

    Anyway, it's all semantics......there is no truth, only knowledge

    Yeah, i kinda worried about the actual science not the faff


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    #15
    DrB
    Banned (with Prison Access) Posts: 12 ✭DrB


    learn wrote: »
    I had hoped that 'BRIM BROTHERS' force vector powermeter would have been available before now but they appear to have had to go back to their drawing boards.
    We're not back to the drawing board - same concept, same design, still beavering away, just the implementation is taking longer than we planned. We're engineers, optimism is part of our genetic makeup (along with pizza, beer and stubbornness).


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    #16
    chakattack
    Registered Users Posts: 1,315 ✭✭✭chakattack


    Hi Dr B,

    Keep up the good work, really looking forward to the finished product (with an introductory special price for boards members? ;) )

    Are you still going with speedplay?

    If you need anyone guinea pigs for testing prototypes........:)


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    #17
    tunney
    Registered Users Posts: 12,583 ✭✭✭✭tunney


    DrB wrote: »
    We're not back to the drawing board - same concept, same design, still beavering away, just the implementation is taking longer than we planned. We're engineers, optimism is part of our genetic makeup (along with pizza, beer and stubbornness).

    With two other pedal based PMs coming next year what features of yours do you see making yours superior to Garmins and Polar/Looks?


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    #18
    uberwolf
    Registered Users Posts: 7,580 ✭✭✭uberwolf


    Jawgap wrote: »
    did science too - you must've missed the module on philosophy of science - I figured it was a handy few credits rather than doing something useful for a semester;)

    Anyway, it's all semantics......there is no truth, only knowledge

    Easy marks, but also very interesting


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    #19
    DrB
    Banned (with Prison Access) Posts: 12 ✭DrB


    tunney wrote: »
    With two other pedal based PMs coming next year what features of yours do you see making yours superior to Garmins and Polar/Looks?
    This is the subject of a short blog post I'm hoping to put together before Christmas, but essentially it's that we're the only one that's fitted to the rider, with nothing fitted to the bike. We can also measure more information about pedal angles and force distribution (which is also part of our implementation challenge - more degrees of freedom to analyse).


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    #20
    Jawgap
    Closed Accounts Posts: 20,297 ✭✭✭✭Jawgap


    uberwolf wrote: »
    Easy marks, but also very interesting


    Very interesting indeed - and actually quite useful as I referee quite a few papers now so I get to apply the concepts!!

    Anyway......back on topic (sort of) - great to see something like Brim Brothers happening in Ireland - maybe the coountry is not f&cked yet:)


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    #21
    learn
    Registered Users Posts: 137 ✭✭learn


    tunney wrote: »
    I've worked alot on my pedal stroke and there is no way with a proper set up(by that I mean a bike that fits and a position that allows optimal power generation) to get power at 12 to exceed power at 3.

    It depends on how you intend to apply your pedal power. In the sport of Tug o'War there are two different types of competition, outdoor (field) and indoor (floor mat) and while the basic objective and generated power is the same, the leg power generating techniques are very different. The outdoor style is similar to that of a natural pedaller as he applies max torque at 3 o'c, while the indoor method is identical to the one I use when applying max torque through 12 o'c. When generating leg muscle power Tug o'War competitors have the advantage of maximal arm resistance, the same applies as I apply max torque through 12 o'c except in my case it is alternate max arm resistance and this results in direct active pedalling resistance while the natural pedaller like yourself has only got the assistance of indirect passive resistance from his body weight as he applies his max torque through 3 o'c . As my pedal returns from 5 to 11 o'c the leg muscles are preset with spring loaded effect ready for simultaneous release of instant maximal torque when the other leg's power application ends at 5 o'c and that is when that special instant max arm resistance takes effect. There you have the explanation.


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    #22
    billy.fish
    Closed Accounts Posts: 671 ✭✭✭billy.fish


    learn wrote: »
    It depends on how you intend to apply your pedal power. In the sport of Tug o'War there are two different types of competition, outdoor (field) and indoor (floor mat) and while the basic objective and generated power is the same, the leg power generating techniques are very different. The outdoor style is similar to that of a natural pedaller as he applies max torque at 3 o'c, while the indoor method is identical to the one I use when applying max torque through 12 o'c. When generating leg muscle power Tug o'War competitors have the advantage of maximal arm resistance, the same applies as I apply max torque through 12 o'c except in my case it is alternate max arm resistance and this results in direct active pedalling resistance while the natural pedaller like yourself has only got the assistance of indirect passive resistance from his body weight as he applies his max torque through 3 o'c . As my pedal returns from 5 to 11 o'c the leg muscles are preset with spring loaded effect ready for simultaneous release of instant maximal torque when the other leg's power application ends at 5 o'c and that is when that special instant max arm resistance takes effect. There you have the explanation.

    No.

    There is no stretch shortening cycle in the pedalling action, there is no eccentric phase before the concentric phase contraction. Sorry. Just no.

    Dont confuse weight bearing actions with non weight bearing actions, the muscular contractions are different.


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    #23
    niceonetom
    Registered Users Posts: 4,833 ✭✭✭niceonetom


    @learn - I'm having trouble visualising what you could possibly mean by "special instant max arm resistance" etc.

    Perhaps you could clarify what you mean by illustration? Or photos? What kind of bike are we talking about here? How big a gear are you pushing? etc.

    Don't be coy.


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    #24
    billy.fish
    Closed Accounts Posts: 671 ✭✭✭billy.fish


    niceonetom wrote: »
    @learn - I'm having trouble visualising what you could possibly mean by "special instant max arm resistance" etc.

    Perhaps you could clarify what you mean by illustration? Or photos? What kind of bike are we talking about here? How big a gear are you pushing? etc.

    Don't be coy.

    I think this image could help:

    crap-detector.jpg


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    #25
    niceonetom
    Registered Users Posts: 4,833 ✭✭✭niceonetom


    Nonsense! I'm sure that learn's extensive research will totally debunk everything you think to be true! Great advances in cycling/tug-o-war technology and sports science like this don't come along every day, you know. It'll be traumatic at first, realising that you've been wrong for so long with all that lab work, but I'm sure it'll be worth it when you experience the speed of "simultaneous release of instant maximal torque" that this breakthrough will allow.

    So c'mon learn. Don't leave us hanging. Prove billy wrong!


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    #26
    billy.fish
    Closed Accounts Posts: 671 ✭✭✭billy.fish


    niceonetom wrote: »
    Nonsense! I'm sure that learn's extensive research will totally debunk everything you think to be true! Great advances in cycling/tug-o-war technology and sports science like this don't come along every day, you know. It'll be traumatic at first, realising that you've been wrong for so long with all that lab work, but I'm sure it'll be worth it when you experience the speed of "simultaneous release of instant maximal torque" that this breakthrough will allow.

    So c'mon learn. Don't leave us hanging. Prove billy wrong!

    I suppose i could always change my PhD research to look at "simultaneous release of instant maximal torque" TBH, it would be a first in the field and probably get me a very good job as a hydromechanics Prof.


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    #27
    tunney
    Registered Users Posts: 12,583 ✭✭✭✭tunney


    Well I for one am convinced.
    I'm going to bite the bullet and order some PowerCranks in the morning.


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    #28
    Lumen
    Registered Users Posts: 31,031 ✭✭✭✭Lumen


    Does anyone have a graph of efficiency against cadence, where efficiency would be formulated as W/VO2 ?

    I would have thought it pretty easy to measure the power and oxygen use at different cadences, with the right equipment.

    I've read various things like:

    - Low cadence recruits more fast-twitch muscle fibres which burn glygogen (presumably indirectly) at a faster rate
    - High cadence is less "tiring" but also less "efficient". Is this "tiring" due to muscle glycogen depletion of neuromuscular effects?
    - Muscle glycogen is local, liver glycogen can be utilised more widely (not sure how this works, or what the effect is on time to exhaustion)

    ..but haven't seen any of this quantified in a way that is actually useful.


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    #29
    Jawgap
    Closed Accounts Posts: 20,297 ✭✭✭✭Jawgap


    Something like this.....?

    http://www2.bsn.com/cycling/articles/cadence.html

    fig1.gif


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    #30
    '68 Fastback
    Registered Users Posts: 389 ✭✭'68 Fastback


    Can anyone tell me if the angle of the dangle has any adverse effects on the simultaneous release of my instant maximal torque?


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    #31
    tunney
    Registered Users Posts: 12,583 ✭✭✭✭tunney


    Lumen wrote: »
    Does anyone have a graph of efficiency against cadence, where efficiency would be formulated as W/VO2 ?

    I would have thought it pretty easy to measure the power and oxygen use at different cadences, with the right equipment.

    I've read various things like:

    - Low cadence recruits more fast-twitch muscle fibres which burn glygogen (presumably indirectly) at a faster rate
    - High cadence is less "tiring" but also less "efficient". Is this "tiring" due to muscle glycogen depletion of neuromuscular effects?
    - Muscle glycogen is local, liver glycogen can be utilised more widely (not sure how this works, or what the effect is on time to exhaustion)

    ..but haven't seen any of this quantified in a way that is actually useful.

    But then again the elite IM crowd recomend low cadence and thats going to have to be efficient.


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