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

learn

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

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.

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.

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.

Beasty

tunney wrote: »

FFS is this Frank from powercranks?

Last time you asked him, he said no

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

Lumen

tunney wrote: »

I've worked alot on my pedal stroke

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

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.

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.

Lumen

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

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.......

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.

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

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

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).

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........:)

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?

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

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).

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:)

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.

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.

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.

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:

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!

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.

tunney

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

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.

Jawgap

Something like this.....?

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

'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?

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.

Jawgap

There's also this - Determinants of “optimal” cadence during cycling

Sorry it's only the abstract, but as the full article is subject to subscriptions restrictions it can't be posted in a public forum.

I don't think they'd mind a few of their graphs going up though

Lumen

tunney wrote: »

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

What's their definition of "low"?

The last graph that Jawgap posted shows that for lower power outputs (relative to LT, presumably) the "optimum" cadence from an energetic cost perspective is lower.

Presumably IM cycling done at a lower power output than most cycle racing since the event duration is so long.

I feel the shadow of "Lance pedals at high cadence so it must be good" during these discussions. I would be interested to understand more about how grand tour riders balance energy depletion against muscular stress. Some of Nic Roche's reports from the last TdF presented a pretty casual attitude to eating on the bike, which seems at odds with the "gel every 20 minutes" type discipline of the IMers.

tunney

Lumen wrote: »

Some of Nic Roche's reports from the last TdF presented a pretty casual attitude to eating on the bike, which seems at odds with the "gel every 20 minutes" type discipline of the IMers.

When they finish the stage what do they do?

The fuelling concerns is not the bike but when you get 2 hours into the run.

billy.fish

PLease lads dont consider cycling and triathlon in the same light.

Training different, needs different, its all different. You cannot compare economy and efficiency data from the two.

Also, go make sure you all know how economy and efficiency are different before i start ranting again.

Lumen

billy.fish wrote: »

Also, go make sure you all know how economy and efficiency are different before i start ranting again.

Maybe you should tell us instead of ranting ? :pac:

billy.fish

Lumen wrote: »

Maybe you should tell us instead of ranting ? :pac:

Never! That would require thinking.I'm officially on holiday now and off to ride my cross bike in the snow

tunney

billy.fish wrote: »

PLease lads dont consider cycling and triathlon in the same light.

Training different, needs different, its all different. You cannot compare economy and efficiency data from the two.

Also, go make sure you all know how economy and efficiency are different before i start ranting again.

bites tongue, its christmas, must not wind billy up, its too easy.

ROK ON

Who would have thought that a cycling discussion could be so interesting.
Well done for enlightening me.
It seems I have a lot to learn.

leftism

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. 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.

My EMG recorder will measure whats going on in your muscles at about 2000Hz so if you want to come in and demonstrate your technique i'd be happy to test you. If you can recruit sufficient muscle fibres at 12 o'clock to generate any significant torque i would be well impressed. As for what you are proposing, i would have to agree with Tunney that you cannot exert a higher torque at 12 o'clock relative to 3 o'clock. While i'm not researching this area in particular, i have seen enough EMG data at various cadences to verify that virtually all the major force producing muscles in the leg are switched off as the pedal passes over top dead centre. Rectus Femoris is the only muscle in the knee extensors even remotely capable of being active at this point, because it is the only bi-articulate muscle in the quadriceps. I've seen some of the more elite cyclists and triathletes capable of utilizing their Rec Fem to generate "some" extra power here, but nowhere near the forces necessary to exceed force generation at 3 o'clock....

I've read some papers published in Asker Jugendrup's book "High Performance Cycling" which outlined how they successfully trained elite cyclists to optimise torque production throughout the crank cycle but the overall result was a reduction in power outputs at threshold and above due to fatigue. Recovery during each pedal cycle and utilizing the moment of inertia is as important as force generation.

tunney

Maybe someone painted the numbers on his clock wrong?

billy.fish

tunney wrote: »

Maybe someone painted the numbers on his clock wrong?

Possibly a digital clock so would not infer position.

leftism

billy.fish wrote: »

Possibly a digital clock so would not infer position.

Damn digital clocks!!!

Are we sure he didn't mix up 12 o'clock and 6 o'clock? It'd make more sense than what he's talking about, even though its still a bit far fetched...

Totally agree with you about people misinterpretting physical mechanics of pedalling to the actual biomechanical processed going on in a human being. Just because our joints go through a set range of angles, doesn't mean they will work the same way throughout that range... Wish they did though! hahaha

billy.fish

leftism wrote: »

..I've read some papers published in Asker Jugendrup's book "High Performance Cycling" ...

Good book, nice summaries or some very key papers in there, not his work mostly but others in his area. Asker has pretty much moved full time into the substrate utilisation area. Real interesting area spending way to much time reading about it the last few years to hell some folks out....Tunney

if you've not picked up 'High Tech Cycling' by Ed Burke its worth the money. Also dig out 'The Science of cycling:Part1/2' if you are looking for a 2 good overview journals. Think its Padilla not sure. Have the .pdf's here if you don't have it.

leftism

billy.fish wrote: »

Good book, nice summaries or some very key papers in there, not his work mostly but others in his area. Asker has pretty much moved full time into the substrate utilisation area. Real interesting area spending way to much time reading about it the last few years to hell some folks out....Tunney

if you've not picked up 'High Tech Cycling' by Ed Burke its worth the money. Also dig out 'The Science of cycling:Part1/2' if you are looking for a 2 good overview journals. Think its Padilla not sure. Have the .pdf's here if you don't have it.

I've read some chapters in Ed Burke's book, v.good book. Haven't read the Science of Cycling though. What do you make of Askers work with carbohydrate mouth rinsing???? Seems a bit far fetched to me.... I've heard him talk a couple of times and while his research is quite convincing, i think he lets himself down by making a HUGE leap when suggesting the existance of some sort of CHO receptors in the tongue. CHO mouth rinsing increased endurance therefore, there is a magical 6th sensory organ located in the mouth which is yet undiscovered... We could call it the Askereceptor :rolleyes:

billy.fish

leftism wrote: »

Askereceptor

Say that out loud 10 times and you can metabolise 2.3g of CHO/min

Yeah his work is good, very good, and his data is clean...very clean....if you have done any research this sets off bells.

I agree with some of his ideas, infact many of them, but he does tend to say '...blah blah blah does this...and so we can cure cancer' sometimes.

BUT

Look at the time frame he is suggesting the rinsing for, its events less than 45mins so TBH you are going to be ideally fully fuelled, cells saturated (hypersaturated if you believe some other papers) from pre-feeding. So even if its only a placebo effect it not going to be an issue of not enough fuel being capable of being delivered for that period.

Interesting area, but if you take the research literally you only need to rinse with a CHO source; ie sugar and water, to get the effect that its describing. I find it relieving for his other research that Asker is publishing this data as allot of his work is funded by Powerbar -aka Nestle.

One does not publish data that destroys ones own funding....often

leftism

billy.fish wrote: »

Say that out loud 10 times and you can metabolise 2.3g of CHO/min

Yeah his work is good, very good, and his data is clean...very clean....if you have done any research this sets off bells.


Interesting area, but if you take the research literally you only need to rinse with a CHO source; ie sugar and water, to get the effect that its describing. I find it relieving for his other research that Asker is publishing this data as allot of his work is funded by Powerbar -aka Nestle.

One does not publish data that destroys ones own funding....often

First rule i was taught when reading a journal: turn to the back page, find out who is funding the work. Then read the paper.

Sure look at the Lucozade commercials: "Makes top athaletes go 33% longer." That result is highly misleading since the protocol involved a 2hr glycogen depleting exercise phase, followed by a series of 1 min sprints. Subjects went 2 mins longer in the sprints on the lucozade arm of the trial. In reality that means they went 126 mins as opposed to 124 which when you include group variability is well outside statistical significance! But adjusting statistics and ignoring the 2 hour glycogen depletion phase and hey presto, top athaletes go 33% longer. All funded by Glaxo Smyth Klein...

tunney

I think we should get one of this for billy, they do great science.

billy.fish

tunney wrote: »

I think we should get one of this for billy, they do great science.

*twitch*

No comment for reasons of professionalism.

adrianshanahan

billy.fish is fantastic!

That is all

dave2pvd

Some good science there, Mr. Learn.

I like me some good science, I do:

https://www.youtube.com/watch?v=RXJKdh1KZ0w