I'm thinking you might want to resolve this down to pedal force...

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I’m always DFMD (Down For More Data) At some point it becomes a request for all the things lol.

I said torque because I view it as a field on my cycling computer and find it more consistent than cadence or power.

I was trying to avoid people posting their preferred cadence, but two of three (power, torque cadence) is enough to guess the other.

If you have crank length, then dividing torque by ((crank length)*1m/(1000mm)) will give is pedal force in Newtons.

I’ve always been curious about how pedaling forces affect bike fit. One can TT with a neutral core and resting on arm pads, to almost no weight on arm pads with tension through core muscles, or set up to be pulling on aerobars with deliberate core engagement for shorter efforts. I think these “dynamics” are much more important than the traditionally discussed “geometric” fit variables, but I think they relate more to W/kg and goals in a manner that we don’t seem to have the data to discuss or elaborate on.

Right...but the way I look at it, your body doesn't perceive "torque", it perceives the FORCE you're putting into the pedal...which is why I find "quadrant analysis" and looking at AEPF/AEPV (Average Effective Pedal Force/Average Effective Pedal Velocity) as being more insightful than torque or cadence. So, if you're asking for torque, you really need to know crank length to be able to put it into context.

Plus, it's an easy to access chart in GoldenCheetah ;-)

For an example of of how it can be used to compare efforts and setups: http://bikeblather.blogspot.com/...erwithin-reason.html (edit: and note that the reported torques would be vastly different for those 2 setups)

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In terms of fit, both force and torque together would affect one’s fore-aft CoM preference. The average pedal force location and direction would be cool to see, but that’s a big ask for a public forum haha.

I also think that there is something inherently important about average torque that it would be the best starting point for discussion, aside from being easier to calculate.

Nope...you're still talking about the effects of force, not torque.

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I agree with Tom when it comes to perception as well as bike fit force is more important. Also it is reasonable to acknowledge that force on the pedals changes the downward force of body weight on the contact points. The most significant of these is the saddle for most riders but of course your center of mass does help with taking this into account since the more forward the more weight or down force on the forward items bars, pads etc. So as pedal force increases then the effective weight is reduced (need to accept Newton's law here). For bike fits a good exercise to tell if a person is properly balanced is to get them to pedal at their preferred power cadence etc and ask them to lift their hands from the bars without changing their body position. If they can not do this there are 2 factors, they have poor core stability and or they are leaning too far forward. GebioMized (https://gebiomized.de/en/) does this and I suspect has data to show how saddle force changes with pedal force.

So I would say the data would be more interesting when using the pedal force.

Most people don't know their pedal force or their crank torque -- but they have an idea of their cadence, power, and (sometimes) their crank length. That said, I sometimes forget that I have one bike with 170's and another with 172.5's.

Speaking of cadence and crank torque (see what I did there?) here's a plot for a hilly ride I did IRL and a "hilly ride" I did on Zwift on my rollers with a fluid resistance unit.


And a plot calculated from a contributed data file where the rider did sorta similarly "rolling" rides: the left panel shows a ride in NYC's Central Park IRL, the right panel is on the Richmond course in Zwift on a Kickr smart trainer.

...which is why I mentioned that AEPF/AEPV is easily accessed from within GoldenCheetah. Just need to load a power file and input your crank length. Voila!

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Pedal speed is a red herring.

I think you misspelled "cadence"... ;-)

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So crank torque = (crank length vector) (cross) (pedal force vector) but pedal force is applied at a location which is a function of crank length and crank angle, and it cannot be appropriately translated to a single vector at the crank center without an accompanying moment, hence my earlier remark.

Without such information, the force magnitude alone is too ambiguous. One could pedal perfect circles with net zero force, or only pull up and have an upward average force vector, etc.

You're overthinking it.

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I’m of the persuasion that there’s no such thing. :)

Reminds me of something I read recently:
“You ever wonder what life would be like if you weren’t always overthinking things? I think about it all the time.”

Here is my torque info... I have not measured my CoM but I think I am pretty standard for a triathlete position...

19.6/28/33.6 Nm or .273/.39/.47 Nm/kg at 71.8 kg (92 rpm preference)

I too think pedal force is more relevant. If I shorten my crank length, I'm more likely to keep my pedal force the same and increase my preferred cadence.

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Ed O'Malley
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Since we're overthinking things, shouldn't we be thinking not about average pedal force but maximal pedal force? Depending on how one pedals, max pedal force for one leg is ballpark 4x average pedal force (so if your pedaling is roughly symmetrical between right and left legs, max pedal force is roughly twice average pedal force over both legs), but I'm sure there's some variation across individuals and probably within each individual across power output. Surely when we modulate pedal force, we're modulating for the maximal force rather than the average.

I agree, and my earlier response included postulating that mean torque is probably a better proxy for peak pedal force than “mean pedal force magnitude” by similar assumptions, but I (over)thought about some more and figured i would spare that forum fight for now lol.

If people are dominantly pedal mashers, then we can assume most (85%?) of the crank torque occurs at 3 o’clock in a downward direction(ish). crank length variation is usually 170mm +/- 5mm which is less than 3% error and probably smaller in error than anything else we’re writing on this napkin.

And what about if I mr persons navel is farther north of their true center of gravity VS another persons navel being farther south of their center of mass

Can we go back to discussing what discussions BG means?

[pink] In such cases, STers should tape a string and weight from their naval, bend over 90 degrees and lean forward until the they are almost tipping over. At this instant the delta measurement between the tip of their toes and the center of the mass is the correction for their CoM measurement[\pink]

What is your mass in kg?
64kg

Where is your center of mass (call it belly button) w.r.t the bottom bracket?
??

What is your preferred pedaling torque at 0.7/1/1.2 FTP?
26/31/34

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This is a bit interesting, since proportional to your mass your numbers are 0.41/0.48/0.53. I might hazard to guess that your pedaling style had to be fairly “round” with conscious effort in maintaining pedal force throughout the revolution? I wouldn’t think one could achieve such values with a pedal-mashing style.

Some of my thinking is that people choose their gearing based on their weight and power output such that their crank torque might be proportional to body mass for a given effort.

Regarding CoM, maybe the only practical thing we can ask people is to self report how they would describe their position from max rearward saddle offset to max forward saddle offset, and how they perceive that changes for the given effort ranges.

I’d like this to be more of a discussion about how people think of power output and muscle engagement than a sterile data compilation effort, for now.

Interesting observation.
I could add, I don’t consciously select anything but do observe that cadence increases with effort.
Sub FTP hovers around 92 RPM and increases to 96-98 for VO2 max efforts.

L/R balance is always pretty much exactly 50% R, 50% L.

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