Slowman wrote:
Tom A. wrote:
Slowman wrote:
stevej wrote:
Why would you be interested in torque and not force? Torque isn’t measured. It’s calculated. Force is what’s measured by the strain gauges.two things. first, i predict that by the time we hit 100 posts no one arguing his thesis is going to remember the point of the exercise. so, for the purposes of the point of the exercise, i don't think it makes any difference. if i choose torque as the metric, and i get a wild hair and decide to move up or down 5mm in crankarm length, which i'm unlikely to do, this means a 3 percent difference. so, for the purposes of the exercise, i'd be cool with either. i would not find it a liability to get one metric over the other. right now i have neither.
second, it's much easier to get torque. if i have power and cadence i have torque. as tom pointed out, it's also pretty easy to get force, but i doubt it's easy to get force around the pedal circle without some significant calculations no device maker's likely to do. so, if we're going to circle jerk this thing and then go back to the NCAA tourney and forget about it, fine, let's debate. but a device (or app) maker could give us torque around the pedal circle by coffee break tomorrow if he wanted. meaning, if this were something worthy of pursuit.
Same is true for force (tangential effective pedal force)...they'd just need the user to enter crank length (to divide the torque by).
In fact, I plotted those QA plots I referred to above (which you still haven't told me what your take-away on them is yet...but, I digress...) using power meter data in GoldenCheetah. The only additional information needed was crank length. WKO has the same function as well.
Let me ask this...are you somewhat fixated on torque because you think you might be able to do something about it based on measurements within a pedal stroke cycle? For many reasons (I'm sure you've heard), that's not really "worthy of pursuit"...
first, i'm not fixated on torque. i'm asking whether riding by a different metric - and either force or torque would work for me - is a worthwhile exercise in training. is it worth pursuing? i promise you i'm much more fixated on how nevada does against sister jean this afternoon.
rchung, if i understand him correctly, thinks within the pedal circle is important. i don't know that it is. i agree with you that peak force is pretty easily calculable. it just requires and extra field in the equation. others tho, in this thread are arguing that it's silly to back calculate since force is a direct measure. which it is. just, fat chance you'll get that number any time soon from anybody. tho i'd be happy to be proved wrong.
bear in mind, you don't need to be a device maker to give us either. or any. you can be an app. zwift could do this. trainerroad, GC, fulgaz.
The only times I've ever been interested in pedal force (or torque) is when looking to see if I'm gearing limited in climbing. Long ago I noticed that if I'm over-geared for a particular climb steepness, then my power drops. Looking at the crank torque plot in the old PT software (this type of information HAS been available for quite some time) showed me that the crank torque (i.e. pedal force) stayed constant and I just dropped cadence...hence the power dropped. In other words, at that effort I was force limited. That told me for that climb I didn't have low enough gears.
Other than that...and I think this may be a big part of what RChung has been trying to display...crank torque, pedal force, cadence ALL vary by quite a bit during riding, so trying to artificially constrain one of those things over the others isn't very fruitful. Your body is basically going to "do what it does" to accomplish the effort. Our brains do a pretty good job of controlling our muscle activation for the given effort level.
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