Curious writes: “Don’t know that anyone would argue that you should “apply” backpressure on the upstroke.”
Winkle does, or, he, at least, argues there is no benefit to trying to reduce or remove the backpressure on the upstroke. Push harder is the Winkle mantra.
What Winkle actually did write:
“Try thinking of it this way: one way or another, the upstroke leg has to get from the bottom of the pedal stroke to the top of the pedal stroke. That involves both lifting it against gravity - thus increasing its potential energy - and accelerating/changing the direction of the different limb segments - thus increasing their kinetic energy. The energy used to accomplish these tasks can come from either 1) contraction of muscles within the upstroke leg or 2) from the rising pedal. If the former isn’t large enough - in other words, if you don’t pull up and forward fast and hard enough to fully “unweight” your leg - there will be some “back pressure” on the pedal. Just because there is a countertorque, however, does not mean that energy is being wasted - it is merely means that the pedal is rising more rapidly than you can get your foot out of the way.” (Post #13)
and
“The reason that people get so wound up about backpressure is that they assume that it is the result of active muscle contractions, and therefore does indeed represent a waste of energy. One of the major points of the Kautz and Neptune paper is that this assumption isn’t necessarily correct.” (Post #15)
Granted, I don’t have the scientific background to truly understand these things, but my interpretation of the above statements indicates that he would agree with me.
How did the Mensa meeting go? I used to be invited to them all the time…to park cars
Here’s the thing that bothers me about all of this counter-torque, negative work, potential energy/kinetic energy, wasted energy stuff…Muscles and bones aren’t the same as machines in the way the ideas behind these terminologies are applied. There are often counterintuitive things occuring, just as the recent paper cited states.
While I agree that it MAY be more inefficient (requires more energy) to raise the leg internally (with hip flexors, better timing of the hamstrings, etc.) than to push it up with the opposite leg’s extensors; more efficient doesn’t automatically mean more economical in terms of a specified level of power at the rear wheel over a specified period of time.
It may be that different power levels are more economically maintained using different pedalling techniques…such that maximum power over a short time span may require a “masher’s” pedal stroke to be most economical, RAAM power may also best use a “masher’s” style, and in between may be better served to use the less efficient circular pedalling style, as long as the event is done at an effort level that is sub-lactate threshold. OR, switch all of this around, or whatever other scenarios you can come up with. The point is, nobody has really done the science to compare all of these different pedalling styles to one another, in different conditions, at least, not when the cyclists have had a chance to train in these different styles.
Maybe we’ll see these studies done in the future, it’s impossible to have done them before, PowerCranks are, relatively-speaking, a brand new thing, so are Rotor Cranks.
That is not the only posting on this topic. Be that as it may, according to those statements it makes not a whit of difference of the amount of back pressure on the upstroke (as long as there is no active muscular resististance) as long as the total energy expenditure was the same. So, there would be no difference between someone fully unweighting and someone being totally passive, as long as the total energy expenditure was the same. Pushing harder easily makes up for not pulling harder. He justifies this by claiming performance is cardiac limited. Without this cardiac limitation “requirement” (and the need for the muscles to fatique the same regardless of the forces generated) his assumption is blatently preposterous.
I await the reference that demonstrates this to be true. Certainly he would be hard pressed to find a single top pro fench cyclist who was totally passive on the upstroke.
