If placebo didn't work, they wouldn't have to control for it in studies, right? :-)

It's funny...the guy who I'm borrowing the Osymetric ring from told me straight out that he doesn't care if it inflates the power on his Quarq and/or if it actually helps his power...he's sticking with them just because he likes how they feel.

I only notice a real difference in feel when climbing out of the saddle. Other than that it feels quite normal. Except for muscle use which I noticably used my hamstrings and glutes more. For now I'm sticking with them because my Rival rings suck (don't shift) and I paid money for these :P. When I do purchase my Quarq (which this molasses rate of saving will be around January) I may have to re-evaluate or I can just remember to take 4% off my power numbers when comparing to others or I could intimidate the competition.

Or, just buy a powertap...

Tom if you plan to use them for TT's and round rings for the road bike won't you constantly be working against the muscular adaptation developed on the Osymetric rings? It took me a couple of weeks to feel completely comfortable "adapted" to the Osymetric rings on my TT bike. Consequently I switched to Osymetric rings on the road bike as well to keep from "readapting" to round rings.

In a word...no. I actually found when riding the Osymetric big ring combined with a round small ring that it only took a minute or two of riding to "get used" to the different feel when going from one ring to the other...the funny thing being that it didn't matter if I was going round -> non-round, or non-round -> to round, after the transition my pedaling felt "jerky". That shows me that (at least for me) any "adaptation" occurs fairly quickly.

BTW, after talking a bit about this subject with a guy much smarter than me (Hi Jim!) there's something about that "adaptation" thing which would tend to imply that non-round rings won't really "work". Here's why: the use of non-round rings is built on the assumption that one can change the joint angle velocities (and thus muscle shortening speeds) in the upper portions of the leg (i.e. the hip and knee joints) as compared to when the legs are attached to a crank with round rings. The "problem" is though, that there are redundant degrees of freedom in the leg structure (i.e. the ankle joint..and even foot flexure) that may prevent this. Here's the kicker though...one can potentially vary those joint angle velocities around the pedal stroke by a much greater margin than any non-round ring could accomplish, just by changing ankle flexure.

The body is an amazing thing...and typically "left to it's own devices" will find the preferred joint angular velocities and muscle shortening speeds. So, what may actually be happening during those "adaptation" phases is your body re-learning how to pedal so that your preferred joint velocities are accomplished. Make sense? This is most likely the reason why, despite some analytical findings to the contrary, little to no power change between round and non-round rings is found through the vast majority of the scientific literature.

So...to get back to your question...I'm not that worried about having different rings on the road bike and TT bike, since my only reason for thinking they may "feel" better for me on the TT bike is probably more of a fit question, and something that I may be able to accomplish anyway with some shorter cranks I have coming my soon ;-)

Tom

Could you speculate why the quark values are inflated?

What do you think is going on?

My understanding is that power is power, wondering your thoughts, why do you think the values split?

So is the jury still out for you whether you plan to use the rings? Have you come to a definitive conclusion?

Well...let's just say that knowing what I know now, I'm not expecting any magical power increases from them ;-)

And, if I can get the same "feel" I'm looking for on a TT bike with a shorter crank arm, I know which way I'll be going (and it most likely won't involve buying over-priced chainrings)...

The body is an amazing thing...and typically "left to it's own devices" will find the preferred joint angular velocities and muscle shortening speeds. So, what may actually be happening during those "adaptation" phases is your body re-learning how to pedal so that your preferred joint velocities are accomplished. Make sense? This is most likely the reason why, despite some analytical findings to the contrary, little to no power change between round and non-round rings is found through the vast majority of the scientific literature.

Ahh... so there is something you like about the "feel" of the chainrings? ;)

Another observation. My cadence is much lower with these chainrings, when I'm really mashing a big gear it feels smooth and doesn't feel like I'm going to rip off my knees like it normally does. I usually run a pretty high cadence averaging about 90-95 rpms with a mode of 99. On today's 4.5 hour ride I averaged 84 with a mode of 87. Unless I am mistaken... this could be an advantage as slower cadence utilize more slow twitch fibers which would mean that I'm not fatiguing as much over the course of the ride at a naturally selected cadence.

When I'm back at a computer I will look up the studies I had seen which led me to believe otherwise because what you stated was my understanding for a long time as well.

Doval chainrings are cheaper than a new crank set. Or most other chainrings that actually shift for that matter

Understood on the power #'s issues.

Coming back with studies about Cadence, basically since cycling isn't force limited slow twitch fibers are plenty strong. But they also have longer contraction times and are therefore more efficient at low cadences, whereas the fast twitch fire quickly so prefer a higher cadence. http://www.umass.edu/locomotion/pdfs/job-2006.pdf http://www.edb.utexas.edu/...)%20152-157,1994.pdf

I know one of the claims Rotor and Osymmetric has made is longer endurance and a slower increase in lactic acid. My observations here could show why that might be, if it is at all. I haven't seen any studies actually look at this effect they have all looked at the power numbers.

Tom A. wrote:

Basically, if that is true, then going to non-round rings is self-defeating. It's amazing how our bodies can figure out the "best way" when left to their own devices ;-) Or, to quote Jim Martin "All the theory and modeling in the world will not suppress the way people actually pedal." ;-)

Those were the studies that were shown to me and I didn't have enough knowledge to say that my understanding was right and the studies weren't.

The knee and ankle angles stuff makes sense to me, and I wouldn't call it self defeating. It still intimidates, every group ride I've been on since I've got them despite not being any faster: "Man those oval rings really make a difference don't they? You're really cooking it today." If the competition thinks you are faster then they definitely won't be able to keep up, it's all mental!

Tom A. wrote:

I found this on the subject at hand today which appears to confirm that non-round rings don't change the activation of the "driving" muscles:

Adaptation of muscle coordination to altered task
mechanics during steady-state cycling
http://www.me.utexas.edu/...Papers/job33(2b).pdf

"It is also interesting to note that all the muscle
coordination adaptation occurred in the transition
muscles, and not the power muscles. These results suggest
that the transition muscles play an important role in
adapting to changing pedaling conditions and "fine-tuning
muscle coordination while the functional role of the
power producing muscles is more elementary and governed
by the task mechanics."


I also found it interesting they observed that the adaptation, even with a fairly large ovality ring, occurred quickly (within 10-20 pedal strokes), which matches what I've felt when riding around and switching back and forth between a round and non-round ring.

I'm gradually coming to the conclusion that a better name for these things would be "Placebo Rings"... :-/

If there are power measurement issues regarding quark etc due to infered as opposed to direct measurement then I would say that you have to look for the best measurement which in this case should be tested as far away from the crank as possible.

Ideally in an erg setting measuring both mechanical out put and metabolic power.

The issue with the Quarq along with the SRM is that they both use a power calculation algorithm that assumes constant angular velocity throughout a pedal stroke, which the non-round rings change. Basically, the torque is being multiplied against a rotational velocity (the average) that is higher than the actual crank velocity while the torque is being applied. Thus, they over-read.



Been there...done that, both indoors as compared to a LeMond PowerPilot and out of doors in comparison to a PT. The inflation is real.
http://forum.slowtwitch.com/...ic%20lemond;#4201113

Not discounting what you did in erg mode, my point is that analysis of inputs i.e: metabolic power formation (ie: RER, VE, HR FE02 etc..)

is critical to analyzing the benefit of these rings vs standard, I am still on the fence regarding these rings my only opinion is that as a natural "masher" and out of the saddle climber I like 'em!

Will likely do my own analysis to back up my feeling.

One thing I would find interesting is if anyone actually has any data as to how much pedal speed varies throughout the pedal stroke, re round vs non round?

Data in M/S at angles?

Any data? I am interested because not only is this important to our discussion, but is important to other topics re cadence/force/crank length etc.

http://forum.slowtwitch.com/...rch_string=;#4274299