Max power? Or threshold (FTP) power? I'm sure everybody looks ugly when laying down their max power, but since you can only hold that for 1-10 seconds the aero implications are probably minimal.

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Citizen of the world, former drunkard. Resident Traumatic Brain Injury advocate.

Ok not max sprinting power but like max 1-2 min chase power efforts. I’ve been told you can tell when I’m giving it all but my body bobbing up and down vertically

Is it your seat is too high and your hips rock back n forth?

Or is it the front of your body bobbing up and down?

Why are you even worried about aerodynamics when putting out excessively high power for a short duration? Is this on a road bike and what kind of racing are you doing? Once you cross a certain output most people will tend to lose form to some extent.

Because I want max speed , not max power. If I can put out less power and hold form which gives less drag and in turn more speed that would be a benefit, even for 1 min.

My thought was bobbing, I think mostly due to my arms flexing at the elbow, my front end would cause a significant increase in drag. Was looking for some studies that would quantify that.

The question should probably be understanding how your position changes. I am guessing you elbows stick out or your chest and head raise up. There isn't going to be a general rule because everyone's positional changes would different.

The closest I have seen is some windtunnel work by Slipstream years ago. Julien Dean did some testing to look at how aerodynamic his position in the lead out was. When he would stick his elbows out at the end of the lead out they estimated it was costing him 100 watts. Also consider Cavrndish puts out 500 watts less the Griepel or Kittel. Ya there is a size difference, but Cav's big advantage has always been how low he gets in the sprint for aerodynamics

I don't think I've ever seen any data on this made public, although it's certainly been looked at (Hoy did testing on stuff like this before London)

My suspicion is you might find a top level kilo rider or team pursuit squad that has this kind of info.

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My Blog - http://leegoocrap.blogspot.com

I suspect it will depend on exactly how much you "bob." It should be possible to do a field test to see whether there's a change in CdA at higher power output (compared to the base assumption that your CdA is constant across the entire spectrum of power).

I would hypothesize that your CdA would be the weighted (for time) average of the CdA for each position you adopt.

IOW, I don't the bobbing, per se, would measurably impact your aerodynamics.

I assume the frequency matches my cadence, the amplitude must be pretty high for people to notice, so I think it must be pretty pronounced. People can tell when I’m going all in on a case versus not.

Would the Platypus tech be able to find this ? I suspect yes.

Side question is what effect would this have to the ride in my draft ? Could they feel an oscillation of in/out of draft ? Almost similar to peaking out from behind a rider in front to the side ? More factors I’m sure based on size of two riders. I visualized air flowing over my back going up and down creating a more turbulent air flow than if I’m locked still which I assume creates a more laminar flow over my back and theirs. I’m creating a turbulent flow for everyone, which could be good or bad depending on the race situation.

If the amplitude of your bob were large enough? I suspect yes, too. But the only thing to do if you really want to know for sure is to test.