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Faster is faster...
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TOPIC: Faster is faster...

Faster is faster... 12 years, 5 months ago #2074

  • Tom_Anhalt
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Kraig,
A couple of quick questions about your latest article:

1. What do you mean by the knee to spindle relationship not being preserved when rotating the position about the bottom bracket? Are you referring to KOPS (Knee Over Pedal Spindle)?

2. You state near the end that your power "in the drops" is equivalent to your power "on the hoods", yet obviously the hip angle is tighter. How far forward and up would you need to move the saddle if you used your "in the drops" position as the starting point of the rotation? In other words, use the "in the drops" hip angle as the position you want to maintain.

3. Where are the red shoes?

Re: Faster is faster... 12 years, 5 months ago #2077

  • Ashburn
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Couple observations (in re Tom's post above)

I have the same question -- what does it matter that the knee to spindle relationship had a direction vector change? The muscles don't know about gravity -- they just fire. So long as they fire over the same range of motion, it really doesn't matter if we're on a bike or hanging upside down.

Second -- I actually did the position change Tom asks about, but working backwards. I took my (forward & low) TT bike position and applied it to my road bike recently. I took various measurements, and made a big triangle out of three yardsticks to compare between bikes (a cabinet-maker would call that tool a "story pole"). I marked pedal-spindle to hip joint bone (whatever it's called) to outside end of collarbone, and back to bb, as a triangle. I preserved that triangle exactly.

What I ended up with is the road bike saddle tip 5.5 cm behind the bb. The tri bike is set up 3 cm in front. The armpad drop on the roadie is about 8cm, and on the tribike it is ~20cm. My body position on the road bike riding in the clip-on bars is identical to riding in the drops. I.e., I can move between the clip-ons and the drops with no change in shoulder height.

So, I have shown that somebody built like me (6' with avg proportions) can preserve joint angles between the two bikes well within normal fit and setup parameters. Next, I'm going to go out and do some trials to see if there is a material CdA difference (requiring that I ignore any frame-induced CdA differences. My TT frame has deep-ish downtube, but is otherwise not very "aero". Road bike is round-tubed.)

I'll post some pics in the next couple of days so that folks can enter their guesses about the outcome. What I think you'll see is that the TT position "looks" aero, and the road bike position "looks" like a parachute.

As Kraig would say, we'll let the data do the talking. I would love to find out that the road bike position is equally aero -- it is more comfortable to ride like that (less weight on the arms and no sore neck from peeking up the road).

Re: Faster is faster... 12 years, 5 months ago #2078

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[/quote]I have the same question -- what does it matter that the knee to spindle relationship had a direction vector change? The muscles don't know about gravity -- they just fire. So long as they fire over the same range of motion, it really doesn't matter if we're on a bike or hanging upside down.


I agree fully, but when moving too far forward, the frontal area of the legs starts to become a factor.
After having read a vast amount of material on this page, with Kirk's quote being the most important:
If you look at the "0.183" thread, moving my saddle forward will result in:

1) Increase the frontal exposure of my leg from hip to foot since that angle will move to 90 degrees.
2) Increase the amount my toes point towards the ground, increasing frontal exposure for the foot.
3) Raise the highest part of my back relative to the ground and the bottom of the crank circle...in accordance with the raising of the saddle as it is moved forward to preserve extension
4) Change the articulation of all biomechanical interactions with the bike relative to gravity.

I have gathered that moving too far forward will defeat the gains of being able to drop the front end due to the increase in leg frontal area. The challenge of getting into a truely aero position is definately a catch 22. The true aero position almost assuredly has to have as tight of a hip angle as the rider can handle. I have messed around with literally thousands of different TT positions (with 3 different frames, about 10 seat posts, 5 seats, 1 ergo stem (key part) and 6 different bar/aerobar setups) and have found over and over that a position with a hip angle tighter than what I would ever use on my road bike just does not work and would take too much training in the TT position to realistically utilize. After reading all of Kirk and Kraig's info about frontal area of legs due to moving too far forward, I have definately realized that I have to make a compromise between the moving forward ideal and staying back to minimize leg frontal area, while at the same time keeping a hip angle that is in the range of normal road bike usage. Trying to keep all of various options in mind can create an unending game of trial and error to find the perfect position.
hope this helps-
Matt W.

quotes 12 years, 5 months ago #2079

  • mcw2109
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oops... those quotes are bass ackwards

Re: Faster is faster... 12 years, 5 months ago #2080

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Tom_Anhalt wrote:

1. What do you mean by the knee to spindle relationship not being preserved when rotating the position about the bottom bracket? Are you referring to KOPS (Knee Over Pedal Spindle)?


I don't think I was being that specific. Just that the effective leg force vector is different when you dork with the saddle.

2. You state near the end that your power "in the drops" is equivalent to your power "on the hoods", yet obviously the hip angle is tighter. How far forward and up would you need to move the saddle if you used your "in the drops" position as the starting point of the rotation? In other words, use the "in the drops" hip angle as the position you want to maintain.


I am as low, or lower in my drops position than I am in the "virtual" rotated position.

Drops position is the yellow trace in the image below:



3. Where are the red shoes?


They're on my feet - don't forget I have an exclusive sponsorship deal with those guys!
-kraig

Re: Faster is faster... 12 years, 5 months ago #2081

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Ashburn wrote:

I have the same question -- what does it matter that the knee to spindle relationship had a direction vector change?


I would hypothesize that the pedal force timing/muscle recruitment is different when the saddle position is moved forward 25.5cm. Is one better than the other? Well, I just ask my buddy SRM what he thinks...

Second -- I actually did the position change Tom asks about, but working backwards. I took my (forward & low) TT bike position and applied it to my road bike recently. I took various measurements, and made a big triangle out of three yardsticks to compare between bikes (a cabinet-maker would call that tool a "story pole"). I marked pedal-spindle to hip joint bone (whatever it's called) to outside end of collarbone, and back to bb, as a triangle. I preserved that triangle exactly.


Why preserve the magic triangle? I'd like to see how far you can bend over (BTW, the alternate/original title to "Faster is Faster" was "Sooner or Later you're gonna have to bend over...")
-kraig

Re: Faster is faster... 12 years, 5 months ago #2082

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Why preserve the magic triangle?
There's nothing magic about it. It's just how I have adjusted over the years. Any tighter and my power starts to fade. It's about as far as I can bend over. A line running from the pedal spindle to my hip and out the top of my collarbone is ~90 degrees. Again, nothing magic about that angle, but it is as tight as I can go. So I set up the road bike the same way.

I'm not trying to determine the optimum torso-legs angle, just take what I've been doing and rotate it back and see what happens to CdA and comfort. I have no intention of bending over more than I already do.

Bending Over? 12 years, 5 months ago #2083

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Ashburn wrote:
I have no intention of bending over more than I already do.


Rick,

It's been awhile since my geometry class back in the day(so maybe I did something wrong...), but here is how I determine the moving the saddle forward and up relationship:



my secret code: r=saddle height; deltax=distance moving the saddle forward; deltah=distance raising the saddle.

Looking at your numbers for saddle/pad drop for your road/TT bike, something's not jivin' if your intent was to preserve torso angle.

Again, it's entirely possible my math is wrong - maybe an independent check of my math would help the cause?
-kraig

Re: Bending Over? 12 years, 5 months ago #2084

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kraig wrote:
Ashburn wrote:
I have no intention of bending over more than I already do.


It's been awhile since my geometry class back in the day(so maybe I did something wrong...), but here is how I determine the moving the saddle forward and up relationship:


Check against my CAD estimates:

3.5/.76=4.6

25.5/4.6 = 5.5 -> I'm an engineer, so I'll call that close enough for and independent check...
-kraig

Re: Faster is faster... 12 years, 5 months ago #2085

  • Tom_Anhalt
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I would hypothesize that the pedal force timing/muscle recruitment is different when the saddle position is moved forward 25.5cm. Is one better than the other? Well, I just ask my buddy SRM what he thinks...


I'm confused here...if your position relative to the BB is truly merely rotated about the BB, why would there be a difference in pedal force timing/muscle recruitment? The only vector change (relative to the BB) would be gravity...

I'm just trying to figure out what you think would be different here...

I am as low, or lower in my drops position than I am in the "virtual" rotated position.


Are you saying you're going to just slap on some shorty clip-ons and are now a "big slam" devotee?

One additional observation...if you had been wearing a helmet in the pictures, your "in the drops" (and the "virtual rotated") position wouldn't look as good...i.e. your head would appear to be further above the highest point of your back. Therefore, starting from the "in the drops" position, you would probably want to rotate forward to get the top of the helmet even or below with your "hump"...just not as much as your original change from the "on the hoods" position. The way you presented it now, it looks like "in the drops" position (as judged by head and back profile) is as good as you can get...but it appears it could be improved on just slightly by rotating forward (or bending over more, obviously) when you take the additional height of the helmet into consideration.

Re: Faster is faster... 12 years, 5 months ago #2086

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Tom_Anhalt wrote:

I'm confused here...if your position relative to the BB is truly merely rotated about the BB, why would there be a difference in pedal force timing/muscle recruitment? The only vector change (relative to the BB) would be gravity...


I dunno for sure, but here is how this caveman is thinking... (yeah, I'm giving anybody who is reading free reign to lay down the hammer...)

Peak pedal force occurs somewhere between 9 oclock and 6 oclock (for the left leg in all the pics in the article). At this angle with the seat at a normally evolved over 100 years of bike design setback, the muscles recruited are a function of how the leg parts are positioned. In this same peak force location with the saddle 25.5 cm forward, the leg parts are oriented differently... This suggests that either the peak force is at a different position in the pedal cycle in order to recruit the same muscles (what happens to the net pedal force vector/torque at this new position), or there are different muscles recruited in order to produce peak pedal force at the same location (say, more quad, less glut? - not a physiologist/anatomy wizard - can you tell?)...

I also think there is some boundary condition stuff going on. What are all the HPV land speed record bikes designed to -> fully prone? or laid back? I don't really know the answer to this...

Make any more sense, or am I just delusional?

I am as low, or lower in my drops position than I am in the "virtual" rotated position.


Are you saying you're going to just slap on some shorty clip-ons and are now a "big slam" devotee?


I think it all depends. Thank goodness there are tools available to let the consumer decide on their own how they'll prove what I've been saying all along: "FASTER is FASTER!"

One additional observation...if you had been wearing a helmet in the pictures, your "in the drops" (and the "virtual rotated") position wouldn't look as good...i.e. your head would appear to be further above the highest point of your back.


Well, I reckon I'd just duck my head a bit and be done with it -> no sense in over complicating things, eh?

I hope you haven't had any bad experiences, Tom, with the law of unintended consequences. I lose sleep over that law every night (thanks to a couple years with Brand S!)
-kraig

Re: Faster is faster... 12 years, 5 months ago #2087

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Peak pedal force occurs somewhere between 9 oclock and 6 oclock (for the left leg in all the pics in the article). At this angle with the seat at a normally evolved over 100 years of bike design setback, the muscles recruited are a function of how the leg parts are positioned. In this same peak force location with the saddle 25.5 cm forward, the leg parts are oriented differently... This suggests that either the peak force is at a different position in the pedal cycle in order to recruit the same muscles (what happens to the net pedal force vector/torque at this new position), or there are different muscles recruited in order to produce peak pedal force at the same location (say, more quad, less glut? - not a physiologist/anatomy wizard - can you tell?)...


Again...I'm not following...If the "system of levers" is rotated around the BB, why would the power output be changed? Wouldn't the peak force location in the pedal cycle just be rotated as well? Are you saying that your muscles "know" their position relative to gravity and fire differently because of the rotation?

Just to throw you a bone here ...have you ever read this?:
http://www.sheldonbrown.com/kops.html

There's some interesting things in here about rider CG position and forces at the rider/saddle interface that may or may not coincide with some of your hypothesis.

I hope you haven't had any bad experiences, Tom, with the law of unintended consequences. I lose sleep over that law every night (thanks to a couple years with Brand S!)


I wouldn't consider myself a good engineer if I didn't keep that in mind at all times...heck, it's something I even plan for nowadays!

Re: Faster is faster... 12 years, 5 months ago #2088

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Tom_Anhalt wrote:

Just to throw you a bone here ...have you ever read this?:
http://www.sheldonbrown.com/kops.html


Sounds like Keith and I agree, if you ask me. Go 25.5 cm forward and you are outside the range of normalcy - smaller deviations and you are fartin' in the wind. wink:

Good thing we have the tools at our disposal to truly determine whether or not FASTER is FASTER. Hey, you catchin' a theme in my position here?


I hope you haven't had any bad experiences, Tom, with the law of unintended consequences. I lose sleep over that law every night (thanks to a couple years with Brand S!)


I wouldn't consider myself a good engineer if I didn't keep that in mind at all times...heck, it's something I even plan for nowadays!


Good on ya!
-kraig

Re: Faster is faster... 12 years, 5 months ago #2090

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Looking at your numbers for saddle/pad drop for your road/TT bike, something's not jivin' if your intent was to preserve torso angle

Quite so! I was standing there in my garage scratching my head over that, too.

But what is missing in the geometry method is the fact that the saddle does not move proportionately with the hip point. On the tri bike, a vertical plane through the hip points is running a few cm behind the nose of the saddle, due to the fact of being so rotated forward and riding with weight on the perineum instead of the sitz bones.

The same plane on the road bike position is running a few cm from the back of the saddle.

The mere fact of rotating so far forward picks up a bunch of cms of apparent saddle movement. The saddle does not need to move so far as it might seem. You have also assumed that the saddle moves laterally directly under the hip point. It is actually farther down the radius, and therefore doesn't move laterally as far as the hip as the whole system rotates, even if we ignore the "sitting style" effect that I figured out.

Also -- the armpads on the road bike's short clipons are farther from my torso, and rise farther for a given rotation amount than would the tri bike clipons. A quite small effect to be sure, but just an illustration that a simple "paper rotation" does not speak to the full range of changes.

In keeping with the "Faster is Faster" theme, I did not focus on where the bike parts ended up (height, drop, seat tube angle,...). I focused on what matters -- where do I end up. I'm the same on both bikes, and the parts are where they are.

Tippin' it? 12 years, 5 months ago #2091

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Ashburn wrote:
Looking at your numbers for saddle/pad drop for your road/TT bike, something's not jivin' if your intent was to preserve torso angle

Quite so! I was standing there in my garage scratching my head over that, too.

But what is missing in the geometry method is the fact that the saddle does not move proportionately with the hip point. On the tri bike, a vertical plane through the hip points is running a few cm behind the nose of the saddle, due to the fact of being so rotated forward and riding with weight on the perineum instead of the sitz bones.

The same plane on the road bike position is running a few cm from the back of the saddle.

The mere fact of rotating so far forward picks up a bunch of cms of apparent saddle movement. The saddle does not need to move so far as it might seem. You have also assumed that the saddle moves laterally directly under the hip point. It is actually farther down the radius, and therefore doesn't move laterally as far as the hip as the whole system rotates, even if we ignore the "sitting style" effect that I figured out.

Also -- the armpads on the road bike's short clipons are farther from my torso, and rise farther for a given rotation amount than would the tri bike clipons. A quite small effect to be sure, but just an illustration that a simple "paper rotation" does not speak to the full range of changes.

In keeping with the "Faster is Faster" theme, I did not focus on where the bike parts ended up (height, drop, seat tube angle,...). I focused on what matters -- where do I end up. I'm the same on both bikes, and the parts are where they are.


Are you essentially saying that the further forward your saddle is the more apt you are to ride the tip? IOW, the center of your greater trochanter (femur hip point) moves relative to the saddle between forward and back positions?

I think that if equipment allows, paper rotations can be really close to real rotations with the difference being weight distribution and force balancing. The performance impacts of those changes will show up on a powermeter.

How does your power with an 8-10cm set-back on your TT bike (maybe applicable to your size) compare to the 3cm ahead (regardless of the very small hip angle changes)? Cheers, Kirk

Re: Faster is faster... 12 years, 5 months ago #2093

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First, an edit -- the 5.5cm setback I quoted above was from memory, and proves again why I need to write things down. I re-checked all of the measurements on both bikes this morning. All is as reported above, except that the saddle tip of the road bike is 9 cm back, not 5.5. That makes up a little of the apparent discrepancy.

Are you essentially saying that the further forward your saddle is the more apt you are to ride the tip? IOW, the center of your greater trochanter (femur hip point) moves relative to the saddle between forward and back positions?

I don't think the mere movement of the saddle forward is what causes me to ride more to the front of the saddle. It's the bending-over that does it. If you just sit right there in your chair and bend over and touch the floor, it should be apparent that your g.trochanter moves forward (and up) relative to the chair seat. The main contact point of your butt moves forward, too. The design of the saddle (and it's mate -- my butt) just sort of requires that a low torso angle means I sit on the saddle differently than in a more traditional roadie position. Perhaps the saddle "should" be farther forward under me in the TT position, but it doesn't fit in there. )

We should also keep in mind that saddle position alone does not fix the location of the g.trochanter. We slide back and forth and all around, especially in a TT setup. All we really do is get the saddle close, and then we park our butts where our bodies want it to be.

How does your power with an 8-10cm set-back on your TT bike (maybe applicable to your size) compare to the 3cm ahead (regardless of the very small hip angle changes)?

I'm not exactly sure what you are asking. For one, I couldn't set my TT saddle back that far if I tried. The saddle is pushed back almost as far as it will go right now, and it's still 3cm in front. Perhaps with a setback post I could get it a little behind the bb.

(I will also readily admit that I am not wedded to my +3cm saddle position. If I moved it back even to the bb, I think I would hardly notice the difference. The main reason it is where it is is because that's how the saddle bolts onto the seatpost I have, and I have pushed it back on the rails. A couple cm fore and aft is not as big a deal as people make it out to be, IMO. It changes balance and bike handling a bit, but not so much power production.)

But what I think (?) you are asking is whether I perceive a power difference between the road bike setup and the tri bike. With only a half dozen rides on the road bike (none of which were hard workouts) I really can't say. My impression so far is that I am materially weaker on the road bike, but I think that is simply due to the fact that I am still getting used to the change in balance. I haven't ridden the road bike in almost two years, and it still feels a little awkward when I get to lifting the power and working hard, especially on climbs. I still feel like I'm falling off the back of the bike -- this is because I spent so many hours and miles on the TT bike, falling off the front of the bike.

Are you sure KB agrees with you?.... 12 years, 5 months ago #2094

  • Tom_Anhalt
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Sounds like Keith and I agree, if you ask me.


You think? What about this quote from that article:
The most important argument I came up with to establish a basis for believeing that KOPS is only an accidental relationship, only has a weak statistical basis and is not physically siginificant is the discussion of the recumbent. In that case, the location of the rider's knees over the pedals is completely different, entirely unrelated to gravity, but the position is as effective in pedaling. This gives you a very simple way to see that the KOPS method has no basis in physics or physiology.


And this:
The KOPS rule seems sensible enough; it puts the knee in line with the pedal at maximum pedaling force, which must help, right? Wrong. The KOPS rule of thumb has no biomechanical basis at all. It is, at best, a coincidental relationship that puts the rider somewhere near his or her correct position....The reason the KOPS method is arbitrary is because it relies on the gravitational orientation of a plumb bob. The direction of gravitational force has no bearing on the rider's ability to pedal, except for providing a constraining force at the saddle to counteract the peak portion of the pedal cycle. In analyzing the pedaling motion of a cyclist, it is not useful to think of the thigh as pushing down on the pedal through the knee. It is better to look at the rider's leg and its attachment to the pedal and crank as a system of levers and pivots, and to consider how the pedaling forces and joint torques act on this system.


Along with this:
The knee joint works exactly the same and has the same forces acting through it regardless of its orientation. As an example, note that a recumbent rider's position does not in any wy relate to the force of gravity acting through the knee. The recumbent rider's legs act in the same mechanical way on the crank, even though he is rotated roughly 90 degrees from the standard position. the gravitational constraint that is lost at the saddle is replaced with a mechanical one, a seat with a backrest.


Do you see now why I'm having a hard time seeing why you think the power output of a cyclist will change by changing the orientation with respect to gravity?

To be fair, there is this "nugget" that supports your view that preserving hip angle isn't the "be all and end all":
As a rider is rotated about the bottom bracket, the angle between his torso and hips may vary. There is a fundamental connection between the activity of the hip extensor muscles and the muscular torque at the knee joint, but there is no evidence of any sacrifice in propulsive power as the range of motion of the hip joint varies. Moreover, within the confines of the diamond frame, the extent to which a rider will vary his torso angle during normal cycling by changing posture and hand position surpasses the small changes that any rotation about the bottom bracket will have.


Now remember, this is all in context of an article which attempts to describe a method of fitting that will give a good position for both seated and standing riding by putting the rider CG in a good "compromise" position. When talking about TT positions though, I would think standing would be much less of a concern.

One thing I think that needs to be addressed is the idea that by rotating the rider forward about the BB you are aligning the reaction force vector of the legs more vertically, which would lessen the horizontal vector tending to push the rider off the back of the seat...Wouldn't this be an advantage?

Re: Are you sure KB agrees with you?.... 12 years, 5 months ago #2095

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Tom_Anhalt wrote:
Sounds like Keith and I agree, if you ask me.


You think?


Yes. You seem to be focusing on trees. I prefer to look at forests.

What about this quote from that article:
The most important argument I came up with to establish a basis for believeing that KOPS is only an accidental relationship, only has a weak statistical basis and is not physically siginificant is the discussion of the recumbent. In that case, the location of the rider's knees over the pedals is completely different, entirely unrelated to gravity, but the position is as effective in pedaling. This gives you a very simple way to see that the KOPS method has no basis in physics or physiology.


OK, Tom, you're right Keith and I don't agree -> apparently this article implies that Keith vehemently believes that moving forward 25.5cm is a good thing...


And this:
The KOPS rule seems sensible enough; it puts the knee in line with the pedal at maximum pedaling force, which must help, right? Wrong. The KOPS rule of thumb has no biomechanical basis at all. It is, at best, a coincidental relationship that puts the rider somewhere near his or her correct position....The reason the KOPS method is arbitrary is because it relies on the gravitational orientation of a plumb bob. The direction of gravitational force has no bearing on the rider's ability to pedal, except for providing a constraining force at the saddle to counteract the peak portion of the pedal cycle. In analyzing the pedaling motion of a cyclist, it is not useful to think of the thigh as pushing down on the pedal through the knee. It is better to look at the rider's leg and its attachment to the pedal and crank as a system of levers and pivots, and to consider how the pedaling forces and joint torques act on this system.


Point out where I said anything regarding the efficacy of KOPS. Jeez. Forest/Tree? My article states this:

"It should be noted that the relationship between the powerful pushing muscles of the leg/knee and the pedal spindle have not been preserved. Which is better – preserved hip angle, or preserved knee/spindle relationship? Fact of the matter is that “it dependsâ€
-kraig

Re: Faster is faster... 12 years, 5 months ago #2096

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Ashburn wrote:
<snip>


I wish you the best with your experiment, Rick.
-kraig

Re: Are you sure KB agrees with you?.... 12 years, 5 months ago #2097

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Tom_Anhalt wrote:
(snip)


The way I read the KB article...it pretty much says KOPS is a good proxy, but that he has a method that ends up in a similar spot but can specifically help a few people.

A powermeter will help to determine what impact changes in force balancing and weight distribution have on power output (assuming the equipment purchased allows for one to examine different options)considering that it takes a huge change in fore/aft to significantly impact "hip angle" compared to "just bending over".

Cheers, Kirk

Re: Are you sure KB agrees with you?.... 12 years, 5 months ago #2098

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Kirk wrote:
...considering that it takes a huge change in fore/aft to significantly impact "hip angle" compared to "just bending over".

Cheers, Kirk


...and assuming that "hip angle" is even significant at all.

http://www.bobbyjulich.com/julich/photo ... ?image=132

Cheers, Kirk

Re: Faster is faster... 12 years, 5 months ago #2099

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OK, Tom, you're right Keith and I don't agree -> apparently this article implies that Keith vehemently believes that moving forward 25.5cm is a good thing...


Oh...don't get snippy
[quote]Point out where I said anything regarding the efficacy of KOPS. Jeez. Forest/Tree? My article states this:

"It should be noted that the relationship between the powerful pushing muscles of the leg/knee and the pedal spindle have not been preserved. Which is better – preserved hip angle, or preserved knee/spindle relationship? Fact of the matter is that “it dependsâ€

Re: Faster is faster... 12 years, 5 months ago #2100

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Tom_Anhalt wrote:
I still haven't heard any reasoning about what would be changed besides the timing of the force application with respect to an arbitrary reference.


You have, you just seem to want the answer spoon fed to you, IMHO.

Here is what I think you'll find if you did a kinematic analysis of a more forward seat position/higher STA: different hip extension and ankle plantar flexion.

Why? Cause the position is different. Does it matter? It depends - let the PM tell you the answer.

Don't forget, I used an ~11cm forward position and didn't get faster, didn't produce more power -> for me, 11cm forward was fartin' in the wind.

YMMV.
-kraig

You said it 12 years, 5 months ago #2101

kraig wrote:
Don't forget, I used an ~11cm forward position and didn't get faster, didn't produce more power -> for me, 11cm forward was fartin' in the wind.

YMMV.


Notably, you also didn't produce any less, and although you don't have to move well forward to avoid loss of power when assuming a low, aerodynamic position, others - in fact, it seems, most, at least based on numerous pics of people (e.g., Landis) "plugging it" - do. IOW, YMMV - so why not just leave it at that??
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Re: You said it 12 years, 5 months ago #2102

  • Kirk
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Andy Coggan wrote:
kraig wrote:
Don't forget, I used an ~11cm forward position and didn't get faster, didn't produce more power -> for me, 11cm forward was fartin' in the wind.

YMMV.


Notably, you also didn't produce any less, and although you don't have to move well forward to avoid loss of power when assuming a low, aerodynamic position, others - in fact, it seems, most, at least based on numerous pics of people (e.g., Landis) "plugging it" - do. IOW, YMMV - so why not just leave it at that??


Andy, you don't know what you are talking about, as such points are entirely speculation. Cheers, Kirk
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