The importance of crank length to the cyclist.

[CoachFergie]

You never answer questions, instead you try to wriggle your way out with a vague reply. You say Obree explained it, how does it differ from natural pedaling.

How vague is saying neither way of explaining application of power across the top of the stroke improving performance is unsupported by the data?

Very sad seeing the technology to test the hypothesis has been available for 30 years. Why have you not put your money where your mouth is?

 

[FrankDay]

New anecdote to report. User just reported he has been experimenting with crank length on his basic PowerCranks that will go as short as 145mm. He is a triathlete and used to racing on 175mm cranks. He was having trouble adapting to the PowerCranks at the 175mm length (even when he went "short" to 165) and I suggested that he go as short as possible (145). He agreed after he heard my rational. After just a few weeks of on the 145mm PowerCranks he is reporting he is definitely faster on the 145mm PowerCranks than he is on his 175mm regular cranks. Now his dilemma is to figure out if the improvement is the crank length or the PowerCranks or both. That should be easy to do by simply getting some 145 mm regular cranks and comparing again. My guess is it is a little of both.

 

[FrankDay]

Another anecdote I heard today. A bike fitter I know just told me he did two things for someone having a lot of back pain, he shortened his cranks to 150 (he wanted to go a little shorter but the rider couldn't find compatible cranks shorter) and he widened his stance. Not only did his back pain go away he improved his time up a local climb by 18 minutes. PowerCranks not involved in this one.

 

[FitSsikS]

Ok, I'm jumping in rather late on this one.

I can see power cranks being used by exercise physiologists to test work outputs at various crank lengths.

...and that is all.

Just like rpm there is an optimal crank length for each athlete with the latter being related to femur and foot length.

On a sarcastic note, just imagine how fast Usain Bolt would be if he limited his training stride by tying his ankles together.

 

[FrankDay]

…there is an optimal crank length for each athlete with the latter being related to femur and foot length.

Would you have any science to support that statement? In your opinion, exactly how is optimum crank length related to femur and foot length and what is your formula and where did it come from? Thanks for your participation.

 

[42x16ss]

Would you have any science to support that statement? In your opinion, exactly how is optimum crank length related to femur and foot length and what is your formula and where did it come from? Thanks for your participation.

That's a good question, one you might want to answer yourself in fact. Since you are the one telling us that our 170 - 172.5 mm cranks are the wrong length and all

 

[CoachFergie]

New anecdote to report. User just reported he has been experimenting with crank length on his basic PowerCranks that will go as short as 145mm. He is a triathlete and used to racing on 175mm cranks. He was having trouble adapting to the PowerCranks at the 175mm length (even when he went "short" to 165) and I suggested that he go as short as possible (145). He agreed after he heard my rational. After just a few weeks of on the 145mm PowerCranks he is reporting he is definitely faster on the 145mm PowerCranks than he is on his 175mm regular cranks. Now his dilemma is to figure out if the improvement is the crank length or the PowerCranks or both. That should be easy to do by simply getting some 145 mm regular cranks and comparing again. My guess is it is a little of both.

Without power meter data it is just a guess.

 

[CoachFergie]

Another anecdote I heard today. A bike fitter I know just told me he did two things for someone having a lot of back pain, he shortened his cranks to 150 (he wanted to go a little shorter but the rider couldn't find compatible cranks shorter) and he widened his stance. Not only did his back pain go away he improved his time up a local climb by 18 minutes. PowerCranks not involved in this one.

And just as meaningless as the post by you that preceded it. Can see why you don't practice medicine any more.

 

[CoachFergie]

Would you have any science to support that statement? In your opinion, exactly how is optimum crank length related to femur and foot length and what is your formula and where did it come from? Thanks for your participation.

That's pretty rich Frank. You of all people asking for evidence

 

[FitSsikS]

Life is short, both reading my posts and training with PowerCranks will make it seem longer

I have tried and I can only read the above statement in a negative way.

If you meant it that way then the joke is on us and I can only add, "as does sitting through a root canal."

Well played.

 

[hiero2]

I just popped in to see how this long-running discussion was faring. Especially since it never struck me as a well-mannered discussion. I would like to add this, though - please be more careful of what you say. Any of these three posts could be construed as a personal attack. And, you know personal attacks are a no-no.

I believe they are attempting to be humorous - but I would suggest avoiding such remarks as being non-productive.

And just as meaningless as the post by you that preceded it. Can see why you don't practice medicine any more.

That's pretty rich Frank. You of all people asking for evidence

I have tried and I can only read the above statement in a negative way.

If you meant it that way then the joke is on us and I can only add, "as does sitting through a root canal."

Well played.

 

[FitSsikS]

I just popped in to see how this long-running discussion was faring. Especially since it never struck me as a well-mannered discussion. I would like to add this, though - please be more careful of what you say. Any of these three posts could be construed as a personal attack. And, you know personal attacks are a no-no.

I believe they are attempting to be humorous - but I would suggest avoiding such remarks as being non-productive.

When I saw "Life is short, both reading my posts and training with PowerCranks will make it seem longer " at the bottom of FD's posts I thought there was a chance he was having us on.

 

[CoachFergie]

I just popped in to see how this long-running discussion was faring. Especially since it never struck me as a well-mannered discussion. I would like to add this, though - please be more careful of what you say. Any of these three posts could be construed as a personal attack. And, you know personal attacks are a no-no.

I believe they are attempting to be humorous - but I would suggest avoiding such remarks as being non-productive.

Fair call. Also fair to say Frank is well know for starting these spam threads which are really just a marketing exercise for his product. A way to circumvent paying for advertising which I assume keeps this site open.

 

[FrankDay]

That's a good question, one you might want to answer yourself in fact. Since you are the one telling us that our 170 - 172.5 mm cranks are the wrong length and all

Well, if you had actually read the entire thread you might have seen this chart taken from about the only scientific study on the subject of crank length (that I know of) done by Martin out of the University of Utah.

I know it isn't a lot but at least it is something. Now show me what you have to back up your statement.

 

[CoachFergie]

I know it isn't a lot but at least it is something. Now show me what you have to back up your statement.

But it's not a significant something and Dr Martin has gone to great lengths to explain that the importance of crank length for the shortest or tallest riders equals a 0.5% improvement if they are riding 170mm cranks. So not very important at all.

 

[hiero2]

When I saw "Life is short, both reading my posts and training with PowerCranks will make it seem longer " at the bottom of FD's posts I thought there was a chance he was having us on.

Could be! I got what you said, I like the humor angle you caught on that comment. I was just noting a potential for misunderstanding, and felt a note could be helpful in this case.

Cheers!
H

 

[CoachFergie]

... this chart taken from about the only scientific study on the subject of crank length (that I know of)...

Ignorance is bliss. This presentation has been brought up in the thread several times...

http://www.plan2peak.com/files/32_article_JMartinCrankLengthPedalingTechnique.pdf

So you were saying about the importance of crank length?

 

[42x16ss]

Well, if you had actually read the entire thread you might have seen this chart taken from about the only scientific study on the subject of crank length (that I know of) done by Martin out of the University of Utah.

I know it isn't a lot but at least it is something. Now show me what you have to back up your statement.

I have been following this thread, for quite a while too. I still haven't seen any evidence to make me want to switch.

If you go back about 30 pages you'll find I suggested that you could come up with a convincing argument for or against by simply getting a powertap wheel and testing power output on one of your bikes with adjustable length cranks - but you won't even do that (IIRC you actually asked why I don't do it!)

You keep forgetting that you are challenging the norm, so therefore the ball is heavily in your court...

If someone comes up with a ground breaking study proving a substantial improvement with shorter cranks, backed up with real, peer reviewed data, then I and many others will happily drop 30mm or so from our cranks. Until then, I think you should understand our scepticism.

 

[fortysixandtwo]

How is this thread not locked in the name of science? I was poking around for some information on crank length and came across this and waded through about 30 pages before I realized it was a poor attempt to sell an unproven product. The attempt to sell a product in a thread thinly veiled as "discussion" has to be a violation of this forum's TOS. If I proposed that running a 70t chainring made you go faster, and then spammed the forum with only anecdotal evidence to promote my product, I think we'd all be in agreement the thread should be closed and I should be banned. C'mon on mods, shut it down.

 

[FrankDay]

I have been following this thread, for quite a while too. I still haven't seen any evidence to make me want to switch.

If you go back about 30 pages you'll find I suggested that you could come up with a convincing argument for or against by simply getting a powertap wheel and testing power output on one of your bikes with adjustable length cranks - but you won't even do that (IIRC you actually asked why I don't do it!)

You keep forgetting that you are challenging the norm, so therefore the ball is heavily in your court...

If someone comes up with a ground breaking study proving a substantial improvement with shorter cranks, backed up with real, peer reviewed data, then I and many others will happily drop 30mm or so from our cranks. Until then, I think you should understand our scepticism.

But, the main benefit of going shorter for most is not more power but the ability to get better aerodynamics for the time trialist. How on earth do you do that by "simply getting a powertap wheel and testing power output on one of your bikes with adjustable length cranks."

Further, isn't that essentially what Martin did in his study? It would appear that if he had 2-3 times more subjects in that study he would have reached a statistically significant difference between 145 and 170, what would you be saying then? Anyhow, why do I need to repeat Martin's study with N=1?

We are all different when it comes to how much "evidence" it takes to make us change what we are doing. The lack of convincing evidence either way is all the more reason to discuss a subject. Perhaps such discussions will get some researchers off their bottoms and get some good evidence to definitely answer the question. Until then those who are unwilling to experiment on themselves to see what is best for them are "guessing" as to what is best for them.

 

[hiero2]

How is this thread not locked in the name of science? I was poking around for some information on crank length and came across this and waded through about 30 pages before I realized it was a poor attempt to sell an unproven product. The attempt to sell a product in a thread thinly veiled as "discussion" has to be a violation of this forum's TOS. If I proposed that running a 70t chainring made you go faster, and then spammed the forum with only anecdotal evidence to promote my product, I think we'd all be in agreement the thread should be closed and I should be banned. C'mon on mods, shut it down.

You know - I had a similar thought myself, a long time ago, before I was mod. I'll take a look at this again, I will. However, in the meantime - remember we (as in you, I, or Joe Shmoe) can also start threads to discuss the topic.

 

[Alex Simmons/RST]

You know - I had a similar thought myself, a long time ago, before I was mod. I'll take a look at this again, I will. However, in the meantime - remember we (as in you, I, or Joe Shmoe) can also start threads to discuss the topic.

You could also think of it as the garbage collection thread. Put a lid on it and the trash will start to pile up elsewhere....

 

[FrankDay]

How is this thread not locked in the name of science?

You know - I had a similar thought myself, a long time ago, before I was mod. I'll take a look at this again, I will. However, in the meantime - remember we (as in you, I, or Joe Shmoe) can also start threads to discuss the topic.

You know, if a thread is to be locked "in the name of science" you would only be able to discuss pretty much nothing. So much for the forum. If everything were scientifically proven there would be no need to discuss anything. Can you name one thing in cycling (aside from, perhaps, if one trains more one is likely to get better as long as they don't get injured doing so) in which one idea has been scientifically proven to be superior to another. I am not aware of any scientific proof that doing any of the following will make one a better or faster cyclist:

1. getting and using a power meter in training or racing
2. getting and using a HRM in training or racing.
3. getting a coach
4. using any particular supplement
5. using or not using strength training as a supplement
6. getting a bike fit let alone that one bike fit philosophy is superior to another
7. the superiority of any of the myriad crank length formula's out there
8. etc., etc., etc.

Scientific proof of any concept as complicated as bicycle racing is very difficult to obtain because of the need to control for all of the variables. The fact that scientific proof does not exist is not proof that a concept is invalid. So, we continue to see post after post of someone coming to this site saying "what is the best thing I can do to get fast?" and one of the more common responses is "get a power meter". No one objects to the "lack of science" in those threads because the answers conform to the current, unproven but generally accepted, bias

It just blows me away that some of these folks get their panties in a bunch when they see a "scientific study" on my device involving part-time use lasting 5-6 weeks that doesn't follow the manufacturers directions. I will admit that anyone who expects to see benefit from training with PowerCranks in 5-6 weeks of part-time use before they give up on them would be better off not getting them at all. Some here consider those studies "scientific proof" of the inadequacy of the product. I don't. Neither do thousands of very happy users. But, those happy users don't constitute scientific proof. Neither do the happy users of any other training or racing device.

Anyhow, I am somewhat appalled that you, as a moderator, would even consider this request based upon the science. These threads would be much better (I doubt we would be above 100 posts and off the front page a long time ago) if you would simply ban those who only know how to respond with personal attacks. Where is the science there? Your consideration of this is especially troubling in view of the fact that I have been told that several of the "big boys" either are manufacturing shorter cranks now (Rotor) or expect to soon be manufacturing shorter cranks. Something must be making them do this but, I suspect, it sure as heck is not the naysayers who hang out here. Will you still ban crank length discussions when Shimano starts making 150 mm cranks? Or, is it only my input that is troubling?

 

[CoachFergie]

You know, if a thread is to be locked "in the name of science" you would only be able to discuss pretty much nothing.

Would have to look at the history of the poster. You have started numerous Spam threads in various forums and have been banned from several forums.

1. getting and using a power meter in training or racing

There is actually plenty of evidence that a power meter does indeed measure power.

2. getting and using a HRM in training or racing.

Ditto

3. getting a coach

Again a testable hypothesis and a large amount of research on various coaching syles in just the same way there is a volume of research on different teaching approaches.

4. using any particular supplement

Huge volume of research. BJSM publish a review of current supplement research in every issue.

5. using or not using strength training as a supplement

Again a volume of research.

6. getting a bike fit let alone that one bike fit philosophy is superior to another

Okay, not a huge amount of research but most aspects have been covered to some degree.

7. the superiority of any of the myriad crank length formula's out there

Again very well covered, but I guess ignorance is bliss.

Scientific proof of any concept as complicated as bicycle racing is very difficult to obtain because of the need to control for all of the variables. The fact that scientific proof does not exist is not proof that a concept is invalid. So, we continue to see post after post of someone coming to this site saying "what is the best thing I can do to get fast?" and one of the more common responses is "get a power meter". No one objects to the "lack of science" in those threads because the answers conform to the current, unproven but generally accepted, bias

Again well proven that a power meter, does indeed measure power in much the same way a scale measures weight, a HR monitor does measure heart rate and a stopwatch measures time.

It just blows me away that some of these folks get their panties in a bunch when they see a "scientific study" on my device involving part-time use lasting 5-6 weeks that doesn't follow the manufacturers directions. I will admit that anyone who expects to see benefit from training with PowerCranks in 5-6 weeks of part-time use before they give up on them would be better off not getting them at all. Some here consider those studies "scientific proof" of the inadequacy of the product. I don't. Neither do thousands of very happy users. But, those happy users don't constitute scientific proof. Neither do the happy users of any other training or racing device.

Plenty of evidence that physiological adaptations to exercise occur in a matter of seconds to hours and huge adaptations can be made in weeks and that after 5-6 weeks most regimes start to plateau and the training stimulus needs to be varied.

Or, is it only my input that is troubling?

Look at the pattern of offending!

 

[M Sport]

These threads would be much better (I doubt we would be above 100 posts and off the front page a long time ago) if you would simply ban those who only know how to respond with personal attacks.

The common denominator in the personal attacks is you, Frank. That's why you have been banned from nearly every cycling message board you have tried to pedal your GimmickCranks in.