The importance of crank length to the cyclist.

[FrankDay]

blah blah, the usual stuff

Fergie, do you ever consider some of the weaknesses of any of the studies you throw out? Do you ever consider what was NOT STUDIED in any of these studies you mention? Do you really believe that Martin's opinions definitively address everything that has come up in this thread?

 

[CoachFergie]

Well, feel free to enlighten us Frank. I am always up for a good laugh.

 

[FrankDay]

Can an opinion change dramatically in about a month? Here are two messages I received from Drew Peterson who started really pushing the short crank experiment back in mid-August. He is currently training for the Everest Challenge and Furnace Creek 508. Here is what he wrote on August 17.

"I see it like this now. 115 mm is short 170 is long and 145 is a "tweener" size. I will start at "tweener" size and work down."

He is now riding 110 cranks and has also changed to arch cleats. Here is what he wrote to me today after I pointed out to him what he was thinking a month ago and how our perspective changes based upon our experience.

"So so true. Now 115 seems on the longish side. felt less fatigue at the end of the 130 mile ride today which is a good sign I think."

These two upcoming tests should be a good test of how one can climb on very short cranks. Stay tuned.

 

[Oldman]

The fact that someone very good rides a longer crank is not particularly good evidence that crank length is best for them or that it is best for you. It is simply what they have chosen to do. We don't know what they have done that caused them to choose that crank length. Further, I have theorized that the more power one is putting out the longer the optimum crank length. Therefore, again, the fact that these top pros are riding longer cranks is not evidence that is optimum for you if you are putting out less power than they are, which I suspect you are.

You seriously think that their crank lengths are arrived at by merely choice? There's a place for you in Laura Bachmann's campaign as Social Sciences director then. These guys have all seen more wind tunnel time than a Boeing prototype...

 

[FrankDay]

The fact that someone very good rides a longer crank is not particularly good evidence that crank length is best for them or that it is best for you. It is simply what they have chosen to do. We don't know what they have done that caused them to choose that crank length. Further, I have theorized that the more power one is putting out the longer the optimum crank length. Therefore, again, the fact that these top pros are riding longer cranks is not evidence that is optimum for you if you are putting out less power than they are, which I suspect you are.

You seriously think that their crank lengths are arrived at by merely choice? There's a place for you in Laura Bachmann's campaign as Social Sciences director then. These guys have all seen more wind tunnel time than a Boeing prototype...

Show me the evidence that crank length was a variable with all that wind tunnel time with these top pros. Perhaps it was but I would be surprised since most of their crank sponsors don't make cranks shorter than 165. My sense is these folks spend most of their training time trying to maximize their power then go to the wind tunnel to try to maximize their aerodynamics using whatever crank length they have been training with.

 

[CoachFergie]

I would expect they utilise the research available to them that shows crank length is not a factor in performance and that just as there is more to winning bike races than producing the most power there is more to winning than aerodynamics.

Seeing we have been throwing out anecdotes I have a 16 year old girl (166cm tall) whose father brought her a power meter with 172.5mm cranks so he could use it as well and has a new pair of shoes and upon checking her cleats they were as far forward as possible. In that time she has been setting some new power PBs, won her first stage race and completed her longest race so far. Cleat position, crank length, focused training or maturation? Prob more a very wide combination of things and I would expect many not making a positive contribution.

 

[Oldman]

Show me the evidence that crank length was a variable with all that wind tunnel time with these top pros. Perhaps it was but I would be surprised since most of their crank sponsors don't make cranks shorter than 165. My sense is these folks spend most of their training time trying to maximize their power then go to the wind tunnel to try to maximize their aerodynamics using whatever crank length they have been training with.

Any of those pros and I mean any:can and will have any modifications to equipment they need. That includes a custom bike, cranks, shoes, chamois; you name it. When a rider is paid 1milEuro+ to win the sponsors don't flinch at providing a prototypical version of a product if thats what it takes.

 

[FrankDay]

Any of those pros and I mean any:can and will have any modifications to equipment they need. That includes a custom bike, cranks, shoes, chamois; you name it. When a rider is paid 1milEuro+ to win the sponsors don't flinch at providing a prototypical version of a product if thats what it takes.

Well, I know for a fact that several years ago one of those team leader million Euro men was advised by a coach to move to cranks in the 150mm range. Instead, he chose to shorten his cranks about 2.5 mm. Why? Who knows. People don't always do what is in their own best self interest even though they know better. It is especially difficult to convince people at the top of something that there is a better way.

Anyhow, crank length either makes a big difference, a small difference, or no difference. I happen to think it makes a big difference. I have put forth my reasons why I believe so and some anecdotal evidence to support my contention. But, suppose you folks are right and crank length makes little or no difference. If that is the case, why on earth do you care about this discussion?

 

[CoachFergie]

Anyhow, crank length either makes a big difference, a small difference, or no difference. I happen to think it makes a big difference. I have put forth my reasons why I believe so and some anecdotal evidence to support my contention. But, suppose you folks are right and crank length makes little or no difference. If that is the case, why on earth do you care about this discussion?

I must have blinked when you supplied this supporting evidence.

The Martin and McDaniel studies show there is no advantage from manipulating crank length.

Why do I care. Because I get asked questions on a daily basis...

Do I need to adopt this position on the bike?
Will a power meter make me a faster bike rider?
Do I need to take this supplement?
Should I buy a disc wheel or are my deep section wheels sufficient?

And I like to respond with something a little more substantial than "well Alice went from 170mm cranks to 172.5mm cranks and when she put her cleats on her new shoes she put them way forward and she won the big race last week (true story BTW) so you better do the same"!

 

[FrankDay]

The Martin and McDaniel studies show there is no advantage from manipulating crank length.

Gee, I thought Martin found no statistically significant power difference when changing crank length (within certain limits). That is not quite the same, IMHO, as showing no possible advantage to the change, as you allude.

 

[CoachFergie]

Didn't recall saying no possible advantage.

The max .5% that Martin suggested is not worth dropping a grand on adjustable cranks, having to lift the saddle, shunt it back, lift the bars when there are numerous training manipulations that have significant results like short intervals training that in one study saw a 100% improvement in time to exhaustion after 2 weeks of training (Burgomaster etal, 2005).

 

[FrankDay]

Didn't recall saying no possible advantage.

The max .5% that Martin suggested is not worth dropping a grand on adjustable cranks, having to lift the saddle, shunt it back, lift the bars when there are numerous training manipulations that have significant results like short intervals training that in one study saw a 100% improvement in time to exhaustion after 2 weeks of training (Burgomaster etal, 2005).

The "max .5% that Martin suggested" was not a max at all. It was simply the difference in power he saw between 145 and 170. It is your narrow focus on power being the best measure of performance that keeps leading you astray. As this thread has alluded to (and you continue to ignore), one of the major theoretical advantages of shorter cranks comes from the potentially improved aerodynamic position achievable with shorter cranks. It is possible with improved aerodynamics that racing performance could improve even if power dropped some with shorter cranks. The fact that Martin showed a potential 0.5% power improvement going from 170 to 145 makes the change potentially even more powerful. Your statement that "The Martin and McDaniel studies show there is no advantage from manipulating crank length" simply ignores the facts and presents an misinterpretation of the facts that fits your needs for this argument.

And, whether a potential 0.5% improvement in power (let alone the other potential improvements) is worth $1,000 and other inconveniences (as if it was necessary to spend that much to make these changes) or so is really a question for each individual to decide, not you to decide for them, don't you think?

 

[Oldman]

The "max .5% that Martin suggested" was not a max at all. It was simply the difference in power he saw between 145 and 170. It is your narrow focus on power being the best measure of performance that keeps leading you astray. As this thread has alluded to (and you continue to ignore), one of the major theoretical advantages of shorter cranks comes from the potentially improved aerodynamic position achievable with shorter cranks. It is possible with improved aerodynamics that racing performance could improve even if power dropped some with shorter cranks. The fact that Martin showed a potential 0.5% power improvement going from 170 to 145 makes the change potentially even more powerful. Your statement that "The Martin and McDaniel studies show there is no advantage from manipulating crank length" simply ignores the facts and presents an misinterpretation of the facts that fits your needs for this argument.

And, whether a potential 0.5% improvement in power (let alone the other potential improvements) is worth $1,000 and other inconveniences (as if it was necessary to spend that much to make these changes) or so is really a question for each individual to decide, not you to decide for them, don't you think?

The highlighted part is a possibility. That's where subtle, individual changes come into play and most forum lurkers are looking for measurable proof that radical departures actually work before wrecking their clients' position. You should offer up some research product to Fergie and others with some incentives to prove your point. Convincing tri-athletes to spend ridiculous money for radical measures isn't proof.

 

[FrankDay]

The highlighted part is a possibility. That's where subtle, individual changes come into play and most forum lurkers are looking for measurable proof that radical departures actually work before wrecking their clients' position. You should offer up some research product to Fergie and others with some incentives to prove your point. Convincing tri-athletes to spend ridiculous money for radical measures isn't proof.

I presented a theoretical argument. You don't like it because I can't prove my thoughts. If you are expecting proof (beyond Martin, which seems pretty compelling to me) before you change you are going to have to wait a long time and if I am right you will most surely be 10-15 years behind everyone else. I doubt any has yet "proven" that the fosbury flop high jumping technique is superior to the old barrel role. Yet, the whole world has moved on. Scientific proof of superiority is rarely forthcoming in sports performance theory.

 

[FrankDay]

Convincing tri-athletes to spend ridiculous money for radical measures isn't proof.

Triathlete's aren't the only species spending money for minimal or no benefit.

How much will the weight weenies spend to save a few grams? Yet, wieght savings usually have tiny potential benefits (much less than Martin's 0.5% potential power benefit) and if saving those grams negatively influence stiffness and power transmission, such changes could negatively affect performance.

How many cyclists have spent $1-5,000 on power meters even though there is zero scientific proof this device offers any competitive advantage? In fact, the only study on the subject showed there is no competitive benefit yet the device is still highly touted.

As I stated before, scientific proof supporting pretty much every training/racing theory is lacking. People pull out this argument simply to disparage ideas they don't like when they have no other good evidence to support their argument.

 

[CoachFergie]

one of the major theoretical advantages of shorter cranks comes from the potentially improved aerodynamic position achievable with shorter cranks.

And it remains a theory till some form of proof is provided. There are more, and cheaper ways of improving aerodynamics than running shorter cranks.

 

[CoachFergie]

I presented a theoretical argument. You don't like it because I can't prove my thoughts. If you are expecting proof (beyond Martin, which seems pretty compelling to me) before you change you are going to have to wait a long time and if I am right you will most surely be 10-15 years behind everyone else. I doubt any has yet "proven" that the fosbury flop high jumping technique is superior to the old barrel role. Yet, the whole world has moved on. Scientific proof of superiority is rarely forthcoming in sports performance theory.

Strawman.

Every year one Biomechanics text covers the difference between Fosbury Flop and previous methods.

 

[FrankDay]

Strawman.

Every year one Biomechanics text covers the difference between Fosbury Flop and previous methods.

Cool. But, where is the scientific proof of one being superior to the other? Show us the study. That was the point.

 

[FrankDay]

There are more, and cheaper ways of improving aerodynamics than running shorter cranks.

My contention is that the potential of shorter cranks is additive to all of those other methods. Using other methods does not preclude also going to shorter cranks to see even further improvement.

 

[CoachFergie]

Triathlete's aren't the only species spending money for minimal or no benefit.

People have been trying to buy improved performance for years.

How much will the weight weenies spend to save a few grams? Yet, wieght savings usually have tiny potential benefits (much less than Martin's 0.5% potential power benefit) and if saving those grams negatively influence stiffness and power transmission, such changes could negatively affect performance.

Strawman.

How many cyclists have spent $1-5,000 on power meters even though there is zero scientific proof this device offers any competitive advantage? In fact, the only study on the subject showed there is no competitive benefit yet the device is still highly touted.

Strawman. It staggers me that people can't tell the difference between a measurement tool and a performance enhancement method. Seeing aerodynamics is a claimed benefit of running shorter cranks how do people propose these measures are validly and reliably measured?

As I stated before, scientific proof supporting pretty much every training/racing theory is lacking. People pull out this argument simply to disparage ideas they don't like when they have no other good evidence to support their argument.

Burgomaster etal (2008) found a 100% improvement in cycle to exhaustion from a 2 week period of short interval training.

 

[CoachFergie]

Cool. But, where is the scientific proof of one being superior to the other? Show us the study. That was the point.

Athletes and coaches don't need a published study when one can see a valid and reliable measure of performance. For the Fosbury Flop it is centimetres jumped.

How does one make a valid and reliable measure of aerodynamics and power delivery while pedalling in a position without a wind tunnel and a power meter?

 

[FrankDay]

Athletes and coaches don't need a published study when one can see a valid and reliable measure of performance. For the Fosbury Flop it is centimetres jumped.

How does one make a valid and reliable measure of aerodynamics and power delivery while pedalling in a position without a wind tunnel and a power meter?

Yes, how did cyclists make these decisions before these were available? They couldn't have been very good, I guess, and this generation must be much better, I guess, because of the ready availability of these tools. That should be easy to prove.

Oh and where is the scientific proof that using wind tunnels and a power meter result in better results than not?

The scientific proof argument is simply useful to people like yourself to disparage ideas you disagree with and but must be conveniently disregarded when you are pushing ideas you agree with.

 

[CoachFergie]

Yes, how did cyclists make these decisions before these were available? They couldn't have been very good, I guess, and this generation must be much better, I guess, because of the ready availability of these tools. That should be easy to prove.

The same way that anything was measured till a better measurement tool was developed. Anyone can do the maths and determine the power required to ride a bike but now we have a tool that does it for us.

Oh and where is the scientific proof that using wind tunnels and a power meter result in better results than not?

It staggers me that people can't tell the difference between a measurement tool and a performance enhancement method.

 

[FrankDay]

The same way that anything was measured till a better measurement tool. Anyone can do the maths and determine the power required to ride a bike but now we have a tool that does it for us.

Where is the proof it is a better measurement tool if the "better" one is interested in is "better" racing. The only "better" you can argue for the PM is one actually gets a power number.

It staggers me that people can't tell the difference between a measurement tool and a performance enhancement method.

It staggers me that people are so concerned about a number they can compare with each other over how much they can improve their racing, which is really about how fast they can go. Right now on slowtwitch there is a thread with people marveling how Michael Weiss averaged 370 watts for the half IM course. Yet, he didn't even have the fastest bike split. Power is simply a number. By itself it really doesn't say much about how one will actually race. Power is simply the simplest thing to know so that is what people concentrate on. This thread tried to get us thinking about some of the other aspects of racing. Looks like it failed at least as regards you.

 

[CoachFergie]

Where is the proof it is a better measurement tool if the "better" one is interested in is "better" racing. The only "better" you can argue for the PM is one actually gets a power number.

That is why one buys a power meter to get that number so they can quantify performance in a valid and reliable way.

It staggers me that people are so concerned about a number they can compare with each other over how much they can improve their racing, which is really about how fast they can go. Right now on slowtwitch there is a thread with people marveling how Michael Weiss averaged 370 watts for the half IM course. Yet, he didn't even have the fastest bike split. Power is simply a number.

A tool isn't bad because people choose to misinterpret the data or don't bother to learn what the numbers mean.

By itself it really doesn't say much about how one will actually race. Power is simply the simplest thing to know so that is what people concentrate on. This thread tried to get us thinking about some of the other aspects of racing. Looks like it failed at least as regards you.

Actually says quite a bit about how well someone will race. Pointless comparisons with others aside if one knows the demands of the racing one can use the power meter to show them they are in the ball park in terms of their general conditioning and specific fitness.

I had a rider achieve two of his best results in his last two races and his power was down across the board. Guess that finally means the coaching to race smarter is sinking in.