The pedaling technique thread

[CoachFergie]

Nothing about independent cranks change the mechanical constraints to pedaling. All the mechanical constraints of a pedaling system do is constrain the foot to a circular motion. That is the same for both regular and independent cranks. What independent cranks demonstrate is that pedaling technique is not pre-ordained by God and if there are variations in technique possible then variations in effectiveness are probable and it should behoove the curious, serious, cyclist to seek out the technique that is best. If you don't care to that is your choice.

Easily testable with any power meter and due to the low level of skill required to learn either type of pedalling one should easily expect to see a difference in performance in a training intervention of 5-6 weeks. But the studies authored by Luttrell, Bohm, Williams, Burns, Sperlich etc did not find this with a very adequate training stimulus compared to a control group.

 

[King Boonen]

Nothing about independent cranks change the mechanical constraints to pedaling. All the mechanical constraints of a pedaling system do is constrain the foot to a circular motion. That is the same for both regular and independent cranks. What independent cranks demonstrate is that pedaling technique is not pre-ordained by God and if there are variations in technique possible then variations in effectiveness are probable and it should behoove the curious, serious, cyclist to seek out the technique that is best. If you don't care to that is your choice.

Yes they do. They remove the constraint of the feet having to be at 180 degrees from each other during pedaling.

 

[acoggan]

Perhaps you missed this screen shot from a 2d gen PM (iCranks) that is actually measuring the total power and showing how much of it is coming from forward force and how much is lost due to negative force. At this point this rider would gain 17 watts by simply eliminating the negative force.

Increasing the forward torque on the crank will always result in an increase in power - the sign (i.e., whether you go from negative to less negative, from negative to positive, or from positive to more positive) is irrelevant.

Why is this important? Because negative torque on the upstroke usually doesn't represent wasted energy (i.e., it normally arises from inertial and gravitational effects, not active muscle contraction), meaning that there's no more opportunity there to increase power than anywhere else in the crank cycle.

"The key to going faster is to stomp on the pedals harder." - John Cobb

 

[coapman]

"The key to going faster is to stomp on the pedals harder." - John Cobb

This means, like yourself he does not believe there is anything to be gained by unweighting. Where exactly between 12 and 3 o'c did he say this stomp should start, not forgetting the earlier you start the more of that force is wasted, making it ok sprinting but most inefficient for time trials.

 

[FrankDay]

Increasing the forward torque on the crank will always result in an increase in power - the sign (i.e., whether you go from negative to less negative, from negative to positive, or from positive to more positive) is irrelevant.

Why is this important? Because negative torque on the upstroke usually doesn't represent wasted energy (i.e., it normally arises from inertial and gravitational effects, not active muscle contraction), meaning that there's no more opportunity there to increase power than anywhere else in the crank cycle.

"The key to going faster is to stomp on the pedals harder." - John Cobb

Dr. Coggan, for all your book learnin' you sure say some silly stuff. So let me make sure I got this straight before I put out just a thing or two that might be a tad wrong about the above analysis.

You are saying that because the gravity and inertial effects cancel each other out that, as long as the rider is not doing anything active to put back pressure on the upstroke, there is zero benefit to doing anything on the backstroke? So, lets assume that a leg weighs 30 lbs. If the rider did absolutely zero on the back stroke there would be 30 lbs max back force on the upstroke due to gravity plus, maybe, 5 lbs of additional force due to inertial effects (that depends on the cadence). According to your analysis, as I read it, it does the rider no good to do anything back there, unweighting to reduce the back force to 20 lbs, 10 lbs, 1 lb, or even trying to apply some positive force. Is that correct?

 

[JayKosta]

...
Because negative torque on the upstroke usually doesn't represent wasted energy (i.e., it normally arises from inertial and gravitational effects, not active muscle contraction), meaning that there's no more opportunity there to increase power than anywhere else in the crank cycle.
...

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If there isn't any active muscle constraction on the upstroke, then perhaps the upstroke might offer an opportunity for additional (or at least, less non-negative) torque by applying some amount of effective muscle action.

Jay Kosta
Endwell NY USA

 

[acoggan]

Dr. Coggan, for all your book learnin' you sure say some silly stuff. So let me make sure I got this straight before I put out just a thing or two that might be a tad wrong about the above analysis.

You are saying that because the gravity and inertial effects cancel each other out that, as long as the rider is not doing anything active to put back pressure on the upstroke, there is zero benefit to doing anything on the backstroke? So, lets assume that a leg weighs 30 lbs. If the rider did absolutely zero on the back stroke there would be 30 lbs max back force on the upstroke due to gravity plus, maybe, 5 lbs of additional force due to inertial effects (that depends on the cadence). According to your analysis, as I read it, it does the rider no good to do anything back there, unweighting to reduce the back force to 20 lbs, 10 lbs, 1 lb, or even trying to apply some positive force. Is that correct?

"Increasing the forward torque on the crank will always result in an increase in power"

IOW, unless the rider is actively resisting the rising pedal, there's no more "opportunity" on the upstroke than on the downstroke.

 

[acoggan]

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If there isn't any active muscle constraction on the upstroke, then perhaps the upstroke might offer an opportunity for additional (or at least, less non-negative) torque by applying some amount of effective muscle action.

No more opportunity than on the downstroke.

 

[FrankDay]

No more opportunity than on the downstroke.

So, you are saying that anything that can be done on the upstroke (or at the top or bottom) can be done just as well on the down stroke (or, even, a portion of the down stroke) without any penalty or restriction, is that correct? Therefore, by this line of thinking, there is absolutely nothing to be gained by trying to apply any force at any other part of the pedaling circle beyond the "natural" pushing motion. Is that correct?

 

[FrankDay]

Yes they do. They remove the constraint of the feet having to be at 180 degrees from each other during pedaling.

But, the motion of each foot is still constrained to the same circle whether the cranks are at 180º or not. And, since most people ride independent cranks with them at 180º as their preferred method of using them (except when doing special drills) that "removed constraint" is a moot removal.

 

[JayKosta]

No more opportunity than on the downstroke.

---------------
OK, got it -
Just as there is opportunity to increase torque and power on the downstroke, there is similar opportunity to increase on any other sector of the entire crank rotation.

Jay Kosta
Endwell NY USA

 

[CoachFergie]

Yes but increase torque in one area and you lose in others so why not use the downstroke where the quadriceps and gluteal muscles are the main muscle groups as opposed to small muscle groups like the hip flexors. This concept of sharing the load over more muscles or that you can generate more torque around the pedal stroke through special techniques (Obree, "like kicking a soccer ball over the top" or Carmichael "throwing your knee over the handlebars") has never been proven more effective. It's very easy to test with a power meter. Training adaptations occur very quickly so a performance test before and after 2-4 weeks will easily show if you are on track.

 

[coapman]

Yes but increase torque in one area and you lose in others so why not use the downstroke where the quadriceps and gluteal muscles are the main muscle groups as opposed to small muscle groups like the hip flexors. This concept of sharing the load over more muscles or that you can generate more torque around the pedal stroke through special techniques (Obree, "like kicking a soccer ball over the top" or Carmichael "throwing your knee over the handlebars") has never been proven more effective. It's very easy to test with a power meter. Training adaptations occur very quickly so a performance test before and after 2-4 weeks will easily show if you are on track.

You would not see Anquetil kicking a ball over the top, this is a sample of what pedalling without a dead spot sector around TDC looks like:: http://video-hned.com/video/0nn20Ixn0Mc/RECORD-DELL-ORA-JACQUES-ANQUETIL-1967-AL-VIGORELLI.html

 

[CoachFergie]

You would not see Anquetil kicking a ball over the top, this is a sample of what pedalling without a dead spot sector around TDC looks like:: http://video-hned.com/video/0nn20Ixn0Mc/RECORD-DELL-ORA-JACQUES-ANQUETIL-1967-AL-VIGORELLI.html

Yes very inspiring but certainly not the basis of scientific discussion. Your hypothesis is very easily testable with any power meter. You should stop hiding behind lame excuses and prove us all wrong. You did say anyone could almost double their power!

 

[JayKosta]

Yes but increase torque in one area and you lose in others ...

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Is this your opinion, or do you know of documented studies that confirm it?

I think that I know what you mean, but your statement is not precisely worded. At 'face value' it would mean that increasing power on the downstroke would cause a loss of power in other sectors.

Jay Kosta
Endwell NY USA

 

[FrankDay]

"Increasing the forward torque on the crank will always result in an increase in power"

IOW, unless the rider is actively resisting the rising pedal, there's no more "opportunity" on the upstroke than on the downstroke.

Reason #1 why this is complete BS.

Let's presume that a rider generates all of his power on the downstroke and does nothing on the upstroke (minus 20 lbf average force on the pedals). And, let's say he is maxed out, generating 400 watts (meaning 800 watts on the downstroke for half the time) with an average force on the pedals of 120 lbf during the downstroke 90 times a minute. (This gives him an average force on the pedals for the entire circle of 50 lbf)

Now, let's presume this rider wants to improve 5%. Is he more likely to improve by improving his push to 125 lbf 90 times a minute (increasing to 840 watts on the downstroke) or learning how to unweight 5 lbf on the upstroke (to a minus 15 lbf average on the upstroke - generating 40 watts on the upstroke) 90 times a minute?

So, putting it another way, is it easier to improve a muscle that is working maximally (or near maximally) and extra 10% or to start using a muscle that is not being used at all (or being totally underutilized) to generate improvement? Submit your votes folks.


Reason # 2 to follow soon if it isn't obvious what is wrong with this thinking.

 

[sciguy]

You seem to be working from the premise that a rider's power output is limited by their muscular strength. While this may well be the case with pure sprinters, a quick look at the legs of Chris Froome, Brad Wiggins, Chris Hornor or a host of other elite riders might quickly dispel that line of reasoning for some of us.

YMMV,

Hugh

 

[FrankDay]

You seem to be working from the premise that a rider's power output is limited by their muscular strength. While this may well be the case with pure sprinters, a quick look at the legs of Chris Froome, Brad Wiggins, Chris Hornor or a host of other elite riders might quickly dispel that line of reasoning for some of us.

YMMV,

Hugh

I am not working from any "premise" per se. Dr. Coggan stated that it didn't matter what the case that improvements could come equally from anywhere around the circle as long as the rider wasn't actively resisting on the upstroke. I am simply point out one example whereby this probably isn't the case. If this doesn't convince you that this argument is complete BS I will move on to other examples. The argument is complete BS regardless of the situation, even when all the muscles are working equally (in relationship to their capability).

As I said earlier, a lot of book learning in AC's brain, but it isn't being utilized very well when it comes to this argument.

 

[CoachFergie]

So, putting it another way, is it easier to improve a muscle that is working maximally (or near maximally) and extra 10% or to start using a muscle that is not being used at all (or being totally underutilized) to generate improvement?

As Hugh pointed out would have to show the muscle was working maximally. A flying 200m is ridden at only 90-95%% of maximal power. A road time trial at 15-25% of maximal power. So your assumption of a muscle working maximally is incorrect.

 

[CoachFergie]

Yes, could be worded better.

-----
Is this your opinion, or do you know of documented studies that confirm it?

Bohm 2008 did find...

Abstract SmartCranks use a free running bearing to
promote independent pedal work by each leg during
cycling. This system is designed for training the upstroke
phase during cycling. The effects of training with Smart-
Cranks on the power output (PO) and on cycle work
distribution at the anaerobic threshold and the maximum
power level were examined. Twenty male, non-professional
cyclists were randomly assigned into intervention
and control group, training 5 weeks with SmartCranks and
conventional cranks, respectively. Before and after the
training period the subjects performed an incremental test
to exhaustion. Lactate was measured to determine the
individual anaerobic threshold (IAT) and forces at the
pedal were recorded to quantify changes in the work distribution
over the full revolution. We observed no
significant statistical difference for peak power (PO;
333.3 ± 32.8 W vs. 323.3 ± 21.8 W) and PO at IAT
(229.6 ± 30.1 W vs. 222.7 ± 25.2 W) for SmartCrank
and control conditions, respectively (P[0.05). However,
we did observe that work distribution in the downward
phase was significantly reduced in the SmartCranks training
group at peak PO (from 70.0 ± 4.9% to 64.3 ± 5.8%;
P\0.05). Although the possible implications of the
change in the work distribution of sectors are not known,
for the success in cycling performance—indicated by the
PO—training with the SmartCranks was not more advantageous
than training with conventional bicycle cranks.

 

[FrankDay]

As Hugh pointed out would have to show the muscle was working maximally. A flying 200m is ridden at only 90-95%% of maximal power. A road time trial at 15-25% of maximal power. So your assumption of a muscle working maximally is incorrect.

You don't quite understand the concept of a thought experiment do you?

Anyhow, I challenge anyone to come here an present a cogent argument that training the most used (relatively compared to their capability) muscle of a group to be used even more is a more efficient way to train than to train the least used muscle (relatively) of a group when each has the potential to cause the same amount of improvement (remember, 5 lbs here is the same as 5 lbs there). Or, that if all the muscles are working equally (relatively), that it is better to only train half of the muscles to get better (and making the use of the muscles unequal) instead of trying to improve all of the muscles equally to get better for the same improvement. Especially remembering that the closer to max that a muscle is working the more metabolically inefficient fast twitch fibers must be utilized.

I will wait patiently because I think I will have to wait a very long time.

 

[CoachFergie]

Though experiment = imagination = mental masturbation.

We don't train muscles we train movements. Using a training device that requires the greater recruitment of the hip flexors has never been shown to improve performance in cycling.

 

[FrankDay]

Though experiment = imagination = mental masturbation.

I guess you are right. I can't think of a single instance in all of world history where a thought experiment ever led to any insight or advance. LOL

We don't train muscles we train movements. Using a training device that requires the greater recruitment of the hip flexors has never been shown to improve performance in cycling.

Oh wait, I thought of one. (I'll be you know the one.) And, was it 50 years after the concept was published that the first experiment that supported the concept was successfully conducted. Hmmmm. I guess lack of evidence is not evidence of lacking. What a thought.

 

[CoachFergie]

I guess you are right. I can't think of a single instance in all of world history where a thought experiment ever led to any insight or advance. LOLOh wait, I thought of one. (I'll be you know the one.) And, was it 50 years after the concept was published that the first experiment that supported the concept was successfully conducted. Hmmmm. I guess lack of evidence is not evidence of lacking. What a thought.

Sure there are many, I was merely referring to how you appear to use the concept

 

[FrankDay]

Sure there are many, I was merely referring to how you appear to use the concept

Perhaps. But since I was responding to the thought experiment of Dr. Coggan I will wait patiently for him to come and defend his thoughts. Or, will he decide to try to quietly slip away as he tends to do when things are not going his way?