Calf muscles - is it worth working on them?



bikeguy

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Fday said:
I didn't know that the efficiency of contracting the quads varied depending upon where the foot is on the pedal circle.

I'm not sure what you mean Fday, but I know that cycling by contracting my quads while on the upstroke and contracting my hamstrings on the downstroke would lead to much going nowhere very quickly. (Ok, maybe the glutes could get me to move forward).

My take on the attempt to tangentially direct the force using the quads. The problem is that you need to start the contraction earlier in the crank cycle (just as the foot comes over the top or before) to have any benefit (the torque of sideways leg force is maximized here). That benefit comes at a cost of having to have the quads active for a longer period of time (as WarrenG already said) if one wants to apply force during the rest of the downstroke. There's another drawback, in that the mechanical advantage of the quads (and hams and glutes) action is better when the leg is more extended. To me that means quad action should be reserved for the last half of the downstroke, not the first half.

I also know intuitively that leg and hip extension is enhanced by simultaneous action of all muscle groups. Having one fire here (quads), and another there (glutes) isn't the best way to develop power, slowly (road racing) or quickly (sprinting). That's for one half of the pedal cycle.


-Bikeguy
 

Fday

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bikeguy said:
I'm not sure what you mean Fday, but I know that cycling by contracting my quads while on the upstroke and contracting my hamstrings on the downstroke would lead to much going nowhere very quickly. (Ok, maybe the glutes could get me to move forward).

My take on the attempt to tangentially direct the force using the quads. The problem is that you need to start the contraction earlier in the crank cycle (just as the foot comes over the top or before) to have any benefit (the torque of sideways leg force is maximized here). That benefit comes at a cost of having to have the quads active for a longer period of time (as WarrenG already said) if one wants to apply force during the rest of the downstroke. There's another drawback, in that the mechanical advantage of the quads (and hams and glutes) action is better when the leg is more extended. To me that means quad action should be reserved for the last half of the downstroke, not the first half.

I also know intuitively that leg and hip extension is enhanced by simultaneous action of all muscle groups. Having one fire here (quads), and another there (glutes) isn't the best way to develop power, slowly (road racing) or quickly (sprinting). That's for one half of the pedal cycle.


-Bikeguy

What I meant was the muscle contraction efficiency itself is independent of leg position. Actually, it is not entirely so, as a muscle become less efficient if it is near end contraction or super stretched, but this doesn't occur in normal cycling unless one is in an extreme aero position, and then only for the hip flexors. But, the rest of what you said is in keeping with my thoughts. When the muscles contract have everything to do with overall cycling efficiency. You point out the big things, pushing down on the up stroke. What I was talking about is more nuanced.

And, trying to get the forces to be tangential does not require the muscles to fire any more than 50% of the circle. The quads will fire only when the knee is extending and the hamstrings when it is flexing. And the HF's are firing when the hip is flexing and the glutes when it is extending. The only difference is the magnitude of the firing must be modified to optimize the direction rather than just firing maximally. What this should mean in real life is one is working less hard for more benefit.

To change this pattern (at least somewhat) is not that hard to do if one gets enough of the proper feedback as evidenced by the fact that most new PC users have a difficult time just making the pedals go around the first time they use them and a week later they hardly have to think about it at all.

And, where do you get that the mechanical advantage of the quads is greater when the leg is extended? Even if it is, what is the advantage of extending them hard if the direction of the force on the pedals is perpendicular (or nearly so) to the pedal circle? On PowerCranks I can stand up with both legs down and put high force on the quads and glutes, locking the knee in extension and the cranks will go nowhere because all I am doing is standing on them putting my full body weight perpendicular to the pedal circle. How much energy expended gets to the wheel has a lot more to do than how hard you are working the muscles.

You, of course, are free to try to pedal however you think is best. I am telling you what I think is best (and why I think it is best) and I can tell you a lot of very good cyclists agree with me. At the same time, some very notable "authorities" disagree with me, some of them even post here. So, you will have to draw your own conclusions. Someday I will be proven either right or wrong. At that time those of you who disagree with me will also be proven either right or wrong. Until then we will have to agree to disagree.

Frank
 

bikeguy

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Fday said:
What I meant was the muscle contraction efficiency itself is independent of leg position. Actually, it is not entirely so, as a muscle become less efficient if it is near end contraction or super stretched, but this doesn't occur in normal cycling unless one is in an extreme aero position, and then only for the hip flexors.

The quads are pretty much at end of contraction when your foot is at the bottom. Depending how high you set your seat height. ;-)



Fday said:
And, trying to get the forces to be tangential does not require the muscles to fire any more than 50% of the circle. The quads will fire only when the knee is extending and the hamstrings when it is flexing.

Wrong. The hamstrings are active during hip extension. They both extend the hip and flex the lower leg.



Fday said:
And the HF's are firing when the hip is flexing and the glutes when it is extending. The only difference is the magnitude of the firing must be modified to optimize the direction rather than just firing maximally. What this should mean in real life is one is working less hard for more benefit.

You're still not considering the length of muscle activity and it's effect on muscle fatigue, and you've ignored the leverage principles by which the quads get more leverage during the 2nd half of the downstroke, not the first. Another problem is that by pushing out at the top of the downstroke, you're going to be generating a downward force that doesn't develop much torque in the direction of crank motion.
Fday said:
To change this pattern (at least somewhat) is not that hard to do if one gets enough of the proper feedback as evidenced by the fact that most new PC users have a difficult time just making the pedals go around the first time they use them and a week later they hardly have to think about it at all.
I fail to see the connection between how difficult it is to turn the PC's and any possible effect on pedalling efficiency.

Fday said:
And, where do you get that the mechanical advantage of the quads is greater when the leg is extended?

Forcewise? Ever done a partial deadlift or back squat?

As to power generation I'm not actually sure why, but a vertical jump started from a half squat position will go higher than from a full squat. Probably has something to do with optimal muscle length and power generation, and leverage.
Fday said:
Even if it is, what is the advantage of extending them hard if the direction of the force on the pedals is perpendicular (or nearly so) to the pedal circle?

It isn't. Which way does the pedal move when it's in the forward position and perpendicular to the ground? Which way does the foot move when you extend the knee in that position?


Fday said:
On PowerCranks I can stand up with both legs down and put high force on the quads and glutes, locking the knee in extension and the cranks will go nowhere because all I am doing is standing on them putting my full body weight perpendicular to the pedal circle. How much energy expended gets to the wheel has a lot more to do than how hard you are working the muscles.
[/QUOTE
On a regular road bike with no powercranks, I can also put all my weight on a pedal and not have the bike go anywhere! However, I'm not going to attempt to link that with cycling efficiency. Trackstanding is fun.
Fday said:
You, of course, are free to try to pedal however you think is best.
Yes, I will.
Fday said:
I am telling you what I think is best (and why I think it is best) and I can tell you a lot of very good cyclists agree with me. At the same time, some very notable "authorities" disagree with me, some of them even post here. So, you will have to draw your own conclusions.

You haven't given any good evidence why PC's are better than just plain old cycling in terms of improving cycling efficiency. You've also shown that your knowledge of biomechanics is quite lacking (not that I'm an expert) which is disturbing considering your product is designed to improve athletic performance.

-Bikeguy
 

Fday

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bikeguy said:
The quads are pretty much at end of contraction when your foot is at the bottom. Depending how high you set your seat height. ;-)

At the bottom of the storke the hamstrings should be contracting, not the quads because the foot is moving backwards. The hamstrings should start before BDC for best efficiency.


bikeguy said:
Wrong. The hamstrings are active during hip extension. They both extend the hip and flex the lower leg.


Wrong, while it is possible the hamstrings can extend the hip, that is not their primary function. if the quads are contracting the hamstrings should be relaxed or you will be doing a form of isometric exercise contracting the agonist and antagonist muscles at the same time. Not veryefficient. In addition, if the hamstrings are contracting during hip extension to any extent and during knee flexion, that means they will be contracting during about 90% of the stroke. When are they supposed to recover?


bikeguy said:
You're still not considering the length of muscle activity and it's effect on muscle fatigue, and you've ignored the leverage principles by which the quads get more leverage during the 2nd half of the downstroke, not the first. Another problem is that by pushing out at the top of the downstroke, you're going to be generating a downward force that doesn't develop much torque in the direction of crank motion.

Of course I am considering that. That is a different concept. One must stay within the endurance ability of all of the muscles they are using or they will bonk. Regarding the leverage advantage of the muscles in the different positions we will just have to agree to disagree that this is a significant factor.

bikeguy said:
I fail to see the connection between how difficult it is to turn the PC's and any possible effect on pedalling efficiency.

Perhaps that is because you have never tried them. Or not. If you question the effect of PC's on pedaling efficiency I invite you to read the Luttrell paper.


bikeguy said:
You haven't given any good evidence why PC's are better than just plain old cycling in terms of improving cycling efficiency. You've also shown that your knowledge of biomechanics is quite lacking (not that I'm an expert) which is disturbing considering your product is designed to improve athletic performance.

-Bikeguy

Yes, I have. Read the Luttrell study. And you haven't given any evidence they do not improve cycling efficiency. We will just have to agree to disagree.
 

AmpedCycle

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Bahhhhhhhhhhh This post is still going on! It can't keep regurgitating itself forever... it just can't! Pretty soon it will have transformed into a hideous monster that lives under a bridge and eats little kids!
 

Billsworld

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Most of the thinking on how much strength/force is required to ride and even sprint, is low.(standing starts not included) The thinking is so low that weight lifting is a waste for endurance cycling. I havnt heard Fday say that the goal is to create the same tension around the full circle, just more tension on dead spots. This doesnt seem all that crazy to me. As far as cadence above 160 on the track. I listened to Antion Quist on tape say he works to get to 45 secs at 200 rpm on rollers. I also heard Curt Harnets wr in the 200 was done at around 190. I think at some point in higher cadences there just isnt alot of tension in any part of the circle. Hey maybe I am just slow........on the bike:)
 

bikeguy

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Fday said:
At the bottom of the storke the hamstrings should be contracting, not the quads because the foot is moving backwards. The hamstrings should start before BDC for best efficiency.

You said the leg doesn't fully extend in cycling. It does, almost. Therefore the quads are extended. I never said anything about what should be contracting
at that point. However, since the hams will be active already before the upstroke there is no need to worry about them starting too late. ;-)




Fday said:
Wrong, while it is possible the hamstrings can extend the hip, that is not their primary function. if the quads are contracting the hamstrings should be relaxed or you will be doing a form of isometric exercise contracting the agonist and antagonist muscles at the same time. Not veryefficient.
Wrong. The hamstrings will extend the thigh while the quads simultaneously extend the lower leg. Yes, that's right the hamstrings and quads can be active at the same time, and no, they don't interfere with each other. The hamstrings are bi-articular. The hamstring action occurs towards the end of hip extension, i.e, when the leg is almost straight.
Fday said:
In addition, if the hamstrings are contracting during hip extension to any extent and during knee flexion, that means they will be contracting during about 90% of the stroke. When are they supposed to recover?
It doesn't take much force to move the leg up as compared to the push
down phase, that is if one is only unweighting. The hip flexor is stronger anyway. The hams recover during the up phase.


Fday said:
Of course I am considering that. That is a different concept.

What is it you're considering?

Fday said:
Perhaps that is because you have never tried them. Or not. If you question the effect of PC's on pedaling efficiency I invite you to read the Luttrell paper.

There's a lot of things I haven't tried. Just because something can be tried, doesn't mean it should be.

I don't need to read the Luttrell paper, because everything that can be done to improve the motion of pedalling the legs in a circle can be done by training on the bike.

Just out of curiousity though, do you have the link to the full text study?



Fday said:
And you haven't given any evidence they do not improve cycling efficiency.
I haven't given any evidence that eating rice crispies religiously at 8 am every day doesn't improve cycling performance. I leave it to the rice crispie eater to give some good evidence that it does.

Seriously, I've seen some posts where you claim an impossible 30%+ increase
in power for the same oxygen consumption. No way buddy.

-Bikeguy
 

Fday

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bikeguy said:
You said the leg doesn't fully extend in cycling. It does, almost.

I love it :)



bikeguy said:
Wrong. The hamstrings will extend the thigh while the quads simultaneously extend the lower leg. Yes, that's right the hamstrings and quads can be active at the same time, and no, they don't interfere with each other. The hamstrings are bi-articular. The hamstring action occurs towards the end of hip extension, i.e, when the leg is almost straight.

And, when does the hamstring "action" stop if one is unweighting on the backstroke?

bikeguy said:
The hip flexor is stronger anyway. The hams recover during the up phase.

Stronger than what? During what portion of the up phase is the knee flexing? How does the knee flex if the hamstring is recovering unless one is not unweighting and pushing it up?

bikeguy said:
Just out of curiousity though, do you have the link to the full text study?

Here is the abstract. You have to pay to get the full text.

http://nsca.allenpress.com/nscaonline/?request=get-abstract&doi=10.1519%2F1533-4287(2003)017%3C0785:EOSTUP%3E2.0.CO%3B2



bikeguy said:
Seriously, I've seen some posts where you claim an impossible 30%+ increase
in power for the same oxygen consumption. No way buddy.

-Bikeguy

Sorry, I just pass on what is reported to me. I have had one report of an improvement in speed from 20 mph to 25 mph in six months for a 12 mile time trial. That calculates to almost a doubling of power. That is even more outrageous isn't it? Am I supposed to change the data because you believe it is not possible? No one knows what is possible until they try.
 

bikeguy

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Fday said:
I love it :)
Good. I have absolutely no idea what you love (I suspect it's the sweet scent of crisp greenbacks), but good for you. Nothing wrong with making a bit of dough.




Fday said:
And, when does the hamstring "action" stop if one is unweighting on the backstroke?
Well, jeez man, your an expert on the matter so why are you asking me?


Fday said:
Stronger than what? During what portion of the up phase is the knee flexing? How does the knee flex if the hamstring is recovering unless one is not unweighting and pushing it up?
I don't know, what are your thoughts?


Fday said:
Here is the abstract. You have to pay to get the full text.

http://nsca.allenpress.com/nscaonline/?request=get-abstract&doi=10.1519%2F1533-4287(2003)017%3C0785:EOSTUP%3E2.0.CO%3B2
Pay, huh? No thanks. I did view the abstract already.


Fday said:
Sorry, I just pass on what is reported to me. I have had one report of an improvement in speed from 20 mph to 25 mph in six months for a 12 mile time trial. That calculates to almost a doubling of power. That is even more outrageous isn't it?

Outrageous?. No, not at all. Did he ride on aerobars the second time or have a 20 km/hr tailwind?
Fday said:
Am I supposed to change the data because you believe it is not possible? No one knows what is possible until they try.

Speaking of the data, how come the AT of the PC group wasn't raised during that Luttrell study?

Fday, why don't you demonstrate a cyclist achieving a higher 1hr power than 510 watts at less than 79 kg bodyweight and/or breaking the 1hr record by, aw heck, any amount at all. Since your cranks would take the average pro close to Indurain's 1 hr power, that shouldn't be too hard to do
at all.

-Bikeguy
 

WarrenG

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Pedal very slowly up a steep hill. During the downstroke, reach around and feel how relaxed your hamstrings are. Or during a leg press or squat.

Yes, we are trying to minimize opposing muscle contractions but hamstring and quads both fire hard during the downstroke.

Frank, I was wondering... When there is a study of PC's, I assume the subjects know, or have an idea what the PC's are intended to do, or at least what they might do. This creates a bias in that group because now they will be mentally focused on improving something to do with their pedaling motion.

Do you ever have a control (or second) group that, instead of using PC's, uses a variety of drills intended to accomplish the same types of improvements you hope to see with use of the PC's?

My feeling is that both of these groups could help at least some people. Does the second group accomplish the same, or similar improvements?
 

Fday

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bikeguy said:
Good. I have absolutely no idea what you love (I suspect it's the sweet scent of crisp greenbacks), but good for you. Nothing wrong with making a bit of dough.

Read your post carefully again. key word is "almost"


bikeguy said:
Outrageous?. No, not at all. Did he ride on aerobars the second time or have a 20 km/hr tailwind?

No, as far as I know he was in the same position and under similar conditions, it was a loop he rode after all. But, would it matter to anyone really if the effect of training on PC's allowed him to ride in a more aerodynamic position rather than gaining power? The next year he improved his speed on this loop to 27 mph. OK, another anecdote. A coach just recently told me that in 1 season he improved his threshold from 245 watts to 300 watts. No tailwind here.


bikeguy said:
Speaking of the data, how come the AT of the PC group wasn't raised during that Luttrell study?

Well, I suspect it was but they didn't look at that. The study was designed to study efficiency. The follow-up test was done at the same power as the pre test (69% of VO2 max, which had been measured) and they measured energy expenditure at those powers.

bikeguy said:
Fday, why don't you demonstrate a cyclist achieving a higher 1hr power than 510 watts at less than 79 kg bodyweight and/or breaking the 1hr record by, aw heck, any amount at all. Since your cranks would take the average pro close to Indurain's 1 hr power, that shouldn't be too hard to do
at all.

-Bikeguy

How is this. Sam Whittingham held the HPV speed record of 72 mph. Then, 1 year after starting training on PC's he improved his own record to over 80 mph using essentially the same bike and fairing as the year before. If we assume the aerodynamics are the same (the wind conditions had to be almost the same in order to qualify for a record and it was on the same course) that calculates to approximately 40% power improvement. I suspect someday it will happen with the other records also but I think part of the problem is the very elite riders are being paid to race almost every weekend and they cannot afford the time it takes on the PC's to make the full adaptation to see the big improvements. This is more likely to happen I think when someone starts younger the PC's and matures into an elite athlete on them.
 

Fday

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WarrenG said:
Pedal very slowly up a steep hill. During the downstroke, reach around and feel how relaxed your hamstrings are. Or during a leg press or squat.

Yes, we are trying to minimize opposing muscle contractions but hamstring and quads both fire hard during the downstroke.

Frank, I was wondering... When there is a study of PC's, I assume the subjects know, or have an idea what the PC's are intended to do, or at least what they might do. This creates a bias in that group because now they will be mentally focused on improving something to do with their pedaling motion.

Do you ever have a control (or second) group that, instead of using PC's, uses a variety of drills intended to accomplish the same types of improvements you hope to see with use of the PC's?

My feeling is that both of these groups could help at least some people. Does the second group accomplish the same, or similar improvements?

The proof of what the muscle is doing is EMG analysis during pedaling, not how your leg feels when you are pedaling. EMG analysis will show very little hamstring activity during knee extension me thinks.

I don't design these studies. If I were to do so I would have 4 groups. One just rides the bike, one who does single leg drills, etc., one that has massive gold cranks like PowerCranks but are fixed like regular cranks and the subject is told the weight of the cranks is designed to help them develop the lift and they are to concentrate on that when pedaling, and a PowerCranks group. One of the problems is the more complicated the study the more difficult it is to do and the more it costs. I think the initial studies were/are just designed to see if the PC's do anything, not to answer more esoteric questions. That is appropriate until the benefit is "proven".

In my opinion pedaling drills will help cyclists to improve. It is just their potential is less than with PC's for several reasons. When I put people on the cranks at expos it is quite obvious which riders have put effort into developing a good "spin" doing one legged drills, etc.. But, even the best of these rarely have more than 2-3 minute endurance at a cadence of 90 or so. We have put a few very good RAAM riders on them and they were able to ride them for 15-20 minutes at high cadence without stopping first time, yet these riders still saw potential benefit in them and started training on them.

But, also, I regard each of my customers as a study of one. I suspect most of my pros (and many amateurs) have done a lot to try to improve pedaling style before PC's. I presume all customers had chosen training regimens that they thought was optimum for them before PC's whether that meant drills or just riding a lot. Essentially no one sends them back under our 3 month money back guarantee so I take that to mean they think the product is helping them to improve, not that they like to give their money to me. That feeling is reinforced by the feedback we get from customers. You, of course, can interpret this to mean they are simply all stupid.

The majority of those who send them back (about 3 in 1000) seem to do so because they have trouble adapting and they feel the PC's "take the fun" out of riding for them. PC's aren't designed to be "fun", they are intended to help make the serious athlete better, much better. Most of them find going faster "fun" though and they come to fall in love with the product. First they swear at us, then they swear by us.
 

WarrenG

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Fday said:
The study was designed to study efficiency. The follow-up test was done at the same power as the pre test (69% of VO2 max, which had been measured) and they measured energy expenditure at those powers.

... I think part of the problem is the very elite riders are being paid to race almost every weekend and they cannot afford the time it takes on the PC's to make the full adaptation to see the big improvements. This is more likely to happen I think when someone starts younger the PC's and matures into an elite athlete on them.

I don't pay much attention to studies that measure "performance" using an intensity near what I'd use for an active recovery ride.

Don't those elite riders have all winter to try out new things?
 

n crowley

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Frank, from your own experience and estimation, at a cadence of 90+ what percentage of the chain drive power applied to the pedal at 3 o'c can your combined forces in the upper and lower dead spot areas apply to the pedals when in their 12/6 o'c position ?
 

Fday

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WarrenG said:
I don't pay much attention to studies that measure "performance" using an intensity near what I'd use for an active recovery ride.

Don't those elite riders have all winter to try out new things?

Sure, but even all winter is not enough time to get the new muscles up the the same speed as their other muscles in an elite rider. For instance, Steve Larsen got on the cranks in November after he won the NORBA championship and rode them exclusively for about 3 months. When racing season started again he had to drop back to 2x per week because he said he could not ride his recovery rides on them yet because they were not recovery for him yet. These cranks are not a quick fix but require a lot of work and a lot of time to see the big benefits.
 

Fday

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n crowley said:
Frank, from your own experience and estimation, at a cadence of 90+ what percentage of the chain drive power applied to the pedal at 3 o'c can your combined forces in the upper and lower dead spot areas apply to the pedals when in their 12/6 o'c position ?

I will give you my own spindscan data that comes off the Velotron, which more accurate than the Computrainer and in my experience tends to give somewhat higher numbers, probably because of the huge flywheel.

Spinscan measures the ratio of the average to peak torque around half the pedaling circle (the pushing half). If we assume a smooth transition like a sine curve, the average represents a number halfway between the max and the minimum. A spinscan number of 50 would mean that the average torque is half the peak which I would interpret to mean that zero force is being applied at the top and bottom. Most riders tend to have spinscan numbers between 65 and 75.

The ratio of the forces at the top/bottom compared to the maximum push/pull would represent minimum to maximum force ratios thusly:

50 - 0
65 - 30
75 - 50
80 - 60
85 - 70
90 - 80
95 - 90

When I ride a course my spinscan numbers tend to range between 80 and 95. I have been at over 300 watts and sustained spinscan numbers of 95 (at least for a little while) without looking at the screen to maximize this number, so it is possible to learn to ride this way unconsciously, even at high powers.

This is a gross simplification but I think it represents an idea of what people actually do and what is possible.
 

acoggan

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Fday said:
The proof of what the muscle is doing is EMG analysis during pedaling, not how your leg feels when you are pedaling. EMG analysis will show very little hamstring activity during knee extension me thinks.

If that's what you really think, then you're wrong: when pedaling, the hamstrings are active during both the downstroke and approximately the first half of the upstroke, resting only between the point at which the knee becomes fully bent and when it starts extending again. As bikeguy pointed out to you, this is because the hamstrings assist with hip extension as well as knee flexion. More correctly/completely (although still somewhat oversimplified), you can consider the cocontraction of the hamstrings along with the knee extensors to serve to reorient the forces generated by the latter.
 

acoggan

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Fday said:
When I ride a course my spinscan numbers tend to range between 80 and 95.

So what's your gross/net/delta efficiency, Frank? Unless it is also much higher than average, this would argue against the idea (myth, really) that markedly reorienting the forces generated during pedaling increases efficiency.

Fday said:
I have been at over 300 watts and sustained spinscan numbers of 95 (at least for a little while)

For how long? (Just curious.)

Fday said:
without looking at the screen to maximize this number, so it is possible to learn to ride this way unconsciously, even at high powers.

That's been known ever since Peter Cavanagh's biofeedback work with the 1984 Olympic team pursuit riders. However, it apparently didn't help their performance, and once they stopped training this way they all reverted to a more normal pedaling style. What does that tell us?
 

n crowley

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Fday said:
I will give you my own spindscan data that comes off the Velotron, which more accurate than the Computrainer and in my experience tends to give somewhat higher numbers, probably because of the huge flywheel.

Spinscan measures the ratio of the average to peak torque around half the pedaling circle (the pushing half). If we assume a smooth transition like a sine curve, the average represents a number halfway between the max and the minimum. A spinscan number of 50 would mean that the average torque is half the peak which I would interpret to mean that zero force is being applied at the top and bottom. Most riders tend to have spinscan numbers between 65 and 75.

The ratio of the forces at the top/bottom compared to the maximum push/pull would represent minimum to maximum force ratios thusly:

50 - 0
65 - 30
75 - 50
80 - 60
85 - 70
90 - 80
95 - 90

When I ride a course my spinscan numbers tend to range between 80 and 95. I have been at over 300 watts and sustained spinscan numbers of 95 (at least for a little while) without looking at the screen to maximize this number, so it is possible to learn to ride this way unconsciously, even at high powers.

This is a gross simplification but I think it represents an idea of what people actually do and what is possible.



I don't believe in the Spinscan idea, I was hoping for your own estimation from the feeling you get when using the technique. If a rider was using Powercranks for the first time and used his lowest gear, would he have the same difficulty ?
 

Fday

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acoggan said:
So what's your gross/net/delta efficiency, Frank? Unless it is also much higher than average, this would argue against the idea (myth, really) that markedly reorienting the forces generated during pedaling increases efficiency.

Of course, as I suspect you know, that is impossible to know with just this data. The question I was trying to answer was what are the typical ratios of forces across the top to the maximum on the downstroke.

acoggan said:
For how long? (Just curious.)

a few minutes.


acoggan said:
That's been known ever since Peter Cavanagh's biofeedback work with the 1984 Olympic team pursuit riders. However, it apparently didn't help their performance, and once they stopped training this way they all reverted to a more normal pedaling style. What does that tell us?

What that tells me is that one cannot stop training this way or one will revert back to the old "lazier" ways. It is so easy to do when one is riding regular cranks. The muscle between the ears is the toughest muscle to train. The brain will change much slower than the other muscles to change. Even if the muscles are trained, if the brain doesn't naturally use them, it isn't going to occur.