Splitting Semantics wrote:
aoxomoxoa wrote:
Not only that, but the purpose of the VF is to increase running efficiency, not to give the runner a "speed boost."
What an absolutely absurd thing to write. Especially in the context of your self righteousness.
Talk about a lack of self awareness.
If your boss asked you to work more efficiently and you simply started working faster, do you think you would be doing what was asked of you?
Words matter, Cheech. It's how language and communication work.
My god, unbelievable! Even though I called out your seeming lack of self awareness, you wade straight back in with that stunning misplaced self righteousness once again without pause for thought.
If my boss asked me to run as far as I could for an hour in an old pair of lead divers boots, then asked me to the same thing in a pair of any running shoes (even Brooks say) what footwear would you describe as more efficient to that particular task? What footwear would cover more ground in that hour?
Now here's the little thing to help you along - speed = distance / time. Now try thinking really hard about that and what that means if you use more efficient footwear. I think what has happened is that your little brain has got itself all confused, it's got all messed up over the 4% efficiency does not equal 4% speed increase thing, to such an extent that you've got it fixed in your head that they aren't correlated at all. This is obviously complete dribble.
So the thing is, when you're making incorrect statements that's one thing but when you follow it up with unnecessary vitriol like "Words matter, Cheech. It's how language and communication work" you pass from just sounding like someone lacking in understanding to sounding like a complete and utter f"ckwit.
This thread is stupid anyway. They're "Vaporfly" not "Vapourfly"...
Murica
To continue the whole "too stupid to eat or reproduce on its own" line of argument:
Okay, go to a public park with a level bike path. Get up to jogging speed, say 7.5 miles/hour. Then stop moving altogether.
Result in shoes: You stop.
Result in rollerblades: You sail on down the path for 50 yards before slowing to a stop.
Everyone else recognizes the difference. Claiming wheels are like a carbon plate really is one of the stupidest comparisons we've seen on here.
Also, scientists who have taken apart the VFs have found that the carbon plate contributes almost nothing to the shoes' energy return. They're good for adding stability, much like the Mizuno wave plate. (Should we ban all the Japanese marathoners who race in Mizunos, too?) All the VFs are is a light-weight marathon shoe made from a better foam than any of the competition have. It's light, cushiony, and springy all at once. You might as well try to ban shoes for being too light or for using EVA.
Ok, at least you are literally discussing a level playing field now!
The comparison at the level I've stated isn't stupid, it's simply a fact - they are both mechanical aids which reduce the loss of energy to the system.
Of course they don't do that to the same degree, as I said earlier though the point of using rollerblades is as an evocative example. e.g. you said you roll on down the path for 50 yards in the rollerskates. Maybe you do, maybe only 5 yards in another poorer quality pair. Do you allow the pair that only gives you 5 yards? No, you don't allow either because either way you've added an element which gives an unfair advantage.
Yeah, you're going to move even less in spring loaded shoes but your logic is wrong, you don't instantly stop. Especially pausing the system at the point that the spring is compressed. View that closely, at that exact point, and you would see the forced continuation of motion. The effect is smaller but then the mechanical aid is working every single step, for both feet, over 26 miles. That is the difference between using hybrid footwear and a running shoe.
Vaporfly Asterisk wrote:
Ok, at least you are literally discussing a level playing field now!
The comparison at the level I've stated isn't stupid, it's simply a fact - they are both mechanical aids which reduce the loss of energy to the system.
Of course they don't do that to the same degree, as I said earlier though the point of using rollerblades is as an evocative example. e.g. you said you roll on down the path for 50 yards in the rollerskates. Maybe you do, maybe only 5 yards in another poorer quality pair. Do you allow the pair that only gives you 5 yards? No, you don't allow either because either way you've added an element which gives an unfair advantage.
Yeah, you're going to move even less in spring loaded shoes but your logic is wrong, you don't instantly stop. Especially pausing the system at the point that the spring is compressed. View that closely, at that exact point, and you would see the forced continuation of motion. The effect is smaller but then the mechanical aid is working every single step, for both feet, over 26 miles. That is the difference between using hybrid footwear and a running shoe.
As other posters suggest, these are not spring loaded shoes. Your insistence on this point is likely at the core of your obsession. For the open-minded on this forum, there are credible sources who have analyzed this shoe's technology to death, among them:
https://www.runnersworld.com/news/a26480398/how-nike-vaporfly-4-percent-work/And you might want to look up the meaning of the word "evocative".
They are literal springs. If you don't understand that then you don't belong in this conversation.
And there's no difference between EVA, Boost, ZoomX. and springs. They all store energy on impact through compression and then release it. That's it. If you're going to ban one, then ban them all and let the minimalist fanboys win.
Vaporfly Asterisk wrote:
They are literal springs. If you don't understand that then you don't belong in this conversation.
Again, not me - use your own handle! If you want to add to the conversation fine, do so but don't hide behind someone else. Again this can be IP verified to be another user...
... And now I see that the handle has set as a verified account. Pathetic! Sad show of losing an argument.
Puzzled wrote:
Vaporfly Asterisk wrote:
Ok, at least you are literally discussing a level playing field now!
The comparison at the level I've stated isn't stupid, it's simply a fact - they are both mechanical aids which reduce the loss of energy to the system.
Of course they don't do that to the same degree, as I said earlier though the point of using rollerblades is as an evocative example. e.g. you said you roll on down the path for 50 yards in the rollerskates. Maybe you do, maybe only 5 yards in another poorer quality pair. Do you allow the pair that only gives you 5 yards? No, you don't allow either because either way you've added an element which gives an unfair advantage.
Yeah, you're going to move even less in spring loaded shoes but your logic is wrong, you don't instantly stop. Especially pausing the system at the point that the spring is compressed. View that closely, at that exact point, and you would see the forced continuation of motion. The effect is smaller but then the mechanical aid is working every single step, for both feet, over 26 miles. That is the difference between using hybrid footwear and a running shoe.
As other posters suggest, these are not spring loaded shoes. Your insistence on this point is likely at the core of your obsession. For the open-minded on this forum, there are credible sources who have analyzed this shoe's technology to death, among them:
https://www.runnersworld.com/news/a26480398/how-nike-vaporfly-4-percent-work/And you might want to look up the meaning of the word "evocative".
You may wish to google "letsrun Vaporfly Asterisk" to see these articles being discussed previously, as they have been ad nauseam. The major problem is the very first source that one references is the study were they didn't even separate the plate from the rest of the sole but made completely arbitrary decisions on what element caused what energy returns.
As for the "stability" being provided and "ankle support" again here is an image of the actual plate:-
https://3.bp.blogspot.com/-XilqWeqQ3m0/XA7D8g5aeCI/AAAAAAAABE4/lQw-DoFLMaE70nzISDqR_JoX0M7me0bDgCEwYBhgL/s1600/13.pngYou see width and flatness of the heel section? Please let me know exactly how that would provide ANY stability thanks...
This image shows the plate clearly for what it is, i.e. a lever (a form of spring for the uninitiated who again seem to be struggling on this thread with the possibility that springs can exist which aren't coil springs!).
And I'm absolutely happy with my use of evocative thank you very much. The fact that people can be so angered by comparison with rollerblades as an aid that they would steal my handle is more than enough to show how strongly feelings have been stirred.
Breaking my own rule here... I will concede that a plate could act as a form of a cantilever spring and if it could be demonstrated that it acts as an external mechanical device that provides an unfair advantage, then it should be banned in sanctioned competitions. But I am not yet buying the argument that the energy return is from this plate in the form of a spring as some posters are suggesting. A picture of the plate separated from the sole does not show how it bends and "springs back" during a stride - which is apparently the assertion. Instead of a picture of a static plate, what should be doing is heeding the work of physiologists and biomechanics experts who have conducted controlled testing and published peer-reviewed studies. And those studies are inclusive but they do not support the assertion that the carbon fibre plate acts as a spring. I have a lot of respect for Alex Hutchison, devoured his book Endure and even briefly chatted with him around the time he wrote this article: https://www.outsideonline.com/2367961/how-do-nikes-vaporfly-4-shoes-actually-work . This is an educated man whose life has recently been mostly devoted to the science of running and even he is unsure of why the Vaporflys work. Here's the part of Alex's article where he summarizes the published study that I have not gotten my hands on:
The results were somewhat unexpected. The bending of the carbon fiber plate stored and returned energy at a rate of 0.007 watts per kilogram with each stride. In comparison, the squashing and unsquashing of the thick ZoomX foam returned 0.318 W/kg—more than twice as much as either of the other shoes, and about 45 times more than the plate. So the shoe definitely functions like a spring, but in this analysis it’s the foam midsole rather than the stiff plate that makes almost all the difference in the shoe’s contribution to energy savings.
As for the other theories, running in the Vaporfly did indeed seem to save some energy that would otherwise be lost to toe-bending. But the magnitude of the savings was small enough that Hoogkamer and his colleagues don’t think it makes a major contribution to the 4 percent boost in running economy.
Instead, there seem to be more significant energy savings at the ankle joint—but not quite in the way they expected based on the “gear ratio” theory. The theory predicts that the Vaporfly will produce a larger rotational force at the ankle; the data, in contrast, showed a smaller rotational force. There are some long passages in the paper that explore why the result was the opposite of what they expected yet still produced an energy savings. I’ll summarize those passages loosely as follows: They’re not sure what’s going on.
So that’s where we stand for now. There are several other studies in the pipeline from Barnes and others that will give us further insights on how these shoes work. For now, we can say two things. One is that the shoes change how efficiently you’re able to lever force into the ground, in some way that’s not yet clear. The other is that the shoes act as a spring—but only in the way that virtually all shoes act as a spring, by having a soft midsole. Kram’s back-of-the-envelope guess that the foam midsole gives a 3 percent boost, and the carbon plate adds another 1 percent. But the math may not be that simple: there may be some synergy between the foam and plate that makes the whole greater than the sum of its parts.
The ideal test would be to try a Vaporfly with no carbon fiber plate and see what happens. Would it be like running on giant floppy marshmallows, or would it be just as good as the real thing? “We have wanted to test this for quite some time, but haven’t been able to get such prototypes,” Hoogkamer told me in an email. “I personally think that a big, thick ZoomX stack without a plate would be a lot less stable, specifically taking 90-degree turns at Kipchoge speed. I don’t think it will be too soft, but hard to say without testing it.”
As for other big question of whether they should be banned, the Colorado study makes an important point. It’s not enough to say “Shoes shouldn’t have springs in them, so we should ban springs,” because you have to define what you mean by springs. If it’s really the ZoomX foam that makes the biggest difference, then banning carbon plates will miss the mark. If it’s the angle and shape of the carbon plate that provides the magic, then setting an upper limit on midsole thickness or resilience will also miss the mark. To figure out what you need to ban, you have to have a clear idea of what it is that’s objectionable—beyond the mere fact that the shoes seem to work.
I agree, it's mostly the foam. If it's the plate, then why is no one raging on banning something like the Zoom Fly? Why isn't anyone getting 4% out of that shoe? It has the same carbon fiber plate. The difference is that it doesn't have Zoom X, so it's not as light and bouncy.
The results were somewhat unexpected. The bending of the carbon fiber plate stored and returned energy at a rate of 0.007 watts per kilogram with each stride. In comparison, the squashing and unsquashing of the thick ZoomX foam returned 0.318 W/kg—more than twice as much as either of the other shoes, and about 45 times more than the plate. So the shoe definitely functions like a spring, but in this analysis it’s the foam midsole rather than the stiff plate that makes almost all the difference in the shoe’s contribution to energy savings.
Understanding this (and this is from the study itself not Alex Hutchison's own interpretation) is absolutely key to understanding the flawed basis on which some people think it has been "proven" that the energy return comes from the magic zoomx foam.
They put the entire sole - including that plate, the picture of which we have above - into a machine which flattened the entire body and then the attributed the entire energy return in that "unsquashing" to the foam. i.e. they put the entire sole INCLUDING that shaped carbon fiber lever in it (! no kidding - read the study) into a machine and when they found that bounced back with a strong force (again look at the picture and think about it...) they said that was the foam!
Should Z-Coils be banned from races too?? Lmao
my 2c wrote:
Objections to the VF are stupid. Every shoe with foam soles provide some degree of cushion and some degree of energy return at the cost of a certain amount of weight. The materials used in the VF are incrementally better at doing what every other shoe out there is trying to do. There's no magic to them, no extra source of energy. Supplementing foam with mechanical additions of various kinds has been tried for years by Mizuno, Newton, On, and probably others. Now Nike is doing it, only they're doing it better than their competitors. It's capitalism and competition and technological innovation at its finest, and I am going to buy a pair.
+1 very fine post
Splitting Semantics wrote:
Now here's the little thing to help you along - speed = distance / time. Now try thinking really hard about that and what that means if you use more efficient footwear. I think what has happened is that your little brain has got itself all confused, it's got all messed up over the 4% efficiency does not equal 4% speed increase thing, to such an extent that you've got it fixed in your head that they aren't correlated at all. This is obviously complete dribble.
You are 100% incorrect on this, although you seem like too much of a douche canoe to actually admit it.
Speed has absolutely nothing to do with efficiency in running. Someone can be fast as hell, but have completely inefficient running technique.
Efficiency is how “efficient” (see that: the clue is in the title) your body utilizes energy to run. That can be slow running. That can be fast running. Someone can have a marathon PR of 3:27 and be a more efficient runner that someone who has a 2:28 PR.
Efficiency does not equal speed. It can lead to more speed (I.e., the energy savings can be transferred to effort instead of endurance), but they are not the same thing.
Use a dictionary if you’re having trouble understanding this.
I think even most low IQ folk, can figure if you are more efficient, that will go towards more speed given the context we are discussion (assuming same distance). You two need to stop arguing :)
Vaporfly Asterisk R1 wrote:
The results were somewhat unexpected. The bending of the carbon fiber plate stored and returned energy at a rate of 0.007 watts per kilogram with each stride. In comparison, the squashing and unsquashing of the thick ZoomX foam returned 0.318 W/kg—more than twice as much as either of the other shoes, and about 45 times more than the plate. So the shoe definitely functions like a spring, but in this analysis it’s the foam midsole rather than the stiff plate that makes almost all the difference in the shoe’s contribution to energy savings.
Understanding this (and this is from the study itself not Alex Hutchison's own interpretation) is absolutely key to understanding the flawed basis on which some people think it has been "proven" that the energy return comes from the magic zoomx foam.
They put the entire sole - including that plate, the picture of which we have above - into a machine which flattened the entire body and then the attributed the entire energy return in that "unsquashing" to the foam. i.e. they put the entire sole INCLUDING that shaped carbon fiber lever in it (! no kidding - read the study) into a machine and when they found that bounced back with a strong force (again look at the picture and think about it...) they said that was the foam!
I am saying the following with a huge amount of respect (as, by and large, your posts have been respectful and you deserve to be responded to in kind).
If, by "read the study", you mean
https://link.springer.com/article/10.1007/s40279-017-0811-2Yes, I read it and I cannot criticize their methodology. They are at least using a scientific approach and are experts in human kinetics and in the requirements of conducting such a study using sound methods. And they concluded the following:
For now, the elastic properties of the NP (Vaporfly 4%) shoes provide the best explanation for the metabolic energy savings. Our mechanical testing quantified that the NP shoes returned 7.46 J of mechanical energy per step versus 3.38 and 3.56 J for the NS (Nike Zoom Streak) and AB (Adidas Adizero Boost) shoes, respectively. The greater mechanical energy return in the NP shoes is mainly due to its substantially greater compliance rather than the greater percent resilience.
The bolding is mine - they concluded that the bulk of the energy return advantages of the Vaporfly were in the foam, not the plate.
As for their methodology, Hutchison's article describes part of it in this way:
Each runner had 44 reflective markers taped to their body and shoes for three-dimensional analysis of their running motion; they ran on a special treadmill that measured the forces as their feet hit the ground. This enabled them to calculate the angles, forces, and work done for each joint.
The properties of the shoe were also measured separately by a “rotational axis material testing machine” that bent the shoe lengthwise while simulating a running motion to estimate its bending stiffness. By combining the stiffness of the shoe with the forces hitting the treadmill and the relative movement of the reflective markers, the researchers could estimate exactly how much the shoe (and the stiff plate inside) compressed and bent—and, consequently, how much energy was stored and returned with each stride by different components of the shoe.
That is referred to in the study itself:
To properly execute a force-constrained mechanical test, the compression force and regional distribution of force needs to resemble that of human running. To implement this, we mounted a rigid foot-form (shoe last) to a material testing machine (Instron 8800 Series Servohydraulic System, Norwood, MA, USA) and snugly fit the foot-form into the fully constructed shoes (Fig. 2). The material testing machine compressed the midsole in the vertical direction by matching a general time history of the vertical ground reaction force measured during running. The force profile had a peak magnitude of ~ 2000 N and a contact time of ~ 185 ms, which is similar to the loading that we measured for our subjects at 18 km/h (Table 2). The foot-form shape and its material testing machine attachment location produced insole pressure patterns and magnitudes similar to those recorded during running. We calculated the amount of mechanical energy stored and returned for each shoe condition from the area under the rising (storage) and falling (return) portions of the force-deformation curves.
In my opinion, that's a signficant amount of effort to test a running shoe but it's clear that the authors wanted to ensure that any mechanical testing/measurement was useful in relating to real world running kinetics and they wanted their study to be scientifically sound. Kudos to them. I would never characterize all that effort and tremendously thorough lab approach for a running shoe in a critical way. But then again, I'm not a kinesiologist.
I am sure there is a way to conduct a study using different methodology that is better designed to prove or disprove the hypothesis that the carbon fibre plate isn't solely to stabilize/stiffen the sole but rather to act as a mechanical device to propel the runner's foot. In the meantime, I think that this study (and a few others) comes awfully close to not leaving much doubt that the plate does not act much as a mechanical device. Until the next study comes along, I will remain open-minded.
At this point, though, based on what I have read, what I have felt in my own running experience, and what I have seen in my own running data I do not see that the plate acts as a mechanical device. Roller blades are not analagous (I am just teasing a bit here - I know you didn't mean to suggest that they were).
But what if Nike (or somebody else) develops an even better foam that doesn't require a stiffening plate? Should a shoe with that foam be banned? The day when that question has to be answered will undoubtedly be upon us within just a few years. And it will be - as this thread poses - a valid question.
Right now, though, I am anti-ban.
Ottawa Runner wrote:
Vaporfly Asterisk R1 wrote:
Understanding this (and this is from the study itself not Alex Hutchison's own interpretation) is absolutely key to understanding the flawed basis on which some people think it has been "proven" that the energy return comes from the magic zoomx foam.
They put the entire sole - including that plate, the picture of which we have above - into a machine which flattened the entire body and then the attributed the entire energy return in that "unsquashing" to the foam. i.e. they put the entire sole INCLUDING that shaped carbon fiber lever in it (! no kidding - read the study) into a machine and when they found that bounced back with a strong force (again look at the picture and think about it...) they said that was the foam!
I am saying the following with a huge amount of respect (as, by and large, your posts have been respectful and you deserve to be responded to in kind).
If, by "read the study", you mean
https://link.springer.com/article/10.1007/s40279-017-0811-2Yes, I read it and I cannot criticize their methodology. They are at least using a scientific approach and are experts in human kinetics and in the requirements of conducting such a study using sound methods. And they concluded the following:
For now, the elastic properties of the NP (Vaporfly 4%) shoes provide the best explanation for the metabolic energy savings. Our mechanical testing quantified that the NP shoes returned 7.46 J of mechanical energy per step versus 3.38 and 3.56 J for the NS (Nike Zoom Streak) and AB (Adidas Adizero Boost) shoes, respectively. The greater mechanical energy return in the NP shoes is mainly due to its substantially greater compliance rather than the greater percent resilience.
The bolding is mine - they concluded that the bulk of the energy return advantages of the Vaporfly were in the foam, not the plate.
As for their methodology, Hutchison's article describes part of it in this way:
Each runner had 44 reflective markers taped to their body and shoes for three-dimensional analysis of their running motion; they ran on a special treadmill that measured the forces as their feet hit the ground. This enabled them to calculate the angles, forces, and work done for each joint.
The properties of the shoe were also measured separately by a “rotational axis material testing machine” that bent the shoe lengthwise while simulating a running motion to estimate its bending stiffness. By combining the stiffness of the shoe with the forces hitting the treadmill and the relative movement of the reflective markers, the researchers could estimate exactly how much the shoe (and the stiff plate inside) compressed and bent—and, consequently, how much energy was stored and returned with each stride by different components of the shoe.
That is referred to in the study itself:
To properly execute a force-constrained mechanical test, the compression force and regional distribution of force needs to resemble that of human running. To implement this, we mounted a rigid foot-form (shoe last) to a material testing machine (Instron 8800 Series Servohydraulic System, Norwood, MA, USA) and snugly fit the foot-form into the fully constructed shoes (Fig. 2). The material testing machine compressed the midsole in the vertical direction by matching a general time history of the vertical ground reaction force measured during running. The force profile had a peak magnitude of ~ 2000 N and a contact time of ~ 185 ms, which is similar to the loading that we measured for our subjects at 18 km/h (Table 2). The foot-form shape and its material testing machine attachment location produced insole pressure patterns and magnitudes similar to those recorded during running. We calculated the amount of mechanical energy stored and returned for each shoe condition from the area under the rising (storage) and falling (return) portions of the force-deformation curves.
In my opinion, that's a signficant amount of effort to test a running shoe but it's clear that the authors wanted to ensure that any mechanical testing/measurement was useful in relating to real world running kinetics and they wanted their study to be scientifically sound. Kudos to them. I would never characterize all that effort and tremendously thorough lab approach for a running shoe in a critical way. But then again, I'm not a kinesiologist.
I am sure there is a way to conduct a study using different methodology that is better designed to prove or disprove the hypothesis that the carbon fibre plate isn't solely to stabilize/stiffen the sole but rather to act as a mechanical device to propel the runner's foot. In the meantime, I think that this study (and a few others) comes awfully close to not leaving much doubt that the plate does not act much as a mechanical device. Until the next study comes along, I will remain open-minded.
At this point, though, based on what I have read, what I have felt in my own running experience, and what I have seen in my own running data I do not see that the plate acts as a mechanical device. Roller blades are not analagous (I am just teasing a bit here - I know you didn't mean to suggest that they were).
But what if Nike (or somebody else) develops an even better foam that doesn't require a stiffening plate? Should a shoe with that foam be banned? The day when that question has to be answered will undoubtedly be upon us within just a few years. And it will be - as this thread poses - a valid question.
Right now, though, I am anti-ban.
*Yawn*
You bore me.
Again not me.
What a total loser - nothing original to say on the subject and nothing original even in your trolling. Just the same thing again and again. Same lack of any intellect in your trolling as in your argument (or rather lack thereof). Pathetic ?
I’m a D2 female runner. Our coach explicitly told us not to visit LetsRun forums.
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