CO= hr x sv wrote:
MarathonMind wrote:Well then so is Ross Tucker 'cuz he agrees with me.
http://sportsscientists.com/2017/03/ban-nike-vaporfly-carbon-fiber-devices-future-performance-credibility/There are no "springs" in the shoe; and yes, Tucker's hubris and refusal to be infallible type attitude makes him a borderline retard.
It's a leaf spring.
Bad Wigins wrote:
MarathonMind wrote:The carbon fiber and foam behave just like springs- they return almost all of the compressive force applied to them. They are indeed springs, just not made of steel as one typically thinks of one.
so are asphalt and concrete, the difference is they bounce back up a lot quicker.
Try this simple experiment, land on your "spring-loaded" shoes and observe whether you bounce back into the air.
The result shows what use that has in running. The body accelerates at the forefoot point of contact on toe-off. The toe stays in contact with the ground while the body pushes itself forward in front of it. The shoe itself is not accelerating the toe forward, but even if it were, that forward acceleration would require the body to exert extra force to gain the same boost, otherwise only the toe would be affected.
While it is well known that you are a Moran you can probably understand that feet do bend. As the body weight transfers forward it naturally bends the spring in the shoe and adds more pop to that flexion. The point is that all of the loading of the spring is going to happen anyway with no extra effort or energy expenditure from the runner.
Shshhdnnd wrote:
What science demonstrates that running on springs would be beneficial? Basically the runner and his or her shoes is a closed energy loop. Without an external source of energy, shoes cannot create extra energy for the runner.
So if the spring returns more energy, it also requires the runner to produce more energy.
this is correct! There isn't a magical energy source to propel the runners - they have to put energy in to get energy back. And frankly that doesn't sound very beneficial to me.
Why just focus on the shoes, we need to turn our attention to track surfaces. They should be cinder or grass. No exception. Modern tracks provide distinct advantages and results in faster (aided) times. All times not run on a standard cinder or grass track should be scrubbed from the record books.
I used to own a pair of genuinely springy shoes. They were a popular toy in the 90's - essentially a trampoline attached to each foot. The certainly did not help me run any faster, but were good fun nonetheless so I am sure the sub-2 attempt runners will have a great time during their run.
These are similar to the pair I had:
Have you guys not seen those grasshopper leg attachments you can buy? A person with no hops at all could jump over a soccer net.
You are overlooking the free energy return provided by gravity. What POSE was postulating on but actually true in this case.
Willruns wrote:
It's not necessarily energy return as the big brands (mostly Adidas) claim, as much as it is reduced energy loss. The Boost doesn't "return" any energy, the runner just loses less energy.
I think there is a video on YouTube where an Adidas exec. talks about the science behind Boost.
I can appreciate that and believe that is a more sensible explanation of the shoe.
That said, who cares. We already have track spikes that do the same thing. We also moved away from dirt tracks for the same reason.
On that basis there is no reason to argue that the shoe is providing an unfair advantage, as it is simply a variation on existing shoe and surface tech already.
For those of you that think the "spring" provides and advantage because springs bounce, think of running on a trampoline. Sure you can bounce high on it, but you won't run faster.
Shoes Bad, MMMKAY wrote:
Let's just ban all shoes that have unfair cushioning in them. Barefoot only.
I'd say yes.
The IAAF banned Spira shoes
And they're looking into banning the very Nike shoes you mention.
So - no records in spring loaded shoes are not OK.
Shshhdnnd wrote:
What science demonstrates that running on springs would be beneficial? Basically the runner and his or her shoes is a closed energy loop. Without an external source of energy, shoes cannot create extra energy for the runner.
So if the spring returns more energy, it also requires the runner to produce more energy.
the same argument would apply to riding a bicycle. lower energy loss is beneficial.
Imagine smaller versions of Oscar Pistrus' blades inside a shoe. That's how it works.
How is improved technology in shoes different than improved technology in bicycles (aero etc.)?
3hr-marathoner wrote:
Shshhdnnd wrote:What science demonstrates that running on springs would be beneficial? Basically the runner and his or her shoes is a closed energy loop. Without an external source of energy, shoes cannot create extra energy for the runner.
So if the spring returns more energy, it also requires the runner to produce more energy.
the same argument would apply to riding a bicycle. lower energy loss is beneficial.
Sure, you could make that argument, but it would be absurd. Unless we ban all shoes, we are already accepting some assistance with running. That assistance has been in a generally accepted form since shoes have been invented. The nike shoe is just another shade of grey.
A bicycle is wholly different, as is a car, roller blades, etc. So yes, we can argue that once we allow anything but barefeet, we then must allow runners to drive F1 cars, but that would be silly, wouldn't it?
boinger wrote:
How is improved technology in shoes different than improved technology in bicycles (aero etc.)?
I don't think is very different. One thing I've always liked about running is that you can be as well equipped as the top professionals for relatively small money (~$100 - $200) versus thousands for sports like cycling or triathlon. It was be disappointing if suddenly people needed expensive and hard-to-get shoes to be competitive.
Still, I think the problem of high performance shoes is of a lesser order than PEDs. If they are an unfair advantage, they should be banned but even if that can't or won't be banned, Nike is ultimately going to want to sell these things to the masses and that means they will be made available. If my daughter needs to wear $300 spring shoes to compete, I can accept that in a way I can't accept her needing to take a cocktail of anabolic steroids, HGH and EPO.
not just the tesla with the huge timing board breaking wind drag 15 feet in front of them but the arrow formation of pacers around the runners
not that this attempt is eligible for any world record anyway but what are IAAF (and/or USATF) rules about windbreaking pace cars and pacers ? there has to be something or I suspect we would have already seen a bubble placed around the front elites at major marathons under the excuse of security or something else distracting
oh and don't forget the moped bringing them drinks and gels so they don't have to slow for tables or handoffs, trivial compared to the car but still seconds per 5K
Not creating energy, giving a higher efficiency. Muscles are only about 92% efficient in a load-unload loop, springs are practically 100%.
Uh -- I think spring loaded shoes are also not OK, at least in 2007 according to IAAF rules:
Rule 144.2, relates to the use of†technical aids†during competition.
This new rule prohibits:
...
(e) Use of any technical device that incorporates springs, wheels or any other element that provides the user with an advantage over another athlete not using such a device.
Don't know if this was triggered by Spiro shoes, or Oscar Pistorious "Cheetahs":
IAAF Press Release in 2007 introducing a rule change with immediate effect:
https://www.iaaf.org/news/news/iaaf-council-introduces-rule-regarding-techni
Whistleblower wrote:
I am a industry insider.
The foam itself cannot give you MORE energy than you put in. It the higher energy return of the foam the more you get back. It is a form of spring in pure engineering terms.
The Carbon fibre leaf type spring hidden inside the Nike shoes works similar to Pistorious's foot. I believe it works in a couple of ways, directional propulsive energy return, and by changing the human biomechanics. The propulsion was a word commonly used in early Nike PR that has since been removed due to the obvious negative connotations. Plenty of google evidence from
Nike spokespeople who mentioned the propulsive benefit then after the initial backlash changed their story. The carbon leaf spring potentially lengthens the stride similar to Pistorious at the end of a 400m once he got up to steady state speed. It also potentially minimises bending at the inefficient metatarsal joint transferring more load to the more efficient Achilles and valve artificially changing the biomechanics of the runner. These changes explain why there have been several Injuries in the shoes and complaints about sore legs.
However what everyone is missing is the drafting effect of the big füçk off TESLA with timing board that has been specifically told to stay 5m in front of the runners.
You can argue about the shoes but this whole thing is irrelevant unless they get rid of the pace car, and the jump in pace makers.
OR, Put an equal number of similarly qualified athletes in the race wearing other brands of marathon racing shoes. Watch them punch it out to get the best position behind the car.
Blades
Its widely accepted that blades are an advantage
They return energy back to the runners stride in a way that the natural foot and conventional materials can't so why not just slap some blades under the shoes you might look like a circus performer but who cares if every stride you can go two extra feet then you could before why not run under 2 hours
Why not break every record ever run!!!
I am old enough to recall the fuss over fiberglass pole vaulting poles.
Bamboo then metal then fiberglass. The records shot up in the air, and the event thrived. There were a few bumps, like when they took away Bob Seagren's poles in the 72 Olympics.
That said, I love the padding of modern shoes compared to what we ran in back in the 70's, basically a slab of rubber with nylon holding it to our foot, no midsole. We welcomed the improvements.
I would not stop people who want to try out anything new and see what happens, short of doping. Let's see what goes down.
Maybe springs work, maybe they don't. Anyone here use the Spira?