The 4% is cheating and should be banned

it's most definitely an engineered leaf-spring

it is not a flat plate like you might find on spike shoes, etc.

here is an x-ray/mri of a vaporfly, you can clearly see the shape of the spring, sandwiched between the foam to cushion the impact and store/forward the energy from the landing for toe-off

https://i.imgur.com/VfRS4sM.gif

and this is just the first generation, imagine how much better with every year as they tune it - I don't think anyone would have a problem with this shoe if they simply removed the literal spring, in fact they make a model without it so it's possible but no-one uses it for good reason

Why so soft?

The people calling this mechanism "not a spring" need to go back to freshman physics. There's no argument whether or not there is potential stored in the restorative force (spring force) of the mechanism (plate). It 100% acts like a spring.

The question should be whether or not the entire sport goes in the direction that the shoe companies want it to, or if some governing body should regulate the amount of work a shoe should be able to do under some standardized load.

I don't compete anymore (and I can't even run right now because of an injury), so it really doesn't bother me if it goes that way.

zoomzoomzoom wrote:

what, you can't bounce your shoes six feet off the ground?

https://video.twimg.com/ext_tw_video/1007958930595565568/pu/vid/360x640/6Ohbn53rmY-O0p0Y.mp4

This should be their super bowl ad. Honestly makes me want a pair

Puma brought out a shoe in the 60's called the brush spike which was banned, it had 68 spikes on the plate and the IAAF considered it an advantage. Hence the reason there are now a limited number of spikes allowed. What is to stop Nike from simply creating deeper, more effective springs? If you look at the prototype shoes Kipchoge has been seen training in with a huge midsole that is no doubt on the way soon.

zoomzoomzoom wrote:

what, you can't bounce your shoes six feet off the ground?

https://video.twimg.com/ext_tw_video/1007958930595565568/pu/vid/360x640/6Ohbn53rmY-O0p0Y.mp4

Where's the control group?

it's a spring, ladies wrote:

The people calling this mechanism "not a spring" need to go back to freshman physics. There's no argument whether or not there is potential stored in the restorative force (spring force) of the mechanism (plate). It 100% acts like a spring.

The question should be whether or not the entire sport goes in the direction that the shoe companies want it to, or if some governing body should regulate the amount of work a shoe should be able to do under some standardized load.

I don't compete anymore (and I can't even run right now because of an injury), so it really doesn't bother me if it goes that way.

it's not a spring

If boost shoes worked, the world record for marathons would be about 1:58.

They are nothing but a scam for people who don't understand the mechanics of running. Any sort of "energy return" device has already spent itself by the end of footstrike when the toe is still on the ground and the body pushing itself upward from it. The heel is drawn upward by the inertia of the leg above it moving forward. None of this is affected in the slightest by a bouncy sole, other than adding instability and possibly prolonging footstrike.

If that doesn't convince you, take "boost" to its extreme, the pogo stick. The Guiness world record for the pogo stick mile is only 7:40. Why so slow? Because it spends so much time on the ground that if you went much faster, you'd pitch forward on your face before getting into the air again. Running is about gaining and preserving forward momentum, not about jumping. Faster running requires shorter footstrike duration and higher cadence, which due the gravitational constant means less vertical motion. Boost devices promise the precise opposite of that, but fortunately are unable to deliver greater vertical motion, limiting the damage.

It's not the foam, it's THE CARBON FIBRE PROSTHETIC LIMB that is hidden inside the shoe that works like Oscar Pistorious's legs except on a smaller scale.

Yes. The University of Colorado at Boulder locomotion lab tested it and yes it is 4% faster. They performed this study against the adios and the zoom streak 6. They also added weights on the shows to ensure it was the shoe not the lack of weight that was increasing the efficiency.

Nike's claim is that it is 4% more efficient. This does not necessarily mean 4% faster. They are careful not to define "effeciency" in their marketing. They also don't say what, exactly, is their baseline (unless I haven't been paying as much attention). My assumption, is that the compression and relaxation of the sole of the shoe is 4% more efficient (coefficient of restitution?).

Just did a quick read of a few articles, and I guess the claim is 4% improvement in running economy over "the best marathon racing shoes out there," and this indeed seems to come from greater energy return in the foam (87% vs, say, Boost 2 at 76%). Seems like the plate mostly helps improve toeoff. All that does not necessarily translate to 4% faster marathon performance (but definitely some amount faster).

If I run a marathon in the nimbus 19 at 3hrs. Then I’ll run the exact same race in a streak 6 at 2:57 due to the weight of the shoe.

If I run in a lighter shoe, I go faster. If my feet feel less beat up (cushioning) I go faster. If I think I’m going to go faster - I go faster.

Do you see this?

Huh? I already posted:-

Vaporfly Asterisk wrote:

I can't believe all these idiotic justifications I read on here - "well you know, this / that / whatever shoe has cushioning so I guess they should be banned too / my PR in them shouldn't count". Absolutely Bananas! We are talking about a device which literally has a SPRING mechanism in it!

It is essentially in a different category of transportation. The Morans arguments on here is analogous to someone going out on a motorbike, breaking a cycling course record, then justifying it by saying "well you know, it just another improvement, you might as well say that only records set on penny farthings should count".

Justifying Vaporflys is equally ridiculous.

Do you see this?

Just to reiterate though, I don't really care about other people using them for hobbyjogging PRs, doesn't effect me in the slightest so no big deal. It's just I'd never use then personally as I'd never have any means of knowing if my effort / training had yielded a PR or if was just as a result of being bounced along by the spring.

Just kinda want to establish the springs are not most peoples biggest problem with the guy

Do all of you dorks think the Zoom Fly should be banned in addition to the Vaporfly?

You’re all morans if you think the 4% is cheating. You clearly don’t understand how the shoe, or running shoes in general work. It’s not giving you extra energy, it’s just reducing the amount you lose through the cushioning in the shoe by making it more rigid yet still having soft foam so your body doesn’t take a ton of impact damage. It’s not the first shoe to have a carbon plate in it. Adidas did it back in the early 2000’s but no one cares about that. Look the science with an open mind instead of just thinking all Nike products are trash.

Sincerely,

Someone who chooses other shoes that fit better but doesn’t think those wear them are cheating.

This guy answered the Zoom Fly question right here:-

zoomzoomzoom wrote:

it's most definitely an engineered leaf-spring

it is not a flat plate like you might find on spike shoes, etc.

here is an x-ray/mri of a vaporfly, you can clearly see the shape of the spring, sandwiched between the foam to cushion the impact and store/forward the energy from the landing for toe-off

https://i.imgur.com/VfRS4sM.gif

and this is just the first generation, imagine how much better with every year as they tune it - I don't think anyone would have a problem with this shoe if they simply removed the literal spring, in fact they make a model without it so it's possible but no-one uses it for good reason

zoomzoomzoom wrote:

it's most definitely an engineered leaf-spring

it is not a flat plate like you might find on spike shoes, etc.

here is an x-ray/mri of a vaporfly, you can clearly see the shape of the spring, sandwiched between the foam to cushion the impact and store/forward the energy from the landing for toe-off

and this is just the first generation, imagine how much better with every year as they tune it - I don't think anyone would have a problem with this shoe if they simply removed the literal spring, in fact they make a model without it so it's possible but no-one uses it for good reason

Please explain how the leaf spring works regardless of if you are a heal striker or forefoot striker.

So you start this same thread every few weeks huh?

You're as bad as that loser Jamin.