Let's not forget that a lab published data on this showing showing a 4.16% less metabolic cost vs their own shoe and 4.01% vs the Adidas Boost shoe across multiple velocities.

https://link.springer.com/article/10.1007/s40279-017-0811-2

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Brian Stover USAT LII
Accelerate3 Coaching
Insta

And at the bottom of that article, some authors are directly employed by Nike. Doesn't automatically disqualify the findings, but for sure you'd take a huge grain of salt if a study published saying that Marlboro cigarettes were less toxic than e-vapes, but the study included 2 employees of Marlboro cigarettes AND was partly (in large) funded by Marlboro.

Funding
This study was supported by a contract from Nike, Inc. with the University of Colorado, Boulder.
Conflict of interest
Wouter Hoogkamer, Shalaya Kipp, and Jesse H. Frank have no conflicts of interest relevant to the content of this article. Emily M. Farina and Geng Luo are employees of Nike, Inc. Rodger Kram is a paid consultant to Nike, Inc.


Paper authors:

Wouter Hoogkamer

Shalaya Kipp

Jesse H. Frank

Emily M. Farina

Geng Luo

Rodger Kram

Nike is not creating a shortage to up the demand I'm pretty certain. Their brand recognition is well ahead of most if not all other running shoe brands so there would be no clear benefit. The main reason behind the shortage comes in the complexity and difficulties in producing these PBAX foams, such as the ZoomX in the 4% shoes. This is why they crated the ZoomFly because there are no such issues in producing the EVA Lunerlon foam found in those.

It's interesting to see them releasing the ZoomX foam in their Pegasus Turbo model. This may be the first commercially available shoe using Pbax on the market if it proves to be a mainstay on the shelves of running stores. Only time will tell! If anybody has the capitol to do it, it's Nike.

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"Train so you have no regrets @ the finish line"

Ah yes the let's take any research with company funding with a grain of salt response. Lame.

It's fine to be skeptical, in fact I read the paper the first time with a skeptical mind as I do with all research papers.

It's beyond ridiculous to come on here and say take it with a grain of salt then provide no reason(s) other than it's got some Nike funding and some of the researchers have Nike ties. The main authors have zero Nike ties. My bet is Nike doesn't provide the bulk of their yearly funding either.

Go through that article find all the flaws in their methods and analysis and let us know what they are. My bet is you come up with minimal design flaws if any.

Either the results are what they are or the researchers faked the data. If the results are faked then I suspect the 3 lead authors may lose their jobs and the University of CO may lose a lot of money in grants from companies who are funding research there, as companies do at many universities.

Why would Univ of Colorado put forth a paper for publishing if it was full of errors or let the study proceed if they found flaws in the design prior to allowing it to take place? They have review committees for these reasons.

Go ahead, read the study then come back and tell us how it was manipulated to get the results they got.

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Brian Stover USAT LII
Accelerate3 Coaching
Insta

I work in science so I am EXTREMELY aware of bias in science.

You are looking at it wayyyyy too simply if you simply assume one can look at a paper, find frank errors or clear points of bias and say "Aha! Got ya!"

Any scientist who can get grant funding, knows a million different ways to interpret and present data to ones advantage. I can literally, without cheating, show the opposite of my results in scientific experiments by phrasing things selectively, comparing sets selectively (like selectively choosing Nike vs other specific shoes, even if you've tested 100 other shoes that have outperformed Nikes, but just omitting that from your presented data), etc.

This is the exact reason why you are REQUIRED now to show and print your conflicts of interest in medical research, where lives can and will be at stake.

It's totally simpleminded to think that you can detect all/most bias just by looking at what they present. It's what they DON'T present that will be the problem.

Tobacco companies NEVER published data that showed that tobacco harmed people, for decade. Their presented data is rock solid, correctly interpreted, even in retrospect. Still wanna smoke?

There's actually quite a bit of high-quality peer reviewed research documenting this sort of bias, and this is why it's required to be declared up front. Again, it also doesn't automatically disqualify your research; I've seen quite a few top Nature science journals from Merck, etc., that were groundbreaking and legitimate, despite their conflicts of interest. But you have to take the automatic assumption firsthand that bias can and will be involved when there is an obvious biased source.

the main issue here is the marathon world record is still run with adidas shoes so quites seriously it cant really be 3 % faster.... ( thats a half pink )
I think what we can say is approx 1 sec per km faster in the marathon sometimes we see more improvement and sometimes less but we certainly do not see constant 3-4 % faster as the study shoes (which includes weights as well so it should be even a bit more)
i do agree the study seems to be well controlled etc but the incresase of speed would appear to be exacurated and maybe the 1 % in the new york article in speed difference is more real world.

Which Nike app? I can't find them on the Nike app itself to even see if anyone has them.

Go to the App Store and just search nike. It should be the first app that shows up. It will say Nike Inc.

Once there you customize to the sports/product groups you are most interested in.

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Dave Jewell
Free Run Speed

interesting data, thank you..

of course the 4% is compared to.. what ? the average shoe, how determined ?

I see the Hoka Bondi is way down at the bottom of their list, at about -2.5%
Didn't expect that..

The Asics DS Racer seems to be the best bet for an affordable race shoe. I have an ancient pair that has been my tri race shoe for nearly a decade..

I'm no scientist, but I wonder if there's an argument that the shoe's effects increase with distance. The improvement here is energy transfer which to me means less pounding on the legs and supporting joints. I know my legs felt a lot "fresher" at the end of my last half than they usually do. "Fresher" legs or lack of "pounding" probably don't add much if anything to a world class 5K or 10K runner, but for an amateur marathoner they could equate to minutes per mile over the last 10k. NYT data is mixed on my theory. No real difference between half and full marathon improvements, but the fastest runners (who presumably have huge mileage bases and respond best to running fatigue/stress) have less improvement.

Heh, herewego.

The 4% is a great shoe, no question. A few facts:

- The NYT study is so flawed you can't imagine. It disregards a host of things, including confounding variables - things like if you can afford a 4%, you've likely got the time, $$, and social motivation to train more, so PRs come with it. What idiot wants to buy a Ferrari and report back to their neighbors that they were 7th slowest around the Neurburgring? It's marketing, pure and simple.

- It's not 4% faster. It could be faster on a given person with a given usage profile, with weight savings, a certain stride, footstrike, and carriage. What % is up for grabs, and to someone's point earlier, it could even make you slower. It wasn't 4% for the Sub2 challenge (enter the counfounding variables argument).

- Production is limited as part of the gameplan - if NIKE wants to make more shoes, they can, fairly confident in that. When you have a category leader / halo product, you keep it scarce, and work to come over the top with another innovation, and let the halo shine down.. That's what's happening. Rupp 6% Anyone?

- The Beaverton campus is absolutely giddy about the Turbo Peg 35. Everything you want in a shoe, without the wait and expense for the 4%. If it's sold out it's because the campus bought the entire production run - couldn't get the 4% either. There will be more.

- If you're a NIKE wearer, get the NIKE app. It's legit in getting you access to limited stock, limited run, unique colorways. Also pretty good for finding the odd sizes (size 12, anyone?).

All for now.

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- I do all my own stunts

Interesting. I had not connected the CF components in the TT 7.0 to the Nike approach or to Dave. I have a pair of Zoot TT 7.0 (also Shoebacca!). I like 'em enough, but I would not say that they 'feel' the fastest of my shoes (that goes to a pair of Newton Energy shoes with an ancient pair of Saucony Kinvara shoes - model #1, but unlabeled since there was not a Kinvara 2 yet - about the same perceived 'speed feel'). It might be an interesting ST poll to ask which shoes 'feel' fastest. But I remember the challenges of a recent shoe poll...

I was just looking at the weights of the pegasus turbo and zoom fly and it seems the turbo is 10 grams lighter for a size 9? so, is that just down to the plate in the fly? pegasus turbo suitable as a racing shoe for those who can't get their hands on the vaporfly?

It’s different foam in the turbo, and yes it’s a suitable racing shoe.

What about all the mop and bop riders that own a P5X?

I thought the ad said 4% compared to a regular running shoe and just 1% compared to other racing shoes