Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running

Nov 16, 17 7:26

Post #1 of 28 (5906 views)

Not sure if this had been released (in part) previously, but it seems as though a research group has just published some actual data into the efficacy of the Nike Zoom Vaporfly 4% shoes that were used in the Breaking-2 attempt. Certainly an interesting read and gives some insight into the 4% claim:

To summarise [my additions in red]:

- 18 high-caliber athletes ran six 5-min trials (three shoes × two replicates) in prototype shoes (NP) [seemingly an early Nike Zoom Vaporfly 4% prototype], and two established marathon shoes (NS [Nike Zoom Streak 6] and AB [adidas adizero Adios BOOST 2]) during three separate sessions: 14, 16, and 18 km/h [approx. 4:30, 3:45 and 3:30 min per km]. We measured submaximal oxygen uptake and carbon dioxide production during minutes 3–5 and averaged energetic cost (W/kg) for the two trials in each shoe model.

- Compared with the established racing shoes, the new shoes reduced the energetic cost of running in all 18 subjects tested. Averaged across all three velocities, the energetic cost for running in the NP shoes (16.45 ± 0.89 W/kg; mean ± SD) was 4.16 and 4.01% lower than in the NS and AB shoes, when shoe mass was matched (17.16 ± 0.92 and 17.14 ± 0.97 W/kg, respectively, both p < 0.001). The observed percent changes were independent of running velocity (14–18 km/h)

Last edited by: awenborn: Nov 16, 17 7:43

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [awenborn] [ In reply to ]

Nov 16, 17 7:46

Post #2 of 28 (5866 views)

Interesting. The slow pace is 7:15/mile and still was 4%. There was some speculation in the other thread that these shoes weren't that efficient, and in fact possibly a hindrance, if you were running slower than 7/mile.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [Sean H] [ In reply to ]

Nov 16, 17 8:03

Post #3 of 28 (5836 views)

IIRC those complaints centred around foot cramps, possibly due to the increased sole-stiffness? Worth noting that the test period here was only 5 mins long and would not have been influenced by issues like those. It seems as though you can still benefit from them at speeds that us mere mortals might run at, so long as your feet can take it.

It's annoying because I don't want to spend anywhere near that kind of money on shoes, but I'm sure someone I know will!

I seem to recall someone mentioning Rupp running in a similar shoe once, but I presume it didn't have the same sole-construction, because as discussed at length around the time of the Breaking-2 attempt, it would seem that they would be expressly forbidden under current IAAF regulations. I would presume the big shoe companies are lobbying them hard to relax the rules and allow shoes such as this in competition.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [awenborn] [ In reply to ]

Nov 16, 17 8:15

Post #4 of 28 (5802 views)

Rupp won Chicago and Shalane won NY in the 4%. The ones they used at the breaking 2 event were the "Elite" version that don't any rubber under the heel. I don't know how different they are other than the rubber missing from the heel for weight savings. They both have the carbon plate, but I don't know if it's the same plate.

Last edited by: Sean H: Nov 16, 17 8:17

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [Sean H] [ In reply to ]

Nov 16, 17 8:23

Post #5 of 28 (5772 views)

Interesting, well that shows how much I know about these things!

Looking at the rules, it seemed as though the carbon-plate was the main issue for potential IAAF non-compliance, but I guess if people are using them to win IAAF-sanctioned events then they must have been ruled as compliant.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [awenborn] [ In reply to ]

Nov 16, 17 9:09

Post #6 of 28 (5717 views)

I just looked at some specs of that Zoom Vaporfly. Looks crazy thick with Hokalike stack, but Nike managed to get the weight down to a scant 6.9oz, which is impressively low. Makes me wonder if these runners would go even faster with less stack/lighter shoe, but as is can't argue against their excellent race results with this shoe.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [Sean H] [ In reply to ]

Nov 16, 17 9:10

Post #7 of 28 (5713 views)

It is the same carbon plate in the Elite and 4%. The Zoomfly has the carbon infused nylon plate, which is different than the Elite & 4%.

The difference isnt just the rubber on the bottom. The entire shape, material, design, and placement is different on the Elite, as well as the upper. Same cushioning though (ZoomX) in the Elite & 4% while the Zoomfly has a form of Lunarlon.

The Elite has only been available for sale in limited quantities. 100 units available by raffle, for the opportunity to purchase, in both London and New York. We may see something similar in LA for the LA Marathon.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [Sean H] [ In reply to ]

Nov 16, 17 13:01

Post #8 of 28 (5566 views)

Out of curiosity, I looked at the Zoom Vaporfly 4% on Nike's site. They say the drop is 10mm?! This must be a shoe for heel-strikers only, unless I'm missing something. I anything over 5mm and my heel and ball hit at the same time, which throws my form all to hell.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [duckies] [ In reply to ]

Nov 16, 17 13:14

Post #9 of 28 (5544 views)

The Vaporfly actually almost forces you onto your toes. With a subtle forward lean, there is a sensation of being pushed, and turnover quickens.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [Mugen_EP] [ In reply to ]

Nov 16, 17 13:23

Post #10 of 28 (5525 views)

Do you know how the durability of the shoe is, then? I'd be willing to try it, but if I'm only getting 100 mi out of the shoe versus 250 then it's not a possibility.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [duckies] [ In reply to ]

Nov 16, 17 13:29

Post #11 of 28 (5515 views)

Depends how you strike but there are reports of shoes from people having 500 miles on the Vaporflys. Heel strikers seem to wear through them more quickly but they are still seeing 250+ miles out of them.

New pair vs 500 mile pair.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [Sean H] [ In reply to ]

Nov 17, 17 2:56

Post #12 of 28 (5345 views)

Well it seems like I'm not the only one who is somewhat confused by their legality despite being seemingly in violation of the IAAF rules:

https://twitter.com/...s/931469016643891200

I went back and found my post from the original Breaking-2 thread where I dug-up the IAAF rulebook and to copy it here:

IAAF Rulebook - Section 143 wrote:

Shoes
2. Athletes may compete barefoot or with footwear on one or both feet. the purpose of shoes for competition is to give protection and stability to the feet and a firm grip on the ground. Such shoes, however, must not be constructed so as to give an athlete any unfair additional assistance, including by the incorporation of any technology which will give the wearer any unfair advantage. A shoe strap over the instep is permitted. All types of competition shoes must be approved by IAAF.

...

Inserts and Additions to the Shoe
6. Athletes may not use any appliance, either inside or outside the shoe, which will have the effect of increasing the thickness of the sole above the permitted maximum, or which can give the wearer any advantage which he would not obtain from the type of shoe described in the previous paragraphs.

I appreciate that wording is vague (and probably deliberately so) but surely Nike have just proven that their shoes are non-IAAF compliant?!

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [awenborn] [ In reply to ]

Nov 17, 17 3:26

Post #13 of 28 (5333 views)

I remember reading that the carbon plate on the Elite was custom moulded, at least for the athletes involved in the Breaking2 initiative.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [awenborn] [ In reply to ]

Nov 17, 17 5:15

Post #14 of 28 (5278 views)

awenborn wrote:

I went back and found my post from the original Breaking-2 thread where I dug-up the IAAF rulebook and to copy it here:

IAAF Rulebook - Section 143 wrote:

Shoes
2. Athletes may compete barefoot or with footwear on one or both feet. the purpose of shoes for competition is to give protection and stability to the feet and a firm grip on the ground. Such shoes, however, must not be constructed so as to give an athlete any unfair additional assistance, including by the incorporation of any technology which will give the wearer any unfair advantage. A shoe strap over the instep is permitted. All types of competition shoes must be approved by IAAF.
...
Inserts and Additions to the Shoe
6. Athletes may not use any appliance, either inside or outside the shoe, which will have the effect of increasing the thickness of the sole above the permitted maximum, or which can give the wearer any advantage which he would not obtain from the type of shoe described in the previous paragraphs.

I appreciate that wording is vague (and probably deliberately so) but surely Nike have just proven that their shoes are non-IAAF compliant?!

Just to follow up on this, even though I'm seemingly the only one who cares... I was (very) bored over lunch, so I checked the latest IAAF Competition Rules and Regulations and it appears that the "incorporation of technology" clause on shoes (highlighted above) has been cut out since I quoted it last time. It still leaves the rule ridiculously vague (and again, probably intentionally so) but the change to the wording would perhaps give Nike enough wiggle room with the Vaporfly?

So, it would seems as though the IAAF are happy to allow them... the start of a quiet revolution in modern running shoe design?

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [awenborn] [ In reply to ]

Nov 17, 17 8:23

Post #15 of 28 (5165 views)

good review by Alex Hutchinson of the study,

https://www.outsideonline.com/...-marathon-shoe-claim

"The Vaporfly prototype they tested returned 87.0 percent of the energy, compared to just 65.5 percent from Nike’s previous state-of-the-art marathon racer, the Zoom Streak 6. Interestingly, they also tested the Adidas Adizero Adios Boost 2, which was used by Dennis Kimetto to set the current men’s marathon record of 2:02:57. It returned 75.9 percent of the input energy. The authors note that versions of these two shoes (the Streak 6 and the Boost 2) had been used for all ten of the fastest marathons in history at the time the study started, in April 2016."

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [duckies] [ In reply to ]

Nov 17, 17 12:28

Post #16 of 28 (5051 views)

Reading the reviews on Nike they seem to have bit of a problem with the durability.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [awenborn] [ In reply to ]

Nov 17, 17 13:35

Post #17 of 28 (5004 views)

When a pharmaceutical sales rep comes in my office and shows me his/her company's brochures indicating why their product is better than anyone else's, I get suspicious. This "study" was funded by Nike. Did you expect to see any other results? First thing to do before reading a scientific study is to consider the source.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [treyedr] [ In reply to ]

Nov 17, 17 13:43

Post #18 of 28 (4993 views)

Being a research scientist myself, I'm well aware of the concept of "conflict of interest"; I did check the declaration statements at the end of the paper before posting, hence my choice of words in this thread title: "Nike Publish Data..."

Having said that, please feel free to read the Outside Online article linked above for some background on the research groups involved and their reputations within the field.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [awenborn] [ In reply to ]

Nov 20, 17 5:11

Post #19 of 28 (4713 views)

Ran in a pair of Vaporfly 4% yesterday at a 10k race. Gotta say I think the research was spot on based on both the results I got and also how recovery is going after the race.
Recent background is I ran this race last year (not as trained) and ran a 38:48 and then had a 10K PR last December with a 37:38 ( 100 day run challenge in effect).

So this Sunday's race I ran 36:47 10K, a PR by 51 Seconds and 2 minutes faster than last years race. Super fun race with a stacked field ( 3 guys ran 29 minutes and a 45 age group world record was set).
These shoes definitely make you feel as if you are using less energy and helped me hold my pace throughout the race.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [dualsport] [ In reply to ]

Nov 20, 17 6:19

Post #20 of 28 (4659 views)

Nice! I am not so patiently awaiting the email from Nike that they're releasing more, and hoping that I can grab a pair quickly when they do.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [Sean H] [ In reply to ]

Nov 20, 17 8:06

Post #21 of 28 (4615 views)

Hard to believe they're not artificially keeping availability this low.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [Mugen_EP] [ In reply to ]

Nov 20, 17 8:09

Post #22 of 28 (4612 views)

Mugen_EP wrote:

The Vaporfly actually almost forces you onto your toes. With a subtle forward lean, there is a sensation of being pushed, and turnover quickens.

Similar to newtons??

_________________________________________________
When all is said and done. More is usually said than done
Ba Ba Booey

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [Turd Ferguson] [ In reply to ]

Nov 20, 17 8:21

Post #23 of 28 (4597 views)

Turd Ferguson wrote:

Mugen_EP wrote:

The Vaporfly actually almost forces you onto your toes. With a subtle forward lean, there is a sensation of being pushed, and turnover quickens.

Similar to newtons??

nah, similar to other high ramp shoes like Adidas Boost Adios but with a leaf spring, not a lug ;)

Eric Reid AeroFit | Instagram Portfolio
Aerodynamic Retul Bike Fitting

“You are experiencing the criminal coverup of a foreign backed fascist hostile takeover of a mafia shakedown of an authoritarian religious slow motion coup. Persuade people to vote for Democracy.”

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [Thorax] [ In reply to ]

Nov 20, 17 10:41

Post #24 of 28 (4528 views)

They definitely are

And a heads up for anyone looking to get a pair, looks like Nike is going to release more on Friday so be on the lookout. You may be able to preorder some at your local running store.

Re: Nike Publish Data to Back Up Efficacy of Vaporfly 4% Shoes in Reducing Energetic Cost of Running [doug in co] [ In reply to ]

dontswimdontrun

Nov 21, 17 15:32

Post #25 of 28 (4364 views)

doug in co wrote:

good review by Alex Hutchinson of the study,

https://www.outsideonline.com/...-marathon-shoe-claim

"The Vaporfly prototype they tested returned 87.0 percent of the energy, compared to just 65.5 percent from Nike’s previous state-of-the-art marathon racer, the Zoom Streak 6. Interestingly, they also tested the Adidas Adizero Adios Boost 2, which was used by Dennis Kimetto to set the current men’s marathon record of 2:02:57. It returned 75.9 percent of the input energy. The authors note that versions of these two shoes (the Streak 6 and the Boost 2) had been used for all ten of the fastest marathons in history at the time the study started, in April 2016."

But surely with twice the deformation, there is twice the energy input, and losing 13% of that is as bad as losing 24% of half the amount of stored energy? Maybe this is still more efficient than energy rebound within the muscle/tendon/skeletal system, but if a big spring is what is required for efficiency and therefore speed, why are racing shoes thinner than training versions?
Bit confused by the quoted numbers too - 14-18km/h requiring 40-60ml O2/kg/min seems right, but what is energetic cost of 14-20W/kg? These guys averaged 64kg, or is that 32kg/foot

Our Partners

transition-DOT-area-AT-slowtwitch-DOT-com

Advertise with us

©1999-2024 Slowtwitch, Inc., and Slowtwitch.com
Reproduction of material from any Slowtwitch.com page
without written permission is strictly prohibited.