Nike’s Fastest Shoes May Give Runners an Even Bigger Advantage Than We Thought

Discusser wrote:

I'm not arguing that the Vaporfly gives an advantage in the marathon over any other current shoe, it definitely does and in general their data supports that. But to try to put a firm number to that based on their flawed data is B.S. Four to five percent, by the way, is about the difference between tempo pace and marathon pace. Are they trying to tell me I could keep up my 15k race pace for a full marathon just by strapping these on?

I'm not sure why people are fixating on the 4% number. If your complaint is that it's kind of meaningless to be comparing VFs to Hoka Bondis and that it would be more meaningful to compare the VFs only to other racing-focused shoes, I agree with you. But they showed their work, so if you want to exclude all the hobby jogger shoes, you can do that. Just look at the top end of the charts. I don't have a problem with them including extra data. Just ignore it and look at the data that you consider relevant. The relevant claim here is not, "See they really are 4% faster than everything else!!!" That's not what any reasonable person is saying here. So I think you can all stop punching that straw man now.

One way to end all this debate but I bet Nike won't bite. Have Kipchoge run 2 five miles tempos runs. One wearing Next and another wearing Next minus the plate. Have him wearing a HR monitor.

the source of this article is fake news propaganda outlet, which hopefully dies, very soon, along with the rest of american pravda, time, nbc, bbc, cnn, and now google inc, etc.

Why is the NYT so obsessed with this shoe? This is like their 10th article about this god damn shoe

This 100%. They seem to be measuring runners who did the same marathon from year to year that switched to the shoes for the second one. They built a model to try to factor in other reasons for improvement but they're writing an article like it's fact when they've found one contributing factor. It would be better to study elite athletes. Let's find someone who always runs 2:10-2:12. Are they suddenly running well under that in Vaporfly's? Amateur runners can improve pretty easily to some extent. Better nutrition, hydration, pacing, weather, all in race. Better training, better workouts, etc., in the build up. If you fix some of those things and PR by a few minutes but wore the shoes, what is the benefit of the shoes? We still don't really know. I think Tucker's 1:30ish estimate might be right. Kipchoge ran 2:04 with his insoles flapping out. With regular flats I think he's still the GOAT running 2:03 or just under.

I hope other companies get their shoes out & that they're all competitive with Nike. Nike exists to sell shoes. They're really good at marketing. They love articles like this that make people want to get the shoes even though we can't pinpoint what their real aid is. I think the hype has taken over and if they help maybe you get a minute back if you're super fast and a little more the longer you're out there. But that assumes you've run a good race, caught a good day, and nailed your fueling plan. There are too many variables in running. We need studies to address those things.

NERunner053 wrote:

This 100%. They seem to be measuring runners who did the same marathon from year to year that switched to the shoes for the second one. They built a model to try to factor in other reasons for improvement but they're writing an article like it's fact when they've found one contributing factor. It would be better to study elite athletes. Let's find someone who always runs 2:10-2:12. Are they suddenly running well under that in Vaporfly's? Amateur runners can improve pretty easily to some extent. Better nutrition, hydration, pacing, weather, all in race. Better training, better workouts, etc., in the build up. If you fix some of those things and PR by a few minutes but wore the shoes, what is the benefit of the shoes?

"Better nutrition, hydration, pacing, weather..." Really? The weather is the same for everybody in the race. If the year-over-year performance improvement was the result of the weather it would apply equally to all participants, not just those wearing VFs.

You really don't seem to understand how this type of analysis works. They don't just look at runners who switched to VFs. They look at runners who switched to other shoes as well. Then they compare the runners who switched to VFs with the runners who switched to other shoes. The weather affects both of those groups equally. As for the other factors like the idea that there's a correlation between people who train harder being more likely to run in VFs, they already thought of that. If you had bothered to read the whole thing, you would have seen that they already thought of all the obvious potential flaws that you forum posters think they're missing. They didn't just look at race results. They were well aware that there might be a correlation between people training harder and buying the VFs, so they looked at people's training history on Strava as well to see if they could find a correlation there that could explain the results they were seeing.

Thank you for being a voice of reason. It is hard for Let's Run where most opinions are based on data where n = 1.

Nyt wrote:

Why is the NYT so obsessed with this shoe? This is like their 10th article about this god damn shoe

Why not? It's the biggest story in running today.

The Streak results aren't that unusual if you don't restrict yourself to cherrypicking one New Balance flat. It runs between a half and 1% faster than the Adios, Boston and some of the more popular and fast shoes. This would be what 45-90 seconds max for a 2:30 marathoner? Some of the other options are better values considering their durability and other personal preferences people might have.

This study by the NYT does a good job at putting the advantage the Vaporfly's edge in the 2-3% range over the next-in-class speedy shoes. That's been backed in some independent studies as well, and I don't find the holes in the studies people have tried to point out particularly convincing.

No I think "Discusser" was on to something. The Adidas Adios was clearly superior to the Streak when the two were on the market.

Subway Surfers wrote:

No I think "Discusser" was on to something. The Adidas Adios was clearly superior to the Streak when the two were on the market.

How so? The Streak was a considerably lighter shoe that the Adios so I would have thought that it would have been a faster shoe. Jack Daniels did some studies on shoe weights and he showed that a heavier shoe does increase your oxygen uptake for a given pace when compared to a lighter shoe.

Concupiscurd wrote:

https://www.nytimes.com/interactive/2019/12/13/upshot/nike-vaporfly-next-percent-shoe-estimates.html?action=click&module=Editors%20Picks&pgtype=Homepage

Typical media of over sensationalizing a story line. The results are not that suprising or different than what was found previously. The biggest takeaway is that they found no difference between the 4% and Next %.

The model which used the most valid approach of measuring within person changes found that the Vaporfly is only 2-3% faster than shoes like the Asics DS Trainer, Saucony Triumph, Adidas Energy Boost, Asics Noosa, Altra Escalante, NB 860 and NB 1400. Is this surprising at all? Most of those shoes are not even racing shoes. The Vaporfly/Next% were only about 1.5% faster than the Adidas Adios.

The whole study and storyline are suspect because this is a NYTimes sponsored study being published by the NYTimes and was not peer-reviewed.

heyyo wrote:

Typical media of over sensationalizing a story line. The results are not that suprising or different than what was found previously. The biggest takeaway is that they found no difference between the 4% and Next %.

The model which used the most valid approach of measuring within person changes found that the Vaporfly is only 2-3% faster than shoes like the Asics DS Trainer, Saucony Triumph, Adidas Energy Boost, Asics Noosa, Altra Escalante, NB 860 and NB 1400. Is this surprising at all? Most of those shoes are not even racing shoes. The Vaporfly/Next% were only about 1.5% faster than the Adidas Adios.

The whole study and storyline are suspect because this is a NYTimes sponsored study being published by the NYTimes and was not peer-reviewed.

You're a full percent off on what the data says...3-4% on these non-racing shoes and 2-3%+ faster on the bulk of Adios and other racing shoes.

THOUGHTSLEADER wrote:

This study by the NYT does a good job at putting the advantage the Vaporfly's edge in the 2-3% range over the next-in-class speedy shoes. That's been backed in some independent studies as well, and I don't find the holes in the studies people have tried to point out particularly convincing.

They are simply commonly accepted flaws in any retrospective study. There is one major limitation of this study and any study like it. Athletes chose to upgrade to the VFrather than being randomly assigned to the VF, creating self-selection bias. This is a very common issue data analyses. It's expected that athletes who chose to spend $250 on a pair of shoes were also the most prepared on average. This doesn't mean that the results are garbage or should be ignored but the 2-3% edge represents an absolute upper bound.

If it were possible to either randomly assign VF to some athletes and not others or at a minimum control for fitness or better yet a change in fitness we'd see a lower benefit of VF.

On top of that there's no way to control for the placebo effect of the shoes. If were able to assign runners to VFs in a blind manner we'd except the 2-3% edge to fall further. By how much who knows but it would definitely decrease.

The VFs are undoubtedly a better shoe than what's out there. That said, the 5% edge that a casual reader my interpret from this article is absolutely exaggerated and the potentially misleading, and even on close expectation a conclusion of 2-3% edge is an overstatement of the VF benefit.

Not necessarily. While you are correct that people who are putting more effort into preparing for a race are more likely to spend $250 on shoes, there is also another group of people who are more likely to spend $250 on a pair of shoes while not necessarily training any harder--rich people who want the prestige of always having the perceived best. Now maybe the effect of try-hards buying the shoes and pushing the average up outweighs the opposite effect of rich, over-the-hillers buying the shoes and dragging the average down, but still, if you're going to be nitpicking the confidence level of someone else's numbers maybe you should be a little more cautious about confidently declaring you know for sure what numbers represent an "absolute upper bound."

This is less relevant than you think. First of all we aren't looking at the VFs compared to being barefoot. We're comparing VFs to other shoes. And not just that, they compared runners who switched to VFs to runners who switched to other shoes. If there is a significant placebo effect here (which shouldn't be assumed before it's demonstrated), it would also apply to at least some other shoes. E.g. the Nike Streak. Someone who switches from a pair of heavy trainers that they ran a marathon in last year to a pair of Streaks for their marathon this year would have the expectation of running faster in their new lighter-weight racing flats. So there should be a placebo effect for people switching to other racing-focused shoes besides just the VFs. Likewise those other shoes in the racing category would likely get some of that try-hard benefit from people who are training harder choosing to run in a perceived faster shoe. The VFs aren't the only racing-focused shoe in town that someone trying to run fast might choose to run in.

Now I already know what you'll say next, "But the VF has so much more hype that its placebo effect must be larger." Maybe. Again this shouldn't simply be assumed before it's demonstrated, but okay I'll go with that assumption. Even if the VFs placebo is larger than the placebo for other racing-focused shoes due to the extra hype, then it's still part of the benefit. It still works. It's still faster. It doesn't matter why you ran faster in the VFs if all you care about is that you ran faster. If the VF placebo is larger than the Streak placebo, then the VFs still deserve their higher asking price. Regardless of the mechanism, they still succeeded at their goal of being faster than other shoes.

If you're a competing shoe company, then figuring out how much of the mechanism is placebo versus something else would be relevant to you. But if you're just a runner, it doesn't matter why the shoe is faster. It only matters that it is faster. And claiming that benefits derived from placebo aren't real or something is just silly. It's still real speed regardless of where it came from.