Oh the irony. What if it turns out the new $500 adidas shoe is just way better than Nike's?

So if NIke shoes were not available to all in 2016, anyone running in them would therefore be breaking the rules...and when you break the rules, you get penalized.

So why hasn't Rupp had to return his bronze medal from his 2016 illegal shoes race? Or put another way...why haven't the authorities who make these rules followed through with the necessary sanctions for the cheaters?

How much are you benefiting from adidas by making this result about their shoes and not that this was an obvious doping result

Assefa breaking the record is like rain on Pre-Fontaine day, it's like the Nike commissary having 10,000 forks when all you wanted was a knife. It's a black fly in Phil Knight's chardonnay. Who would have thought that it figures? RoJo, that's who!

Blud doesnt know sig figs

Historically, early innovators stick to their model and are surpassed by others willing to go to extremes or challenge the basic paradigm, so it's unsurprising this could be happening to Nike where a company is willing to charge $500 for an extremely ugly shoe. If they turn out to be more effective than Nike's shoes, they will be banned.

You clearly don't know what the word ironic means.

That's not irony. Irony would be if Nike invented super-shoes to make their runners 4% faster but they actually made their runners 4% slower. There is nothing at all ironic about one running shoe company developing a shoe that is better that a competitor's shoe. That is exactly what a running shoe company's goal is, to develop a better shoe than their competitor. This involves innovation and the current trends.

you know what the answer is...

No, there's no way to generalise about how much time is gained from improving running economy. It's too individual, it's why Nike never made any time-related claims when pushing the OG Vaporfly

Ah, the irony police. Not everything is irony, but some things actually are.

From Oxford, irony is:

a state of affairs or an event that seems deliberately contrary to what one expects and is often amusing as a result

This would be accurate, no? Nike makes shoe, hopes to break parity with regards to racing shoes and lock in a long-lasting competitive benefit as a result. Then Adidas beats Nike at its own game and they get the benefit. It hasn't happened yet, but if Adidas turns the tables and becomes the company known for supershoes, I would consider that irony.

There's an interesting parallel to what happened in 2008-9 in swimming with the supersuits. I read a lot of comparisons to that era when the Vaporflys first came out, but it wasn't fully a match. Now maybe it is.

What happened in swimming is that Speedo (the largest, most dominant swimwear company; equivalent to Nike) came out with the LZR and put all their top swimmers in it for the '08 games. Immediately, it was pandemonium. Records fell left and right, and swimmers sponsored by other companies tried to get exemptions wear the suit. A lot of those exemptions were actually approved, because the other swimwear companies knew they were beaten and didn't want a reputation as a place that would force their athletes to lose over sponsor obligations. So Speedo was on top of the world for a year.

Soon afterwards, however, the suits were taken to the extreme. Companies like Arena, Jaked, and Blue Seventy, some of whom were decidedly not big players in the elite swimsuit world, took Speedos ideas to the extreme and made full polyurethane suits that were halfway to wetsuits. And these suits, if anything, surpassed the LZR by more than the LZR surpassed the old suits. Despite being the year after the Olympics (usually a slow year), 2009 was utterly insane. At Worlds, you'd have things happen like the world record go down in one semi, go down again in the other one, and then both swimmers swim even faster in the final. Speedo was decidedly NOT part of this new revolution, and their swimmers started getting crushed by the trend that they started.

What happened next was predictable. FINA quickly banned these suits, including the LZR and all the improvements that came afterwards. The suit-makers were once again working for marginal improvements, along with branding, instead of F1-style optimization. And Speedo has returned to doing quite well.

It's interesting to note that many of the 2009 records have still not been beaten, even with the rapid rate of improvement typical of swimming. I'm convinced that eventually they will all fall, but even today several are not seen as under threat.

The comparison is interesting because if Adidas does end up having a game-changing shoe, then I could see history repeating itself. Nike gets mad they're no longer on top and wants to go back to the old game. Athletes and fans get sick of all the technology-aided records. And then they get banned, from the Vaporflys onwards. The difference between running and swimming is it's possible that these records never get broken. Maybe Kiptum switches to Adidas, runs a 1:59, and then within a year we're back to 2:03s. Maybe Assefa's time remains the only sub-2:14. And while times do trend down in running, a few minutes could take decades to drop, if not longer. The swimming community can't wait for the 2009 times to be off the record books. We're the same way with the known dopers' records from the 1980s. It's worth thinking about what it will be like if the same thing happens with some of most prestigious events in running and in a way where there's serious doubt about the records ever being broken again.

The Nike labs OG Vaporfly study claimed 4% improvement in running economy would yield 3.4% improvement in marathon performance at WR pace

The study linked above also came from Nike labs. A 1.1% improvement in running economy corresponded to only a 0.78% improvment in performance in a 3000m time trial.

Have you not considered the possibility that Nike will soon come out with a shoe that is at least as good as the Adidas shoe?