ALPHAFLY AT TRIALS - letsrun please get a definitive statement from USATF

Nike dot com

No, Nike.com let you customize the upper and sole on the Green Next% when they came out last summer. You could pick any upper of the 3 Vaporfly’s and either the current or the small waffled sole that was on the Streak LTs a few yrs ago. I wish they kept allowing for this when the pink ones came out.

What a mess. No one knows what Peter Bromka was wearing in 2019, except Peter Bromka. In 2018, however, he was wearing blacked out AlphaFly prototypes. Numerous people were wear testing them at the time. And regardless of that, he has been hovering around the same minute in his marathon time for the last four marathons, so clearly the shoes aren't the issue here.

larkimm wrote:

And friction would lose you no energy at all? Good luck with running in a vacuum then...

100% return is impossible, but even if it was approached at 95% you're only talking about the energy put into the shoe. Everything else, from overcoming friction, work / heat in the body, etc etc costs energy. The shoes as it is are about 85% return, so there's not much more that will be extracted.

"Energy return" in shoes is usually assessed by bouncing a weight off the midsole in just the vertical direction, which I agree does not account for friction losses, but to return literally 100% of all the energy input to it (that is the hypothetical the OP presented), the shoe has to return all of that energy (classical physics definition of "energy" here as a scalar quantity), from all sources in all directions. The shoe in this hypothetical is a perfect 3D spring, basically.

In this hypothetical the horizontal speed of the runner would be constant, rather than fluctuating during the stride like normal. Turning or going uphill I think would also be impossible, a flat straight 26.2 mile course would be needed.

But the hypothetical suggested that you could take one step and then put no more energy into the shoes and they would go, presumably, until you stopped.

Even if there was 100% energy return in the system and you tested it by dropping a weight straight down on it the friction of drag through the air alone would keep the weight from bounding back to the same level from which it was dropped. Otherwise the rebound back to the same level of the initial drop would be essentially storing potential energy, in the form of another equal fall, which would mirror the what was first put into the sequence and, as I said in my first response, create a perpetual motion machine. That ain't gonna happen because drag and friction exist.

But they already have wheelchair in the marathon. That gives back way more than the energy you put in. They should be banned!

No more Vaporfly Stories. It's Alphafly now! wrote:

Xfinity wrote:

You keep saying this. I don't believe you. I find it hard to believe everyone will be handed a pair. Offer up some proof.

Agree. How'd they know how many of each size to stock at the check-in table? 700+ runners in the trials.

Yeah, I don't see how that would be possible. That would be over 1000 pairs of shoes, unless the entry form for the trials asks "what size Alpha Fly would you wear". That, and the fact if even 500/700+ accepted the shoes, that would put Nike out over $150,000. I doubt that would fly with Nike.

KraftMacAndCheese wrote:

No more Vaporfly Stories. It's Alphafly now! wrote:

Agree. How'd they know how many of each size to stock at the check-in table? 700+ runners in the trials.

Yeah, I don't see how that would be possible. That would be over 1000 pairs of shoes, unless the entry form for the trials asks "what size Alpha Fly would you wear". That, and the fact if even 500/700+ accepted the shoes, that would put Nike out over $150,000. I doubt that would fly with Nike.

You don't do marketing I suppose?

Marketing guy wrote:

KraftMacAndCheese wrote:

Yeah, I don't see how that would be possible. That would be over 1000 pairs of shoes, unless the entry form for the trials asks "what size Alpha Fly would you wear". That, and the fact if even 500/700+ accepted the shoes, that would put Nike out over $150,000. I doubt that would fly with Nike.

You don't do marketing I suppose?

Ya that guy doesn't know what he's talking about. Can you imagine the marketing benefit Nike would get by showing athletes from all different sponsors choosing to wear Alphaflys instead of the shoes provided by their sponsor? Also, that would virtually guarantee that the eventual top 3 would be wearing the shoe, which again, is great for marketing. $150k would be chump change to make that happen (ignoring the fact that the shoes don't cost $300 to produce, as you seem to imply by your 500 --> $150k math).

Th3_D4rk_Kn1ght wrote:

Marketing guy wrote:

You don't do marketing I suppose?

Ya that guy doesn't know what he's talking about. Can you imagine the marketing benefit Nike would get by showing athletes from all different sponsors choosing to wear Alphaflys instead of the shoes provided by their sponsor? Also, that would virtually guarantee that the eventual top 3 would be wearing the shoe, which again, is great for marketing. $150k would be chump change to make that happen (ignoring the fact that the shoes don't cost $300 to produce, as you seem to imply by your 500 --> $150k math).

No one knows how much they will cost, unless I missed it somewhere. No shoe costs what it does to produce, they are made in sweatshops, especially Nike's. Just making a guess on MSRP. I'll believe it when I see it. Nike is known to take care of their own handful of elites, not everyone in a 700+ runner field. I'll eat crow if I'm wrong, but I don't believe it.

On another note, don't the shoes have to be commercially available to the public for anyone to wear them at the Trials?

Raggedman wrote:

But the hypothetical suggested that you could take one step and then put no more energy into the shoes and they would go, presumably, until you stopped.

Even if there was 100% energy return in the system and you tested it by dropping a weight straight down on it the friction of drag through the air alone would keep the weight from bounding back to the same level from which it was dropped. Otherwise the rebound back to the same level of the initial drop would be essentially storing potential energy, in the form of another equal fall, which would mirror the what was first put into the sequence and, as I said in my first response, create a perpetual motion machine. That ain't gonna happen because drag and friction exist.

True. I was thinking of "friction" between the shoe and ground but "air friction" would cause losses too, independent of the shoe.

We're largely arguing secondary points here. Even outside of a can't-actually-exist case of a runner/shoe/environment system with no sources of energy loss, a shoe with ~99% energy return from vertical squishing gets the runner a lot closer to the hypothetical "bouncing along effortlessly" scenario than a shoe with ~75%. I think that's what the OP was getting at.

Marketing guy wrote:

You don't do marketing I suppose?

Fairly certain Nike will spend more money on a pre-race pasta dinner than what it would theoretically cost to put every athlete in the trials in Nike shoes.

And the idea of handing out shoes to everyone.. um, what? Wtf are people smoking.

UA Runner wrote:

Marketing guy wrote:

You don't do marketing I suppose?

Fairly certain Nike will spend more money on a pre-race pasta dinner than what it would theoretically cost to put every athlete in the trials in Nike shoes.

And the idea of handing out shoes to everyone.. um, what? Wtf are people smoking.

Yeah that Hotlanta dude/dudette has to be high on something ! I mean talk is cheap, obviously athletes sponsored by another shoe company would NOT be able to take Nike up on their offer. As for non-sponsored people, maybe, but would they race with them if they got them at the same time as their bib ? Some might I suppose...

Anyway let's hope the IAAF sets a max average stack height of 36mm by the end of the week and that will be the end of the AlphaFly controversy...until Nike appeal the decision !

This is pretty unrelated to the trials obviously but was Brigid Kosgei NOT wearing just a pink pair of Next% in Chicago? I know all the journalism out there is written by morons but almost every single article keeps referring to the shoe she wore being modified or some kind of prototype. Maybe I missed the boat on this early on, but can someone explain this to me? It looks like a regular Next%.

KraftMacAndCheese wrote:

On another note, don't the shoes have to be commercially available to the public for anyone to wear them at the Trials?

No.

deathinparadise wrote:

Yeah that Hotlanta dude/dudette has to be high on something ! I mean talk is cheap, obviously athletes sponsored by another shoe company would NOT be able to take Nike up on their offer. As for non-sponsored people, maybe, but would they race with them if they got them at the same time as their bib ? Some might I suppose...

I forget the exact wording but their first two comments were something like all runners will have the opportunity to run in the AlphaFly. If Nike has an expo style set up or event where the shoe is for sale, that should limit the whole prototype/not available to all debate, right? Sure, other athletes would honor their sponsorship deal, but it would technically be available to all. Of course, this doesn't touching on stack height or plate or the performance debate.

However, HotLanta's wording changed slightly in later posts though, so no idea what their intent was.

I don’t have any insider info, but if the rumor of them being available at the trials is true, it’d be a super smart strategy for Nike to roll up to the expo with like 50 pairs selling for $300/each. Nike would make money off of the deal, save a ton in marketing, and would cover their a$$es with the “reasonably available” clause. Vaporflys sell out all the time, I don’t believe every single person would have to be able to buy the shoes, just to theoretically have the “chance” to. If I were Ward I’d find a way to secure a pair.. would stink to lose to Lagat because his shoes are 2 minutes faster

This sounds much more plausible than the shoes just being handed out to everyone. They could realistically say that the shoes are available to all at that point.

Can't we skip all the technical arguments and just ban them based on sheer ugliness. Look at that photo of Lagat - they just look silly.

I'm only joking to a degree. What if, hypothetically, it turned out they could keep adding more and more height to the foam and keep getting improved efficiency? Would there come a point - let's say when people were running with 100mm of cushioning - when runners would find them so aesthetically disgusting (as they already are in my mind) that they turned against them.

I would argue that aesthetics (based largely on simplicity) is an important aspect of track and field's appeal. Running around with sponges strapped to the bottom of your feet ruins that.

KraftMacAndCheese wrote:

bruce denton's gold medal wrote:

I forget the exact wording but their first two comments were something like all runners will have the opportunity to run in the AlphaFly. If Nike has an expo style set up or event where the shoe is for sale, that should limit the whole prototype/not available to all debate, right? Sure, other athletes would honor their sponsorship deal, but it would technically be available to all. Of course, this doesn't touching on stack height or plate or the performance debate.

However, HotLanta's wording changed slightly in later posts though, so no idea what their intent was.

This sounds much more plausible than the shoes just being handed out to everyone. They could realistically say that the shoes are available to all at that point.

At no point in time did I ever say that "AlphaFlys will be handed out to everyone". I stated something of the notion that they will be available to any and all competitors that would like to utilize them. Stay tuned as to how this "rule" will be fulfilled.

HotLanta wrote:

Xfinity wrote:

You keep saying this. I don't believe you. I find it hard to believe everyone will be handed a pair. Offer up some proof.

Everyone will get the option to have a pair to race in. It's the athlete's personal choice if they want to accept a pair and race in them or not. Believe me or not, I don't give a śhit.

There, you said it will be their choice if they accept a pair. That implies they will be handed out, rather than having to be purchased. Those are the only two options. Either you get handed a pair, or you purchase a pair.