Nike Vaporfly shelf life - Does the foam degrade when they aren't being worn?

I’m was actually just wondering the same thing. Have 2 half’s and a few workouts on a pair but haven’t worn them since last August.

I doubt the foam degrades much at all if they’re not store in sunlight or a very hot environment.

Even then, I think that those two causes of degradation are minimal compared to the mechanical wear caused by running and compressing and decompressing the foam hundreds of thousands of times.

Yeah I feel like they aren't as special underfoot as when they were new.

Is it because they're 2 years old or because of the 60 miles I put in? I don't know.

Maybe it's just me trying to figure out reasons to buy a new pair. Haha

Thanks for your help

I've wondered this myself, and never been able to get a complete answer. I would guess, say, 5 years is probably too long (though I don't know how modern foams age compared to previous cushioning materials), but I doubt that 1-2 years is a problem. At least, I hope not!

I've seen that, when brand new, a pair of next% can be stored for months with minimal degradation; when you finally use them, they feel exactly as they are supposed to feel.

But, I believe that, when used (already exposed to dirt), and stored, even after cleaning, foam degrades much faster and gets prone to lose some of it's responsiveness.

With no events scheduled since march, I just did what you said; use the current pair for workouts and keeping motivation; and stored a new pair and have it ready for next year (hopefully)

I've heard some Nike guys say that the foam degrades and should be as fresh as possible, but none of them were shoe guys, and I got the distinct impression that they don't know anything at all.

So that's my not helpful response.

800 dude wrote:

I've heard some Nike guys say that the foam degrades and should be as fresh as possible, but none of them were shoe guys, and I got the distinct impression that they don't know anything at all.

So that's my not helpful response.

Haha not so helpful but it made me laugh. Thank you

HobbyJogging wrote:

I've seen that, when brand new, a pair of next% can be stored for months with minimal degradation; when you finally use them, they feel exactly as they are supposed to feel.

But, I believe that, when used (already exposed to dirt), and stored, even after cleaning, foam degrades much faster and gets prone to lose some of it's responsiveness.

With no events scheduled since march, I just did what you said; use the current pair for workouts and keeping motivation; and stored a new pair and have it ready for next year (hopefully)

Nah. Polymer (the foam) degradation isn't going to be affected by a little dirt on the outside surface within the time of a couple years. Even oxygen (air) exposure isn't going to have much effect on large molecules like those in the foams. I would estimate that the measurable causes of degradation would be:

1. Mechanical aka use

2. UV exposure aka sunlight

3. High temperature

but number 2 and 3 will be negligible compared to 1.

Without use (only in storage) the adhesive between the foam and the outsole will definitely degrade noticeably before the foam.

any degradation due to sitting in a closet would take probably a decade or more.

leaving them exposed to bad weather is a different story but nobody is talking about that

I've had my 4% flyknit for around 2 years, around 200 miles on them. They aren't as bouncy as when they were new but there still in great shape.

Be honest with yourself, you just want to buy some new shoes! And if you have the money, then why not?

Perhaps more important is the mileage limit for the Vaporflys. Some posters on here have said they lose their advantage after 150 miles. A Nike rep told me personally not to exceed 250.

I read an article that says the glue is what degrades, anyway Ill try to find it. I could be totally off.

If I'm remembering correctly, we have something like 3 years. However, I have 2 vffk and 4% and I wore them in hmm maybe it was July and they are still legit.

Cool dry place, out of light is the storage grail. Hell, I still have the breaking 3 zoomfly1. I love running in those, I feel Kip is pacing me to turkey trott glory.

runderun wrote:

I've had my 4% flyknit for around 2 years, around 200 miles on them. They aren't as bouncy as when they were new but there still in great shape.

Be honest with yourself, you just want to buy some new shoes! And if you have the money, then why not?

I know. That's part of it. I'm kind of a shoe freak. There's also a part of me that wants to be sure that I get 100% of what the shoe can give me on race day.

I don't like the idea of ​​having a 400$ pair of shoes sitting in my closet (yes that's what they cost me here in Canada) but at the same time if I start using them for my workouts they'll be shot in one training cycle. Which doesn't make much sense either.

I think I got used to the idea of ​​keeping them exclusively for my races after reading your comments. They'll probably still do better than most attempts from other brands anyway.

Thank you all

I did around 150 miles of racing in my FK 4% then the Next% came out. I made the Next % my race shoe and started using the 4% for key workouts. I wouldn't use them on a weekly basis, if I did they'd be ruined in a month

ZoomX, you wanna buy the new shoes, so do it. If these shoes are so F-ing light I bet 60 miles is a shi+ ton. Remember the Nike Mayfly? 60 was all that shoe was made for. This is far from that but for cutting edge ultra light flats, I bet they are beat to shi+ after 60 10 minute miles. Maybe not, but you want new shoes either way and that is fine.

The whole "foam degradation" BS is one of many things made up by running shoe company marketing departments to get you to buy new shoes instead of buying old discounted models

If you let them sit in your closet for more than six months they will be old and outdated.

There will be a newer, better and faster 5%, a 5% Beyond, etc.models being released, especially in an Olympic year.

Even the shoe laces will be better.

Wear those old shoes and you will be smoked by lesser runners wearing the latest/greatest technology.

You really need to plan your training, peaks and race schedule to coincide with the new model releases to do well (unless you are sponsored).

The top pros gain an edge by wearing very new shoes that still retain extra energy

(at the molecular level) from the recently completed manufacturing process.

When shoes start to loose that nice new shoe synthetic smell, they start to lose their pop. Shoes with a stronger smell are fresher and faster.

You may not actually run faster in the newest shoes, but your perceived effort level, heartrate, and efficiency will all be better. And you will recover faster. You can best prove this for yourself by racing an all out marathon wearing a different shoe on each foot.

Top shoe marketing gurus, people with better prs than me, and runners that looked relaxed told me all this, so its truth.

Just don't use them for fast workouts or long runs.

I have a 2yr old pair of 4%s that are beat to hell and have over 400mi on them, at least.

I still take them out for easy days or mellow tempo runs. Funny thing is their still light-years better than turbos or zoomfly.

Appreciate your input. Thank you.

I would love to do that, but it is not an easy task. We're quite dependent on Nike releases and espacially being lucky enough to get a pair. We have even fewer releases in Canada and the shoes are shipped overseas from the Netherlands if I remember correctly. In fact, I got my 4% the day after my first marathon ending up running with my Pegasus Turbo.

I think we have only had one release of the Alphafly since their launch. I might try to grab a pair next time.