I believe that the original study that confirmed the 4% showed that the efficiency gain was consistent across the running speeds tested. Having said that, they only tested down to about 3hr marathon pace.

The authors of the study produced a spreadsheet with their expected speed gains at different speeds. It translated to 2.5% speed gain at WR pace, about 4% speed gain at 3hr pace and a theorised 4.2% speed gain at slower speeds. However, again only pace down to about 3hr marathon was actually tested.

I don’t have the spreadsheet but there was an episode of That Triathlon Show podcast that had one of the study authors and linked to their pace equivalent spreadsheet.

I should also point out that these results were for the original Vaporfly 4% shoe. I have not actually seen any validated information for the Vaporfly Next% (other than tumbling records :)).

One would assume at least as good results in the next% if not better?
It is good to know but it does not really tell us if this is worth it for the average 4h marathoner.

It’s worth it. What gets lost at times but then brought back up is how much faster your legs recover when racing in these shoes. So say you don’t get the 4%, which I’m sure you do, you can do your long runs in them and feel a lot fresher the next days and thus keep training without as much muscle fatigue. Ran Chicago in October and could actually walk the next day. Still sore but not close to how sore I was when I ran my last marathon in asics Hyperspeeds.

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It’s really interesting. I’ve ran about 4 times in the last week with the turbo 2. I haven’t ran for about 8 months because of knee problems. I really don’t feel sore. I ran 30 mins last night, I’m definitely fatigued, I tried to run this morning and it wasn’t happening. But I should be significantly more sore than I am.

I've noticed that with the Peg Turbo 1 2, 4% and Next%. There seems to be far less wear and tear on the legs and I've never been doing more volume or speed as the past 1.5 years.

Yeah, my cardio is pretty toast and obviously my running muscles are non-existent so I should be significantly more sore. I’m just not. Also if this saves my hips (repaired labral tears) and knee (PCL/LCL reconstruction), I’ll pay the extra money. Anything that saves me from another surgery in the next few years would be wonderful.

A word of warning in this - the band of speed they were tested against was quite narrow plus with what we know now about the spring response of the prosthetic limbs used by Oscar Pistorius, the potency of these is going to vary massively based upon your body mass, velocity and step frequency. I suspect these shoes haven’t been designed specifically for many of us.

Uhhh dude this is Slowtwitch, not Facebook or Instagram.

I suspect these shoes are designed to help nearly everyone on this forum.

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https://www.strava.com/...tes/zachary_mckinney

Not if you want optimal performance.... or specifically, you’ll have both high and low responders.

Not that it is very reliable, the strava data that NYT pulled together I think noted that slower runners benefit more than faster ones, I think it was in the order of slower runners going north of 4% improvement while faster ones were closer to 3%. Some others here have said it benefits heel strikers more as well, not sure there is any science behind that but logically I think it makes sense.

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808 > NYC > PDX > YVR
2024 Races: Taupo

If you scroll back and read my post this pretty much falls in line with what I found personally. At 4'/km that gives you a 2:48 marathon, 4:30'/km gives you a 3:10 marathon. It was between those times that the shoe went from amazing to good. Much beyond that it just becomes just a soft shoe and the 4% becomes more unstable.

Well looks like another world record for the shoes, and some guy that just happened to run in them.. (-;

https://www.townsvillebulletin.com.au/...da2d6c7040429b1383cd

I watched the video of the race, and it looked to be hilly too. A bit of a stretch to say he broke the WR by 27 seconds, more like 9 practically. But 12;51 for a road 5k that is hilly, well not much else to say except that running is moving to a new zip code now..

The shoe is legit

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E-DUB
Chief Janitor @Slowtwitch
Life is short. Dont be mad all the time.

The force of the foot strike is determined by the speed and WEIGHT of the runner. Anyone who thinks a study on this can be done by simply looking at paces is completely wrong.

Returned the 12.5 and went up to a 13, much better fit!

I would highly recommend that you size up if between sizes.

note: the Ekiden colorway is pretty slick!

Does anyone know if the Next%s are available anywhere? They seem to be sold out everywhere.

Last I looked, Eastbay had a few pink for 186. Running warehouse had a few green and plenty
Of pink for full price.

Thanks. Sorry I should have mentioned I am UK based. They wont ship to the
UK - thanks anyway

As I stated in my post at the bottom of page 10...
'I am sure many will tell you differently but IMO the 4% really makes any notable difference around 4'/km pace with me. I've run a 70.3 and a few shorter races at that speed and the shoe feels amazing. This includes running my fastest ever 70.3 in 85' last year. At 5'/km it is a soft shoe, 4;30'/km it's a good shoe and 4'/km it is an amazing shoe.

The Next% feels like it gives more response at slower speed but in terms of performance gains and what pace makes any difference I'm not sold on yet personally. I've only done a few 70.3s during a build block prior to and for the race in Kona and I believe any performance gains were negligible. The fastest race was 90' 70.3 where it felt a good shoe. Maybe I haven't raced fast enough in it to notice that amazing spot I have in the 4%?

That being said I am a more solid triathlete and long legs for my height so what works for me may be different to many. I am sure there are variations due to body types, weights and running styles... but I think a slower runner doesn't get much more than a soft ride IMHO. This is purely based on my own assessment of prior races over the years in regards to my current form of the time and perceived effort while having used different shoes in the past.'

Next vaporfly colour is the BRS edition.

This is limited edition so they won't make it anymore. I called and got a confirmation.

I am surprised being Slowtwitch that there has been no comment on Brett Sutton's latest blog about Vaporfly shoes. Reading it put a lot of what I was already thinking into perspective and cemented my thoughts somewhat on the shoes. I can only assume he is talking about the Next% and not the 4%.

https://team.homeoftriathlon.ch/...e-vapor-help-you-fly

I have only raced in the Next% a few times as per above and I am just so unsure about the shoe for me. At Kona last year my only IM in the shoe and my calf was so tight and I was concerned about damaging it but hey it was Kona so kept the accelerator pressed until it pops, mind you I was packing a relatively small motor generating not a great deal of pace. I never have had calf tightness like I did in any race that I have done and may not be shoe related at all but thinking about my running style, shoe design and with fatigue makes it probable and a lot of sense now.

As I mentioned in my post above I like the 4% and being a heal striker it works giving a soft ride through to 4'/km I really notice the energy response. The Next% feels like a better energy response at all speeds and may partly be due to the different shaping of the sole but maybe if not designed for a heal striker the shoe may never work for me. I happen to agree largely with the shoe review on Fellnr and they consider the 4% a heal striker shoe.

https://fellrnr.com/wiki/Nike_Vaporfly_4%25

After all the initial hype of the shoe and everyone happy to part with large sums of money I am starting to become unconvinced and it seems so are some of the studies (read until the end...). Time decrease of 4:43 over a marathon...

https://www.wired.com/...make-you-run-faster/

I train in the Pegasus Turbo and love that shoe as it is stable at slower pace and gives more energy response at higher pace. The 4% I find an amazing shoe at pace so my best IM shoe may in reality be the Turbo? Anyway something to ponder and trial with in the build up to my next IM in the end of May.

Each to their own and many I am sure will disagree. Just creating some discussion, my take on the shoe and unlikelihood to buy a set of Next% again any time soon. Anyone want to buy a slightly used pair of Next% size 11.5?

How much? And which color? Don’t need another pair but for the right price...

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Haha green but I'm joking. In Australia as well so may be a costly exercise... I want to do some more running in them training and do some comparisons.

What size are you in the 4%?

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https://www.strava.com/...tes/zachary_mckinney