Can we settle on a time conversion for super shoes?

link.springer.com

A Comparison of the Energetic Cost of Running in Marathon Racing Shoes - Sports Medicine

Background Reducing the energetic cost of running seems the most feasible path to a sub-2-hour marathon. Footwear mass, cushioning, and bending stiffness each affect the energetic cost of running. Recently, prototype running...

Link:link.springer.com/article/10.1007/s402...

This research asserts up to 6.26%. My 10 was from what I thought I read in a Ross Tucker article- I stand corrected. However, anecdotally I would have to run numbers on past teammates that I'm sure are nearer to the 7-10% range at least in track races. With collegians now opting for VFs in cross races on grass this opens a new range of things to look at.

Kudos to you, internet sleuth

Interesting. I have done multiple workouts in both the Lunaracer 3 and the Vaporfly in my last half marathon build up. My workout of 5 x 2 miles I did twice in the build up and it yielded 6:27 pace for both workouts in both shoes just two weeks a part.

I do prefer running in the Vaporflys because they just feel nicer and my feet really didn't feel as beat up after a longer effort. It feels like it takes less effort to run in them, but they didn't yield a faster time. It's hard to explain.

How much mass can I save if I saw the pointy heel off the vaporfly?

The benefits will likely differ for each athlete. A heal striker will benefit more than forefoot strikers for instance. Kipchoge seemed to have a stride made for these types of shoes

Same heart rate?

I thought those shoes were one of the first Vaporfly prototypes, ahead of the next-gen prototype pair he wore 11 months later in Rio?

I don’t know how a heel striker is going to benefit more than forefoot striker on the VF. The whole design of the shoe is premised on a mid/forefoot strike that should effectively utilize the plate to get a snappy toe off. You’re already far less efficient heel striking, which is like putting a small brake on the process each step.

The rear half of the VF is super soft while the front half is very firm. I’m not saying heel strikers can’t run in the shoe, just that they are not getting a lot of the benefit that was designed into the shoe.

But I am a forefoot striker.

I weigh 141 lbs, so maybe a heavier runner might prefer them, and supposedly, version 2 & 3 may have improvements over the version 1 I have. But no way I want to spend another $275 to find out, after the first version was such a big letdown, and the VF was significantly faster for me. AF version 1 was just ‘meh’ for me.

Based on my experience with AF version 1, I doubt any slight improvements in the later versions reduce the klunkiness factor I experience with it.

Weights of my (size 9 men’s) shoes:

VF version 1….6.5oz

VF version 2….6.9 oz./6.8 oz.

AF version 1….7.5 oz.

Saucony Endorphin Speed…7.7oz

Kiochoge prefers to race in the VF instead of the AF.

How do the weights compare between your Lunaracer 3 and the VF?

In my experience with the VF, after putting several miles (> 200miles) on them, the forefoot foam compresses out to the point where they start hurting a bit in the forefoot from impact during reps on the track.

He may have been in better shape too.

I may be mistaken but the only marathon Kipchoge did not run in the AF was in the Tokyo Olympics, where he wore a new color way of the VF. His most recent win in the March Tokyo Marathon he wore the AF2, which was about to be released. If you follow his training posts on IG, he’s wearing AF most of the time, and sometimes the Pegasus.

I would be shocked to see him in Berlin in anything other than the AF2. I think the AF2 is a step backwards from the first version. The AF2 was tweaked to be easier to run in than the AF1. The AF2 is wider, heavier, and makes the air pod less intrusive.

Nothing is sadder that someone trying to find excuses for why they lost.

You are greatly mistaken. You have it reversed. He ran in a special, non-commercial version, of the AlphaFly for the sub-2 exhibition. But practically all of his marathons are being run in the VaporFly.

Galen Rupp runs marathons in the AlphaFly, but not Kipchoge.

Bekele also prefers the VaporFly over the AlphaFly.

This was debated a lot back when it first came out. He ran a 2:04 even in broken prototypes so minus a few %. His 2:03:05 the next year however was in London with the Next%. He ran Berlin in 2017 in the rain though so hard to say. And even his 2018 then is so far removed that it's hard to isolate.

I predict there is no way Kipchoge gets the marathon World Record in Berlin if he wears the klunky AlphaFly in lieu of the VaporFly. His sponsor might want him running in the AlphaFly, but there will be no World Record if he runs in it.

The alphaflys came out in 2020 for the US Olympic trials (can't remember if say Eliud had an earlier pair in 2019 but maybe he did). He wore vapors in the Olympics but he wore Alpha 2s (prototypes?) in Tokyo this year.

Edit meaning in 2019 other than Ineos which he obv did Alphas - can't remember if he raced another time - don't think he did.

An independent body (can WA even be trusted) should check the shoes Kiera and Eliad are wearing if they are AlphaFly’s, because there was supposedly a ‘goosed’ version Kipchoge ran the sub-2 in. It supposedly had stacked air-pods between sandwiched plates.

Downvote this all you want, but running great Bekele absolutely prefers the VaporFly over the klunky AlphaFly.

Seth James DeMoor has tested countless shoes, and he too prefers the VaporFly over the klunky AlphaFly.