Next%2 less bouncy than Next%?

sub4 machine wrote:

Have you tried Saucony Cohesion ? Really great shoe.

Salvitore Stitchmo wrote:

runn wrote:

I have a question about the Super Shoes:

My friend and I were discussing this- if you wear custom orthotics would you wear them with carbon plated shoes?

My friend (who used to use orthotics) thinks they might "interfere" with the %, so to speak.

I just wondered what others thought.

They do but how much is tough to know

1) they add weight to the overall shoe. 1-1 an orthotic sockliner weighs more than a standard sockliner. Some can add 2-3 ounces to a shoe which is 50-80 grams. 100 grams weight saving translates approximately to 1% running economy. Easy to see the correlation here

2) They won't do anything to the plate (which has a minimal effect anyway) but they will alter your peak force through the shoe to the ground which is the most important thing in determining how fast you run (it's actually the only thing). New foams are so effective because they are easily compressible and do so fast. Simplistically this means you can optimize how much force you transfer to the ground which in turn gives it back to your mass and propels you forwards. Orthotics are denser materials that compress slowly and dissipate force - both counter to the peak force transfer scenario we are after. How much this is I have no idea. I think you could hypothesize its net impact is also somewhere between 0.5 and 1% though full disclosure this is just a guess.

So maybe in total you might see a 1-2% reduction in benefit using the clunkiest orthotics if that's what you needed to use. I guess that's somewhat significant but again, just an educated guess.

runn wrote:

Salvitore Stitchmo wrote:

They do but how much is tough to know

1) they add weight to the overall shoe. 1-1 an orthotic sockliner weighs more than a standard sockliner. Some can add 2-3 ounces to a shoe which is 50-80 grams. 100 grams weight saving translates approximately to 1% running economy. Easy to see the correlation here

2) They won't do anything to the plate (which has a minimal effect anyway) but they will alter your peak force through the shoe to the ground which is the most important thing in determining how fast you run (it's actually the only thing). New foams are so effective because they are easily compressible and do so fast. Simplistically this means you can optimize how much force you transfer to the ground which in turn gives it back to your mass and propels you forwards. Orthotics are denser materials that compress slowly and dissipate force - both counter to the peak force transfer scenario we are after. How much this is I have no idea. I think you could hypothesize its net impact is also somewhere between 0.5 and 1% though full disclosure this is just a guess.

So maybe in total you might see a 1-2% reduction in benefit using the clunkiest orthotics if that's what you needed to use. I guess that's somewhat significant but again, just an educated guess.

Thanks for the reply, it's interesting.

I wear Footlevelers and they make a lighter orthotic for running so they aren't clunky but they are slightly heavier than the regular insert that comes with the shoe. I remove the insert in my regular running shoes to put my orthotic in.

I've been trying to ween myself off of orthotics so I'll probably try with and without to see which I like better.

Thanks again.

Salvitore Stitchmo wrote:

runn wrote:

Thanks for the reply, it's interesting.

I wear Footlevelers and they make a lighter orthotic for running so they aren't clunky but they are slightly heavier than the regular insert that comes with the shoe. I remove the insert in my regular running shoes to put my orthotic in.

I've been trying to ween myself off of orthotics so I'll probably try with and without to see which I like better.

Thanks again.

Honestly, if your orthotics are helping you achieve better biomechanical positions (hopefully they are) then the benefit you get from removing them with the shoes will probably be offset by the help they offer to begin with. I wouldn't be doing that for the sake of what sounds like it could be only a marginal reduction in effectiveness/efficiency anyway (using orthotics vs not). Whatever you do don't hurt yourself for the sake of not even a percentage of running economy benefit.

Salvitore Stitchmo wrote:

Probably a couple of things at play

1) Foam supplier consistency. You'd be surprised at how much the same foam from the same supplier can vary - especially across seasons/models. Think of this - Nike forecasts "X" amount of pairs that will use zoom X foam for let's say, a 2 year period (which would cover one model and then an update). They do this because they get a better price on the raw material buying (hypothetically) 1000kg of it vs 2 batches of 500kg. Let's say then the first model uses that 500kg "fresh" while the other 500kg sits in a warehouse in Asia waiting for the update to come out in 24 months time. Over that 2 year period the material doesn't degrade so much it can't be used but it absorbs moisture (through humidity) - maybe is exposed to UV light etc - all these things can make small but noticeable differences. Even when it comes to manufacturing a season later - were all variables the same? Mold temp, humidity in the molding facility - so many factors which again seem inconsequential and don't make "faulty" shoes - but can make midsoles that feel different.

2 Foam "recipe". Like metal used in jewelry, midsoles are never "pure" material - there are always additives to change properties. Think about this - say Nike get 3% returns on the product because of midsole wear/degrading (some people thrash their shoes - even within 30 days) and slightly changing the composition of what goes into that hopper increases durability which cuts that number in half, that's huge. It might make the midsole a little less bouncy/a little heavier but it increases durability which saves them on returns etc.

When you think of a possible combination of both of the above it's easy to see how the first and second versions of what should be the same shoe can be appreciably different.