Wore vapor flys for 5k today and pred by 1 minute.

It's a placebo. You thought they would make you faster, so they did.

Based upon the poor spelling?

Vaporflies are going to be a much bigger deal for master's runners than for run-of-the mill elites. All that cushion and bounce are going to let us run like we did 5 years ago. You can rail against springs all you want, but you're going to have to pry my Vaporflies off my cold, dead feet.

While you're at it might as well go to the anti aging clinics and get some Androgel.

Hobbyjoggerbob wrote:

Now to be fair I’m not a super fast runner. I am 45 years old and had a 5K PR (for 40s). of 20:45 I went out and purchased a pair of the vapor flys last week. I didn’t wear them tell today. I ran a 19:53 time. Course was flat and fast. But still ...

I wonder if they will take a minute off of my 5K PR as well? I set my 5K PR back in 1984 on a flat and fast course. Yep, I can see the headline now, "60 year old man runs 13:08 5K".

Is Wejo the OP wrote:

Based upon the poor spelling?

If VaporFlys did anything, we would be seeing WRs falling left and right...

Oh wait.

Hobbyjoggerbob wrote:

Now to be fair I’m not a super fast runner. I am 45 years old and had a 5K PR (for 40s). of 20:45 I went out and purchased a pair of the vapor flys last week. I didn’t wear them tell today. I ran a 19:53 time. Course was flat and fast. But still ...

Today I ran the Amsterdam marathon in a pair of black Adidas Adios. Not only did I PR by nearly 2 mins, I won the race and nobody in VF Next% could beat me. Their shoes were pink and green, but still...

Truth Bomber wrote:

It's a placebo. You thought they would make you faster, so they did.

Bullsh!t.

Do the test - Buy one pair of Nike Odyssey React Flyknit and buy one pair of Nike Zoomfly Flyknit.

You'd have to be an absolute idiot to claim placebo effect after trying two pairs of shoes of comparable weight, both with exactly the same react sole, but one having a carbon fiber plate and the other not...

Good idea - LRC should run a controlled study on that basis. Get two well trained peak condition groups and get them both to run 10ks a week apaet. One group goes Odyssey then Zoomfly and the other group the reverse. Then look at the times. We'd know the plate effect averaged over the size of the groups and averaged over being used first or not.

BS.

I ran recently 5k in VF4% being in much better shape than before when set my previous PR and was able to improve only by 15 sec. OK I didn't specifically prepare for the 5k race as my training was focused on half-marathon but still it's not huge improvement considering I am 16:2x runner.

To take off 1 minute from 5k it means you were significantly better prepared even as a 20:xx runner. It means you ran each 1k about 12 seconds faster than previously which is like suddenly you can hold your 5k pace for half marathon. That just doesn't happend out of thin air

There is no way that VFs explain a 1 min PR improvement in a 5k. I have personally done time trials in VFs and Saucony Type A8 racing flats and there is zero difference between the two in distances under a mile. Zero.

As the distances lengthen, the extra cushioning in VFs starts to win out over racing flats - but, at 5 kms, it wouldn't be by much.

In my city, the local run club operates 5k races on the same course and I have done several of these in the past three years - my times are entirely subject to temperature, windspeed, and how rested I am on the mornings of the race. I have worn VFs exactly twice and while both were PRs, they were PRs by less than 5 seconds. But both days were cool with light breezes.

The VF is a fast cushioned marathon shoe that is also equal to racing flats in performance and weight.

Interesting! wrote:

Good idea - LRC should run a controlled study on that basis. Get two well trained peak condition groups and get them both to run 10ks a week apaet. One group goes Odyssey then Zoomfly and the other group the reverse. Then look at the times. We'd know the plate effect averaged over the size of the groups and averaged over being used first or not.

It's a hot enough topic. I bet LetsRun could get crews together in a handful of cities to try this. Race on back to back weekends- same pack of folks in each race. 10K could work, 5K recovery is easier, so maybe that's better for back to back?

I'm a man in 17:00 shape in New England. I haven't raced much, so my fitness could be variable but I'll play along if the pack gets that slow.

Brojos- How about a little bit of investigative journalism?

Some slush from the LRC coffers to defray shoe costs?

Some slush from a competing shoe manufacturer to show that it's all placebo?

Lets Run Mob: Can anyone tell us how many racers we need for statistical significance?

This experiment is a cool idea.

As for sample size, I'd begin with 30 in each group (kind of the golden rule in statistics, even though 30 is pretty arbitrary). From there, we'd need to know what sort of effect size we are looking for ( I guess we could go with the work of Tucker or similar), in order to obtain adequate statistical power. We'd obviously want the races run in close to identical weather conditions too.

Once again......I have the 4% for about a year now and have done the running and racing in them experimenting with the heart rates I run at with them on compared to Hoka Clifton.

Its not close. I did a 10 mile time trial at a HR of 80% in both shoes. The 4% were ran 4 minutes faster over 10 miles with the same HR.

One of the benefits that people never talk about is the feel you have the next day (or lack thereof). You can run a hard race in them and you feel less fatigue the next day.

Truth Bomber wrote:

It's a placebo. You thought they would make you faster, so they did.

Yet the results are real nonetheless.

Gonna be an Age Group record breaker wrote:

Hobbyjoggerbob wrote:

Now to be fair I’m not a super fast runner. I am 45 years old and had a 5K PR (for 40s). of 20:45 I went out and purchased a pair of the vapor flys last week. I didn’t wear them tell today. I ran a 19:53 time. Course was flat and fast. But still ...

I wonder if they will take a minute off of my 5K PR as well? I set my 5K PR back in 1984 on a flat and fast course. Yep, I can see the headline now, "60 year old man runs 13:08 5K".

Had to get your time in there. Humblebrag (but it's probably a BS time anyhow)

BYU, led by Ian Hunter and Jared Ward already did this study.

They measured running economy (via body and blood metrics) for a bunch of athletes with and without the shoe in question. They tested each athlete with and without the shoe, at different paces, etc. It was thorough.

Result was that the shoe helps by about 2.5%. While that's not 4%, you bet that's hella significant.

But everyone already knows about the "running economy" findings. It's not the same as "4% faster." There haven't been any prospective studies to establish they're faster, or by how much. (For the record, I do think they are faster, but that doesn't change the fact no prospective studies have established this.)

I'd be interested in seeing Ward's paper. I'll have to look it up.

But also, shhhh, we're trying to gain momentum here to have letsrun pay for a bunch of shoes for slouches to race in for science.