NYT: Vaporfly gives "bigger advantage than we thought"

Meta-analysis of self reported data gleaned from Strava data. Interesting correlations can be found but no meaningful or useful conclusions can be made from this.

Useless Data wrote:

Meta-analysis of self reported data gleaned from Strava data. Interesting correlations can be found but no meaningful or useful conclusions can be made from this.

If you say so...

deleuze wrote:

Useless Data wrote:

Meta-analysis of self reported data gleaned from Strava data. Interesting correlations can be found but no meaningful or useful conclusions can be made from this.

If you say so...

Without knowing the full history of the runners who set a personal best time in the Nike shoes running the same race in consecutive years there's no way to say how much any time improvement came from the shoes.

If the first year was the persons first marathon the chances are great, assuming the weather is at least as good as the first year, that they will have a significant improvement the following year even if they have the same shoes on their feet. This is just one simple thing that I don't see being controlled for.

Yes, I say so... wrote:

deleuze wrote:

If you say so...

Without knowing the full history of the runners who set a personal best time in the Nike shoes running the same race in consecutive years there's no way to say how much any time improvement came from the shoes.

If the first year was the persons first marathon the chances are great, assuming the weather is at least as good as the first year, that they will have a significant improvement the following year even if they have the same shoes on their feet. This is just one simple thing that I don't see being controlled for.

Yes you must also make sure they ate the same pancakes and peed the same color otherwise no conclusions can be drawn. Give me a break. Some people are getting faster after their first marathon, other people are getting slower as they age. They explained what they did pretty clearly and analyzed it in several different ways. The effect you mention may be true, but then it would be true for other shoes as well.

Yes, I say so... wrote:

Without knowing the full history of the runners who set a personal best time in the Nike shoes running the same race in consecutive years there's no way to say how much any time improvement came from the shoes.

If the first year was the persons first marathon the chances are great, assuming the weather is at least as good as the first year, that they will have a significant improvement the following year even if they have the same shoes on their feet. This is just one simple thing that I don't see being controlled for.

These are not variables that depend on shoe choice. Try again.

Useless Data wrote:

Meta-analysis of self reported data gleaned from Strava data. Interesting correlations can be found but no meaningful or useful conclusions can be made from this.

People will come to conclusions with or without sufficient evidence. At least conclusions based on this analysis have a higher probability of being right.

Yes, technically this analysis is not conclusive, but what too many people conclude from that is, "Well your evidence isn't sufficient to prove your conclusion, so therefore I will continue to insist that my contrary conclusion is correct with zero evidence at all."

If you read the whole article, this analysis was very carefully done with multiple analysis methods to exclude as many correlations as possible. When the result from every possible analysis method consistently points to the same conclusion, that is at least suggestive that this conclusion has a higher probability of being correct. Yes, at this point it cannot be proven beyond a shadow of a doubt that there isn't some correlation that was present in all of the methods, but the results are so consistent and significant that any reasonable person would have to conclude that if you were going to bet money on this that the odds are in favor of the claim that the VFs do in fact have an advantage.

Useless Data wrote:

Meta-analysis of self reported data gleaned from Strava data. Interesting correlations can be found but no meaningful or useful conclusions can be made from this.

Yeah, all data is "useless" if you refuse to actually look at it or pay attention, and stick with your "gut".

One important factor they didn't control for: these shoes are very expensive and short-lived, and so most runners need some justification for spending so much on them. If you've had a great training cycle and spent lots of hours training to try to hit a PR, it's easy to justify spending $250 to try to lock in those gains. On the other hand, if you've been half-assing your training and know you're not going to run a great time in your next race, you're probably just going to run in whatever lightweight trainers you already have.

Another complaint: if you look at the charts, the baseline for the 4%-5% gain is a heavy trainer like a Brooks Ghost or a New Balance 880. No serious runner is wearing these in a marathon. Compared to the Zoom Streak, a very traditional road racer, they only show about a 2% gain.

More interesting is that strava data also showed they were the 'fastest' shoe (probably because people wore them for workouts and races rather than trainers and recovery shoes - excluded), the average pace is something like 8:12/mi.

Discusser wrote:

One important factor they didn't control for: these shoes are very expensive and short-lived, and so most runners need some justification for spending so much on them. If you've had a great training cycle and spent lots of hours training to try to hit a PR, it's easy to justify spending $250 to try to lock in those gains. On the other hand, if you've been half-assing your training and know you're not going to run a great time in your next race, you're probably just going to run in whatever lightweight trainers you already have.

Another complaint: if you look at the charts, the baseline for the 4%-5% gain is a heavy trainer like a Brooks Ghost or a New Balance 880. No serious runner is wearing these in a marathon. Compared to the Zoom Streak, a very traditional road racer, they only show about a 2% gain.

I think the first factor is probably pretty marginal. Do not think that would account for that much difference.

The second complaint seems to be the most valid of the 4-5% claims as it seems like we're working from a baseline of 1.5%-2.5% so its not as pronounced. That being said maybe that is being washed out by the fact that the claims are for running efficiency not speed.

Discusser wrote:

One important factor they didn't control for: these shoes are very expensive and short-lived, and so most runners need some justification for spending so much on them. If you've had a great training cycle and spent lots of hours training to try to hit a PR, it's easy to justify spending $250 to try to lock in those gains. On the other hand, if you've been half-assing your training and know you're not going to run a great time in your next race, you're probably just going to run in whatever lightweight trainers you already have.

Another complaint: if you look at the charts, the baseline for the 4%-5% gain is a heavy trainer like a Brooks Ghost or a New Balance 880. No serious runner is wearing these in a marathon. Compared to the Zoom Streak, a very traditional road racer, they only show about a 2% gain.

Only 2%? That's still pretty significant--more significant than a lot of people have been claiming. A lot of people are claiming it gives no advantage, and other people were claiming it gives 1-1.5%. Absolutely no one was claiming it improves race times by 4% in the real world. The 4% claim was always about some kind of theoretical running efficiency which does not mean a 4% improvement in race time. 2% improvement in actual race times is a pretty big deal.

Funny you should mention the zoom streak in your second point though, because if you take that back to your first point, how many people do you think run marathons in zoom streaks if they're half-assing it and not planning to run a great time? Price isn't the only factor here. Yes, your point is well-taken that people who are trying hard are more likely to be willing to spend more on a shoe, but rich people will also pay a lot for a shoe even if their training or ability doesn't justify it just for the prestige of having the perceived best equipment. And there are other shoes that people who are really seriously trying hard would run in--like the zoom streak. So if it's all about a correlation with shoes that would be chosen by try-hards, then there should be other shoes than the VFs that should show that same effect. Arguably the zoom streaks being 2nd on the list shows the full extent and limitations of that effect, and the VFs far exceed even that.

HOKA with the slowest shoes out there!! No wonder Sage can't qualify for the Trials!!

Discusser wrote:

Another complaint: if you look at the charts, the baseline for the 4%-5% gain is a heavy trainer like a Brooks Ghost or a New Balance 880. No serious runner is wearing these in a marathon. Compared to the Zoom Streak, a very traditional road racer, they only show about a 2% gain.

1-2% is huge at elite sport.

wejo wrote:

Discusser wrote:

Another complaint: if you look at the charts, the baseline for the 4%-5% gain is a heavy trainer like a Brooks Ghost or a New Balance 880. No serious runner is wearing these in a marathon. Compared to the Zoom Streak, a very traditional road racer, they only show about a 2% gain.

1-2% is huge at elite sport.

Yeah agreed - I'm surprised people are saying "only" in the context of a 2% performance gain. That's a bit over 2 minutes for a good marathoner and 18 seconds for a 15 flat 5K. It's a little more than I would have guessed - as someone who wears the shoes I would have put it more in the 1.5% range.

Also worth noting that the benefit will vary based on the runner and if you are a forefoot striker, heel striker, etc. I also personally think that they help more at faster paces and that it benefits me more in a 5K than in a marathon.

Would be interesting to compare to spikes on the track to figure out what is best to wear in a race like a track 10K.

Buster Cherry wrote:

wejo wrote:

1-2% is huge at elite sport.

Yeah agreed - I'm surprised people are saying "only" in the context of a 2% performance gain. That's a bit over 2 minutes for a good marathoner and 18 seconds for a 15 flat 5K. It's a little more than I would have guessed - as someone who wears the shoes I would have put it more in the 1.5% range.

Also worth noting that the benefit will vary based on the runner and if you are a forefoot striker, heel striker, etc. I also personally think that they help more at faster paces and that it benefits me more in a 5K than in a marathon.

Would be interesting to compare to spikes on the track to figure out what is best to wear in a race like a track 10K.

FWIW, Genevieve LaCaze Gregson just wore them and won the 10,000 in the Australian championships.

Da Shoes

A lot of folks have delicate egos invested in these shoes now theyve set PBs everywhere.

The fact WRs are dropping like flies suggests they definitely offer some benefit.

This has got to be the most compelling research done for racing times on different shoes .

I own 6 shoes on the list and it's almost 100% accurate as to the differences in times I have observed wearing those shoes on race day . Now I am really curious to try on the vaporfly .