Makes Paper wrote:
Your comment "It is very much about the foam. " puts a significant dent in all the ranting about Nike's "super spikes," which are supposedly faster (and therefore "super") because of the carbon plate, but don't contain nearly as much cushioning as the super road shoes.
No it doesn't. Compare spikes to spikes and road shoes to road shoes. The new-gen spikes have the new foam—and a lot more foam than old-gen spikes. It is very much about the foam.
Hi LabRat
Can you comment on the compliance of the treadmill that you used?
I think it has rubber slats that provide cushioning, so your results may not translate perfectly to a hard road surface.
rk
p.s. at one point, JT Daniels was associated with your university, but I did not see him in the acknowledgments section, I hope he is doing OK.
Hi Rodger, thanks for your comment. We did test on a slatted Woodway, similar to the Barnes paper I believe. I know that was a point of discussion in that paper also. Is your thought that the magnitude of difference between shoes might be larger on harder surfaces like was shown in the work by you and Hoogkamer in the 4% range? I'm familiar with the work showing slightly worse economy on harder decked treadmills, but do we know if the relative change differs between shoes? I saw your comment on twitter, and actually got me curious about that. I have a harder decked Quinton treadmill in the lab. Probably going to move some things around and at least case study test myself to see if the relative differences are similar. I thought Ian Hunter's group at BYU tested on a harder surface, instrumented treadmill in their Vaporfly paper but showed some of the lowest percent improvement values to date in the lit. What are your thoughts on that?
If we're talking coach/physiologist Daniels...I'm actually at Stephen F. Austin State University in Nacogdoches, TX...not sure that he ever passed through here.
dj
yes, that's what I was thinking. I am a vigorous proponent of hard, stiff treadmills for scientific testing. The Lieberman group used a cushy treadmill for a barefoot vs. shod study and that led to flawed conclusions in my opinion.
I've talked with Iain and his force-treadmill has a belt that was quite slippery for the Vaporfly outsole.
I think Barnes used a slat treadmill in part because he was testing spikes. It is hard to beat an old Quinton. Like the 18-60 from the 1970s used by Costil, EC Frederick, Daniels and many many others. We finally sent our last 18-60 to the salvage yard about 6 months ago. The 1990s Quintons actually can flex a fair bit, I'd want to shim up the middle of the span.
As I tweeted, your study looks like a ton of careful work. It was plenty hard to find runners who could run 18 km/hr with RER <1.0 in Boulder, can't imagine finding/trying to get 16km/hr guys in Nacogdoc!
I imagine/hope that your manuscript is in review somewhere.
rk
re: Jack Tupper Daniels, Ph.D. Oops, I've confused SFASU with AT Still University (ATSU) which is in Arizona, not Tejas. You should take my erroneous suggestion that your study seemed to have a JT Daniels influence as a big compliment.
Thanks for the insight, and I appreciate the compliment. That means a lot. Yep, I let the preprint sit a couple days and have submitted it now for review.
Threads like this are why every thread shouldn’t be the wild west on here…thanks for posting! It’s great to interact w a handful of folks willing to accept grounded information. That biomechanical finding regarding step rate and response to the shoes is one of the few concrete mechanical talking points we have in running. Most every other form discussion starts w an athlete or a coach and their hunch or their bias. If I’m wrong - plz link!
It’s so interesting that in this study the more efficient the runner, the less the shoes worked. Reminds me of something Gary Hall said on the Clean Sport Collective podcast about the “super suits” in swimming. He said they provided extra buoyancy that allowed people to get away will subpar swimming form. I wonder if this is what’s happening with the supershoes?
This is a great read! I have been looking into running economy for a potential thesis provided Covid allows it.
Quick question, what was the rationale for using 16km/hr instead of a specific % of VO2max for each participant? I understand the number of trials preventing testing multiple percentages for time reasoning. I know 16km/hr is a common speed but curious as to your thought process.
It would be good if efficiency per shoe size was measured in a few different type shoes. Most men’s shoes are designed on a US8 or 9 last so does the efficiency of the shoe chance as the size get smaller and less cushioning etc and if the shoes are larger? We all hear how each of us like different shoes so it would be good to have a study on this as I don’t think one has been done.
Well, this supports my anecdotal experience.
The Vaporfly has always worked well for me. I caught the Adios Pro 2 and the Endorphin Pro on deals and decided to try them out, but found that they weren't nearly as quick as the VF for me. I was pretty disappointed based on what Jared Ward said and the study that showed one responder doing better in the Endorphin Pro than the VF. But that was my experience -- if you want the best result, stick with Nike.
This is cool research, thank you for sharing. I wonder if the alpha fly would do as well in non-lab conditions … that shoe just sucks so bad to run in unless you have perfect pavement, no camber, few corners, etc. (in most major road races you have the entire road and it’s fine, but this isn’t the case in many triathlons, which is my interest)
Also, in my own treadmill running (also on a Woodway), I’ve noticed significant differences in shoe traction when the deck is not perfectly dry, which could impact results. Not saying this was the case for your experiment, but worth keeping in mind. In particular the first two versions of the vaporfly were really bad on the TM and I’ve had the best luck with Saucony and the Alphafly.
Too bad they didn't test the Atreyu Artist. Foam and a plate, and one hundred bucks.
pbostduria wrote:
This is a great read! I have been looking into running economy for a potential thesis provided Covid allows it.
Quick question, what was the rationale for using 16km/hr instead of a specific % of VO2max for each participant? I understand the number of trials preventing testing multiple percentages for time reasoning. I know 16km/hr is a common speed but curious as to your thought process.
16 kph is probably the most commonly tested speed in the running economy lit and was also one of the speeds used in the other Vaporfly studies done previously. Two of the other VF studies also tested at 14 and 18 kph and saw similar ranges in improvement across those speeds.
I am doing a follow up study currently testing at slower speeds 10-12 kph that correspond to 3:30-4:15 marathoners.
its only 5k wrote:
It would be good if efficiency per shoe size was measured in a few different type shoes. Most men’s shoes are designed on a US8 or 9 last so does the efficiency of the shoe chance as the size get smaller and less cushioning etc and if the shoes are larger? We all hear how each of us like different shoes so it would be good to have a study on this as I don’t think one has been done.
Kyle Barnes study on the VF tested both men and women over a wider variety of shoe sizes and saw similar improvements.
https://pubmed.ncbi.nlm.nih.gov/30374945/hedge fund manager wrote:
This is cool research, thank you for sharing. I wonder if the alpha fly would do as well in non-lab conditions … that shoe just sucks so bad to run in unless you have perfect pavement, no camber, few corners, etc. (in most major road races you have the entire road and it’s fine, but this isn’t the case in many triathlons, which is my interest)
Also, in my own treadmill running (also on a Woodway), I’ve noticed significant differences in shoe traction when the deck is not perfectly dry, which could impact results. Not saying this was the case for your experiment, but worth keeping in mind. In particular the first two versions of the vaporfly were really bad on the TM and I’ve had the best luck with Saucony and the Alphafly.
We didn't have any issues with treadmill traction for any of the shoes. As for the road application...I'd agree that from a practical perspective, there are some courses that the Alphafly might be less reasonable to use than more typical shoe like the Vaporfly. However, like you said that is probably not a concern at most major road races.
tarckstar wrote:
Too bad they didn't test the Atreyu Artist. Foam and a plate, and one hundred bucks.
EVA. You can get an EVA foam+carbon plate zoom fly for 60 bucks on ebay. Not a supershoe.
Thank you for the reply! I will certainly read more of your research and reach out via email to learn more about your lab!
lab rat rundown wrote:
We didn't have any issues with treadmill traction for any of the shoes. As for the road application...I'd agree that from a practical perspective, there are some courses that the Alphafly might be less reasonable to use than more typical shoe like the Vaporfly. However, like you said that is probably not a concern at most major road races.
It would be awesome if next time you could add in a non-carbon plated shoe that still uses the pebax foam. Reebok Floatride Run Fast Pro would be a great to compare.
lab rat rundown wrote:
its only 5k wrote:
It would be good if efficiency per shoe size was measured in a few different type shoes. Most men’s shoes are designed on a US8 or 9 last so does the efficiency of the shoe chance as the size get smaller and less cushioning etc and if the shoes are larger? We all hear how each of us like different shoes so it would be good to have a study on this as I don’t think one has been done.
Kyle Barnes study on the VF tested both men and women over a wider variety of shoe sizes and saw similar improvements.
https://pubmed.ncbi.nlm.nih.gov/30374945/
Thanks for the reply, this is like other studies where they matched weight between shoes and I could size the distribution of shoe sizes. I was expecting not runners and looking at the efficiency per size and where the the real changes occur mainly due to weight etc
Cool study.
Interestingly, the triathlon world is very much on the Asics bandwagon. Both Olympic triathlon champions wore Asics shoes. Kristian Blummenfelt, the male champion, mentioned on a podcast that he switched from the Nike AF/VF to Asics after he tried them and confirmed he had lower lactate values in workouts. He is part of the Norway triathlon team that is famous for measuring and evaluating everything. Once he made the change, many professional triathletes followed, so the Olympic Triathlon was full of the Asics shoe. Some of the difference in shoe representation between Nike and Asics is likely due to sponsorship in the given sports.
Anyway, this also explains some of Sara Hall's rapid improvement in the last couple years despite not wearing Nike shoes.
If you are unsponsored, I would make sure you got paid a lot of money before accepting a sponsorship with an inferior shoe. And definitely try out the different shoes and figure out which gives you the best result.