Dragonfly spikes Cheptegei was wearing: they aren't actually carbon fiber, correct?

You are also forgetting the asterisk spikes and spike plate part of the shoe...

Maybe JC ran the WR in the Dragonfly to dispel accusations of shoe aided?

FYI, the DF does have a carbon fiber plate, but, unlike the Victory, it runs through the rear midsole midway between the foot bed and the outer sole (no propulsion help in the heel unless you are a heel striker like Ritz). It then attaches to the spike plate.

Again, no beneficial bounce here like the Vaporfly.

This WR was all Cheptegie.

And I agree with Canova that its shortsighted to not allow road shoes for 10ks on the track. Bad for the health of athletes.

All good elite runners wear spikes in the 10,000m.

I can see your point but how do we enforce a rule? I think a good idea would be to make official world records to have to have been run barefoot. Anything else should be seen as "equipment enhanced" - a bit like entering the race on a push bike or something. The only problem would be that the shoe companies, who are major sponsors of the sport, would definitely be against this.

old skool wrote:

The only problem would be that the shoe companies, who are major sponsors of the sport, would definitely be against this.

You forgot about all the current WR holders. Almost all of them wore shoes when earning their WRs. What are you going go do, take the current WR holders off the books? Put an * next to their name for not running barefoot?

Bring back the Nike Vainqueur:

http://only-sneakers.ru/tag/nike-vainqueur/

Where did we get to on this?

My point is that whether they did or didn't have a CF plate isn't really the issue, they 100% were / are 'super shoes' and have contributed significantly to this new WR time. Progress is progress but to claim he is a 'superior' athlete to, or his run was 'better' than, Bekele's is non-sense. The time was less, period. That's all a WR is, time. Both immediate and historical. Kudos to Joshua he is absolutely the best runner of his time as Bekele was of his ... and now may soon be at the marathon distance.

W. Hunting wrote:

All good elite runners wear spikes in the 10,000m.

No. Vaporflys were used by some elite runners in the Zatopek 10,000m in Australia and there examples in other races. Not saying they are faster than spikes, but perhaps not slower and with the advantage of better recovery from the race.

Athletes running 10000m on track in Vaporfly are specialists on road, not used to wear spikes, in training too.

The real track runners use spikes, always in competition and in training too. It's not a case that in WCh 2019 in Doha in 10000m (22 runners starting), 21 used spikes and only Moen Vaporfly, because it was too much important to save tendons and feet looking at Valencia Marathon at the beginning of December (Moen had in the past two surgeries and a stress fracture, and can use spikes for a limited time only, and never in training).

Among the 21 athletes in Doha, the top 3 had good knowledge and feeling with racing shoes on the last generation (Cheptegei and Kejelcha with Vaporfly, Rhonex Kipruto with Adidas Zero), and choose to use spikes because on track can allow a higher speed.

It's true that, after the race, the legs of athletes using Vaporfly are more fresh and the full recovery happens in shorter time ; but this has nothing to do with the speed during the race : spikes are very much faster, and there is no reason not to allow athletes running on track with Vaporfly or racing shoes from other Companies with thickness higher than 25 mm.

LOL.

This is the most I've seen a clueless poster destroyed on Letsrun.

The shoes seem to be giving an assist to some athletes this season. The PRs seem to be to much. The recent 5K WR is at a pace that is 60 point for 12.5 laps. How is that possible?

“ Along with ZoomX and a plate, there's also a small sliver of CMP compression foam underneath the heel to increase durability. This shouldn’t have any impact on weight and performance but it was added in to help the shoe hold up a little longer mile after mile on the track. That ZoomX foam is going to work with a full-length Pebax plate for an effortless, propulsive feel. The Dragonfly doesn’t have a carbon fiber plate but the full length Pebax design still helps create that added rigidity and stability needed to run at peak efficiency.”

From Running Warehouse’s message board.

Pebax plate. Basically what has been in mizuno shoes for YEARS. Guess all mizuno shoes should banned now?

boiling wrote:

From Running Warehouse’s message board.

Pebax plate. Basically what has been in mizuno shoes for YEARS. Guess all mizuno shoes should banned now?

Yeah, this once again confirms that ppl are too stupid to understand where the magic happens, obviously it doesn't necessarily have to be a carbon plate to create the same effect. And yes, it's hard to ban a plate design, but we should at least acknowledge that times aren't comparable anymore then. Bekele>>>>Cheptegei

Whatever those studies claim is clearly founded on the fundamental misunderstanding of human gait used by the shoe industry to constantly fleece millions of suckers with endless series of new gimmicks.

That misunderstanding is that something propelling your heel upward can make you go faster. It can't. In fact, your heel is dragged into the air without being pushed by anything, as your own body drags it forward and upward around the TMJ. This happens long after any mechanical reflex from a stiff spike plate (and "stiff" means next to no reflex) and it also happens long BEFORE the most important propulsive forces occur.

What are those most important propulsive forces? Every muscle above your planted forefoot throwing your skeleton upward and forward from it. This is not efficient until the heel is already well off the ground, thus stiffening the arch via the windlass mechanism. Until then, a force exerted downward against the still-loose arch will accelerate the arch downward and reduce acceleration of the leg upward and forward.

Watch a hobby jogger, note how they think running is about pushing down on the ground, like they are hopping from one leg to the other. Then watch an elite runner smoothly throwing their knees forward. The elites don't need gimmicks, they're just paid to use them.

I think the plate on the Dragonfly on is on the outside, if I'm not mistaken, and be carbon couldn't be used because of poor impact resistance. Pebax, in the other hand, can handle getting pounded against the track surface without cracking.

I own both the dragonfly and the air zoom Victory. Both great shoes, but for very different reasons. The dragonfly is very smooth. It is stable for a spike (the reason why I believe Joshua Cheptegei wore it for his 5000 record). The dragonfly is very comfortable for going fast with a cruising style. The victory feels good for going FAST. If you’re not grinding, the victory will not feel good. To address the argument about whether or not the plate in the dragonfly is carbon, it most certainly is not. Personally, I would like for there to be a version of the dragonfly with a CFP, but that does not exist in competition (at least not yet). I have watched all of the DL meetings, and have paid attention to what every elite was wearing. Interestingly, there hasn’t been an absolute correlation between what distance is being run and what shoe is being worn. Runners like J Ingebrigtsen has favored the dragonfly in all races other than the 1500 in Ostrava. Then there have been guys like Barega who use the vics all the way to 10,000. It’s all a matter of preference, but there is a slight favorability of the vic in the middle distances, while the dragonfly is much more solid at 5000-10,000. Personally, I will be using the two interchangeably depending on how competitive the meet is. I really only run middle distances up to 5000, so either shoe can be beneficial.

Renato!

World Athletics becomes even more stupid. Now down to 20mm on track but still 40mm on roads!

https://www.worldathletics.org/news/press-releases/new-athletic-shoe-regulations-approved-2022