@grammar police: I apologize for my imbecility. I would ask, however, that you consider my correct usage of the possessive form throughout the other responses. I ask that not as a pardon or excuse for myself, but rather as a demonstration that I was educated properly and that the American education system and my formative teachers (for whom I have tremendous gratitude) bear no burden for my transgressions. Instead, lay all the blame on me, my carelessness in letting my fingers play will-nilly with punctuation unthinkingly, and my laziness for not proof-reading my response. I'm saddened that my sloth polluted these boards with such indecipherable text (if you could call it that), but I hope you at least could make out some of the other ideas in the surrounding paragraphs and perhaps infer some meaning despite the stylistic afflictions.
However, I will defend my use of "jive" as a verb with respect to runners and the spikes. My hope was to communicate the notion that some runners are able to interact with the Zoom Victory in a fashion similar to the movements of a popular mid-century rock 'n roll dance. I had considered using "foxtrot" or "boogie" (obviously), but each seemed either too structured or chaotic, respectively. Perhaps to clarify that it was a partnered dance, I should have said that some runners "jibely jive" or even "jively jibe" with the Victory more than others. That is to say they "the runner and the new Zoom Victory move in a fashion similar to a popular dance specific to a style of mid-century rock ' roll in a cooperative manner" or "the runner and the new Zoom Victory cooperate in a manner similar to a popular dance specific to a style of mid-century rock ' roll." I think the former gets at it better. I apologize for the attempt at textual economy. I recognize that it may have obfuscated the meaning for many.
I cannot promise that I won't make these mistakes in future posts, but I can promise that I will be more self-aware of the risk and that the probability of their occurrence has been reduced. Thank you for taking the time to serve and protect the stylistic integrity of these boards.
@soups: Another great question. There could be a couple distinct benefits to training in them: first, there does seem to be a reduction in the muscular trauma you'd normally get in a typical EVA running shoe (especially a racing flat). We talked about this on the podcast a bit, and this is largely anecdotal with some small pieces of data. However, this seems to be a pretty unified piece of feedback from people who have run long, hard sessions or marathons in them. I can personally attest this as well - when I do a long session on the roads, my legs have a similar sensation to simply finishing a normal run. That's potentially due to the more compliant and more resilient foam reducing the amount of eccentric work your muscles would otherwise be doing to cushion your body each step. I'd hypothesize the shoes could actually change training paradigms a bit (which may have further trickle down effects in racing performances), as they may allow for more longer specific sessions. That is, they could allow for a higher volume of aerobic stresses without incurring as much structural stress for the body to also recover from. Second, some people may actually find benefit from the plate. Note - we don't have any health/injury studies on this, so this is just feedback I've heard from runners and my own conjecture. That being said, the way each person interacts with that is going to be very unique - things like foot shape, ankle and MTP mobility, foot strike, intrinsic foot muscle strengths and weaknesses, etc. all affect how that architecture will interact with what you bring to it. For some, the plate may serve as a beneficial piece for relieving stresses or supporting certain foot motions in doses. However, if that's true, the opposite is also likely true (next paragraph). Third, I wonder about the ability for our bodies to change or adapt our mechanics over the long-term (even only subtly) to better "use" the technology in the shoe (the high volume of more resilient/compliant foam and that architecture). We know from mechanical studies that runners adapt to new surfaces grossly almost instantly, but I'm curious if long-term training (or development from a young age) in these distinct shoes wouldn't also invoke some sort of gradual shift - maybe slightly longer ground contacts and a bit more vertical oscillation to store more energy in that foam (that's just a napkin example, it could be a number of possible nuanced changes). I would further hypothesize that this might be a bigger deal at faster speeds where runners are used to the responsiveness of the ground "feel". Could a runner train at faster speeds in the VF to better use it to run faster than in a pair of spikes at an elite level? I'd lean towards yes. But again, that's all personal conjecture and musings. I think it's interesting against the example of the "clapskate" in speed skating, where for many, it wasn't initially beneficial, but with sufficient training (there were studies using an 8-week adaptation block), it became faster (4%!).
As for the downsides, the first would be to the point of individualized responses to the plate. That's a very constrained movement path to which it subjects the foot. There may be a lot of people who would struggle to run it because it might overly stress some structures. When I was recovering from Achilles issues, I couldn't wear it, as my limited ankle mobility at the time interacted with it to put stress on that insertion. I've also noticed occasional odd, semi-sharp tendon-type pains after some long runs in them in different joints (foot, ankle, knee at different times). It was never anything that developed into an injury, but rather a reminder that there were different structures in my legs that were getting stressed in slightly novel fashions as compared to my normal trainers. So, that's something to consider against the backdrop of developing with the shoe. I suspect, as is true with many things in the body, that if a novel stress (the plates in these shoes) is introduced gradually with sufficient time for recovery and adaptation before being stressed again, you can mitigate those issues to use them safely. However, I do have to stress that it is a very distinct architecture that each person's body will interact with differently, and should be approached with a bit of caution at first when bringing them into training. Second, and this relates to the injury risk, it seems like the foam packs out relatively quickly. I'd been told by someone at Nike that the compression set is similar to EVA (but he said it should last 200 miles, which is lower than the "typical" recommendation for EVA shoes, ha). I've put over 200 miles on pairs, and they feel like they're still softer and more resilient than EVA, but not as much so as their initial 100-150 miles (but that's also generally consistent with EVA anyways - gradual, albeit nonlinear, performance loss). That's just personal experience and un-quantified (mechanically, speaking) sensation though. My concern with how they wear would be how any wear patterns within the foam (breakdowns) would affect plate position. That's something we may be hoping to unpack (pun intended) in our lab in the coming year. Finally, they're expensive!