Man_Moth wrote:
You're falling for the PR.
I'm not sure how a 5 minute economy test is relevant to marathon performance. Mechanics tend to change quite a lot from the first 5 minutes to the last in a marathon.
I'm also skeptical of the results, given that the Fast-R 2 performed very well in the test, and that is possibly the worst super-shoe I've ever worn.
100% agree and the dramatic fervor around a brand claiming this or that is sometimes laughable.
Adidas also just launched (coincidentally) an "updated" version of the Evo pro and claiming 10% more stack height, 5% more energy return and there was a similar freakout. But what does this really mean? 40mm max midsole - if they have pushed up to the thick stack height they are allowed at best they have gone from about 36mm to the 40. That's 10% - that's also a manufacturing tolerance amount. 5% more energy return is 5% more energy return for a 10x10cm sample of foam on an instron machine in the lab. It's actually 5% more elastically resilient - in a practical sense that doesn't simply translate to 5% on the road when you are running.
Brands are looking to sell shoes. In a world where almost all product is fundamentally the same (same foam suppliers, same textile suppliers, same component injection suppliers and a lot of these shoes are even made in the same factories as each other just on different production lines), this is the USP/UVP running brands try and get you with. "Tested in the lab and x% better than the rest" - you can pick and choose any metric to be x% better at and make that claim.
As for the Puma shoe specifically - it's a maximum of 40mm or 1.5 inches of real estate to do something, think about that. What are they possibly doing so much better than adi, Nike, Brooks, NB, Asics in their 40mm knowing there are basically two things you can put in it - some kind of cushioning element (a foam, a structure, an air bag) and some kind of stiffening element (a plate)?
Like you said, it's just PR.