and ultimately, you know, it really engages the brands to make a product that's just as good, that fits under the rules and relations —— regulations. for those of us not elite level athletes why is stack height so important? it’s athletes why is stack height so important?— important? it's the amount of shoe mention _ important? it's the amount of shoe mention -- _ important? it's the amount of shoe mention -- measured i important? it's the amount of. shoe mention -- measured from shoe mention —— measured from your foot to the ground. the shoes that produces the records, the nike vaporfly, it has a carbon plate in the middle of a bunch of film. it will combine with the plate and give you more flight and propulsion. it will give you a 2.5% increase in performance. one the most famous examples is kipchoge in recent years, and a lot of fuss made over that. until now, it was anything