Midsole foam
We can’t explore super shoes without discussing how they differ from average trainers. They generally weigh less because the midsoles are made with an ultra-light, high-performance foam called PEBA (short for polyether block amide)—referred to by the brand name Pebax. You can put a carbon plate in an EVA or TPU midsole, but it won’t have the same benefits as the Pebax midsole of a super shoe.
For context, Hebert-Losier offers, “The Nike Vaporfly 4%, the super shoe created for Eliud Kipchoge for his Breaking2 effort, weighed in at 210 grams. By standard, most men’s running shoes weigh 310-320 grams.” That’s a 32 to 35% reduction in weight, providing a nice advantage for an athlete.
But the real advantage is in the foam technology itself. The Vaporfly 4% earned its name because it offers an average four percent running economy, and studies have backed that claim up. Compared to EVA or TPU foams, Pebax is specially engineered to offer explosive energy return. This cushy midsole foam absorbs impact and fights fatigue with the intent to help you run faster and/or longer.
Imagine being able to cruise through a marathon in a shoe that makes it easier to add a little gas to the last miles when other athletes might be hitting the wall. With a benefit like that, you’d think everyone would want to run in super shoes.