TheUltraboost PB is a stylish, everyday running shoe from Adidas, using the same midsole and outsole technologies as the Ultraboost 20 to give a plush, bouncy, fast ride. This midsole uses Adidas' popular and super springy 'Boost' foam, which is made from fused TPU beads for high energy return. This gives 'bounce' and durability on a run TheTerrex Speed Ultra is soft on flex at 24.3N in our flex test which is great and makes the shoe feel more like a part of your body than an extension of it. In colder temps the Adidas Boost midsole foam performs well too, only stiffening slightly to 29.1N (19.8%), compared to the average midsole (35.3%). Both longitudinally and torsionally ExpertAdvice / Running / Road-Running adidas Ultraboost 22: Tested Review In the latest update to adidas' Ultraboost road shoe, recovery runs have never SyIeQRp.