A sole assembly for an article of footwear has a first portion having a lower ground engaging surface, an upper surface, and a recess formed in the upper surface. A second portion is seated in the recess in the first portion and has an upper surface. The second portion is formed from a first foam material prepared by a reaction product of a composition having about 10 to about 100 phr of a hydrogenated copolymer and about 10 to about 90 phr of a copolymer of ethlylene and an alpha olefin, the alpha olefin having up to 20 carbon atoms. The first foam material has a hardness of 25 to 45 Asker C and a density of less than 0.18 g/cm3.