A footwear sole structure includes a midsole having a ground-facing surface with a forefoot region, a midfoot region, and a heel region. The midsole defines downwardly-extending protrusions at the ground-facing surface distributed over the midfoot region and the heel region, each of the downwardly-extending protrusions having a convex outer surface. A height of the midsole is greatest at the midfoot region. The sole structure may also include an outsole covering at least a portion of the ground-facing surface of the midsole, and a height of the sole structure may be greatest at the midfoot region.