A footwear sole, comprising: a midsole having a midsole toe end, a midsole heel end, a midsole lateral side, a midsole medial side, a midsole top surface, and a midsole bottom surface, the midsole bottom surface is comprised of a plurality of protrusions (214, 224) extending downwardly away from the midsole top surface, wherein each protrusion of the plurality of protrusions has a distal end having a convex contour the midsole bottom surface is comprised of a baseline bottom surface; the plurality of protrusions extend downwardly from the baseline bottom surface; an outsole having an outsole toe end, an outsole heel end, an outsole lateral side, an outsole medial side, an outsole top surface, and an outsole bottom surface, the outsole top surface is comprised of a plurality of recesses (314, 316, 318, 319) extending downwardly toward the outsole bottom surface, wherein each recesses of the plurality of recesses has a concave contour corresponding to an associated protrusion of the plurality of protrusions of the midsole, such that the midsole and the outsole are coupled so that the distal end of each of the plurality of protrusions mates to the associated recess of the plurality of recesses of the outsole; and the sole comprises a bonding agent, wherein the bonding agent couples, in some but not all, points of contact between the midsole and the outsole near the perimeter and near a portion of the hemisphere-shaped distal end of a first protrusion, the midsole and the outsole not being coupled near the baseline bottom surface that is remote from the perimeter to form a substantially air-tight cavity disposed between midsole and the outsole, wherein the midsole and the plurality of protrusions are formed from a common material. a midsole having a midsole toe end, a midsole heel end, a midsole lateral side, a midsole medial side, a midsole top surface, and a midsole bottom surface, the midsole bottom surface is comprised of a plurality of protrusions (214, 224) extending downwardly away from the midsole top surface, wherein each protrusion of the plurality of protrusions has a distal end having a convex contour the midsole bottom surface is comprised of a baseline bottom surface; the plurality of protrusions extend downwardly from the baseline bottom surface; an outsole having an outsole toe end, an outsole heel end, an outsole lateral side, an outsole medial side, an outsole top surface, and an outsole bottom surface, the outsole top surface is comprised of a plurality of recesses (314, 316, 318, 319) extending downwardly toward the outsole bottom surface, wherein each recesses of the plurality of recesses has a concave contour corresponding to an associated protrusion of the plurality of protrusions of the midsole, such that the midsole and the outsole are coupled so that the distal end of each of the plurality of protrusions mates to the associated recess of the plurality of recesses of the outsole; and the sole comprises a bonding agent, wherein the bonding agent couples, in some but not all, points of contact between the midsole and the outsole near the perimeter and near a portion of the hemisphere-shaped distal end of a first protrusion, the midsole and the outsole not being coupled near the baseline bottom surface that is remote from the perimeter to form a substantially air-tight cavity disposed between midsole and the outsole, wherein the midsole and the plurality of protrusions are formed from a common material.