An article of footwear including a sole structure comprising an outsole, the outsole comprising: a first flexure zone extending widthwise from a lateral side to a medial side of the outsole; and a second flexure zone intersecting the first flexure zone and extending lengthwise from at least a toe region to at least a midfoot region of the outsole; intersecting hindfoot flexure zones (216, 218) that divide a hindfoot region into a forward lateral heel region, a forward medial heel region, a rear lateral heel region, and a rear medial heel region; wherein the first and second flexure zones define, together with medial or lateral outer edges (235, 240) of the outsole, at least a lateral toe region, a medial toe region, a forward lateral forefoot region, and a forward medial forefoot region, and wherein at least two of the lateral toe region, the medial toe region, the forward lateral forefoot region, and the forward medial forefoot region include a plurality of fin traction elements, wherein the article of footwear comprises at least a first side-extending fin traction element protruding outwardly from an exposed medial or lateral side surface of the outsole, and wherein a proximate outer edge of the outsole, beyond which the first side-extending fin traction element extends, borders the medial or lateral toe region, the forward medial or lateral forefoot region, a rear medial or lateral forefoot region, the forward medial or lateral heel region, or the rear medial or lateral heel region, wherein the first side-extending fin traction element extends in a toe-heel length direction, that is its longest dimension, and wherein a central section of the first side-extending fin traction element along said toe-heel length direction protrudes outward to a greater extent, relative to outer length sections of the first side-extending fin traction element along said toe-heel length direction, from said exposed medial or lateral side surface of the outsole. a first flexure zone extending widthwise from a lateral side to a medial side of the outsole; and a second flexure zone intersecting the first flexure zone and extending lengthwise from at least a toe region to at least a midfoot region of the outsole; intersecting hindfoot flexure zones (216, 218) that divide a hindfoot region into a forward lateral heel region, a forward medial heel region, a rear lateral heel region, and a rear medial heel region; wherein the first and second flexure zones define, together with medial or lateral outer edges (235, 240) of the outsole, at least a lateral toe region, a medial toe region, a forward lateral forefoot region, and a forward medial forefoot region, and wherein at least two of the lateral toe region, the medial toe region, the forward lateral forefoot region, and the forward medial forefoot region include a plurality of fin traction elements, wherein the article of footwear comprises at least a first side-extending fin traction element protruding outwardly from an exposed medial or lateral side surface of the outsole, and wherein a proximate outer edge of the outsole, beyond which the first side-extending fin traction element extends, borders the medial or lateral toe region, the forward medial or lateral forefoot region, a rear medial or lateral forefoot region, the forward medial or lateral heel region, or the rear medial or lateral heel region, wherein the first side-extending fin traction element extends in a toe-heel length direction, that is its longest dimension, and wherein a central section of the first side-extending fin traction element along said toe-heel length direction protrudes outward to a greater extent, relative to outer length sections of the first side-extending fin traction element along said toe-heel length direction, from said exposed medial or lateral side surface of the outsole.