An upper comprising an upper body covering an instep of a foot, wherein at least a part of the upper body includes an opening region disposed with an opening and a joint region that is a planar region disposed around the opening region, a plurality of linear first members extending in one direction are arranged in the opening region in a state of not being coupled with each other, both ends of the plurality of linear first members are fixed ends fixed to the joint region of the upper body adjacent to the opening region, order in which fixed ends on one end side of the plurality of linear first members are arranged is equal to order in which fixed ends on the other end side of the plurality of linear first members are arranged, the upper body includes an upper midfoot portion covering a midfoot of a foot, the plurality of first members are disposed on the upper midfoot portion, the upper midfoot portion is disposed with a foot insertion opening for inserting a foot, and a throat portion communicating with the foot insertion opening and extending forward from the foot insertion opening, the plurality of first members extend from an edge of the throat portion toward a sole positioned below the upper body, the upper body includes a second member disposed to overlap the plurality of first members, and the plurality of first members and the second member are disposed in a state of not being coupled with each other, characterized in that stiffness of the opening region in which the linear first members are disposed is lower than that of the joint region adjacent to the opening region, the plurality of first members includes a first extendable member and a second extendable member having higher extensibility in the one direction than the first extendable member, the opening region includes a first region in which a plurality of the first extendable members is arranged, and a second region in which a plurality of the second extendable members is arranged, and the first region and the second region are alternately disposed in a front-rear direction. an upper body covering an instep of a foot, wherein at least a part of the upper body includes an opening region disposed with an opening and a joint region that is a planar region disposed around the opening region, a plurality of linear first members extending in one direction are arranged in the opening region in a state of not being coupled with each other, both ends of the plurality of linear first members are fixed ends fixed to the joint region of the upper body adjacent to the opening region, order in which fixed ends on one end side of the plurality of linear first members are arranged is equal to order in which fixed ends on the other end side of the plurality of linear first members are arranged, the upper body includes an upper midfoot portion covering a midfoot of a foot, the plurality of first members are disposed on the upper midfoot portion, the upper midfoot portion is disposed with a foot insertion opening for inserting a foot, and a throat portion communicating with the foot insertion opening and extending forward from the foot insertion opening, the plurality of first members extend from an edge of the throat portion toward a sole positioned below the upper body, the upper body includes a second member disposed to overlap the plurality of first members, and the plurality of first members and the second member are disposed in a state of not being coupled with each other, characterized in that stiffness of the opening region in which the linear first members are disposed is lower than that of the joint region adjacent to the opening region, the plurality of first members includes a first extendable member and a second extendable member having higher extensibility in the one direction than the first extendable member, the opening region includes a first region in which a plurality of the first extendable members is arranged, and a second region in which a plurality of the second extendable members is arranged, and the first region and the second region are alternately disposed in a front-rear direction.