A prosthetic system comprising: a prosthetic foot including an upper foot element having a concave-forward facing portion and a foot portion extending forwardly therefrom, an intermediate foot element disposed below the upper foot element and having a front portion coupled to the foot portion of the upper foot element, and a lower foot element disposed below the intermediate foot element such that the intermediate foot element is located between the upper foot element and the lower foot element, wherein the upper foot element and the intermediate foot element are movable relative to one another upon movement of the prosthetic foot; and a pump system coupled to the prosthetic foot and comprising: a pump mechanism including a housing defining a cavity and a membrane situated in the cavity, the pump mechanism movable between an original configuration in which the volume of a fluid chamber defined between the membrane and a bottom of the cavity is zero or near-zero, and an expanded configuration in which the volume of the fluid chamber is increased, the pump mechanism coupled to the upper foot element, characterized in that an arm member extends from the pump mechanism and is operatively coupled to the intermediate foot element, the arm member arranged to move the pump mechanism toward at least the expanded configuration upon movement of the intermediate foot element relative to the upper foot element, further comprising an ankle portion rotatably attached to the upper foot element; a connection unit connected to a rear portion of the ankle portion and a rear end portion of the intermediate foot element, the connection unit being arranged to move the upper and intermediate foot elements (14, 24) relative to one another; and wherein the ankle portion is adapted to rotate in a counter-clockwise direction and the connection unit is adapted to push the rear portion of the intermediate foot element away from the upper foot element when the prosthetic foot is in expansion, increasing a distance defined between the intermediate foot element and the upper foot element. a prosthetic foot including an upper foot element having a concave-forward facing portion and a foot portion extending forwardly therefrom, an intermediate foot element disposed below the upper foot element and having a front portion coupled to the foot portion of the upper foot element, and a lower foot element disposed below the intermediate foot element such that the intermediate foot element is located between the upper foot element and the lower foot element, wherein the upper foot element and the intermediate foot element are movable relative to one another upon movement of the prosthetic foot; and a pump system coupled to the prosthetic foot and comprising: a pump mechanism including a housing defining a cavity and a membrane situated in the cavity, the pump mechanism movable between an original configuration in which the volume of a fluid chamber defined between the membrane and a bottom of the cavity is zero or near-zero, and an expanded configuration in which the volume of the fluid chamber is increased, the pump mechanism coupled to the upper foot element, characterized in that an arm member extends from the pump mechanism and is operatively coupled to the intermediate foot element, the arm member arranged to move the pump mechanism toward at least the expanded configuration upon movement of the intermediate foot element relative to the upper foot element, a pump mechanism including a housing defining a cavity and a membrane situated in the cavity, the pump mechanism movable between an original configuration in which the volume of a fluid chamber defined between the membrane and a bottom of the cavity is zero or near-zero, and an expanded configuration in which the volume of the fluid chamber is increased, the pump mechanism coupled to the upper foot element, characterized in that an arm member extends from the pump mechanism and is operatively coupled to the intermediate foot element, the arm member arranged to move the pump mechanism toward at least the expanded configuration upon movement of the intermediate foot element relative to the upper foot element, further comprising an ankle portion rotatably attached to the upper foot element; a connection unit connected to a rear portion of the ankle portion and a rear end portion of the intermediate foot element, the connection unit being arranged to move the upper and intermediate foot elements (14, 24) relative to one another; and wherein the ankle portion is adapted to rotate in a counter-clockwise direction and the connection unit is adapted to push the rear portion of the intermediate foot element away from the upper foot element when the prosthetic foot is in expansion, increasing a distance defined between the intermediate foot element and the upper foot element.