The invention relates to a device and method for assisting a subject to perform a motion such as a lift. The invention comprises a first anchor attachable to a first side of a joint of the subject's body, a second anchor attachable to a second side of the joint; and an elastic member connecting the first anchor and the second anchor, such that articulation of the joint in a first direction causes deformation of the elastic member and storing of energy, and articulation of the joint in a second direction causes relaxation of the elastic member wherein the energy is released and assists the subject to perform a motion in said second direction. The invention may be used at a subject's waist, ankle, wrist, knee, hip, elbow, shoulder, and/or at least one joint of the back and/or neck.