The invention concerns an electrically rotatable shaft, and more particularly, an adjusting shaft (1) of a fully variable mechanical valve train of an internal combustion engine, said shaft comprising an adjusting cam (2). The low-friction and lash-free configuration of a drive required for a rapid and exact functioning of the fully variable mechanical valve train is achieved by the fact that the adjusting shaft (1) is rotated by an actuator (3) that comprises an adjusting lever (4) connected rotationally fast to the adjusting shaft (1), while the free end of the adjusting lever is articulated preferably on the screw nut (10) of a screw-and-nut drive (5) that is driven by an electromotor (6).