A dumbbell has an optional number of weight discs which stand on end in a stand, and a handle with anchorages. The anchorages and the weight discs have connecting structures which, in the axial direction, interconnect the anchorages with a neighboring weigh disc or neighboring weight discs, respectively. On the other hand, the connecting structures permit movement transversely of the axial direction. The weight discs display locking structures, which, in the activated state in directions transversely of the axial direction, prevent mutual movements between the weight discs and the anchorages. The locking structures have locking bodies which are movable so that their directions of movement have an axial component and which are disposed at the peripheral regions of the weight discs, and also are insertable in corresponding recesses in a neighboring weight disc or an anchorage. The locking bodies are operable by an operating arrangement located inside the peripheral contour of the weight discs.