A weight selection and adjustment system for a selectorized dumbbell comprises a stand that holds a pair of selectorized dumbbells. The stand has an electric motor that is selectively energized by a controller for substantially simultaneously adjusting the weight of both dumbbells. The controller is responsive to a weight selection made by a user through a data entry device. The system can also be used with a single dumbbell placed on the stand. Alternatively, the electric motor can be mounted on the handle of a selectorized dumbbell to allow weight adjustment operations to be made without placing the selectorized dumbbell on a stand. In this embodiment, the data entry device and controller can also be carried on the handle of each selectorized dumbbell.