A barbell comprises a bar with a receptacle at each end of the bar. The receptacle is configured to receive a selectorized dumbbell therein. The dumbbell is placed into the receptacle in a first loaded condition with a plurality of weights being coupled to the dumbbell. After such placement, the dumbbell can be adjusted to a second loaded condition in which the dumbbell carries fewer weights than in the first loaded condition. The dumbbell is then removed from the receptacle while in the second loaded condition to thereby leave behind at least one weight in the receptacle. Alternatively, the dumbbell in its first loaded condition can simply be left in its entirety in the receptacle. A lock can be provided on the receptacle to help retain within the receptacle either the dumbbell or the weights left behind in the receptacle. Thus, at least portions of selectorized dumbbells provide exercise mass for the barbell.