An exercise apparatus includes a frame with a pair of vertical guides. A carriage is slidably carried on each of the guides. Each of the carriages has a locking mechanism to lock the carriage at a selected vertical position and a release to disengage the locking mechanism. A horizontal exercise bar is slidably carried on guide rods. First and second cables are coupled to a selectable exercise resistance, each of the cables having an end selectively coupled to either the respective carriage or to a respective bracket at the end of the exercise bar. Secondary brackets on the exercise bar are configured to engage respective ones of the carriage releases and grab the carriage so as to selectively engage and disengage the locking mechanisms upon axial rotation of the exercise bar and raise and lower the carriages with the exercise bar.