An adjustable device for supporting a load includes a belt for fastening about a user's waist. A rod includes two rigid elements. One of the elements is longitudinally slidable relative to the other element so as to adjust a length of the rod. A lower end of the rod is attachable to the belt and an upper section of the rod is attachable to a shoulder harness that is placeable on the user's shoulders for carrying the load. A control is operable by the user when carrying the load to unlock a locking mechanism that, when locked, fixes the length of the rod. When the control is operated concurrently with movement of the user's shoulders relative to the user's waist, the length of the rod is changed to adjust a distribution of a weight of the load between the user's shoulders and waist.