Abstract: An exercising machine for bodybuilders which facilitates the safe and proper performance of various lower body exercises such as squats and lunges. The machine safely facilitates free, natural movements in two planes to promote muscle growth and bone and tendon strength. The machine is ideally suited to use as a rehabilitation device. A rigid steel frame of generally rectangular configuration rests upon a resilient, skid-resistant mat. The frame comprises rigid, spaced apart side rails and parallel cross members. A carriage assembly is slidably disposed upon the rails for movement along the frame. The carriage assembly includes a pair of rigid, parallel arches which extend vertically from roller assemblies associated with the frame rails. The roller assemblies comprise twin-bearing pillow blocks which permit the carriage to roll securely along the rails. A weight bar system extending between carriage sides may be loaded as desired by the bodybuilder.