A system for preventing pressure ulcers, where the system includes one or more actuators, one or more bearings assemblies each including a multiplicity of movable bearings and optionally an enveloping strip operatively associated with the actuator. The bearings can be rotated to allow shifting locations of the bearings in respect to a part of the patient's body laid thereover for changing pressured touch points between the part of the patient's body and the bearings over time for preventing development of pressure ulcers. This is done by moving the patient's body caused by the rotation of the bearings.