Abstract: A sleep support surface includes a mattress having at least two bladders located adjacent a foot end. The bladders each have a predetermined, adjustable internal pressure. The pressure in at least one of the bladders is selectively and independently reduced to provide pressure relief on the heels of the patient lying on the mattress. The pressure in a bladder located toward the head end of the mattress and adjacent the at least one bladder is increased. This pressure increase advantageously provides the lifting force under the calves of the patient to reduce further pressure on the patient's heels. A visual indication of the location each of the at least two bladders in the mattress is provided to facilitate selection of the at least one bladder in which to reduce pressure during the pressure reducing step, thereby providing pressure relief on the heels of the patient lying on the mattress.