This invention is of a method and equipment for reducing stress concentrations in a body supported in a horizontal or any reclining position up to and including a fully seated position. The stress reduction is accomplished by means of specially designed or arranged cushioning material contained inside a membrane or bladder wherein the pressure of a fluid inside the membrane can be controlled as a means of varying the cushioning effect (compressibility) of the material inside and holding the cushioning material in specific places to reduce fight-back of the material over supporting edges that may otherwise create undesirable shear on the supported body tissue.