Abstract: A fluid-containing mattress for reducing rapid fluid motion in the mattress is provided in one direction while permitting fluid flow in the opposite direction. The mattress comprises upper and lower sheets connected together in superposed relation. A number of thin, elongated members or strips are internally attached to the upper and lower sheets within the mattress. A strip attached to the upper sheet and a strip attached to the lower sheet are intermittently joined together at their longitudinal edge portions to form a one-way strip valve. A plurality of these strip valves are formed within the mattress to selectively direct fluid motion. Passages are also provided to bypass these strip valves so that the fluid eventually returns to all segments of the mattress and a uniform displacement of fluid is maintained in the mattress.