An anti-submarining seat cushion for a vehicle includes a main body constructed of an anisotropic material. The anisotropic material includes a primary material including a primary stiffness and a plurality of inserts that are dispersed throughout the primary material. The plurality of inserts exert an axial compressive force in response to the main body of the anti-submarining seat cushion experiencing a submarining load, where the axial compressive force is exerted in a direction that opposes the submarining load to increase an overall stiffness of the main body in a direction that aligns with the submarining load.