A system is disclosed for the absorption of an impact, that system comprises a blow molded thermoplastic energy absorbing member. The blow molded thermoplastic energy absorbing member provides opposing first and second walls defining a hollow space; according to one embodiment, a plurality of fused and unfused recessed ribs integrally molded between the first and second walls. The fused recessed ribs have a fused recessed rib end. The fused recessed rib ends are integrally fused to either opposite recessed rib ends or the facing opposite wall at a welded surface such that the height of the recessed ribs from the first wall to the welded surface is about approximately 15.0 to 45.0 mm. The recessed ribs are, according to one embodiment, connected by a plurality of straight interlocking ribs.