A guide rail (12) of a linear guide unit (10) is provided with at least one running rail (16), which has at least two races (16a) that have different load transmission directions. According to the present invention, the running rail (16) is attached to the guide rail (12) by means of roller insertion; in the surface sections (12a) associated with the races (16a) of the running rail (16), the guide rail (12) is provided with a plurality supporting ribs (12a1); and the supporting ribs (12a1) associated with one and the same race (16a) are aligned essentially parallel to the load transmission direction (B) of this race (16a). In addition or alternatively, in a section (12d) that is not intrinsically deformed by the roller insertion of the at least one running rail (16), the guide rail (12) has at least one additional rolled section. The present invention also relates to a method for manufacturing guide rails of this kind (12).