one subject of the present invention is a composition that combines at least one polyamide having at least one mxd entity , mxd denoting meta - xylylenediamine or a mixture of meta - xylylenediamine and of para - xylylenediamine , with a bioresourced reinforcement . the invention also relates to the conversion of these compositions , by injection moulding or extrusion , into objects that have good mechanical properties , said objects corresponding to technical application specifications such as may be found , for example , in the automotive industry , construction , sport and in electrical or electronic fields .