Abstract: Disclosed herein is a method for the production of reinforced thermoplastic and thermoadhesive polymers, used to make shaped reinforcing pieces for footwear in general, including sports shoes, these reinforced condensation polymers resulting from the polymerization of monomers such as lactones--specifically epsilon caprolactone, and condensable systems of two components, specifically polyisocyanates, polyols or polyolpolyesters--in the presence of reinforcing materials and, optionally, filling materials. The reinforced thermoplastic and thermoadhesive polymers are obtained in the form of sheets, from which the units or pieces are cut to a specified pattern, for example for the toecap, the heel piece or the inner sole.