The present invention includes curable compositions adapted to coat substrates. In one embodiment, the composition includes an antioxidant selected from terpene materials; vitamin materials different from the terpene materials; and combinations thereof in an amount of about 0.00001 weight percent to about 5 weight percent based upon the weight of the substrate. In another embodiment, the composition includes (a) an antioxidant selected from terpene materials; vitamin materials different from the terpene materials; and combinations thereof in an amount effective to inhibit oxidation of the composition; and (b) a film-forming material capable of forming a substantially uniform continuous coating on the substrate. Also included are substrates and sized glass fibers coated with such compositions and fabrics woven from such coated fibers. Other aspects of the present invention include methods for inhibiting the oxidation of a coating composition adapted to coat substrates.