The present invention is based in part upon the discovery that the use of pyruvate in enteral formulations, in combination with an anabolic protein composition, produces a synergistic effect in increasing the lean body mass or muscle tissue of a mammal consuming same. The present invention also provides a method for enhanced endurance of athletes. The present invention relates generally to a composition for enhancing the protein concentration or muscle mass of a mammal and a method for enhancing the protein concentration or muscle mass in a mammal. More specifically, the present invention relates to a composition which comprises pyruvate and/or derivatives of pyruvate and an anabolic protein composition. The method of the present invention comprises administering to a mammal in need of enhancing its protein concentration or muscle mass, a composition comprising pyruvate and an anabolic protein composition. The pyruvate/anabolic protein composition can take the form of powders, liquids, pills, capsules, tablets, food additives, candies or confections.