A process for increasing lean body mass in a mammalian subject is provided that includes administering to the subject a purified quantity of maslinic acid, oleanolic acid, or a combination thereof. The administration can be orally and benefits from ingestion of an amino acid source such as dietary protein, oligopeptides, or amino acids. Administration within 2 hours of muscle-degrading exercise or on a daily basis for a period of time increases lean body mass.
