Abstract: Certain disclosed oligomers induce exon skipping during processing of myostatin pre-mRNA. The oligomers may be in a vector or encoded by the vector. The vector is used for inducing exon skipping during processing of myostatin pre-mRNA. A therapeutically effective amount of the oligomer may be administered to a subject patient such that exon skipping during processing of myostatin pre-mRNA is induced. The administration to a subject may be used in order to increase or maintain muscle mass, or slowing degeneration of muscle mass in the subject. The administration to a subject may ameliorate muscle wasting conditions, such as muscular dystrophy.