Abstract: The invention relates to methods of treating a subject having a muscle disorder by identifying a subject having a muscle disorder in need of treatment; injecting human myogenic precursor cells in an amount capable of forming mature muscle tissue into a portion of a limb of the subject; subjecting a nerve of the limb to therapeutic stimulation configured to enhance engraftment of the human myogenic precursor cells; and creating a graft of the human myogenic precursor cells to promote generation of mature muscle tissue, wherein the generation of mature muscle tissue improves muscle function. Preferably, the subject is a mammal, such as a human or a non-human mammal. In some embodiments, the non-human mammal is immunocompromised and the limb is irradiated. The engraftment can be promoted by a means other than therapeutic electrical stimulation (preferably intermittent neuromuscular electrical stimulation), for example by exercise.