The invention provides methods for muscle repair or regeneration comprising administering therapeutically effective amounts of RAR agonists or stem cells that are pretreated with contact with a RAR agonist to a subject at a site of muscle damage. Additionally, the invention provides compositions comprising RAR agonist treated stem cells and methods of use of said cells for muscle repair or regeneration. In one embodiment, the stem cells are mesenchymal stem cells. In one embodiment, the RAR agonist is an RARγ agonist. In one embodiment, administration of the RAR agonist is begun during a period of increased endogenous retinoid signaling in the subject resulting from incurrence of the damaged muscle tissue.