Abstract: We describe herein methods for applying physical stimuli to cells, including mesenchymal stem cells, in culture or in vivo. These methods can be applied in, and are expected to benefit subjects in, a great variety of circumstances that arise in the context of, for example, traumatic injury (including that induced by surgical procedures), wound healing (of the skin and other tissues), cancer therapies (e.g., chemotherapy or radiation therapy), tissue transplantation (e.g., bone marrow transplantation), and aging. More generally, the present methods apply where patients would benefit from an increase in the number of cells (e.g., stem cells) within a given tissue and, ex vivo, where it is desirable to increase the proliferation of cells (e.g., stem cells) for scientific study, inclusion in devices bearing cells (e.g., polymer or hydrogel-based implants), and administration to patients.