This study of a monkey model of sarcopenia is still in the early stages. Vastus lateralis muscle biopsies have been collected from all of the squirrel monkeys. The samples were frozen for processing. Biochemical and histological analysis of the muscle sample are still underway and include mysoin ATPase activity for determination of muscle fiber type, proportions, and cross-sectional area. Preliminary data indicate an age-related decline in type II fibers, consistent with other species. A grip strength apparatus is in the final stages of development and monkeys will be tested for changes in muscle function as well. Once the biochemical and histological characterization of the aging muscle is complete, the intervention protocol will be determined to target those pathways identified during characterization as most susceptible to aging changes.