BACKGROUND: Regular physical activity plays an important role in the amelioration of several mental health disorders; however, its relationship with burnout has not yet been clarified. OBJECTIVE: To determine the association between achievement of national physical activity guidelines and burnout in internal medicine resident physicians. METHODS: A Web-based survey of internal medicine resident physicians at the University of Minnesota and Hennepin County Medical Center was conducted from September to October 2012. Survey measures included the Maslach Burnout Inventory-Human Services Survey and the International Physical Activity Questionnaire. RESULTS: Of 149 eligible residents, 76 (51.0%) completed surveys, which were used in the analysis. Burnout prevalence, determined by the Maslach Burnout Inventory, was 53.9% (41 of 76). Prevalence of failure to achieve US Department of Health and Human Services physical activity guidelines was 40.8% (31 of 76), and 78.9% (60 of 76) of residents reported that their level of physical activity has decreased since they began medical training. Residents who were able to meet physical activity guidelines were less likely to be burned out than their fellow residents (OR, 0.38, 95% CI 0.147-0.99). CONCLUSIONS: Among internal medicine resident physicians, achievement of national physical activity guidelines appears to be inversely associated with burnout. Given the high national prevalence of burnout and inactivity, additional investigation of this relationship appears warranted.