Sedentary behavior, characterized by excess sitting time during waking hours, is detrimental to health and increases cardiometabolic disease (e.g., type 2 diabetes) risk, independent of moderate-to-vigorous physical activity. The mechanisms that mediate this are unknown and there are no evidence-based methods known for effectively intervening on sedentary behavior. The consequences of prolonged sitting time are of particular interest in older adults as sedentary behavior and cardiometabolic disease risk both increase with aging and moderate-to-vigorous physical activity may not be feasible. The investigators propose pilot and feasibility testing of interventions for sedentary older adults that are designed to interrupt prolonged sitting time. Interrupting sitting time through sit-to-stand transitions, and standing and walking breaks increases muscle use and blood flow in the lower parts of the body. Thus, the investigators believe that frequent sit-to-stand interruptions of sitting time are the most efficacious sedentary behavior interventions, compared to simply reducing sitting time or less frequent walking breaks, for improving health outcomes and healthy aging. The investigators hypothesize that frequent sit-to-stands during a 5-hour sitting period will result in health benefits that can be observed with a simple 2-minute standing interruption, and that this will be associated with improvements in metabolism and endothelial function. This pilot, 10-participant study will 1) generate preliminary data for a revised Program Project Grant application to the National Institute of Aging (NIA) that focuses on postmenopausal women, the fastest growing aged population with high life-time risk of cardiometabolic risk. This pilot study will inform sitting interruption modality design for two projects in the investigators' Program Project Grant application: "Project 1: Sedentary Behavior Interrupted: A randomized crossover treatment trial of acute effects on biomarkers of healthy aging in the laboratory (86 participants)" and "Project 2: Sedentary Behavior Interrupted: A randomized trial of 6 month effects on biomarkers of healthy aging and physical functioning in the real world (660 participants)." The current design of this pilot study is enhanced by and responsive to feedback from our initial NIA submission. This pilot study will increase our knowledge about how sedentary behavior and sitting interruption interventions influence healthy aging in postmenopausal women.