In this pilot study, the investigators focus on three different types of prolonged sitting interruptions as variables. Studies have shown that frequent breaks in sitting may reduce risk for cardiometabolic disease. In older adults, the investigators anticipate that frequent sit-to-stand transitions will impact metabolic, inflammatory and other biomarkers, in particular those related to mitochondrial and endothelial function. A key limitation of previous sedentary intervention studies is that they have not impacted frequency of sit-to-stand transitions; rather, they decreased total sitting and increased standing time. Further, previous sedentary intervention studies have not directly compared frequent sit-to-stand transition interruptions with other interruption modalities associated with less frequent sit-to-stand transitions, for example, reduced overall sitting time (standing more) or with occasional walking breaks. The investigators propose to test these sedentary behavior interruptions modalities to disrupt prolonged sitting and explore mitochondrial- and endothelial function-based mechanisms of action. Biologic theories suggest that interrupting sitting via sit-to-stand muscle contraction and increased blood flow to extremities is key to improving in healthy aging outcomes.