Sedentary behavior (SB) is prevalent in workplaces, putting office workers at an increased risk of severe health problems. To help designers and researchers gain a better understanding of office workers’ contextual concerns for physical inactivity (reducing SB and enhancing physical activity (PA)), we have proposed a conceptual framework ACTIVE4. This framework advises designers and researchers to consider four key factors that influence office workers’ physical inactivity: active mind, active behavior, active support, and active environment. We conducted three workshops (N=28 design students) to evaluate the framework. The participants found ACTIVE4 helpful in guiding them towards a more systematic understanding of the environmental influences and office workers’ personal needs for reducing physical inactivity. In future work, we will optimize the ACTIVE4 framework’s learning curve as suggested by participants and conduct an expert study to further discuss design opportunities and requirements for the ACTIVE4-related vitality toolkit.