This study involves designing/ implementing a patient-centered, individually-focused physical activity (PA) intervention designed for integration into clinical care. We will recruit adult patients (aged 21-70; n=80) from the general internal medicine practice of a local health system who are not meeting the US aerobic activity goal of 150 minutes/ week of at least moderate intensity PA and who can safely increase PA without supervision. As low PA levels have been associated with numerous poor health outcomes, the primary intervention goal will be achievement of the US PA goal. A secondary goal will be to reduce sedentary behavior (SED), which is related to poor health outcomes (independent of PA achievement). Intervention materials will be developed using a patient/provider centered approach and delivered weekly over 3 months via an existing online platform with participants self-tracking behavior outcomes will be examined using a three month wait-listed control design in which all participants will eventually receive the intervention.