Goal Setting to Promote Physical Activity Adherence in Midlife Adults

Inclusion Criteria: * Aged 45 to 65 years * BMI between 30 kg/m2 to 50 kg/m2 * Participants must weigh a minimum of 110 pounds * Engaging in 60 minutes or less of self-reported moderate-to-vigorous physical activity at screening (based on Exercise Vital Sign Questionnaire) * Self-reported ownership of a smartphone with an iOS or Android operating system (necessary for participants to track their activity using a Fitbit activity monitor) Exclusion Criteria: * Endorsing an item on the Physical Activity Readiness Questionnaire (PAR-Q), unless a physician's note is provided * Resting blood pressure greater than 200/110 mmHG as assessed at the baseline study assessment (unless a physician's note is provided) * Pregnant or planning to become pregnant in next 8-months (Phase 1) or 12 months (Phase 2) * Plans to relocate out of metropolitan Phoenix, Arizona area in the next 8-months (Phase 1) or 12 months (Phase 2) * Participation in another physical activity, nutrition or weight loss program at time of screening or at any time during the intervention * Individuals with mild cognitive impairment (MCI), as determined by either a self-report of receiving a diagnosis of MCI from a health care provider or as assessed by the Montreal Cognitive Assessment (MoCA) at the study orientation session. A score \< 26 is an exclusion criterion for US born participants. A score of \<23 is an exclusion for participants born outside of the US who completed their high school education in a country where English is not the primary language. * Being previously prescribed one of the 5 approved Alzheimer's medications, including: Donepezil (Aricept), Rivastigmine (Exelon), Galantamine (Razadyne), Memantine (Namenda), Memantine + Donepezil (Namzaric) * Score of 16 or higher on the Center for Epidemiological Studies-Depression Scale (CES-D) * Self-reported current diagnosis of major depression * Currently taking 2 or more ant-depression drugs * History of stroke * Incarcerated individuals (i.e., Prisoners)