As patients lose cognitive function, they lose autonomy and increasingly use fiscal, social, and medical resources. Healthcare costs for Americans older than age 65 years are three to five times higher than for the remaining population, and dementia is the third most costly disease in the United States. Interventions that promote successful aging can help patients and reduce the financial, workforce, and treatment resource burdens on the population. Because a relationship between physical activity, particularly aerobic exercise, and cognitive decline has been established, physical activity interventions may prove practical, affordable, and effective. Attention to empiric research and knowledge of evidence-based strategies for prescribing physical activity are critical for PAs to embrace.