Guiding research and practice: a conceptual model for aerobic exercise training in Alzheimer's disease.

Alzheimer's disease is a global, epidemic problem affecting mainly older adults with tremendous social and financial burdens. Older adults with Alzheimer's disease showed reduced physical activity and cognitive changes that are probably amenable to aerobic exercise training. The purpose of this paper is to develop a conceptual model to guide future aerobic exercise research and practice by synthesizing the current state of the science on aerobic exercise training in older adults with AD. The literature review found 12 qualified studies that met the eligibility criteria for inclusion in this review and revealed six constructs (aerobic exercise training, physical fitness, physical performance, activities of daily living limitations, cognition, and psychological and behavioral symptoms), which composed the Functional Impact of aerobic exercise Training in Alzheimer's disease (FIT-AD) model. The state of science on each construct in older adults with Alzheimer's disease is reviewed and summarized. The emerging evidence suggests that aerobic exercise training might positively impacts all five other constructs. The implications of the FIT-AD model for future research and practice are discussed highlighted.