Aerobic exercise effects upon cognition in Alzheimer's Disease: A systematic review of randomized controlled trials.

BACKGROUND: Previous reviews and meta-analysis have shown that physical activity has positive effects on cognition in healthy elderly as well as in patients with Mild Cognitive Impairment, even if with a minor effect whereas less is known about the effectiveness of aerobic exercise in patients with Alzheimer's Disease (AD). OBJECTIVES: The aim of the present study was to systematically review the evidence from randomized controlled trials (RCTs) designed to evaluate aerobic exercise effects upon cognition in AD patients. METHODS: PubMed, Cochrane, Web of Science and DARE databases were analytically searched for RCTs including aerobic exercise interventions for AD patients. RESULTS: There is scarce evidence that aerobic exercise improves cognition in AD patients. Overall, the included studies reported only positive effects for patients'global cognition after intervention, mainly due to a lack of accurate neuropsychological assessment of each cognitive domain. Whether the bene ts of exercise are evident in all stages of AD pathology remain also uncertain. CONCLUSIONS: Standardized protocols, larger and more rigorous RCTs with long-term follow-ups may provide better insight into the effects of aerobic exercise on cognitive deterioration characterizing people with AD.