The feasibility of exercise to improve cerebrovascular health in older adults.

Research Objectives: To investigate the feasibility of exercise in aging targeted to improve cardiovascular fitness, basal cerebral perfusion, cerebrovascular reactivity (CVR) and improve cognitive-executive performance. Comorbidities associated with aging continue to rise. According to the Alzheimer’s Association, one in three adults over the age of 65 will die with Alzheimer’s disease (AD) or a related dementia. Intertwined with aging-related pathologies are physiological changes in cardio and cerebrovascular function.

Design: Pre/post design with a 12 week, three times a week intervention

Setting: Exercise intervention research laboratory

Participants: Twenty older adults randomly assigned to one of two interventions

Interventions: 12 weeks of 3 times weekly exercise to one of two groups; 1) progressive, high intensity aerobic training (Spin) at or above 50% of heart rate reserve or 2) a contact controlled, duration matched, non-aerobic training condition consisting of range of motion and balance exercise at less than 50% of heart rate reserve.

Main Outcome Measures: Adherence to exercise and all pre/post evaluations including: Arterial spin labeling (ASL) to measure cerebral blood flow;
Cerebrovascular reactivity (CVR) assessed using 5% CO2 challenge while continuously acquiring MR images;
Standard battery of cognitive-executive to measure executive functions including inhibition, working memory and verbal fluency; and a cardiovascular fitness assessment (VO2).

Results: Over the recruitment and intervention period twenty participants were randomized (mean age 73.2 ± 6.5; age range 65-79 years; 20% female). Randomized participants that completed the intervention (n=19) attended 92% of the exercise classes and completed all pre and post brain imaging and behavioral assessments.

Conclusions: The present study shows feasibility of recruitment and consent rate, adherence to the physical activity interventions and assessments as well as study retention. These data indicate that interventions to further evaluate the effects of aerobic exercise on the neural substrates of improved cognition demonstrated with exercise in aging are feasible.

Author(s) Disclosures: None