Clinical Question

Does aerobic physical activity improve cognitive function in older adults?

Evidence-Based Answer

Physical activity improves cardiovascular fitness in persons older than 55 years. Cognitive speed and auditory and visual attention are increased in healthy older adults who exercise.

Practice Pointers

There is a measurable decline in cognitive function that begins at 50 years of age. Cardiovascular fitness may improve cerebral blood flow, oxygen extraction, or glucose metabolism, which has been hypothesized to improve cognitive function.

The authors of this review found 11 studies of adults older than 55 years without cognitive impairments. Studies were generally good quality, but there is a risk of bias because blinding was not practical. Participants in the intervention groups engaged in aerobic exercise. Control groups had no program, or had programs limited to strength, balance, or social or mental activities. Aerobic exercise had a significant effect on cognitive speed, visual and auditory speed, and motor function, but had no significant effect on most other cognitive functions. The maximum volume of oxygen utilization improved in the aerobic exercise group by an average of 16 percent compared with that of the control group, which improved by an average of 2 percent.

Although there is an association between improved cardiovascular fitness and improved cognitive function, it is not clear if aerobic exercise causes the improvements or whether other types of physical exercise might result in the same benefit.

Recommended levels of exercise for older adults are substantial. According to the American College of Sports Medicine and American Heart Association, older adults should engage in aerobic physical activity intense enough to noticably increase heart rate and breathing for a minimum of 30 minutes on five days each week.¹ Alternatively, they can engage in aerobic activity that causes large increases of heart rate and breathing for a minimum of 20 minutes on three days each week. Also, twice per week, older adults should engage in activities to maintain or increase muscular strength, endurance, and flexibility.¹