Exercise May Help the Aging Brain ‘Take Out the Trash’

Regular exercise may do more than strengthen the body. New research from Victoria University adds to evidence that physical activity could also play an important role in protecting the brain from age-related decline, including dementia and Alzheimer’s disease.

The study, led by Dr. James Broatch, examined how exercise may influence the glymphatic system, a brain waste clearance pathway that is especially active during sleep. This system helps maintain and regulate brain health, and its role becomes increasingly important with age.

The benefits of exercise for healthy aging are already well established, but researchers are still working to understand exactly how physical activity protects the brain. Finding those mechanisms is particularly important because more than 10 million people worldwide are diagnosed with dementia each year, and there is currently no cure.

The Glymphatic System: A Key Player in Brain Waste Clearance

The glymphatic system is a complex network of fluid pathways that helps to clear waste and toxins from the brain. During sleep, the glymphatic system is more active, allowing it to efficiently remove waste products that can accumulate and cause damage to brain cells.

Dr. Broatch and his team reviewed existing studies of the glymphatic system in both animals and humans. They found that exercise can improve several physiological processes involved in regulating glymphatic function, including reducing blood pressure and vascular stiffness, improving the activation of neurons in the brain, reducing inflammation in the brain, lowering resting norepinephrine, and improving sleep.

Exercise may also increase the quality of deep sleep and enhance slow wave activity associated with brain waste clearance. By improving these processes, exercise may help to support the glymphatic system and reduce the accumulation of waste products in the brain.

The Connection Between Exercise and Brain Health

Dr. Broatch said the connection between exercise and brain protection could provide an important clue as scientists search for evidence-based forms of physical activity that may help limit brain deterioration with age.