Health trends come and go, but one medical truism has proven remarkably durable: if regular exercise were a drug, nearly every doctor would prescribe it. Exercise has the potential to stave off heart disease, diabetes, and a range of other ailments. Staying physically fit can help keep the mind sharp as well.
As a professor of psychology, neuroscience and engineering, I’ve spent much of my career studying the links between physical and cognitive health. While most people are probably aware that there is a mutually impactful relationship between our bodies and our minds, few realize just how consistent physical activity can change the brain’s structure and function. Aerobic exercise expands the volume of the hippocampus and prefrontal cortex, and can alter connections between the brain’s various networks that support memory and decision making.
These shifts in the brain’s properties can have important cognitive benefits. Exercise leads to molecular and cellular changes that support improvements in cognition. Regular exercise has been shown to improve executive functioning, a type of cognition that refers to the ability to plan, multitask, self-regulate, and manage complex tasks, as well as harder-to-define aspects of functioning, like dealing with ambiguity.
Three hours of light to moderate aerobic exercise weekly appears to have beneficial effects on memory, attention, and decision making.
The benefits of exercise can be seen quickly. Research has demonstrated that three hours of light exercise weekly can produce improvements in executive function within just six months. Those three weekly hours do not have to be at a high level of intensity. Type of aerobic exercise seems to be less important than simply raising your heart rate and getting your blood pumping.
Studies have suggested that periods of consistent physical activity early in life can pay off even decades later. We recently conducted a study comparing the brain of the champion track and field athlete Olga Kotelko, who competed into her 90s, to various other research participants of older age. The structure of Kotelko’s brain was often markedly different than many of the study participants. Connectivity of Kotelko’s hemispheres (via the corpus callosum) was more robust than some of the 60-year-old participants in the study. While such a study is not able to establish causation between particular behaviors and cognitive ability, as scientists would have to track a Kotelko-level athlete for her whole life in order to determine causality, it provides a basis for further scientific inquiry and hint at a broader relationship between brain health and exercise.
The connection between exercise and executive control appears to be consistent across age groups, although there is much that researchers still do not know. Next year, I will be one of the researchers running one of the largest and most comprehensive exercise studies ever: A multi-site project involving 650 research participants spread between the University of Pittsburgh, Northeastern University, and the University of Kansas. This study will enable us to examine exercise effects on cognition that are potentially influenced by genetic factors, age, gender, occupation, and other important variables. This study will also include brain scans before and after the study to examine structural and functional brain change over the course of the study. The project could produce results which could help doctors recommend exercise regimens for specific patient demographics. Studies like these will help us determine whether there are different effects of exercise for different people, which might allow for personalization of exercise interventions.
The current research is already good news for one group: older adults. The growing body of research demonstrating the benefits of exercise and physical health on cognition shows us that the brain can improve as people age. Three hours of light to moderate aerobic exercise weekly appears to have beneficial effects on memory, attention, and decision making. We used to think that there were little or few options for cognitive improvement as we age, and we are seeing that this is simply not the case. The health of the brain can be improved at any age so, let’s get moving!
This piece is part of a special brain health initiative curated by Dr. Ali Rezai, Director of Ohio State University Wexner Medical Center’s Stanley D. and Joan H. Ross Center for Brain Health and Performance. For more, visit The Huffington Post’s Brain Health page.