Exercise and Cognitive Function
February 2nd, 2009
Being physically fit helps the brain function at the top of its game. A new study finds that physical activity benefits blood flow in the brain which improves cognitive abilities.
“Being sedentary is now considered a risk factor for stroke and dementia,” says Marc Poulin, Ph.D., lead author and scientist in the Faculties of Medicine and Kinesiology at the University of Calgary. “This study proves for the first time that people who are fit have better blood flow to their brain. Our findings also show that better blood flow translates into improved cognition.” The report appears in the current edition of the journal Neurobiology of Aging.
The study compared two groups of women whose average age was 65 years old. From a random sample of 42 women living in Calgary, the study observed women who took part in regular aerobic activity and another group of women who were inactive. Poulin’s team recorded and measured the women’s cardiovascular health, resting brain blood flow and the reserve capacity of blood vessels in the brain, as well as cognitive functions.
The scientists found that compared to the inactive group, the active group had lower (10 percent) resting and exercising arterial blood pressure, higher (5 percent) vascular responses in the brain during exercise and higher (10 percent) cognitive function scores.
Previous studies have found that as people age, there is a progressive decline in blood flow to the brain. “The take home message from our research is that basic fitness - something as simple as getting out for a walk every day - is critical to staying mentally sharp and remaining healthy as we age,” says Poulin, a member of the Department of Physiology & Biophysics and the Hotchkiss Brain Institute.
Each participant did an interview and questionnaire enumerating the hours they spent on recreational, volunteer and household activities. Poulin’s team then converted those activities into units of energy expenditure.
Participants also did a bike test to assess their fitness level, in which Poulin’s team measured oxygen uptake, carbon dioxide production, heart rate, blood pressure, and the level of oxygen in the blood. The research team then measured the respiration of the participants in a resting state, and then again while riding a bike.
The final phase of the study was a comprehensive 2.5 hour test measuring the participants’ overall cognitive function including assessment of several cognitive domains: Verbal knowledge, spatial reasoning, memory, processing speed, multi-tasking, initiation, and planning.
“This study provides compelling evidence that aerobic fitness contributes to the maintenance of healthy brain function throughout the aging process,” says Poulin. “Results from our study provide a strong scientific basis for future studies to examine how exercise improves cognition in older adults. The implications are considerable given the aging population and age-related cerebrovascular diseases such as Alzheimer’s disease and stroke.”
For more information about exercise and nutrition for health and wellness call Dr. Richard Browne, Acupuncture Physician, at (305) 595-9500. Jan. 27.