Aerobic exercise training linked to enhanced brain function
Regular aerobic exercise may decrease the likelihood of developing Alzheimer's disease
February 3, 2020
Science Daily/IOS Press
Individuals at risk for Alzheimer's disease (AD) because of family history or genetic predisposition who engaged in six months of aerobic exercise training improved their brain glucose metabolism and higher-order thinking abilities (e.g., planning and mental flexibility) called executive function; these improvements occurred in conjunction with increased cardiorespiratory fitness. The results of this study are published in a special issue of Brain Plasticity devoted to Exercise and Cognition.
Drugs currently available to treat AD have limited therapeutic capacity. At a time when both the human and monetary costs of the disease are projected to rise dramatically in the coming decades, there is a critical need to provide individuals with readily-deployable strategies that can decrease the likelihood of acquiring the disease or slow its progression. Researchers therefore investigated whether exercise training in asymptomatic individuals harboring risk for AD improves markers associated with AD.
"This study is a significant step toward developing an exercise prescription that protects the brain against AD, even among people who were previously sedentary," explained lead investigator Ozioma C. Okonkwo, PhD, of the Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health.
The study investigated 23 cognitively normal, relatively young older adults with a family history or genetic risk for AD. All patients had a sedentary lifestyle. They underwent a battery of assessments, including cardiorespiratory fitness testing, measurement of daily physical activity, brain glucose metabolism imaging (a measure of neuronal health), and cognitive function tests.
Half of the participants were randomly assigned to receive information about maintaining an active lifestyle but no further intervention. The other half participated in a moderate intensity treadmill training program with a personal trainer, three times per week for 26 weeks.
Compared to the participants maintaining their usual level of physical activity, individuals assigned to the active training program improved their cardiorespiratory fitness, spent less time sedentary after the training program ended, and performed better on cognitive tests of executive functioning (but not episodic memory). Executive function, an aspect of cognition that is known to decline with the progression of AD, comprises the mental processes enabling individuals to plan, focus attention, remember instructions, and juggle multiple tasks successfully. The participants' improved cardiorespiratory fitness was associated with increased brain glucose metabolism in the posterior cingulate cortex, an area of the brain linked to AD.
"This research shows that a lifestyle behavior -- regular aerobic exercise -- can potentially enhance brain and cognitive functions that are particularly sensitive to the disease. The findings are especially relevant to individuals who are at a higher risk due to family history or genetic predisposition," noted Dr. Okonkwo. The lead author on the study, Max Gaitán, MEd, of the Wisconsin Alzheimer's Disease Research Center, University of Wisconsin School of Medicine and Public Health, remarked that "an important next step would be to conduct a larger, more definitive, study. If these findings are replicated, they would have a tremendous impact on quality of later life, providing individuals with more years of independent living, active engagement with loved ones, and building memories."
https://www.sciencedaily.com/releases/2020/02/200203104450.htm
Keep exercising: New study finds it's good for your brain's gray matter
January 2, 2020
Science Daily/Mayo Clinic
A study provides new evidence of an association between cardiorespiratory fitness and brain health, particularly in gray matter and total brain volume -- regions of the brain involved with cognitive decline and aging.
Cardiorespiratory exercise -- walking briskly, running, biking and just about any other exercise that gets your heart pumping -- is good for your body, but can it also slow cognitive changes in your brain?
A study in Mayo Clinic Proceedings from the German Center for Neurodegenerative Diseases provides new evidence of an association between cardiorespiratory fitness and brain health, particularly in gray matter and total brain volume -- regions of the brain involved with cognitive decline and aging.
Brain tissue is made up of gray matter, or cell bodies, and filaments, called white matter, that extend from the cells. The volume of gray matter appears to correlate with various skills and cognitive abilities. The researchers found that increases in peak oxygen uptake were strongly associated with increased gray matter volume.
The study involved 2,013 adults from two independent cohorts in northeastern Germany. Participants were examined in phases from 1997 through 2012. Cardiorespiratory fitness was measured using peak oxygen uptake and other standards while participants used an exercise bike. MRI brain data also were analyzed.
The results suggest cardiorespiratory exercise may contribute to improved brain health and decelerate a decline in gray matter. An editorial by three Mayo Clinic experts that accompanies the Mayo Clinic Proceedings study says the results are "encouraging, intriguing and contribute to the growing literature relating to exercise and brain health."
Ronald Petersen, M.D., Ph.D., a Mayo Clinic neurologist and first author of the editorial, says the most striking feature of the study is the measured effect of exercise on brain structures involved in cognition, rather than motor function. "This provides indirect evidence that aerobic exercise can have a positive impact on cognitive function in addition to physical conditioning," he says. "Another important feature of the study is that these results may apply to older adults, as well. There is good evidence for the value of exercise in midlife, but it is encouraging that there can be positive effects on the brain in later life as well."
Dr. Petersen is the Cora Kanow Professor of Alzheimer's Disease Research and the Chester and Debbie Cadieux Director of the Mayo Clinic Alzheimer's Disease Research Center.
The study's finding of higher gray matter volume associated with cardiorespiratory exercise are in brain regions clinically relevant for cognitive changes in aging, including some involved in Alzheimer's disease. The editorial calls those associations interesting but cautions against concluding that cardiorespiratory fitness correlations would affect Alzheimer's disease.
"This is another piece of the puzzle showing physical activity and physical fitness is protective against aging-related cognitive decline," says Michael Joyner, M.D., a Mayo Clinic anesthesiologist and physiologist, and editorial co-author. "There's already good epidemiological evidence for this, as well as emerging data showing that physical activity and fitness are associated with improved brain blood vessel function. This paper is important because of the volumetric data showing an effect on brain structure."
Dr. Joyner is the Frank R. and Shari Caywood Professor at Mayo Clinic.
Long-term studies on the relationship between exercise and brain health are needed, which will be costly and logistically challenging to produce. "Nevertheless, these data are encouraging," says Clifford Jack Jr., M.D., a Mayo Clinic neuroradiologist and co-author of the editorial. "The findings regarding cardiorespiratory fitness and certain brain structures are unique."
Dr. Jack is the Alexander Family Professor of Alzheimer's Disease Research.
According to Mayo Clinic experts, moderate and regular exercise -- about 150 minutes per week -- is recommended. Good cardiorespiratory fitness also involves:
Not smoking
Following healthy eating habits
Losing weight or maintaining a healthy weight level
Managing blood pressure and avoiding hypertension
Controlling cholesterol levels
Reducing blood sugar, which over time can damage your heart and other organs
University Medicine Greifswald, Germany, also was part of the research project. Katharina Wittfeld, Ph.D., a researcher at the German Center for Neurodegenerative Disease, is first author.
https://www.sciencedaily.com/releases/2020/01/200102094314.htm