- Existing Studies show that exercise helps protect brain cells through mechanisms that researchers don’t yet fully understand.
- Researchers know that exercise increases brain glucose metabolism, which correlates with improved brain function.
- Studies show that exercise affects insulin resistance and has a complex relationship with body mass index (BMI) levels.
- A new study suggests that exercise plays a role in maintaining insulin levels and BMI, which may help stave off dementia by protecting gray matter volume in the brain.
A new study investigates the mechanisms involved in the relationship between exercise and brain health.
Previous research had shown that increased gray matter volume may help protect against dementia by improving brain function.
The new study shows that insulin resistance and BMI mediate the relationship between larger and smaller brain gray matter volumes (the part of the brain involved in information processing).
The research is published in the April 2022 online edition of NeurologyThe medical journal of the American Academy of Neurology.
The corresponding author of the study was Dr. Geraldine Poisnelof the Inserm Regional Research Center, in Caen, Normandy, France.
The study involved 134 people with an average age of 69 who had no memory problems. Participants completed a physical activity survey covering the past 12 months. Brain scans were also done to measure glucose metabolism Y brain volume.
Glucose metabolism in the brain. provides fuel for the brain by generating adenosine 5′-triphosphate (atp) — a key molecule for maintaining the health of neurons and other cells. ATP is also key to generating neurotransmitters. Reduced glucose metabolism in the brain can be seen in people with dementia.
Gray matter development peaks at age 23 years. It begins to decrease later in some areas of the brain, but the gray matter density increases. From an evolutionary perspective, the increased processing capacity of the human brain and its growth due to this increase in density.
In some studiesLarger total brain volume, as estimated by magnetic resonance imaging (MRI), has a weak correlation with higher intelligence in men and a very weak correlation in women with the ability to perform well on intelligence tests.
In contrast, brain tissue deterioration and volume loss contribute significantly to lower cognitive ability later in life.
In the new study, the researchers included 134 people with an average age of 69 who had no memory problems. Participants completed a physical activity survey covering the past 12 months. Brain scans were also done to measure glucose metabolism Y brain volume.
In the new study, researchers collected information on cardiovascular risk factors, including BMI Y insulin levels, as well as cholesterol, blood pressure and other factors.
The researchers examined the relationship between insulin and cardiovascular disease. Insulin-induced metabolic abnormalities increase the risk of cardiovascular complications, which in turn affect brain function.
The researchers found that insulin levels and BMI did not affect glucose metabolism in the brain.
The investigation showed that the amount of amyloid plaque in the brain that contributes to Alzheimer disease was not affected by exercise.
Today’s medical news contacted Dr Raeanne Mooreadjunct associate professor of psychiatry at UCSD in La Jolla, CA.
Dr. Moore, who was not involved in the study, was asked about the results of the study. she shared with MNT:
“This study adds to the growing body of research on the positive benefits of staying active for brain health, especially as we age.”
“[T]there is an urgent need to identify markers of cognitive decline,” added Dr. Moore. “Decreased insulin levels and weight loss are modifiable factors that can be improved with a healthy diet and exercise.”
He added: “It was not surprising that increased physical activity was not associated with the amount of amyloid plaque people had in their brains. There is increasing evidence that vascular risk factors in cognitive function are mediated by the amount of tau pathology in the brain and not an amyloid load.”
MNT also spoke with Dr Sheldon Zablow, assistant professor of medicine at the University of California San Diego School of Medicine in La Jolla, CA. Dr. Zablow shared his comments on this study:
“Exercise has often been called brain food with many studies showing the benefit of exercise in improving brain health and reducing the risk of dementia.”
“This current research study claims that physical activity improves cognitive brain function by lowering BMI and improving insulin metabolism. Improved weight control may limit the rate of brain volume loss, a known risk factor for dementia.”
“This study will help clinicians reinforce the importance of regular exercise in lowering BMI as a low-cost means of limiting cognitive decline.”
– Dr Zablow
Dr. Moore’s closing comments were: “The literature clearly demonstrates that cardiovascular risk factors are associated with cognitive decline and risk of Alzheimer’s disease and related dementias.”
“Studies investigating subtle changes in the brain before the development of dementia are critical to optimizing brain health and avoiding cognitive decline.”
“Strengths of this study include a sample of cognitively normal older adults and the use of multimodal imaging methods to explore the role of CVD risk factors in the association between physical activity and neuroimaging. biomarkerssaid Dr. Moore.
“[T]their methodology may advance the field by helping to identify important risk markers for cognitive decline.”
“A limitation of the study was the use of a self-report of physical activity […] which the authors acknowledged as a limitation. Self-report of physical activity is prone to hindsight bias, and objective tools for measuring physical activity, such as physical activity trackers, are more accurate.”
“These findings that insulin and BMI fully mediated the relationship between physical activity and whole-brain gray matter volume, and specifically hippocampal gray matter volume of matter — provide further evidence that the orientation of these modifiable factors CVD risk factors could improve brain health.”
