Exercise has been linked to improving some symptoms of Alzheimer's disease, while lack of physical activity is shown to be a risk by previous research. Now, a new study shows that lean muscle mass contributes to preventing the disease onset.
According to a new study published in BMJ Medicine, high levels of lean muscle could help protect people from Alzheimer's disease. However, the authors said further research is required to understand the biological processes behind it, as reported by Healthline.
For this study, data on lean muscle mass, cognition and general health of 450,243 participants were collected from the U.K. Biobank. The researchers looked into associations between lean muscle mass and genetic variants using Mendelian randomisation. The findings showed that people with higher, lifelong levels of lean muscle mass had a 12% reduction in Alzheimer's risk, according to Medical News Today. To measure the amount of lean muscle in the arms and legs, the researchers used bioimpedance, an electric current that flows through the body at different rates.
The researchers also found that lean mass was linked with better performance on cognitive tasks. "This study supports current recommendations to maintain a healthy lifestyle to prevent dementia. It is a hopeful finding which gives patients agency in their neurologic health," Iyas Daghlas, one of the study authors, told Medical News Today.
One of the researchers explained that the affected brain cells in Alzheimer's show severe mitochondria dysfunction, which happens when neurons cannot generate sufficient energy to function. Lean muscle mass is an indicator of healthy mitochondria functioning. Hence, muscle or brain cells function well in the presence of healthy mitochondria.
Some of the ways to build lean muscle mass, according to the researchers, are regular exercise, such as four to five short sessions of strength, a diet focused on reducing insulin resistance, proper sleep, and reducing chronic stress, according to Medical News Today.
"These analyses provide new evidence supporting a cause-and-effect relation between lean mass and risk of Alzheimer's disease," the researchers said in a press statement, according to ANI.
Previous studies have found that exercise has a positive impact on brain health and could help prevent Alzheimer's disease. For instance, a 2021 study published in Nature Metabolism showed that irisin, secreted by muscles during exercise, could help deficits of the brain caused by Alzheimer's disease.