A February 2020 study by the University of Wisconsin School of Medicine and Public Health said,

“This study is a significant step toward developing an exercise prescription that protects the brain against [Alzheimer’s], even among people who were previously sedentary," 

"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,"

"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."