Assuming exercise is a cause of reduced risk, then the key is identifying why that’s the case.
The most common theory is that there’s a benefit from exercise increasing the blood flow, which increases the amount of oxygen that gets to the brain.
There’s also the possibility of benefits from improvements in the metabolism of brain cells and from increases in certain hormones and proteins that are good for brain cells, as Okonkwo and Snyder both noted.
With that mechanism nailed down, “that really opens that door to try to get those benefits in other ways,” Snyder said.
That could be lifestyle changes such as exercise or a drug that mimics those benefits — or even a combination of benefits that can be added up and impact the brain in an even stronger way.
For now, Snyder said, “what seems consistent is that exercise is beneficial even if you’re already having cognitive decline. But you would need to discuss it with a healthcare provider before starting a new exercise regimen.”