Exercise remains one of the best interventions to improve cognition, memory, and executive function in older adults, as well as, those with a decline in these functions such as Alzheimer’s disease and dementia. The research has developed from correlational studies showing more active individuals demonstrated higher cognitive function to more recent studies showing the impact of exercise alone on these variables in older adults, at risk groups, and patients diagnosed with diseases of the brain. The mechanisms behind exercise’s effectiveness continue to be studied but are thought to involve changes in inflammatory markers, circulation, and metabolic activity in the brain following acute and repeated bouts of exercise. A recent study shines light on one possible mechanism behind its’ effectiveness in these populations.

Previously researchers have found elevated beneficial blood markers including liver enzymes (Gpld1) in trained mice and older adults who exercised regularly. These enzymes are higher in more active adults and are thought to contribute, in part, to the beneficial cognitive and mental health benefits from exercise in older adults. Horowitz and colleagues studied the impact of administering blood from actively trained mice into sedentary mice to determine if the blood enzymes (increased Gpld1 concentrations) could improve the recipient’s cognitive function. (Science. 2020). Interestingly, the sedentary mice received some of the same cognitive and brain benefits as their active peers after the the blood transfer. In particular, they reported increased neuron development in the hippocampus region of the recipient animal’s brains.

The study establishes an important mechanism behind the effect of exercise on brain health and may lead to new medications mimicking the actions of exercise on the aging the brain.