Cardio exercise gets more blood to the aging brain


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We’ve been told repeatedly in recent years that exercise is good for the aging brain. An interesting new study, due to appear in next week’s issue of the American Journal of Neuroradiology, offers a clear picture (literally) of why that is. Researchers at the University of North Carolina at Chapel Hill took brain images (magnetic resonance angiographs, to be precise) of two groups of seniors — one group consistently exercised at least three hours a week, the other reported less than 90 minutes of any type of physical activity weekly:

Aerobically active subjects exhibited more small-diameter [blood] vessels with less tortuosity, or twisting, than the less active group, exhibiting a vessel pattern similar to younger adults…

The brain’s blood vessels naturally narrow and become more tortuous with advancing age, but the study showed the cerebrovascular patterns of active patients appeared “younger” than those of relatively inactive subjects.

It’s a pretty small study (14 subjects), and it’s always worth asking whether there are other underlying factors that could explain both the higher activity levels AND the better blood vessels in one group. Still, the link between aerobic exercise and nice big blood vessels seems pretty logical. Next step: take some sedentary seniors, get them to start exercising, and see if the blood vessels in their brains get bigger.