"This is the mechanism by which the body cleans up most tissues. Except for the brain. The brain has a separate mechanism whereby lymphatic fluid (aka interstit

"This is the mechanism by which the body cleans up most tissues. Except for the brain. The brain has a separate mechanism whereby lymphatic fluid (aka interstitial fluid) gets flushed out, taking wastes with it, only during sleep." I've been thinking about this myself and I theorize that this all comes back, full circle, to your heart. That is, both bodily and brain lymphatic fluid flushing mechanisms are driven by circulation - and the more efficient and powerful your blood circulation is, the more efficient and cleansing your lymphatic flushing will be. And thus, your brains lymphatic flushing, while not directly driven by exercise, still benefits greatly from exercise due to the improvement in total circulation.