Just read an article in ScienceNews about the protective effects of robust exercise on the brain. Although the study was in monkeys, very small and Parkinson's specific, it's one more shred of evidence in favor of the positive effect of exercise on the brain even in the face of adverse factors (like MS?).
You can read it at:
http://www.sciencenews.org/view/gene...ns_bounce_back
AMF
You can read it at:
http://www.sciencenews.org/view/gene...ns_bounce_back
AMF