This book focuses on the benefits of exercise for prevention and treatment of chronic brain disorders.  It is a guide for finding the right exercise routine for each individual.  The goal is to show the reader why everyone needs to exercise, especially as we get older.  The brain needs physical exercise both for normal health and for preventing and treating diseases common with aging. How much exercise is needed?  As we see throughout the book there is no one fits all rule with regard to the amount of exercise required.  The key is to make exercise a part of one daily routine.  The beneficial effect of exercise is transient, lasting days to weeks, so it must be a lifelong pursuit.  Can we exercise too much?  Anything done in excess can potentially be dangerous but with the common sense approach outlined in this book anyone, regardless of underlying health condition, can find some type of exercise that is safe and effective.