When we think about the benefits of exercise on the body, most of us can come up with several examples such as improved muscle strength, reduced body weight, or a stronger heart. What research is beginning to show is that exercise benefits brain integrity. This concept is not new.
Ramon Y Cajal, Spanish scientist and Nobel prize winner in 1906, (summarizing the main conclusions of his paper on General Considerations on the Morphology of the Nerve Cell in 1894) said that “intellectual power, and its most noble expressions, talent and genius, do not depend on the size or number of cerebral neurons, but on the richness of their connective processes, or in other words on the complexity of the association pathways to short and long distances…Adaptation and professional dexterity, or rather the perfecting of function by exercise (physical education, speech, writing, piano-playing, mastery in fencing, and other activities) were explained by either a progressive thickening of the nervous pathways … excited by the passage of the impulse or the formation of new cell processes (non-congenital growth of new dendrites and extension and branching of axone collaterals) capable of improving the suitability and the extension of the contacts, and even of making entirely new connections between neurons primitively independent”. (Note: Read this passage at least 4 times-it is packed with much important content)
Even 125 years ago, Cajal was able to study connections between neurons and observed that these connections could change as a result of a stimulus. He proposed that exercise contributed to the richness of neuronal connections which was responsible for learning, “perfecting” and adaptation. The difference today is that we have fine-tuned measurement of cells and molecules such that we can determine what events or processes are actually happening inside the brain as a result of exercise. Indeed, “doing” or “exercising” seems to be critical to a healthy brain. More to come on this topic….
“The brain cannot stand like a monument, and maintain its integrity.”
William Henry Day (from Headaches; their Nature, Causes, and Treatment, 1880)