“I’m not kidding; it’s Miracle-Gro for the brain!” The statement reminded me of some ridiculous infomercial infecting late night TV. In this case however, it was generated from the mouth of a world class neurobiologist, so I took notice. He was speaking of a substance called Brain Derived Neurotrophic Factor (BDNF). What immediately intrigued me was he claimed that BDNF was the link between exercise and improved brain function. For years I had read articles in both the medical and running journals touting the psychological benefits of fitness, yet here was proof that fit folks were happier folks. Dr.John Ratey, a clinical professor of psychiatry at Harvard, outlined in his amazing book “Spark: The Revolutionary New Science of Exercise and the Brain” how exercise increased the production of BDNF which in turn stimulated nerve cells to grow and connect in the Hippocampus, a tiny area in the brain responsible for a number of high level functions. This growth of new cells actually translated into better memory and quicker learning. He went on to claim that certain other chemicals were released by exercising muscles that improved functioning in the amygdala, the emotional center of the brain. The implications of this and other research are monumental.
Twenty-five years ago when I was in medical school we were taught that we were born with a set number of neurons (brain cells) and there were no more to be made…period. I remember joking in college about taking another late night excursion to the disco (yes, I am that old!) to “kill some brain cells” with Singapore Slings and Jack and Coke. We didn’t fret about the wholesale slaughter of brain cells as we all knew from biology class that we only used 20% of our brain anyway. In our way of thinking, that gave us a pretty good cushion! It was the unlucky folks born with fewer brain cells, and we all knew a few of those, who had the most to fear. We were wrong on all accounts. Now research is proving that new brain cells can be created, and formed in areas that have a major effect on cognition and emotions. Don’t take this as permission to guiltlessly get plastered; I don’t need to tell you of the disastrous effects of that, but it does open the door for medical miracles. The study of such alphabet soup as BDNF, IGF-1, and VGEF and other neuropeptides has given hope to developing successful treatments for senile dementia, Alzheimer’s and Parkinsonism. Medicine is not there yet, but we can conclude that getting fit by exercising regularly can reduce the incidence of these diseases as well as certain cancers and diabetes.
The great news is that you don’t have to train for a marathon to reap the benefits of fitness. The studies indicate that a brisk walk for 45 minutes three to four times a week can elicit these life enhancing outcomes.
One of the most exciting applications of this knowledge is illustrated by the Naperville school district. A middle class suburb south of Chicago, Naperville has been the focus of a real-life experiment documenting the benefits of fitness in kids. It is no surprise that kids who are active are more physically fit than their sedentary counterparts, but what has been found in Naperville is that these fit kids are also smarter! Over the past seventeen years the school district, consisting of 11 elementary schools, five junior high schools and two high schools, has made physical education an integral part of the school day (unlike the national average where only 6% of high schools have a daily PE program). Their gym class is not your typical dodge ball, basketball, softball curriculum (the average student in the typical hour long PE class spends 16 minutes actively moving). It is a program that promotes and measures fitness, not competition, and grades based on effort, not ability. They regularly run or ride bikes using donated treadmills and stationary bikes measuring effort by heart rate monitors. And they do it at a lower cost per student than comparable school systems! The results have been amazing. In 2002, 97% of entering freshmen were at a healthy body mass index (BMI) as compared to the national average of 65% and most striking was the impact that fitness had in the classroom. In that same year 96% of the eighth graders took the Trends in International Math and Science Test, an instrument designed to compare student’s knowledge level in different countries around the world. On the science part of the test the Naperville students scored the highest…in the world! Through a strict and comprehensive analysis it was shown that regular physical activity and fitness level correlated with the academic success of the Naperville students!
The message is clear. For adults and kids alike, regular aerobic exercise is not only good for the body, but it is great for the mind.
