Your Brain on Exercise

By Susan DeLaney, ND, RN
2010 AANP President's Award Winner

Photo by DolfinDans via Flickr, used under the Creative Commons License.

Many of us have made a resolution for 2011 to increase or start exercising. This is a resolution that many of us make every year with the best of intentions and plans. We want to get in shape or lose weight or feel stronger or wear those clothes we could no longer get into this past year.

Science provides us with new knowledge on the benefits of exercise that may add the extra spark to get us moving and inspire a lifelong commitment to staying active. For a long time it was believed that you are born with a set number of brain cells that begins to decline as you aged. Alcohol and drugs acted an agents to rapidly speed that decline.

Your brain, you’ll be pleased to know, is packed with adult stem cells that, when given the right inspiration, will divide and differentiate to make new baby stem cells or neurons. This process, known as neurogenesis, means that we each have the potential continually to make new brain cells.

One of the major ways to do that is through exercise. In studies of older adults, Art Kramer of the University of Illinois at Urbana-Champaign found that walking 45 minutes three times per week improves memory and executive-control functions by about 20%. This effect may only be in those whose brains have begun to deteriorate, which starts to happen in our 20s. So that probably includes most of us!!

Dr. Jack Kessler, chairman of neurology at Northwestern University has done research on mice looking at the effects of exercise on the brain. According to Dr. Kessler, “As we age the brain stem cells tend to become less responsive. They don’t divide as readily and can slump into a kind of cellular sleep.” Bone-morphogenetic protein, or BMP, seems to be one of the substances in the brain that contributes to the inactivity of your stem cells, slowing the growth of your brain, making it older and less nimble.

Exercise seems to counteract the brain-numbing effects of BMP, as mice given running wheels in their cages had less BMP related brain activity within a week, an impressive responsiveness to increased activity levels. Also noted was the increase of a brain protein called Noggin, a nicely named protein which acts as a BMP antagonist. The more Noggin in your brain, the less BMP activity exists, translating into more stem cell divisions.

The exact details of the mechanisms involved are still under investigation, but it appears that these two substances (and likely others as well) interact with one another in the brain and affect new brain cell development. What is known for certain is that exercise definitively increases neurogenesis and the ability of your brain to function. According to Art Kramer, “A year of exercise can give a 70-year-old the brain the connectivity of a 30-year-old, improving memory, planning, dealing with ambiguity, and multi-tasking. You can think of fitness training as changing the molecular and cellular building blocks that underlie many cognitive skills.”

So procrastinate no more. Go out and build some new brain cells and have fun while you are doing it! Dance, swim, walk, do yoga, zumba, cycle, or do whatever inspires you to move! Happy New Year to you as well!