The Mind-Exercise Connection: Part 2

Say, that’s a big, healthy brain you’ve got there… You must be working out!

And we’re not talking sudoku here (though that can help, too), we’re talking regular aerobic exercise. In The Mind-Exercise Connection, Part 1, we showed you how exercise enhances memory and learning, increases oxygen to the brain, improves your mood, and relieves anxiety. But that’s not all exercise does for your noggin.

It also helps you build new and better brain cells.

That’s right. Aerobic exercise is a proven way to make you smarter. In the past decade, neuroscientists have repeatedly shown that the relationship between brainpower and exercise is more than significant. Aerobic exercise makes a brain resistant to shrinkage, grows new neurons and enhances cognitive flexibility.

Using mice and a maze, neuroscientists are proving that “exercise may bolster thinking more than thinking does,“ (New York Times Magazine, 4/22/2012). In 1999, scientists at the Salk Institute studied two groups of mice. The first group of 17 had access to a running wheel, where they clocked about three miles per day. The control group comprised 17 sedentary mice that lazed around the cage and ate and drank. The mice were injected with bromodeoxyuridine to label dividing brain cells, and trained in navigating a water maze.

Researchers noticed that the mice that ran on the treadmills outperformed the mice that were sedentary on the more challenging water maze tasks. And, when the mice’s brains were studied, the brains of active mice demonstrated enhanced neurogenesis — the creation of new brain cells — in the hippocampus. These findings led to the conclusion that increased neurogenesis in the runners improved their ability to learn something new and challenging. Since this study, more studies have been conducted on mice and humans that have found correlations between exercise and the connectivity of newborn neurons.

One human subject study, conducted by Colcombe and colleagues in 2006, used brain imaging techniques to study the effects of fitness on the human brain. This study randomly assigned 59 older adults to either a cardiovascular (aerobic) exercise group or to a stretching and toning (non-aerobic) group. Participants exercised three hours a week for six months and their brains were scanned before and after this training period. At the end of the six months, the brain volume of the aerobic group increased in several areas compared to the non-aerobic group. These increases occurred in the frontal and temporal lobe areas where memory processes and executive brain functioning take place. The authors of this study suspect, based on previous research on animals and exercise, that these volume changes in the brain probably were a result of increased number of connections between neurons and the increased number of blood vessels.

In short, there seems to be no other single activity that can do as much for your brain as aerobic exercise. It makes you sharper, keeps the brain better nourished, grows new neurons, and even helps neurons connect to each other to form new pathways in the brain.

So on your next trip to the gym, don’t concentrate on bigger biceps — concentrate on a bigger, better brain.

REFERENCES

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Erickson, K.I., Raji, C.A., Lopez, O.L., Becker, J.T., Rosano, C., Newman, A.B., Gach, H.M., Thompson, P.M., Ho, A.J., Kuller, L.H. (2010). “Physical Activity Predicts Gray Matter Volume in Late Adulthood: the Cardiovascular Health Study.” Neurology 75(16): 1415-22.

Housman, J., and Dorman, S. (2005). “The Alameda County Study: A systematic, Chronological Review.” American Journal of Health Education 36(5): 302-308.

Reynolds, G. (2012, April 18) “How Exercise Could Lead to a Better Brain.” New York Times.

Rovio, S., Spulber, G., Nieminen, L.J., Niskanen, E., Winblad, B., Tuomilehto, J., Nissinen, A., Soininen, H., Kivipelto, M. (2010). “The Effect of Midlife Physical Activity on Structural Brain Changes in the Elderly.” Neurobiology of Aging 31(11): 192-36.

Taupin, P. (2007). The Hippocampus: Neurotransmission and Plasticity in the Nervous System. New York: Nova BioMedical Books.

Van Praag, H., Shubert, T., Zhao, C., Gage, F.H. (2005). “Exercise Enhances Learning and Hippocampal Neurogenesis in Aged Mice.: Journal of Neuroscience 25(38):8680-8685.

Van Praag, H., Christie, B.R., Sejnowski, T.J., Gage, F.H. (1999). “Running Enhances Neurogenesis, Learning, and Long-Term Potentiation in Mice.” PNAS, 96(23): 13427-13431