Like I told you in my last post, the lifestyle we choose has very much to do with how the brain ages. Here I will discuss the impact of exercise on brain-structure.
Just the word “exercise” makes my guilty conscience flare up. I bought a year´s membership to a gym club last October. In retrospect, I was pretty pleased with myself the first month, although I probably reached my goal of exercising five times a week only once. Since then my rate of attendance has been steadily declining. Why is it so difficult to fit exercise into the daily schedule?
Brain volume and physical exercise
There are relatively few studies available on the impact of exercise on brain volume, but the few I found suggest that cardiovascular fitness is associated with reduction of age-related decline in volume of brain-tissue.
One study explored the relationship between aerobic fitness and brain tissue density in 55 healthy individuals, 55 to 79 years of age. Participants were grouped into two groups according to their cardiovascular fitness. The result showed that the less fit group had more extensive decline in brain volume than the fit group. The brain areas where the difference between the groups was the most prominent were the areas that are most sensitive to age-related decline.
Another study examined whether six months of aerobic fitness training could increase brain volume of 59 healthy but inactive individuals, aged 60-79. Half of the participants were assigned to an aerobic training group, the other half to toning and stretching control group. The results showed an increase in brain volume of the aerobic training group but not in the non-aerobic control group, suggesting that to impact brain volume, the heartbeat has to be elevated for a certain period of time during the exercise.
The third research examined the relationship between aerobic fitness and the volume of the hippocampus. The results showed that higher fitness levels were associated with increased hippocampal volume in older individuals, which translated to better memory function.
Physical exercise and neurotrophic factors
Animal studies strongly suggest that physical exercise is highly effective in enhancing brain health, by stimulating neurogenesis (yes that’s right, the information we got 20 years ago, that neurons are incapable of regeneration, was less than accurate), increase resistance to brain insult and promote brain plasticity.
Neurotrophic factors are a family of proteins that instigate the survival, development and functions of neurons. BDNF (brain derived neurotrophic factor) is a neurotrophin. It supports the survival of neurons, encourages the growth of new neurons and synapses and influences memory and learning. BDNA also enhances neurogenesis. Research has shown that exercise increases the level of BDNF in blood significantly.
Physical exercise is probably the simplest way to protect your brain against the influence of aging and is particularly important prevention strategy for us middle-aged people!
Finally – here is a video from Youtube.com that shows people who claim to dance to forget. Dancing is a fun way to exercise, much more fun than the treadmill, so I am going to tune up the volume … and dance … NOT to forget!
-Colcombe, S. J., Erickson, K. I., Raz, N., Webb, A. G., Cohen, N. J., McAuley, E., & Kramer, A. F. (2003). Aerobic fitness reduces brain tissue loss in aging humans. The Journal of Gerontology 58A(2), 176-180.
-Colcombe, S. J., Erickson, K. I., Scalf, P. E., Kim, J. S., Prakash, R., McAuley, E., Kramer, A. F. (2006). Aerobic exercise training increases brain volume in aging uumans. The Journals of Gerontology Series A: Biological Sciences and Medical Sciences, 61(11), 1166-1170.
– Cotman, C. W., & Berchtold, N. C. (2002). Exercise: a behavioral intervention to enhance brain health and plasticity. Trends in Neurosciences, 25(6), 295-301.
-Erickson, K. I., Prakash, R. S., Voss, M. W., Chaddock, L., Hu, L., Morris, K. S., Kramer, A. F. (2009). Aerobic fitness is associated with hippocampal volume in elderly humans. Hippocampus, 19(10), 1030-1039.
-Rasmussen P, Brassard P, Adser H, Pedersen MV, Leick L, Hart E, et al. (2009). Evidence for a release of brain-derived neurotrophic factor from the brain during exercise. Experimental Physiology, 94(10), 1062-1069.