can exercise make you smarter?

22Mar07

The Frontal Cortex, a great science blog on matters cerebral if ever there was one, points to a story in Newsweek asking “can Exercise Make You Smarter?“. The answer very obviously turns out to be yes. The precise mechanisms are complex, Newsweek says:-

Researchers are realizing that the mental effects of exercise are far more profound and complex than they once thought. The process starts in the muscles. Every time a bicep or quad contracts and releases, it sends out chemicals, including a protein called IGF-1 that travels through the bloodstream, across the blood-brain barrier and into the brain itself. There, IGF-1 takes on the role of foreman in the body’s neurotransmitter factory. It issues orders to ramp up production of several chemicals, including one called brain-derived neurotrophic factor, or BDNF. Ratey, author of the upcoming book “Spark: The Revolutionary New Science of Exercise and the Brain,” calls this molecule “Miracle-Gro for the brain.” It fuels almost all the activities that lead to higher thought.”

Crikey.

But, Frontal Cortex blogger Jonah Lehrer comments:-

Obviously, BDNF really isn’t Miracle-Gro for the brain. There’s no such thing. But BDNF has been implicated in several important aspects of brain function. For starters, BDNF is repressed in response to stress. (After a stressful event, the brain releases glucocorticoids, which seem to repress BDNF.) Reduced levels of BDNF have also been implicated in depression, and it’s now thought that one of the mechanisms of action of anti-depressants is to raise cortical levels of BDNF. Finally, high levels of BDNF also up-regulate the mechanisms underlying plasticity and neurogenesis. (This is why stress reduces neurogenesis.)”

It’s perhaps no surprise that this kind of research is emerging now and so much attention is being paid to it. The response of many of us no doubt to the excess demands of such an information rich and complex environment is to try and find things that make us better able to cope.

While not empirical, it is very evident that when you fall off an exercise regime for an extended period, you do start to experience a decline in alertness which I sense is more than just a simple physiological decline in oxygenisation etc., but something more visceral. For instance, the virus that has kept me from running the past four weeks has gradually eroded the speed with which I complete certain mental tasks, particularly where evaluating choices or options is concerned.

Music-making, whether singing or playing an instrument, seems to compensate. Rugby player Jonny Wilkinson, as we have observed, has experienced chronic injuries and pursued language study and music to help keep his focus during lay-offs.

It would be good if this were taught in schools. But in a way, it is.

My fitness stats today:-

Resting Heart-Rate 50

Weight 71.5 kg

Mood