Give your brain a workout

Strength training benefits the brain

Some scientific research shows that strength training — building muscle by lifting weights — doesn’t improve intelligence and memory. But that doesn't mean there's no brain boost. Marco Tulio de Mello from Brazil’s Federal University of Sao Paulo has discovered that weight training also affects the brain, albeit in a different way than cardiovascular exercise.

Mello and his colleagues studied rats that either ran in an exercise wheel or worked out by climbing a ladder with weights taped to their tails for eight weeks. Subsequently, when the rats were tasked with finding their way through a water maze, both groups performed equally well and much better than the control subjects that hadn’t done the physical training. For the rats, strength training was just as beneficial as cardio.

The scientists then measured the rats’ levels of BDNF and other substances that assist in neuron growth in the brain.The results showed that, while both types of exercise increased the brain's production of crucial growth factors, they produced different chemicals and affected the nerve cells in different ways.The researchers concluded that strength training and cardio both can strengthen the brain, but that they do it in different ways, and they may actually stimulate different mental abilities.

Does physical fitness affect an older person's ability to focus on a particular, or even diffi-

cult, task?

ln a test conducted by assistant professor Ruchika Shaurya Prakash of Ohio State University, 70 subjects, who averaged 65 years of age, were tasked with identifying the color — red, green or purple — in which a given word was written by pressing a button of the corresponding color.

In the easy version of the test, the word "green" was written, as would be expected, in green letters. In the difficult version of the test, the word was not written in the color it described; for example, the word “purple” might be written in green, which could potentially cause the subject to become confused and press the purple button instead ofthe green one.

Before the test, the participants were rated according to their physical fitness. During the task, their brain activity was measured with an fMRI scan:The fitter the subject, the faster he or she performed the difficult test.

Brain scans explain why the more physically fit participants performed best. Two areas of the brain were particularly active in these test subjects while they were solving the difficult problems.They were not — as you may have expected— the areas perceiving the written word or certain colors, but two other areas that control higher cognitive processes.

The most active seniors were better able to activate more analytically brain centers than those who were less active.