Exercise and the Brain

Exercise and the Brain

Saturday 14th December 2019
Jeff Murray

Exercise helps keep your mind active and alert - at any age

OK, here's the bad news: old age is associated with decreased brain function. Your memory and ability to learn will suffer as the two hippocampus (left and right) in your brain get smaller.

Now here's the good news: you can get parts of your brain, including the hippocampi, to create new cells. It's not true that you have a limited number of brain cells! As long as you provide the right stimulus for your brain, neurogenesis (brain cell creation) will continue pretty much as long as you are alive.
The importance of sleep

We've written before about the importance of sleep, and sleeping enough and sleeping well is now thought to be one important factor in preserving cognitive brain function. The other is aerobic exercise.
Exercise creates new brain cells - at any age

Studies done on rats and mice showed that giving them the opportunity to exercise created new blood vessels, and not only more neurons but stronger connections between the neurons, resulting in quicker thought processes - even in older animals.

Recent research has uncovered a similar link between exercise and brain function in older humans too. Two groups of 60 year olds (60 in each group) undertook a either a session of light stretching or mild aerobic exercise for three times a week, for fifty two weeks. Their hippocampi were measured with MRI at the start and end of the experiment, and it was found that:

whilst the group who only stretched saw an average loss of 1.4% of their hippocampi, the exercising group saw an average 2% gain; and
memory function was directly affected by the loss and addition of brain cells.

What sort of exercise?

And the sort of exercise that generated these results? Nothing more than a 40 minute brisk walk three times a week, with the first two months spent working up to this level of fitness. This is an extremely achievable goal for any reasonably able-bodied person.

Another study of older people found that those who had not regularly exercised throughout their lives had more atrophied brains than those who had made an effort to exercise, and another still found that both memory and learning ability could be stimuated through exercise. There are even indications that exercise can prevent and slow senile dementia.

Exercise has been shown to improve cognition more than 'brain-training' games and puzzles intended to stimulate mental activity; indeed one study that investigated these games found that the only brain function that improved was the ability to solve these puzzles: other cognitive functionality was not positively affected.

So, whilst your brain is more or less 'finished' before you are thirty, you can do a lot to keep it from wasting away (just like any other muscle) by exercising it: in this case with nothing more arduous than a few hours' walking every week.