How to keep your brain sharp

Doing the odd Sudoku puzzle might help, but a lack of exercise reduces the number of neurons in our brains, and also dulls our memory and our ability to resolve conflict. Photo / Thinkstock

Keeping your brain sharp requires more than just a game of Sudoku each day, says an expert holding a public talk in Auckland tomorrow.

Dr Jim Stinear, of the University of Auckland's Department of Sport and Exercise Science, will explain how not getting enough physical exercise can affect the brain when he speaks at Selwyn College tomorrow night.

Particularly, a lack of exercise reduces the number of neurons in our brains, and also dulls our memory and our ability to resolve conflict, he said.

"Scientific literature strongly supports the use of physical activity to enhance brain function," he said.

"If we are not exercising then our natural reduction in neurons in parts of the brain advances at quite a reasonable rate.

"In fact, the mental decline of a lot of healthy older people is now considered to be a result of a lack of proper blood flow to the brain, rather than just ageing nerve cells."

Just 150 minutes of moderate exercise each week could also have powerful effects on the hippocampus -- the part of our brain that controls brain function in general and cognitive skills.

The hippocampus also has important and direct connections to the brain's anterior cingulate cortex, which has an incredible array of associations, among them detecting errors, being rational, attention, motivation, decision-making, empathy and emotion.

"So if all that starts to dry up, then all those things become diminished and you're just not the same person you used to be."

Dr Stinear said while crosswords and mind games could help you sharpen your ability to complete puzzles, that would be lost if you didn't nourish your brain through physical exercise and other boosters like eating and sleeping well -- and even engagement with others.

"That's really about keeping your mind active -- when you are sad, or grumpy, or depressed, a lot of your energy is going into that and not allowing your brain to be smarter."

In his talk, Dr Stinear will describe the science of exercise and brain health, and offer simple and low-stress tips on how to preserve the brain.

The hour-long seminar will be held at Selwyn College, Kohimarama Road, from 7.30pm tomorrow -- those wishing to attend should register by emailing info@selwyncomed.school.nz or phoning the office on 09 521 9623.