Focus on fitness, not just weight, for the sake of your brain

An Australian study linking brain mass to physical activity has given middle-aged and senior Australians a goal to follow into later life.

Monash University researcher Chris Moran’s study shows brain health is improved by exercise.

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Keeping fit is good for your brain, not just your waistline, Australian research has shown, offering benefits for cognitive health and brain mass not linked to body weight.

A Monash University study published in Nature Scientific Reports suggested mid-life and older adults could prioritise their cognitive health by exercising for fitness, not just to lose weight, after finding a correlation between physical activity and brain volume.

Beyond just analysing the time spent on intentional exercise, the study pulled in analysis of incidental fitness from walking and everyday activities.

Lead researchers Alexandra La Hood and Chris Moran suggested physical activity might support brain health by improving cardiovascular health and by reducing inflammation.

“You shouldn’t focus on physical activity as purely being a way to reduce weight,” Associate Professor Moran said.

“Physical activity is far more complicated and has lots of benefits. We know that doing exercise helps release lots of really good chemicals that are good for your brain and good for your wellbeing.

“We’re beginning to realise there are benefits to be had at any stage of life, whether childhood, adolescence, mid-life or later life.

“If you’re not able to reduce your weight, you’re probably still getting lots of really good benefits from being physically active.”

While high weight and body mass index was associated in some cases with poor cognitive outcomes, it was a far less decisive cognitive health component than physical activity.

A Monash Study has shown exercise can help to maintain brain health.

“Mid-life is a particularly important time where a lot of us are very busy, and there are lots of things we probably can do that will have real meaningful benefits for us as we get older in regards to maintaining our brain health,” Professor Moran said.

“By having such a large sample size, we were able to see that not only was physical activity associated with better brain health … (it) was good for your brain health ­regardless of how heavy you may be, or what your body mass index may be.

“You may be doing physical exercise, you may simply be being physically active – either is good for your brain.”

The study relied on brain scan data and accelerometer tracking of physical exercise by 16,700 participants sourced from the UK Biobank at an average age of 65, a majority of whom were women.

Fitness was associated with larger total brain, grey matter, white matter, hippocampal volumes, and fewer signs of decline.

Neuroscience Research Australia chief executive Matthew Kiernan pointed to Lancet research showing 45 to 50 per cent of dementia cases could be prevented through lifestyle interventions as further proof of the importance in maintaining a balanced diet and exercise through later life.

45 to 50 per cent of dementia cases could be prevented through lifestyle interventions, like maintaining a balanced diet and exercising through later life. Picture: Getty Images

“The key issues there relate to exercise, but also vascular health, … community engagement and mood,” Professor Kiernan said.

“An incredibly important aspect to maintaining brain health is also doing new things, like learning new languages, going to new countries, doing new hobbies, going a different way home from work – all of these things that challenge your brain.”

Dementia Australia medical adviser Michael Woodward called for an expansion of public education about the potential lifestyle changes that could hold back cognitive decline.

“We know about heart disease prevention, we know about lung cancer prevention, and what have you,” he said.

“The promotion of dementia prevention has been under­estimated, which is a shame because dementia is soon going to be the leading cause of death in both males and females. For all those reasons, dementia should get a lot more press but unfortunately it tends to be pushed to the back because it’s considered a disease of old age. It’s (mistaken for) senility or forgetfulness.”