Although we generally understand exercise to be good fo us in all sorts of ways, scientists continue to make interesting inroads around the specifics of this relationship. The latest comes from a team in Germany which has found that even slight changes to regular physical activity, such as taking the stairs instead of the elevator, can counter the age-related loss of volume in brain regions linked to disease.
Research has demonstrated how exercise can help combat some of the effects of aging. This includes studies showing that regular physical activity can preserve the heart’s elasticity, reduce mild cognitive impairment and induce hormones that protect against Alzheimer’s and dementia. Scientists at the German Center for Neurodegenerative Diseases (DZNE) have looked to add to this growing body of evidence, by looking at exercise’s impacts on specific regions of the brain.
“In previous research, the brain was usually considered as a whole,” says Fabienne Fox, lead author of the study. “Our goal was to take a more detailed look at the brain and find out which regions of the brain physical activity impacts most.”
To do so, the scientists tapped into data from a population-based study of more than 2,500 subjects aged 30 to 94. This involved analyzing brain volume and thickness of the cortex through MRIs and assessing their physical activity, with the subjects made to wear an accelerometer on their thigh for seven days.
“We were able to show that physical activity had a noticeable effect on almost all brain regions investigated,” said Fox. “Generally, we can say that the higher and more intense the physical activity, the larger the brain regions were, either with regard to volume or cortical thickness. In particular, we observed this in the hippocampus, which is considered the control center of memory. Larger brain volumes provide better protection against neurodegeneration than smaller ones.”
Those that stand to benefit most may be inactive older adults. The scientists found that the largest, and almost sudden, volume increases were observed when comparing inactive subjects over 70 with moderately active ones.
“In principle, this is very good news – especially for those who are reluctant to exercise,” says study author Ahmad Aziz. “Our study results indicate that even small behavioral changes, such as walking 15 minutes a day or taking the stairs instead of the elevator, may have a substantial positive effect on the brain and potentially counteract age-related loss of brain matter and the development of neurodegenerative diseases. In particular, older adults can already profit from modest increases of low intensity physical activity.”
Genetic analysis of brain regions most impacted by uptake in physical activity indicated that they are home to high amounts of mitochondria, which provide our body with energy but need a lot of oxygen to do so.
“Compared to other brain regions, this requires increased blood flow,” said Aziz. “This is ensured particularly well during physical activity, which could explain why these brain regions benefit from exercise.”
The analysis also revealed a large overlap in genes impacted by physical activity and those impacted by diseases such as Alzheimer’s and Parkinson’s. This offers a possible explanation for the protective benefits of exercise against these types of conditions.
“With our results, we want to provide a further impetus to become more physically active – to promote brain health and prevent neurodegenerative diseases,” said Fox. “Even modest physical activity can help. Thus, it’s just a small effort – but with a big impact.”
The research was published in the journal Neurology.
New Atlas, 4 August 2022