New research funded by Alzheimer’s Research UK and the Medical Research Council sheds light on how staying active throughout your life is linked to changes to the brain, which may make you more ‘cognitively resilient’ and less likely to get dementia.
Led by Dr Sarah-Naomi James, scientists at UCL found that people who engaged in leisure activities involving exercise, especially before the age of 50, had changes in their brain, including a larger hippocampus, the area mainly responsible for memory.
People who exercised throughout life were also less likely to experience cognitive decline, even if they had key markers of Alzheimer’s such as amyloid build-up and brain shrinkage. This was especially true for women.
Understanding more about how exercise physically changes the brain and potentially protects people from dementia could lead to new interventions in the future, that can stop the condition from happening in the first place.
The findings were published recently in Brain Communications.
Dr team previously showed that leading an active life, particularly before age 50, was linked to better memory and thinking abilities at age 70. But until now, it was not clear how regular exercise helps to keep the brain healthy.
As part of the Insight46 study, the team collected information on how frequently a person self-reported taking part in physical activity for leisure across 30 years, before and after they turned 50. The team then analysed brain scans taken when the participants were 70 years old, to see if physical changes in the brain were linked to lifelong exercise.
The team found that people who said they exercised once or more a month from before they were 50 years old tended to have less shrinking in the brain’s memory centre, the hippocampus. This area is often the first brain region affected in Alzheimer’s disease.
Being physically active wasn’t directly related with other Alzheimer’s disease markers in the brain, like amyloid plaques or overall brain shrinkage. However, being active throughout life helped those with early Alzheimer’s disease markers to maintain and buffer their cognitive function, and this was particularly the case for women.
Evidence suggests that keeping our brains healthy can help build ‘cognitive reserve and resilience’, helping to help maintain memory and thinking in older age for longer. This is despite the brain aging and having signs of Alzheimer’s disease.
Again, this beneficial effect was even more prominent in women. Those who had signs of Alzheimer’s disease in their brain, but who were active in the past were more likely to have better cognitive function than those who were always inactive.
Further research will be needed to explore what aspects of leisure time physical activity may be driving this relationship. This could in the future be used as a preventative intervention for Alzheimer’s disease, said the authors.
