GETTING your body moving is a key way to keep dementia at bay.
But lowering your risk of the might not take as much as you'd think, new research reveals.
Weight training just twice a week helps protect older people from , Brazilian researchers say.
Volunteers with mild cognitive impairment who practiced strength training showed improvements in memory and brain anatomy after six months, they said.
has been previously shown to improve strength and muscle mass, , and contribute to and mental health.
Now a new study conducted at the State University of Campinas (UNICAMP) suggests it protects the brains of older people against dementia.
The study involved 44 people with mild – a clinical condition between normal ageing and in which cognitive decline is greater than expected for age, indicating a higher risk of dementia.
Alzheimer's is the most common form of dementia.
It is thought to be caused by build-ups of proteins in the brain, including tau and amyloid.
Previous studies have suggested that viral infections, likefluandand even a severe case of , may increase the risk of dementia.
The latest study, published in the journal GeroScience, showed that strength training not only improved memory performance but also altered brain anatomy.
After six months of twice-weekly weight training, the participants showed protection against atrophy in the hippocampus and precuneus – brain areas associated with – as well as improvements in parameters that reflect the health of neurons.
Study first author Dr Isadora Ribeiro, of UNICAMP's School of Medical Sciences (FCM), said: “We already knew that there would be physical improvement.
“Cognitive improvement was also imagined, but we wanted to see the effect of weight training on the brains of older people with mild cognitive impairment.
“The study showed that, fortunately, weight training is a strong ally against dementia, even for people who are already at high risk of developing it.”
The research is the first to demonstrate what happens to the integrity of the white matter of people with mild cognitive impairment after weight training.
Study supervisor Professor Marcio Balthazar said: “It's [weight training] a less complex and cheaper treatment that can protect people from serious diseases.
“For example, the new anti-amyloid drugs approved in the United States indicated for the treatment of dementia and for people with mild cognitive impairment, cost around US $30,000 a year.
“That's a very high cost.
“These non-pharmacological measures, as we've shown is the case with weight training, are effective, not only in preventing dementia but also in improving mild cognitive impairment.”
The study participants were divided into two groups.
One group half underwent a resistance exercise programme with weight training sessions twice a week, at moderate to high intensity and with progressive loads.
The other half didn't exercise during the study period.
At the end of the six-month study, volunteers who practiced weight training showed better verbal memory and improved neuron integrity, with areas related to Alzheimer's protected from atrophy.
In contrast, the control group experienced worsening brain parameters.
Dr Ribeiro said: “A characteristic of people with mild cognitive impairment is that they have volume loss in some brain regions associated with the development of Alzheimer's.
“But in the group that did strength training, the right side of the hippocampus and precuneus were protected from atrophy.
“This result justifies the importance of regular weight training, especially for older people.”
‘Something to be hopeful about'
The research team believe that a longer period of training could lead to even more positive results than those reported in the study.
Dr Ribeiro said: “All the individuals in the bodybuilding group showed improvements in memory and brain anatomy.
“However, five of them reached the end of the study without a clinical diagnosis of mild cognitive impairment, such was their improvement.
“This leads us to imagine that longer training sessions, lasting three years, for example, could reverse this diagnosis or delay any kind of dementia progression.
“It's certainly something to be hopeful about and something that needs to be studied in the future.”
Researchers say weight training helps protect the brain from dementia by boosting a protein that supports neuron health. It also reduces inflammation in the body.
Prof Balthazar said: “Any physical exercise, whether weight training or aerobic activity, is known to increase levels of a chemical involved in brain cell growth.
“It can also mobilise anti-inflammatory T-cells. This is key.
“After all, the more pro-inflammatory protein that is released in the body, the greater the chance of developing dementia, accelerating the neurodegenerative process and forming dysfunctional proteins that eventually kill neurons.”
To assess these issues, the volunteers' levels of irisin and brain-derived neurotrophic factor (BDNF) were measured.
BDNF is a protein that plays a key role in supporting the growth, maintenance, and survival of neurons.
It also helps with synaptic plasticity, which is the brain's ability to adapt and form new connections.
Both irisin and BDNF are produced in response to muscle contraction and are associated with neural protection.
The results are currently being analysed.
Dr Ribeiro added: “It's a continuation of this study in which we'll try to better understand how these factors are related to changes in brain anatomy.
“We believe that it's a set of anti-inflammatory and neuroprotective factors that lead to these changes.”
