- 135 million people will live with dementia globally by 2050
- Study conducted in adults over 55 with mild cognitive impairment (MCI)
- Increased muscle strength associated with improved brain function
In adults with Mild Cognitive Impairment (MCI), increased muscle strength leads to improved brain function.
Mild Cognitive Impairment (MCI) is an intermediate stage between the expected cognitive decline of normal aging and more serious decline of dementia.
‘Increasing muscle strength can help improve brain function in elderly people over 55 years who have with mild cognitive impairment.’
The findings are important as MCI can increase the risk of Alzheimer's disease and other forms of dementia.
Study of Mental and Resistance Training (SMART) trial involved 100 adults, aged between 55 and 86 from the community who had Mild Cognitive Impairment.
SMART was conducted in collaboration with the Centre for Healthy Brain Ageing (CHeBA) at University of New South Wales and the University of Adelaide.
Study participants were divided into four groups doing either
- Resistance exercise and computerized cognitive training
- Resistance exercise and a placebo computerized training (watching nature videos)
- Brain training and a placebo exercise program (seated stretching/calisthenics)
- Or Placebo physical exercise and placebo cognitive training.
The group participants were prescribed weight lifting sessions twice a week for six months, working to at least 80 per cent of their peak strength. As they got stronger, the amount of weight they lifted on each machine was increased to maintain the intensity at 80 per cent of their peak strength.
Relationship between muscle adaptations to progressive resistance training and the functioning of the brain was observed among those over 55 years of age with MCI.
MRI scans showed an increase in the size of specific areas of the brain among those who took part in the weight training program. These brain changes were linked to the cognitive improvements after weight lifting.
"What we found in this follow up study is that the improvement in cognition function was related to their muscle strength gains" said lead author Dr Yorgi Mavros, from the Faculty of Health Sciences, at University of Sydney. "The stronger people became, the greater the benefit for their brain. The more we can get people doing resistance training like weight lifting, the more likely we are to have a healthier ageing population," said Dr Mavros.
"The key however is to make sure you are doing it frequently, at least twice a week, and at a high intensity so that you are maximizing your strength gains. This will give you the maximum benefit for your brain."
"The next step now is to determine if the increases in muscle strength are also related to increases in brain size that we saw," said senior author Professor Maria Fiatarone Singh, geriatrician at University of Sydney.
"In addition, we want to find the underlying messenger that links muscle strength, brain growth, and cognitive performance, and determine the optimal way to prescribe exercise to maximize these effects."
Findings of the study published in the Journal of American Geriatrics.