Pumping iron to ward off dementia

A team of Australian researchers has determined that hitting the gym twice a week can help ward off dementia and Alzheimer’s disease.

Published in the Journal of the American Geriatrics Society, the study found that adults over 55 years of age with mild cognitive impairment (MCI) showed improved brain function as their muscle strength increased. It was led by the University of Sydney in collaboration with the University of Adelaide and the Center for Healthy Brain Ageing (CHeBA) at the University of New South Wales.

It is estimated that over 100 million people will be living with dementia by mid-century; therefore, ensuring quality of life for our growing ageing population is essential. Previous studies had indicated that exercise is key for those classified with MCI if they wish to maintain their independence and ward off Alzheimer’s disease.

The Study of Mental and Resistance Training (SMART) involved 100 adults between ages 55 and 86, who are still living independently but are diagnosed with MCI. The double-blind trial divided the subjects into four groups including a placebo group, plus three different levels of exercise and brain training. For the first time, a direct causal link between brain function and exercise was empirically observed.

Lead author Dr Yorgi Mavros, from the Faculty of Health Sciences at University of Sydney, said: “What we found in this follow-up study is that the improvement in cognition function was related to their muscle strength gains ... The stronger people became, the greater the benefit for their brain.”

The ideal regime is weightlifting sessions twice a week, working to at least 80% of peak strength. As subjects grow stronger, exercise intensity needs to increase to maintain the 80% of peak strength level.

Dr Mavros claimed: “The more we can get people doing resistance training like weightlifting, the more likely we are to have a healthier ageing population.”

This research builds on earlier studies indicating that global cognition improves significantly after resistance training. One of those studies was published earlier this year and funded by Australia’s National Health and Medical Research Council.

University of Sydney geriatrician and senior author Professor Maria Fiatarone Singh said: “The next step now is to determine if the increases in muscle strength are also related to increases in brain size that we saw ... 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 maximise these effects.”

Image courtesy of Joy Weinberg under CC BY-NC-ND 2.0