A team of Aussie scientists have recently made an incredible breakthrough in dementia research, publishing results clearly showing that weight training can slow down the progression of this devastating illness (1).
Dementia is something that affects a lot of people, with 1.2 million Australians caring for a family member who suffers from this condition. Three in ten adults over the age of 85 develop this debilitating illness and as modern medicine increases our lifespans, these numbers are expected to explode, with almost one million cases predicted by 2050. Dementia is the third leading cause of death in Australia, and sadly, there is currently no cure (2).
Scientists studied a group of 100 adults over 55 with mild cognitive impairment, a condition that increases the likelihood of developing dementia. Participants were broken up into two exercise groups – one group performed progressive, high intensity resistance training, and the second performed sham physical training in the form of low impact calisthenics, acting as a control group. This was paired with computer based brain training for half of each group, while the other half watched videos and did quizzes that were not designed to enhance cognition. Adults in the study trained 2-3 times a week, with supervision, for six months.
After following the protocol for six months, the researchers found that the resistance trained group showed significant improvement in cognitive function as measured by a standardised group of brain function tests called the Alzheimer's Disease Assessment Scale-cognitive subscale, which is used to gauge the progress of dementia. 48% of the exercise group fell into the range that can be considered cognitively 'normal', while only 27% of the non-exercisers scored in this range.
Not only did exercise improve cognitive function, but it also made an improvement in what psychologists call "executive function" - this includes things like planning, decision making, problem solving and reasoning. Going against what we'd expect, weight training was shown to be more effective than brain training, which was only able to improve memory.
The study participants were reassessed 18 months after the completion of the six month trial. Remarkably, the group that did resistance exercise maintained their cognitive benefits a year after the completion of the experiment, while brain training was shown not to have a long-term impact on cognition or memory.
This research is in its early days yet, but the finding that high intensity resistance training can fight off the development of dementia has the potential to increase the quality of life for many people, now and in the future.
We already know that exercise has a whole host of benefits as people age, including maintenance of mobility, bone strength, and cardiovascular health. Now we have compelling evidence that exercise improves not just the body, but also the brain. This is just one more reason to get in the gym and lift!
(1) Fiatarone Singh MA, Gates N, Saigal N, Wilson GC, Meiklejohn J, Brodaty H, Wen W, Singh N, Baune BT, Suo C, Baker MK, Foroughi N, Wang Y, Sachdev PS, Valenzuela M. The Study of Mental and Resistance Training (SMART) study—resistance training and/or cognitive training in mild cognitive impairment: a randomized, double-blind, double-sham controlled trial. J Am Med Dir Assoc. 2014 Dec;15(12):873-80.
(2) Dementia: Key Facts and Figures 2014. <https://fightdementia.org.au/research-and-publications/reports-and-publications/key-facts-and-statistics>. Accessed February 16 2015.