Weight training might slow cognitive decline: study
Seniors who are in the earliest stages of dementia might be able to slow the disease by pumping weights a few times a week, new research out of Vancouver suggests.
Researchers at the Centre for Hip Health and Mobility at Vancouver Coastal Health and the University of British Columbia found that seniors in the earliest stages of dementia performed better on mental tests after just six months of twice-a-week resistance training.
The team studied 86 women who were between the age of 70 and 80 and who had probable "mild cognitive impairment."
People with MCI typically forget recent events or conversations, have difficulty performing more than one task at a time, and take longer to make decisions or perform calculations.
Having MCI puts one at greater risk for dementia, though, for reasons still not understood, not everyone goes on to develop it. MCI is thus considered an important window of opportunity for perhaps slowing cognitive decline.
For this study, the researchers divided the 86 women into three groups:
- One group performed an hour of resistance training twice a week
- Another performed an hour of aerobic exercise twice a week
- A third group did a twice-weekly "balance and tone" training sessions. This group was considered the control group
At the end of six months, the researchers then assessed the women using standardized tests for memory, problem solving, attention and decision making –- all skills necessary for independent living.
They also had the women undergo functional MRI scans of their brains to test for "brain plasticity."
The researchers found that those in the weight training group saw significant improvements in their "executive cognitive functions," such as being able to hold their attention on a task and resolving conflicts.
Their associated memory performance also improved compared to those in the "balance and tone" sessions. And the MRI scans showed their functional brain plasticity had improved.
The researchers note that their study was quite small, there was a high dropout rate and they aren't even sure whether the results would apply to men or to women of other ages.
But they say the study was meant to show "proof-of-concept" and to provide preliminary evidence that resistance training and aerobic exercise improve cognitive functions.
Teresa Liu-Ambrose, the study's principal investigator who's with the Centre for Hip Health and Mobility and the Brain Research Centre at VCH, says the study was meant to show that cognitive decline can be slowed with exercise.
"What our results show is that resistance training can indeed improve both your cognitive performance and your brain function," she said in a statement.
"What is key is that it will improve two processes that are highly sensitive to the effects of aging and neurodegeneration: executive function and associative memory -- often impaired in early stages of Alzheimer's disease."
She noted that the beauty of exercise is that it's simple and available to most seniors. Even seniors with limited mobility can perform some resistance training.
"Exercise is attractive as an prevention strategy for dementia as it is universally accessible and cost-effective," says Liu-Ambrose, who is who is also an assistant professor in the department of Physical Therapy at the University of British Columbia.
Liu-Ambrose's team previously demonstrated that 12 months of twice-weekly weight training significantly improved cognitive performance in cognitively healthy senior women. This study found an improvement after only 6 months in women with probable mild cognitive impairment.
They say that suggests that there might be even more benefits of weight training exercise among those at greater risk for dementia.
The study was conducted with researchers from the Department of Psychology and Division of Geriatric Medicine at UBC, and Department of Psychology at the University of Iowa, and published Monday in the Archives of Internal Medicine.