Resistance training valuable in dementia fight for older adults

Older adults - get moving! That is the message of research from clinical trials released at the Alzheimer's Association International Conference in Vancouver this week describing how specific exercises are beneficial to improving mental functioning and reducing risk for cognitive impairment and dementia in healthy older adults and others with mild cognitive impairment (MCI).

Exercises such as resistance training, aerobics and balance-stretching training proved particularly beneficial in a variety of cognitive abilities, growth factors, brain structure and functional neural plasticity. The exercises also helped in reducing such risk factors as sleep quality and depression.

Dr William Thies, chief medical and scientific officer of the Chicago-based association, said greater funding is needed to study the most common form of dementia as by mid-century the group forecasts it will cost more than one trillion U.S. dollars in America alone for the care of people with Alzheimer's. Such volume will place a huge strain on health care systems and in particular, the families caring for such patients.

"Previously, we had seen positive associations between aerobic activity, particularly walking, and cognitive health. These latest studies show that resistance training is emerging as particularly valuable for older adults," he said.

According to Thies, with an estimated 5.4 million Americans currently living with Alzheimer's, a number that could possibly triple by 2050, increased exercise in older people may prove beneficial in preventing or delaying cognitive impairment and dementia.

"It is very important to learn more about factors that actually raise and lower risk for cognitive decline for Alzheimer's. To do that, we need long-term studies in large, diverse populations, and we need the research funding to conduct those trials."

Lindsay Nagamatsu, a PhD student at the University of British Columbia in Vancouver, worked with colleagues on the EXCEL ( Exercise for Cognitive and Everyday Living) who study the results of twice-weekly resistance training (weightlifting) and aerobics training (walking) in women 70-80, versus twice-weekly balance and tone exercises.

According to the Stroop Test, which measures selective attention, conflict resolution and a memory task, the resistance- training group did better than the balance and tone group, with the former leading to "functional changes in three brain regions involved in memory."

"MCI is a critical window to intervene against dementia," said Dr. Teresa Liu-Ambrose of the UBC and Vancouver Coastal Health Research Institute, the principal investigator of EXCEL and Nagamatsu's supervisor. "We found that twice-weekly resistance training is a promising strategy to alter the trajectory of cognitive decline in seniors with MCI."

If resistance training is too much, Dr. Kirk Erickson suggests moderate walking may grow the brain region related to memory and increase the nerve growth factor. With his University of Pittsburgh colleagues, their one-year study looked at 120 older adults without dementia. It compared a group that had been sedentary for the previous six months, to a moderate intensity walking group and a stretching-toning group.

After a year of exercise, the walking group showed noticeable improvement compared to the stretching-toning group. "Our findings suggest that the aging brain remains modifiable," Erickson said, "and that sedentary older adults can benefit from starting a moderate walking regime."