Optimal Exercise Dose for Better Cognition Determined
04 de junho de 2018
The optimal dose of exercise for improved cognition in older adults is suggested by a new systematic review.
Building on numerous studies showing a positive relationship between regular exercise and improvements in brain health, researchers have determined that 52 hours over 6 months is the minimum amount needed to improve cognition in older adults.
In fact, total exercise time was the most important factor linked to improved processing speed and attention, executive function, and global cognition in a systematic review of 98 randomized controlled trials. This finding suggests that cognitive improvements associated with exercise act on the same constructs affected by cognitive aging.
Exercising in approximately 1-hour sessions to reach this total was associated with improved cognitive performance in older healthy adults, those with mild cognitive impairment, and others with dementia.
Interestingly, researchers report that cardiovascular exercise, resistance training, and mind-body exercises, or a combination of these, were advantageous. Running might work for some people, but patients with a bad hip or bad knee could still see benefit from lower-impact activities, such as yoga or tai-chi, study author Joyce Gomes-Osman, PT, PhD, assistant professor of clinical physical therapy and neurology at the University of Miami Miller School of Medicine in Florida, told Medscape Medical News.
"We were interested in finding practical advice that is evidence-based," she said.
The systematic review, published online May 30 in Neurology Clinical Practice,included 11,061 adults with a mean age of 73 years.
Older healthy adults represented 59% of the total population; another 26% had mild cognitive impairment and 15% had dementia based on Mini-Mental State Examination or similar measure scores.
Researchers compared cognition and memory between participants who exercised at least 4 weeks and others who did not start a new exercise regimen. In contrast to benefits reported at 52 hours, people who exercised an average of 34 total hours over the 6 months did not show improved cognitive skills.
Only total exercise time was associated with cognitive improvement in a bivariate analysis; session time in minutes, exercise frequency per week, and total number of weeks of exercise did not correlate with improved thinking skills.
"I was very surprised by that finding. Before coming in I had my bet set on weekly minutes," Gomes-Osman said.