Aerobic activity may slow down or prevent mental decline, including Alzheimer’s.
If you are middle-aged or older and you can’t find your keys or can’t remember an old friend’s phone number, it can trigger worry your memory is “slipping” and, worst case scenario, you are heading for a diagnosis of dementia in a few years.
Thankfully, some memory glitches can be normal. But the truth is, dementia is a huge and growing problem in the U.S. for those over the age of 65. As many as 5 million Americans have Alzheimer’s and another 20 to 40 percent of people with dementia have other forms of memory robbing disorders, according to the National Institute of Neurological Disorders and Stroke. While there is no drug that can cure or help most forms of dementia long-term, scientists are finding something that may help stave off memory loss — aerobic exercise.
Previous studies have concluded exercise can help the brain — but how much and what kind does it take to keep dementia at bay? To answer that question, University of Kansas (KU) Medical Center researchers studied 101 healthy adults age 65 and older who showed no signs of mental decline.
The research volunteers were divided into four groups. A control group didn’t have any monitored exercise while the other groups all worked out three to five times a week with certified personal trainers at a local YMCA. One group exercised for 150 minutes a week, a second worked out for 75 minutes weekly, and a third group exercised for 225 minutes per week. All the exercise groups started out with lower target heart rates and less intense exercise until their fitness improved over the course of 26 weeks.
Although each group of exercisers saw some benefit, at the end of the study it was the research volunteers who exercised the longest and hardest who experienced the most dramatic improvements in several measures of their thinking processes. For example, most improved their visual-spatial processing (the ability to perceive where objects are in space and to accurately assess how far apart they are from each other), overall attention span, and focusing ability.
"Basically, the more exercise you did, the more benefit to the brain you saw," said neurologist Jeffrey Burns, MD, co-director of the KU Alzheimer's Disease Center and the research leader. "Any aerobic exercise was good, and more is better."
The research indicated the intensity of the exercise mattered even more than the duration.
"For improved brain function, the results suggest that it's not enough just to exercise more," said researcher Eric Vidoni, PhD, an associate professor of neurology at KU Medical Center. "You have to do it in a way that bumps up your overall fitness level."
Learning that working out regularly may help and possibly protect the brain from Alzheimer’s could be powerful motivation to get otherwise older couch potatoes moving. Marjorie Troeh, 80, who participated in the KU study, said she had witnessed the ravages of dementia in her own family — her grandmother and aunt suffered from Alzheimer’s.
"I love exercising my mind, but I hate exercising my body," she said. "I knew about the evidence that said exercise was good for endurance and agility, but I really didn't make any connection with that and brain health."
For another recent study, a team of researchers from Chinese University of Hong Kong and University College London followed the exercise habits and mental health status of over 15,000 elders 65 and older for six years. None of the research subjects had a history of stroke, Parkinson’s disease (which can affect memory), or cognitive problems when the research began.
The results showed certain kinds of exercise appeared to benefit the brain. While toning and stretching didn’t have an impact, daily aerobic or mind-body workouts (such as yoga and tai chi) lowered the odds of developing dementia.
November 12, 2015
Christopher Nystuen, MD, MBA