ST. LOUIS — Numerous studies suggest a regular exercise schedule and practicing mindfulness can be beneficial for older adults looking to keep their minds sharp. Surprisingly, however, new joint research focusing on both of those lifestyle choices finds no evidence whatsoever that either approach boosts cognitive function in older individuals.
Scientists at the Washington University School of Medicine in St. Louis and the University of California, San Diego led the research behind the concerning conclusion. They assessed the cognitive repercussions of exercise, mindfulness training, or both for a period lasting up to 18 months among a group of older adults experiencing normal age-related changes in memory. Importantly, no included participants had been diagnosed with any form of dementia.
“We know beyond any doubt that exercise is good for older adults, that it can lower risk for cardiac problems, strengthen bones, improve mood and have other beneficial effects — and there has been some thought that it also might improve cognitive function,” says first study author, Dr. Eric J. Lenze, head of the Department of Psychiatry at Washington University’s medical school, in a university release. “Likewise, mindfulness training is beneficial because it reduces stress, and stress can be bad for your brain. Therefore, we hypothesized that if older adults exercised regularly, practiced mindfulness or did both there might be cognitive benefits — but that’s not what we found.”
Cognitive effects may become more apparent over a longer time period, so the research team is already planning to continue studying the same group of older adults. While future observations could support the notion that exercise and mindfulness may help prevent future cognitive declines, this latest project did not yield any evidence of such a relationship.
“So many older adults are concerned about memory,” adds senior study author Julie Wetherell, PhD, a professor of psychiatry at UC San Diego. “It’s important for studies like ours to develop and test behavioral interventions to try to provide them with neuroprotection and stress reduction as well as general health benefits.”
Memory tests across groups of active and inactive seniors reveal surprising results
Researchers studied a total of 585 adults between ages 65-84. While none had been diagnosed with dementia, all reported concerns over minor memory issues and other age-related cognitive declines.
“Minor memory problems often are considered a normal part of aging, but it’s also normal for people to become concerned when they notice these issues,” notes Prof. Lenze, who also directs Washington University’s Healthy Mind Lab. “Our lab’s principal aim is to help older people remain healthy by focusing on maintaining their mental and cognitive health as they age, and we were eager to see whether exercise and mindfulness might offer a cognitive boost in the same way that they boost other aspects of health.”
All study participants were deemed cognitively normal for their age ranges. Each subject was tested upon enrolling in the study, with researchers measuring memory and other aspects of thinking. Brain scans were also conducted. Then, subjects were randomly assigned to one of four groups: One that worked with trained exercise instructors; a group supervised by trained experts in mindfulness; a group that participated in both regular exercise and mindfulness training; and a control group that did neither, but did meet for sporadic sessions focused on general health education topics.
Memory tests were then held, as well as follow-up brain scans, after six months had passed, and then again after a year and a half.
At the six month mark, and again after 18 months had passed, all four groups looked similar. All of the groups performed slightly better in testing, but researchers posit this was due to practice effects; participants retook tests similar to what they had taken previously. Similarly, subsequent brain scans showed no differences between the groups that would indicate cognitive benefits.
‘We thought we might find a cognitive benefit — we didn’t’
To be clear, Prof. Lenze stresses that these findings shouldn’t discourage anyone from exercising or trying mindfulness training. This work does not mean exercise or mindfulness training won’t help improve cognitive function in any older adults. These findings simply indicate both practices do not appear to increase cognitive performance among healthy people without impairments.
“We aren’t saying, ‘Don’t exercise’ or, ‘Don’t practice mindfulness,’ ” Prof. Lenze explains. “But we had thought we might find a cognitive benefit in these older adults. We didn’t. On the other hand, we didn’t study whether exercise or mindfulness might benefit older adults who are impaired, due to dementia or to disorders such as depression. I don’t think we can extrapolate from the data that these practices don’t help improve cognitive function in anyone.”
Prof. Lenze adds the research team recently received funding from the National Institutes of Health (NIH) to continue following this group of study participants.
“They are still engaging in exercise and mindfulness,” he concludes. “We didn’t see improvements, but cognitive performance didn’t decline either. In the study’s next phase, we’ll continue following the same people for five more years to learn whether exercise and mindfulness training might help slow or prevent future cognitive declines.”
The study is published in JAMA.