A meta-analysis from investigators Joyce Gomes-Osman, Danylo F. Cabral, Timothy P. Morris, and others was published in the journal Neurology Clinical Practice (published online May 30), and found good quality evidence that exercise has a positive effect on measures of cognition in older adults (mean age = 73). This held true for both those with and without cognitive impairments.
Other key findings are that exercising for at least 52 hours over approximately 6 months, in sessions lasting at least 1 hour, consistently correlates with improvements in measures of processing speed, attention, executive function, and global cognition, but not visuospatial or working memory (P = .01).
In contrast, people who exercised for less than this, with an average of 34 hours over the same time period, did not show any improvement in cognitive measures. The meta-analysis did not find a correlation between the number of times per week of exercise or the intensity of exercise, and the authors emphasize that although most of the study interventions used moderate exercise (defined as achieving 60% to 80% of maximum heart rate), they did not find moderate exercise to have superior effects on cognition compared to lower intensities.
The authors acknowledge that their results correlate an average of exercise amounts across studies of varying designs. They recommend future studies use agreed upon exercise parameters and cognitive outcome measures, especially global cognition scores.
“These results suggest that a longer-term exercise program may be necessary to gain the benefits in thinking skills,” said study author Joyce Gomes-Osman, PT, PhD, of the University of Miami Miller School of Medicine in Florida. “We were excited to see that even people who participated in lower-intensity exercise programs had a benefit to their thinking skills. Not everyone has the endurance or motivation to start a moderately intense exercise program, but everyone can benefit even from a less intense plan.”
The authors aimed to assess methodologic quality of studies on exercise and cognition, relationships between amount of exercise and improved cognition, and consistent patterns of effects. They included randomized clinical trials examining more than 4 exercise sessions in adults age 60 or more, with or without cognitive impairment, that included at least one neuropsychologic outcome measure.
Although only 98 of 4,612 research studies identified via search met these criteria, those studies together included over 11,000 individuals (3,491 men and 7,475 women). Approximately half of subjects (52.8%) were sedentary prior to the study they participated in, although the prestudy activity level for 30.9% of participants was not reported. Only 11.25% of participants were reported as being active prior to study activity.
Data related to session time, exercise intensity, frequency per week, number of weeks studied, intensity of exercise, and exercise modes were defined across all studies. Relationships between each of 5 measured neuropsychologic outcomes and each of the extracted exercise measures, except exercise intensity, were quantified. Exercise intensity was not included because it was not reported in all 98 studies.Next Story