Summary: According to researchers, aerobic exercise may be more effective than other forms of exercise when it comes to preserving cognition and slowing Alzheimer’s decline.
Source: American Geriatrics Society.
Alzheimer’s disease (AD) is a brain disorder that destroys memory and thinking skills over time. It is the most common form of dementia in older adults. There is presently no cure for the condition, though treatment options are available. Today, some 5.3 million Americans live with AD, and it is now the sixth leading cause of death in the United States. The number of older adults who will develop AD is expected to more than triple by 2050.
Geriatrics experts have suggested that exercising can improve brain health in older adults. The World Health Organization (WHO) has recommendations for how much older adults should exercise. They suggest that older adults perform 150 minutes a week of moderate exercise (such as brisk walking), 75 minutes a week of vigorous aerobic training, or a combination of the two types. The WHO also recommends older adults perform muscle-strengthening exercises on at least two or more days a week.
However, not all studies of exercise and older adults have proven the benefits of exercise. We don’t know for sure whether exercise slows mental decline or improves older adults’ ability to think and make decisions.
A team of researchers designed a study to learn whether exercise could delay or improve AD symptoms. They reviewed 19 studies that examined the effect of an exercise training program on cognitive function in older adults who were at risk for or diagnosed with AD. The studies included 1,145 older adults, most of whom were in their mid-to late 70s. Of the participants, 65 percent were at risk for AD and 35 percent had been diagnosed with AD.
The researchers published their findings in the Journal of the American Geriatrics Society.
As the researchers examined the studies, they discovered that older adults who did aerobic exercise by itself experienced a three times greater level of improvement in cognitive function than those who participated in combined aerobic training and strength training exercises. The researchers also confirmed that the amount of exercise WHO recommends for older adults was reinforced by the studies they examined.
Finally, the researchers found that older adults in the no-exercise control groups in the studies faced declines in cognitive function. Meanwhile, the older adults who exercised showed small improvements in cognitive function no matter what type of exercise they did.
The research team concluded that this study may be the first to show that for older adults who are at risk for or who have AD, aerobic exercise may be more effective than other types of exercise in preserving the ability to think and make decisions.
The researchers note that their findings need to be confirmed in future studies.
Source: Daniel E. Trucil – American Geriatrics Society
Publisher: Organized by NeuroscienceNews.com.
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Original Research: Open access research in Journal of the American Geriatrics Society.
Can Exercise Improve Cognitive Symptoms of Alzheimer’s Disease? A Meta-Analysis
To examine the effects of exercise training on cognitive function in individuals at risk of or diagnosed with Alzheimer’s disease (AD).
PubMed, Scopus, ClinicalTrials.gov, and ProQuest were searched from inception until August 1, 2017.
Nineteen studies with 23 interventions including 1,145 subjects with a mean age of 77.0 ± 7.5 were included. Most subjects were at risk of AD because they had mild cognitive impairment (64%) or a parent diagnosed with AD (1%), and 35% presented with AD.
Controlled studies that included an exercise-only intervention and a nondiet, nonexercise control group and reported pre- and post-intervention cognitive function measurements.
Cognitive function before and after the intervention and features of the exercise intervention.
Exercise interventions were performed 3.4 ± 1.4 days per week at moderate intensity (3.7 ± 0.6 metabolic equivalents) for 45.2 ± 17.0 minutes per session for 18.6 ± 10.0 weeks and consisted primarily of aerobic exercise (65%). Overall, there was a modest favorable effect of exercise on cognitive function (d+ = 0.47, 95% confidence interval (CI) = 0.26–0.68). Within-group analyses revealed that exercise improved cognitive function (d+w = 0.20, 95% CI = 0.11–0.28), whereas cognitive function declined in the control group (d+w = −0.18, 95% CI = −0.36 to 0.00). Aerobic exercise had a moderate favorable effect on cognitive function (d+w = 0.65, 95% CI = 0.35–0.95), but other exercise types did not (d+w = 0.19, 95% CI = −0.06–0.43).
Our findings suggest that exercise training may delay the decline in cognitive function that occurs in individuals who are at risk of or have AD, with aerobic exercise possibly having the most favorable effect. Additional randomized controlled clinical trials that include objective measurements of cognitive function are needed to confirm our findings.