By Laura Helmuth, Scientific American
Research studies have found that for vital brain health, physical exercise is critical. One does not have to have specialized training to achieve cognitive gains or ward off cognitive decline. Everyday activities such as reading can help as well. Over the past decades, several studies have underscored the link between physical activity and cognition.
Activity-related Cognitive Enrichment
Researchers have reviewed evidence on activity-related cognitive enrichment in more than a dozen studies. Robert S. Wilson and his colleagues at Rush University Medical Center in Chicago recruited more than 4,000 elderly residents from a geographically defined community and rated their frequency of participation in seven cognitive activities, such as reading magazines.
At three-year intervals for an average of nearly six years, participants completed an in-home interview that included brief tests of cognitive function. More frequent cognitive activity at the outset was associated with a reduced rate of cognitive decline over time.
Link between Physical Activity and Cognition
Over the past decades, several studies have underscored the link between physical activity and cognition.
For instance, neuropsychiatrist Kristine Yaffe of the University of California, San Francisco, and her colleagues recruited 5,925 women older than 65 at four different medical centers across the US. The researchers assessed their physical activity by asking the women how many city blocks they walked and how many flights of stairs they climbed daily and gave them a questionnaire to fill out about their levels of participation in 33 different physical activities.
After six to eight years, the researchers assessed the women’s level of cognitive function. The most active women had a 30 percent lower risk of cognitive decline. Interestingly, walking distance was related to cognition, but walking speed was not. It seems that even moderate levels of physical activity can serve to limit declines in cognition.
This is a transcript from the video series Understanding Your Inner Genius. Watch it now, on Wondrium.
Key to Brain Fitness
Moderate movement is good, but toning your circulatory system with aerobic exercise may be the real key to brain fitness.
In a study of 1,192 healthy 70- to 79-year-olds, cognitive neuroscientist Marilyn Albert of Johns Hopkins University and her colleagues measured cognition with a battery of tests of language, verbal memory, nonverbal memory, conceptualization, and visuospatial ability. They found that the best predictors of cognitive change over a two-year period included strenuous activity and peak lung flow.
A study by epidemiologist Jennifer Weuve, then at Harvard University, and her colleagues examined the relationship between physical activity and cognitive change over a two-year period in 16,466 nurses who were older than 70. Participants logged how much time they spent per week in a variety of physical activities (running, jogging, walking, hiking, racket sports, swimming, bicycling, aerobic dance) over the past year and provided self-reports of walking pace in minutes per mile.
Weuve’s group observed a significant relation between energy expended in physical activities and cognition across a large set of cognitive measures.
Mental Performance over Long Timescales
Most research thus far has examined mental performance over relatively short periods of just several years. A few studies have begun to look at what happens over longer timescales.
Suvi Rovio, now at the University of Turku in Finland, and her colleagues examined the relationship between physical activity at middle age and risk of dementia an average of 21 years later, when the cohort was between 65 and 79 years of age. Subjects indicated how often they participated in leisure-time physical activities that lasted at least 20 to 30 minutes and caused breathlessness and sweating.
Conducting such activity at midlife at least twice a week was associated with a reduced risk of dementia in later life. Indeed, participants in the more active group had 52 percent lower odds of having dementia than the more sedentary group did.
Improvements in Cognition
Kirk Erickson and his colleagues at the University of Pittsburgh assessed self-reported physical activity alongside measures of regional brain volume. They reported an association between walking and retention of brain volume, which in turn predicted a reduced risk of dementia in 299 older adults over a period of 13 years.
Interestingly, it is not just aerobic forms of physical activity (such as walking, jogging, swimming, and bicycling) that have been associated with improvements in cognition. Teresa Liu-Ambrose, a professor of physical therapy at the University of British Columbia, found that resistance exercise improved aspects of executive control in older women.
Common Questions about Physical Fitness and Cognitive Gains
Neuropsychiatrist Kristine Yaffe and her colleagues assessed the physical activity of 5,925 women and gave them a questionnaire to fill out about their levels of participation in 33 different physical activities. After six to eight years, the researchers assessed the women’s level of cognitive function. The most active women had a 30 percent lower risk of cognitive decline, thus showing that even moderate levels of physical activity can serve to limit declines in cognition.
In a study of 1,192 healthy 70- to 79-year-olds, cognitive neuroscientist Marilyn Albert of Johns Hopkins University and her colleagues measured cognition with a battery of tests of language, verbal memory, nonverbal memory, conceptualization, and visuospatial ability. They found that the best predictors of cognitive change over a two-year period included strenuous activity and peak lung flow.
Epidemiologist Jennifer Weuve and her colleagues observed a significant relation between energy expended in physical activities and cognition across a large set of cognitive measures.
