Exercise is good for the aging brain
Researchers find a single bout of exercise boosts cognition, memory performance in some older people
August 26, 2019
Science Daily/University of Iowa
Researchers have found that a single bout of exercise benefits some older people's brains. In experiments in which participants aged 60 to 80 exercised once and multiple times, the researchers found some individuals showed improved cognitive functions and working memory.
Exercise seems to endow a wealth of benefits, from the release of happiness-inducing hormones to higher physical fitness. New research shows it may provide a boost to the mind too.
University of Iowa researchers have found that a single bout of exercise improves cognitive functions and working memory in some older people. In experiments that included physical activity, brain scans, and working memory tests, the researchers also found that participants experienced the same cognitive benefits and improved memory from a single exercise session as they did from longer, regular exercise.
"One implication of this study is you could think of the benefits day by day," says Michelle Voss, assistant professor in the Department of Psychological and Brain Sciences and the study's corresponding author. "In terms of behavioral change and cognitive benefits from physical activity, you can say, 'I'm just going to be active today. I'll get a benefit.' So, you don't need to think of it like you're going to train for a marathon to get some sort of optimal peak of performance. You just could work at it day by day to gain those benefits."
Previous research has shown exercise can confer a mental boost. But the benefits vary: One person may improve cognitively and have improved memory, while another person may show little to no gain.
Limited research has been done on how a single bout of physical activity may affect cognition and working memory specifically in older populations, despite evidence that some brain functions slip as people age.
Voss wanted to tease out how a single session of exercise may affect older individuals. Her team enrolled 34 adults between 60 and 80 years of age who were healthy but not regularly active. Each participant rode a stationary bike on two separate occasions -- with light and then more strenuous resistance when pedaling -- for 20 minutes. Before and after each exercise session, each participant underwent a brain scan and completed a memory test.
In the brain scan, the researchers examined bursts of activity in regions known to be involved in the collection and sharing of memories. In the working memory tests, each participant used a computer screen to look at a set of eight young adult faces that rotated every three seconds -- flashcard style -- and had to decide when a face seen two "cards" previously matched the one they were currently viewing.
After a single exercise session, the researchers found in some individuals increased connectivity between the medial temporal (which surrounds the brain's memory center, the hippocampus) and the parietal cortex and prefrontal cortex, two regions involved in cognition and memory. Those same individuals also performed better on the memory tests. Other individuals showed little to no gain.
The boost in cognition and memory from a single exercise session lasted only a short while for those who showed gains, the researchers found.
"The benefits can be there a lot more quickly than people think," Voss says. "The hope is that a lot of people will then keep it up because those benefits to the brain are temporary. Understanding exactly how long the benefits last after a single session, and why some benefit more than others, are exciting directions for future research."
The participants also engaged in regular exercise, pedaling on a stationary bike for 50 minutes three times a week for three months. One group engaged in moderate-intensity pedaling, while another group had a mostly lighter workout in which the bike pedals moved for them.
Most individuals in the moderate and lighter-intensity groups showed mental benefits, judging by the brain scans and working memory tests given at the beginning and at the end of the three-month exercise period. But the brain gains were no greater than the improvements from when they had exercised a single time.
"The result that a single session of aerobic exercise mimics the effects of 12 weeks of training on performance has important implications both practically and theoretically," the authors write.
The researchers note their study had a small participant pool, with a homogenous population that excluded anyone with chronic health conditions or who were taking beta-blockers.
To address those limitations, Voss has expanded her participant pool in a current, five-year study to confirm the initial findings and learn more about how exercise alters older people's brains. The participants are healthy older individuals who are not physically active, similar to the participants' profile in the study's results reported here.
The National Institute on Aging, part of the National Institutes of Health, funded the research.
https://www.sciencedaily.com/releases/2019/08/190826110409.htm
Morning exercise can improve decision-making across the day in older adults
Study shows how simple changes to your daily routine is key to good brain health
April 29, 2019
Science Daily/Baker Heart and Diabetes Institute
A study of older Australians has found a morning bout of moderate-intensity exercise improves cognitive performance like decision-making across the day compared to prolonged sitting without exercise.
Furthermore, the study showed that a morning bout of exercise combined with brief light-intensity walking breaks to frequently disrupt sitting throughout an 8-hour day can boost your short-term memory compared to uninterrupted sitting, according to the study published in the British Journal of Sports Medicine.
The 'Brain Breaks' study, led by the Baker Heart and Diabetes Institute and The University of Western Australia, also shows that the distinct responses in cognitive performance to exercise versus exercise and sitting breaks point to different patterns of physical activity being able to enhance distinct aspects of cognition.
The study of more than 65 males and females aged 55 -- 80 years examined the effects of acute morning exercise on a treadmill with and without brief 3 minute walking breaks during an 8-hour day of prolonged sitting, and assessed aspects of cognition and concentration including psychomotor function; attention; executive function such as decision-making; visual learning and working memory.
Central to mediating the benefits of exercise on learning and memory is brain-derived neurotropic growth factor, a protein which plays an important role in the survival and growth of information-transmitting neurons in the brain. The results demonstrated that this protein was elevated for 8 hours during both exercise conditions, relative to prolonged sitting.
Physical activity researcher, Michael Wheeler says the study highlights that uninterrupted sitting should be avoided to maintain optimal cognition across the day, and that moderate-intensity exercise such as a brisk walk should be encouraged for the daily maintenance of brain health.
He says the study also reveals that not all aspects of cognition respond in the same way to a given dose of exercise and that it may be possible to manipulate the pattern of activity across the day to optimise specific cognitive outcomes.
"With an ageing population which is looking to live healthier for longer, these studies are critical to people enjoying a productive and satisfying quality of life," Wheeler says.
"This study highlights how relatively simple changes to your daily routine could have a significant benefit to your cognitive health. It also reveals that one day we may be able to do specific types of exercise to enhance specific cognitive skills such as memory or learning."
https://www.sciencedaily.com/releases/2019/04/190429154529.htm
Exercise activates memory neural networks in older adults
Study shows acute exercise has the ability to impact brain regions important to memory
April 25, 2019
Science Daily/University of Maryland
How quickly do we experience the benefits of exercise? A new University of Maryland study of healthy older adults shows that just one session of exercise increased activation in the brain circuits associated with memory -- including the hippocampus -- which shrinks with age and is the brain region attacked first in Alzheimer's disease.
"While it has been shown that regular exercise can increase the volume of the hippocampus, our study provides new information that acute exercise has the ability to impact this important brain region," said Dr. J. Carson Smith, an associate professor of kinesiology in the University of Maryland School of Public Health and the study's lead author.
The study is published in the Journal of the International Neuropsychological Society.
Dr. Smith's research team measured the brain activity (using fMRI) of healthy participants ages 55-85 who were asked to perform a memory task that involves identifying famous names and non famous ones. The action of remembering famous names activates a neural network related to semantic memory, which is known to deteriorate over time with memory loss.
This test was conducted 30 minutes after a session of moderately intense exercise (70% of max effort) on an exercise bike and on a separate day after a period of rest. Participants' brain activation while correctly remembering names was significantly greater in four brain cortical regions (including the middle frontal gyrus, inferior temporal gryus, middle temporal gyrus, and fusiform gyrus) after exercise compared to after rest. The increased activation of the hippocampus was also seen on both sides of the brain.
"Just like a muscle adapts to repeated use, single sessions of exercise may flex cognitive neural networks in ways that promote adaptations over time and lend to increased network integrity and function and allow more efficient access to memories," Dr. Smith explained.
https://www.sciencedaily.com/releases/2019/04/190425104310.htm
Exercise may lessen fall risk for older adults with Alzheimer's
Study indicates exercise may decrease risk of falling for older adults who have Alzheimer's disease and mental health challenges
October 29, 2018
Science Daily/American Geriatrics Society
A research team decided to explore whether exercise could reduce the risk of falling among community-dwelling people with Alzheimer's Disease who also had neuropsychiatric symptoms.
Alzheimer's disease (AD) is a brain disease that causes changes that kill brain cells. AD is a type of dementia, which causes memory loss and problems with thinking and making decisions. People with AD and other forms of dementia have difficulties performing the daily activities others might consider routine.
Dementia takes a toll on those who live with it -- and it also places a burden on caregivers. Along with problems connected to memory, language, and decision-making, dementia can cause neuropsychiatric symptoms, such as depression, anxiety, changes in mood, increased irritability, and changes in personality and behavior. People who have AD/dementia also have twice the risk for falls compared to people without dementia. About 60 percent of older adults with dementia fall each year.
Researchers suggest that having neuropsychiatric symptoms might predict whether an older person with AD/dementia is more likely to have a fall. We also know that exercise can reduce the number of falls in older adults with dementia. However, we don't know very much about how neuropsychiatric symptoms may increase the risk of falls, and we know even less about how exercise may reduce the risk of falls for people with dementia and neuropsychiatric symptoms. A research team decided to explore whether exercise could reduce the risk of falling among community-dwelling people with AD who also had neuropsychiatric symptoms.
To learn more, the researchers reviewed a study that investigated the effects of an exercise program for older adults with AD (the FINALEX trial). The study included a range of people living with different stages of AD/dementia and with neuropsychiatric symptoms. Their findings were published in the Journal of the American Geriatrics Society.
The original FINALEX study examined and compared older adults who had home- or group-based exercise training with people who didn't exercise but who received regular care. The researchers learned that the people who exercised had a lower risk for falls than those who didn't exercise. There was also a higher risk for falls among those who had lower scores on psychological tests and who didn't exercise.
This study revealed that people with AD/dementia and neuropsychiatric symptoms such as depression and anxiety have a higher risk for falls. Exercise can reduce the risk of falling for older adults with these symptoms. Further studies are needed to confirm these results.
https://www.sciencedaily.com/releases/2018/10/181029135235.htm
High-intensity exercise boosts memory, new research suggests
November 22, 2017
Science Daily/McMaster University
The health advantages of high-intensity exercise are widely known but new research points to another major benefit: better memory. The findings could have implications for an aging population which is grappling with the growing problem of catastrophic diseases such as dementia and Alzheimer's.
The findings could have implications for an aging population which is grappling with the growing problem of catastrophic diseases such as dementia and Alzheimer's.
Scientists have found that six weeks of intense exercise -- short bouts of interval training over the course of 20 minutes -- showed significant improvements in what is known as high-interference memory, which, for example, allows us to distinguish our car from another of the same make and model.
The study is published in the Journal of Cognitive Neuroscience.
The findings are important because memory performance of the study participants, who were all healthy young adults, increased over a relatively short period of time, say researchers.
They also found that participants who experienced greater fitness gains also experienced greater increases in brain-derived neurotrophic factor (BDNF), a protein that supports the growth, function and survival of brain cells.
"Improvements in this type of memory from exercise might help to explain the previously established link between aerobic exercise and better academic performance," says Jennifer Heisz, an assistant professor in the Department of Kinesiology at McMaster and lead author of the study.
"At the other end of our lifespan, as we reach our senior years, we might expect to see even greater benefits in individuals with memory impairment brought on by conditions such as dementia," she says.
For the study, 95 participants completed six weeks of exercise training, combined exercise and cognitive training or no training (the control group which did neither and remained sedentary). Both the exercise and combined training groups improved performance on a high-interference memory task, while the control group did not.
Researchers measured changes in aerobic fitness, memory and neurotrophic factor, before and after the study protocol.
The results reveal a potential mechanism for how exercise and cognitive training may be changing the brain to support cognition, suggesting that the two work together through complementary pathways of the brain to improve high-interference memory.
Researchers have begun to examine older adults to determine if they will experience the same positive results with the combination of exercise and cognitive training.
"One hypothesis is that we will see greater benefits for older adults given that this type of memory declines with age," says Heisz. "However, the availability of neurotrophic factors also declines with age and this may mean that we do not get the synergistic effects."
https://www.sciencedaily.com/releases/2017/11/171122103555.htm