Everyday activities associated with more gray matter in brains of older adults
Study measured amount of lifestyle physical activity such as house work, dog walking and gardening
February 14, 2018
Science Daily/Rush University Medical Center
Higher levels of lifestyle physical activity are associated with more gray matter in the brains of older adults, according to a new study.
The gray matter in the brain includes regions responsible for controlling muscle movement, experiencing the senses, thinking and feeling, memory and speech and more. The volume of gray matter is a measure of brain health, but the amount of gray matter in the brain often begins to decrease in late adulthood, even before symptoms of cognitive dysfunction appear.
"More gray matter is associated with better cognitive function, while decreases in gray matter are associated with Alzheimer's disease and other related dementias," said Shannon Halloway, PhD, the lead author of the Journal of Gerontology paper and the Kellogg/Golden Lamp Society Postdoctoral Fellow in the Rush University College of Nursing. "A healthy lifestyle, such as participating in lifestyle physical activity, is beneficial for brain health, and may help lessen gray matter atrophy (decreases)."
Study used accelerometer to measure activity of 262 older adults
The study measured the levels of lifestyle physical activity by 262 older adults in Rush's Memory and Aging Project, an ongoing epidemiological cohort study. Participants are recruited from retirement communities and subsidized housing facilities in and around Chicago to participate in annual clinical evaluations and magnetic resonance imaging (MRI) scans, and to donate their brains and other parts of their bodies for research after their deaths.
Participants in the lifestyle study wore a non-invasive device called an accelerometer continuously for seven to ten days. The goal was to accurately measure the frequency, duration and intensity of a participant's activities over that time.
Lifestyle physical activity is "more realistic for older adults" than a structured exercise program that might require them to go to a gym, according to Halloway.
"Accessibility becomes an issue as one ages," Halloway said. "Transportation can be a problem. Gym settings can be intimidating for any individual, but especially so for older adults."
Accelerometers provide more precise measures of activity
The use of accelerometers was only one of the ways in which this analysis differed from some other investigations of the health of older people. Most research that explores the effects of exercise relies on questionnaires, which ask participants to "self-report" their levels of activity, Halloway said. She added that questionnaires tend to ask in a fairly non-specific fashion about types and intensity of exercise.
The real problem with questionnaires, though, is that "sometimes, we get really inaccurate reports of activity," Halloway acknowledged. "People commonly over-estimate, and on the flip side, some underestimate the lifestyle activity they're getting from things they don't consider exercise, like household chores, for example."
As to the accelerometer, she says, "it's not as commonly used (in studies of exercise) as we would like," even though accelerometers provide more precise results than self-reporting.
Study provided insights into activity levels of people past 80
Another departure in Halloway's study from some other investigations was the opportunity she had to assess the effects of exercise on individuals older than 80. In fact, the mean age in this study was 81 years, compared with 70 years for other studies Halloway used as a reference.
"One great strength of the Rush Alzheimer's Disease Center is its amazing ability to follow up with participants, and its high retention rates of participants," Halloway says. As a result, the Memory and Aging Project captures a number of participants in that older age group.
However, no one was included in Halloway's analysis who had a diagnosis or symptoms of dementia, or even mild cognitive impairment; a history of brain surgery; or brain abnormalities such as tumors, as seen on MRIs.
The study compared gray matter volumes as seen in participants' MRIs with readings from the accelerometers and other data, which all were obtained during the same year. Halloway's analysis found the association between participants' actual physical activity and gray matter volumes remained after further controlling for age, gender, education levels, body mass index and symptoms of depression, all of which are associated with lower levels of gray matter in the brain.
"Our daily lifestyle physical activities are supportive of brain health, and adults of all ages should continue to try and increase lifestyle physical activity to gain these benefits," Halloway said. "Moving forward, our goal is to develop and test behavioral interventions that focus on lifestyle physical activity for older adults at increased risk for cognitive decline due to cardiovascular disease,"
https://www.sciencedaily.com/releases/2018/02/180214093828.htm
Running helps brain stave off effects of chronic stress
Exercise protects vital memory and learning functions
February 14, 2018
Science Daily/Brigham Young University
The study finds that running mitigates the negative impacts chronic stress has on the hippocampus, the part of the brain responsible for learning and memory.
Most people agree that getting a little exercise helps when dealing with stress. A new BYU study discovers exercise -- particularly running -- while under stress also helps protect your memory.
The study, newly published in the journal of Neurobiology of Learning and Memory, finds that running mitigates the negative impacts chronic stress has on the hippocampus, the part of the brain responsible for learning and memory.
"Exercise is a simple and cost-effective way to eliminate the negative impacts on memory of chronic stress," said study lead author Jeff Edwards, associate professor of physiology and developmental biology at BYU.
Inside the hippocampus, memory formation and recall occur optimally when the synapses or connections between neurons are strengthened over time. That process of synaptic strengthening is called long-term potentiation (LTP). Chronic or prolonged stress weakens the synapses, which decreases LTP and ultimately impacts memory. Edwards' study found that when exercise co-occurs with stress, LTP levels are not decreased, but remain normal.
To learn this, Edwards carried out experiments with mice. One group of mice used running wheels over a 4-week period (averaging 5 km ran per day) while another set of mice was left sedentary. Half of each group was then exposed to stress-inducing situations, such as walking on an elevated platform or swimming in cold water. One hour after stress induction researchers carried out electrophysiology experiments on the animals' brains to measure the LTP.
Stressed mice who had exercised had significantly greater LTP than the stressed mice who did not run. Edwards and his colleagues also found that stressed mice who exercised performed just as well as non-stressed mice who exercised on a maze-running experiment testing their memory. Additionally, Edwards found exercising mice made significantly fewer memory errors in the maze than the sedentary mice.
The findings reveal exercise is a viable method to protect learning and memory mechanisms from the negative cognitive impacts of chronic stress on the brain.
"The ideal situation for improving learning and memory would be to experience no stress and to exercise," Edwards said. "Of course, we can't always control stress in our lives, but we can control how much we exercise. It's empowering to know that we can combat the negative impacts of stress on our brains just by getting out and running."
https://www.sciencedaily.com/releases/2018/02/180214093823.htm
Caffeine’s sport performance advantage for infrequent tea and coffee drinkers
January 19, 2018
Dublin City University
Sports scientists have found that the performance enhancing benefits of caffeine are more apparent in athletes who do not drink caffeine-rich drinks such as tea, coffee, and energy drinks on a daily basis.
Researchers Dr Brendan Egan and Mark Evans from the DCU School of Health and Human Performance examined the impact of caffeine, in the form of caffeinated chewing gum, on the performance of 18 male team sport athletes during a series of repeated sprints. The athletes undertook 10 repeated sprints under conditions with and without two sticks of the caffeinated gum, which is equivalent to two strong cups of coffee.
They found that the caffeinated gum provided very little advantage to athletes whose bodies may have become desensitised to caffeine through a process called habituation, which occurs by having caffeine frequently.
However, the athletes who had a low habitual caffeine consumption maintained their performance in repeated sprint tests after ingesting a caffeinated chewing gum, while the performance of athletes who consumed the caffeine equivalent of three or more cups of coffee per day worsened over the course of the ten repeated sprints. This indicated that this second group did not benefit from caffeine as a performance aid.
Caffeine is regarded as one of the most popular performance enhancing supplements among athletes. Its benefits include improved muscle strength, mental alertness, as well as reducing the perception of effort during intense activity, therefore helping athletes to perform faster and longer.
The findings from the DCU-led study were published in the International Journal of Sport Nutrition and Exercise Metabolism. They recommended that athletes who consume caffeine on a regular basis should reduce their consumption in the lead-up to a big performance, if they want to receive the benefits of a caffeine supplement as a performance aid.
https://www.sciencedaily.com/releases/2018/01/180119090348.htm
Don’t like going to the gym? It could be your personality
January 10, 2018
Science Daily/British Psychological Society (BPS)
The effectiveness of someone’s exercise regime may depend on their individual personality type, with more creative people better suited to outdoor activities.
That is the key finding of research being presented today, Thursday 11 January, by John Hackston, Chartered Psychologist and Head of Thought Leadership at OPP, at the British Psychological Society's annual conference of the Division of Occupational Psychology in Stratford-upon-Avon.
John Hackston said:
"We were keen to investigate how organisations could help their staff's development through exercise, finding that matching an individual's personality type to a particular type of exercise can increase both the effectiveness and the person's enjoyment of it."
More than 800 people from a range of businesses across several countries were surveyed for the study, which found that people with extraverted personality types were more likely to prefer exercising at the gym.
Staff with a preference for objective logic were also more likely to stick with a regimented exercise plan than those who view feelings and values as being more important.
More creatively minded staff, particularly those who enjoy working with new ideas, were much better suited to outdoor activities such as cycling and running when compared to a structured gym regime.
John Hackston added:
"The most important piece of advice to come out of this research is that there is not one type of exercise that is suited to everyone.
"There can be pressure to follow the crowd to the gym or sign up to the latest exercise fad, but it would be much more effective for them to match their personality type to an exercise plan that is more likely to last the test of time.
"Organisations can help their staff to improve their fitness using this research, with increased fitness potentially leading to lower illness-related absences and increased employee satisfaction."
https://www.sciencedaily.com/releases/2018/01/180110223412.htm
Try exercise to improve memory and thinking, new guideline urges
December 28, 2017
Science Daily/Mayo Clinic
For patients with mild cognitive impairment, don't be surprised if your health care provider prescribes exercise rather than medication. A new guideline for medical practitioners says they should recommend twice-weekly exercise to people with mild cognitive impairment to improve memory and thinking.
The recommendation is part of an updated guideline for mild cognitive impairment published in the Dec. 27 online issue of Neurology, the medical journal of the American Academy of Neurology.
"Regular physical exercise has long been shown to have heart health benefits, and now we can say exercise also may help improve memory for people with mild cognitive impairment," says Ronald Petersen, M.D., Ph.D., lead author, director of the Alzheimer's Disease Research Center, Mayo Clinic, and the Mayo Clinic Study of Aging. "What's good for your heart can be good for your brain." Dr. Petersen is the Cora Kanow Professor of Alzheimer's Disease Research.
Mild cognitive impairment is an intermediate stage between the expected cognitive decline of normal aging and the more serious decline of dementia. Symptoms can involve problems with memory, language, thinking and judgment that are greater than normal age-related changes.
Generally, these changes aren't severe enough to significantly interfere with day-to-day life and usual activities. However, mild cognitive impairment may increase the risk of later progressing to dementia caused by Alzheimer's disease or other neurological conditions. But some people with mild cognitive impairment never get worse, and a few eventually get better.
The academy's guideline authors developed the updated recommendations on mild cognitive impairment after reviewing all available studies. Six-month studies showed twice-weekly workouts may help people with mild cognitive impairment as part of an overall approach to managing their symptoms.
Dr. Petersen encourages people to do aerobic exercise: Walk briskly, jog, whatever you like to do, for 150 minutes a week -- 30 minutes, five times or 50 minutes, three times. The level of exertion should be enough to work up a bit of a sweat but doesn't need to be so rigorous that you can't hold a conversation. "Exercising might slow down the rate at which you would progress from mild cognitive impairment to dementia," he says.
Another guideline update says clinicians may recommend cognitive training for people with mild cognitive impairment. Cognitive training uses repetitive memory and reasoning exercises that may be computer-assisted or done in person individually or in small groups. There is weak evidence that cognitive training may improve measures of cognitive function, the guideline notes.
The guideline did not recommend dietary changes or medications. There are no drugs for mild cognitive impairment approved by the U.S. Food and Drug Administration.
More than 6 percent of people in their 60s have mild cognitive impairment across the globe, and the condition becomes more common with age, according to the American Academy of Neurology. More than 37 percent of people 85 and older have it.
With such prevalence, finding lifestyle factors that may slow down the rate of cognitive impairment can make a big difference to individuals and society, Dr. Petersen notes.
"We need not look at aging as a passive process; we can do something about the course of our aging," he says. "So if I'm destined to become cognitively impaired at age 72, I can exercise and push that back to 75 or 78. That's a big deal."
The guideline, endorsed by the Alzheimer's Association, updates a 2001 academy recommendation on mild cognitive impairment. Dr. Petersen was involved in the development of the first clinical trial for mild cognitive impairment and continues as a worldwide leader researching this stage of disease when symptoms possibly could be stopped or reversed.
https://www.sciencedaily.com/releases/2017/12/171228145026.htm
Short-term exercise equals big-time brain boost
Even a one-time, brief burst of exercise can improve focus, problem-solving
December 21, 2017
Science Daily/University of Western Ontario
A 10-minute, one-time burst of exercise can measurably boost your brain power, at least temporarily, researchers at Western University in London, Canada, have found.
While other studies have showed brain-health benefits after 20-minutes of a single-bout of exercise, or following commitment to a long-term (24-week) exercise program, this research suggests even 10 minutes of aerobic activity can prime the parts of the brain that help us problem-solve and focus.
"Some people can't commit to a long-term exercise regime because of time or physical capacity," said Kinesiology Prof. Matthew Heath, who is also a supervisor in the Graduate Program in Neuroscience and, with master's student Ashna Samani, conducted the study. "This shows that people can cycle or walk briskly for a short duration, even once, and find immediate benefits."
During the study, research participants either sat and read a magazine or did 10 minutes of moderate-to-vigorous exercise on a stationary bicycle. Following the reading and exercise session, the researchers used eye-tracking equipment to examine participants' reaction times to a cognitively demanding eye movement task. The task was designed to challenge areas of the brain responsible for executive function such as decision-making and inhibition.
"Those who had exercised showed immediate improvement. Their responses were more accurate and their reaction times were up to 50 milliseconds shorter than their pre-exercise values. That may seem minuscule but it represented a 14-per-cent gain in cognitive performance in some instances," said Heath, who is also an associate member of Western's Brain and Mind institute. He is conducting a study now to determine how long the benefits may last following exercise.
The work has significance for older people in early stages of dementia who may be less mobile, he said, and for anyone else looking to gain quick a mental edge in their work.
"I always tell my students before they write a test or an exam or go into an interview -- or do anything that is cognitively demanding -- they should get some exercise first," Heath said. "Our study shows the brain's networks like it. They perform better.
https://www.sciencedaily.com/releases/2017/12/171221122543.htm
Working memory positively associated with higher physical endurance, better cognitive function
Suboptimal cardiovascular health, smoking are associated with less cohesive brain network
December 5, 2017
Science Daily/The Mount Sinai Hospital / Mount Sinai School of Medicine
A positive relationship has been found between the brain network associated with working memory -- the ability to store and process information relevant to the task at hand -- and healthy traits such as higher physical endurance and better cognitive function
These traits were associated with greater cohesiveness of the working memory brain network while traits indicating suboptimal cardiovascular and metabolic health, and suboptimal health habits including binge drinking and regular smoking, were associated with less cohesive working memory networks.
This is the first study to establish the link between working memory and physical health and lifestyle choices.
The results of the study will be published online in Molecular Psychiatry.
The research team took brain scans of 823 participants in the Human Connectome Project (HCP), a large brain imaging study funded by the National Institutes of Health, while they performed a task involving working memory, and extracted measures of brain activity and connectivity to create a brain map of working memory. The team then used a statistical method called sparse canonical correlation to discover the relationships between the working memory brain map and 116 measures of cognitive ability, physical and mental health, personality, and lifestyle choices. They found that cohesiveness in the working memory brain map was positively associated with higher physical endurance and better cognitive function. Physical traits such as high body mass index, and suboptimal lifestyle choices including binge alcohol drinking and regular smoking, had the opposite association.
"Working memory accounts for individual differences in personal, educational, and professional attainment," said Sophia Frangou, MD, PhD, Professor of Psychiatry at the Icahn School of Medicine at Mount Sinai. "Working memory is also one of the brain functions that is severely affected by physical and mental illnesses. Our study identified factors that can either support or undermine the working memory brain network. Our findings can empower people to make informed choices about how best to promote and preserve brain health."
https://www.sciencedaily.com/releases/2017/12/171205091531.htm
Exercise increases brain size
November 13, 2017
Science Daily/NICM, Western Sydney University
Aerobic exercise can improve memory function and maintain brain health as we age, a new study has found.
In a first of its kind international collaboration, researchers from Australia's National Institute of Complementary Medicine at Western Sydney University and the Division of Psychology and Mental Health at the University of Manchester in the UK examined the effects of aerobic exercise on a region of the brain called the hippocampus, which is critical for memory and other brain functions.
Brain health decreases with age, with the average brain shrinking by approximately five per cent per decade after the age of 40.
Studies in mice and rats have consistently shown that physical exercise increases the size of the hippocampus but until now evidence in humans has been inconsistent.
The researchers systematically reviewed 14 clinical trials which examined the brain scans of 737 people before and after aerobic exercise programs or in control conditions.
The participants included a mix of healthy adults, people with mild cognitive impairment such as Alzheimer's and people with a clinical diagnosis of mental illness including depression and schizophrenia. Ages ranged from 24 to 76 years with an average age of 66.
The researchers examined effects of aerobic exercise, including stationary cycling, walking, and treadmill running. The length of the interventions ranged from three to 24 months with a range of 2-5 sessions per week.
Overall, the results -- published in the journal NeuroImage -- showed that, while exercise had no effect on total hippocampal volume, it did significantly increase the size of the left region of the hippocampus in humans.
Lead author, NICM postdoctoral research fellow, Joseph Firth said the study provides some of the most definitive evidence to date on the benefits of exercise for brain health.
"When you exercise you produce a chemical called brain-derived neurotrophic factor (BDNF), which may help to prevent age-related decline by reducing the deterioration of the brain," Mr Firth said.
"Our data showed that, rather than actually increasing the size of the hippocampus per se, the main 'brain benefits' are due to aerobic exercise slowing down the deterioration in brain size. In other words, exercise can be seen as a maintenance program for the brain."
Mr Firth said along with improving regular 'healthy' ageing, the results have implications for the prevention of ageing-related neurodegenerative disorders such as Alzheimer's and dementia -- however further research is needed to establish this.
Interestingly, physical exercise is one of the very few 'proven' methods for maintaining brain size and functioning into older age.
https://www.sciencedaily.com/releases/2017/11/171113195024.htm
Should exercise be what the doctor orders for depression?
November 8, 2017
Science Daily/Michigan State University
More mental health providers may want to take a closer look at including exercise in their patients' treatment plans, a new study suggests. Researchers asked 295 patients receiving treatment at a mental health clinic whether they wanted to be more physically active and if exercise helped improve their mood and anxiety. They also asked if patients wanted their therapist to help them become more active.
Michigan State University and University of Michigan researchers asked 295 patients receiving treatment at a mental health clinic whether they wanted to be more physically active and if exercise helped improve their mood and anxiety. They also asked if patients wanted their therapist to help them become more active.
Eighty-five percent said they wanted to exercise more and over 80 percent believed exercise helped improve their moods and anxiety much of the time. Almost half expressed interest in a one-time discussion, with many participants also wanting ongoing advice about physical activity with their mental health provider.
The study is now published in the journal General Hospital Psychiatry.
"Physical activity has been shown to be effective in alleviating mild to moderate depression and anxiety," said Carol Janney, lead author of the study and an MSU assistant professor of epidemiology. "Current physical activity guidelines advise at least 30 minutes, five days a week to promote mental and physical health, yet many of those surveyed weren't meeting these recommendations."
More than half of the participants said their mood limited their ability to exercise, which Janney said provides an opportunity for physicians and therapists in clinics to offer additional support.
"Offering physical activity programs inside the mental health clinics may be one of many patient-centered approaches that can improve the mental and physical health of patients," Janney said.
Marcia Valenstein, senior author and professor emeritus in psychiatry at U-M, agreed.
"Mental health treatment programs need to partner with fitness programs to support their patients' willingness to exercise more," she said. "This support might come from integrating personal trainers into mental health clinics or having strong partnerships with the YMCA or other community recreational facilities."
Both Valenstein and Janney said that psychiatrists and other providers might discuss with patients the general need to exercise, but few actually sit down with patients and create a comprehensive exercise plan for them or regularly make sure they are adhering to a specific goal.
"Mental health providers such as psychiatrists and therapists may not have the necessary training to prescribe physical activity as part of their mental health practice," Janney said. "But by teaming up with certified personal trainers or other exercise programs, it may help them prescribe or offer more recommendations for physical activity in the clinic setting."
Results also showed that over half of the patients surveyed showed interest in getting help from a personal trainer and were willing to pay a bit extra, but that the topic of physical activity was rarely discussed by their physician.
"This is a missed opportunity," Valenstein said. "If we can make it easier for both therapists and their patients to have easier access to physical activity services, then we are likely to help more patients reduce their depression and anxiety."
Once the effectiveness of this approach is proven, she added, health insurers might consider moving in the direction of covering services that help people exercise.
"Several insurers already do this for diabetes prevention, so it's not out of the question."
https://www.sciencedaily.com/releases/2017/11/171108151604.htm
Group exercise improves quality of life, reduces stress far more than individual work outs
October 30, 2017
Science Daily/American Osteopathic Association
Group exercise participants showed significant improvements in all three quality of life measures: mental (12.6 percent), physical (24.8 percent) and emotional (26 percent). They also reported a 26.2 percent reduction in perceived stress levels. By comparison, individual fitness participants on average worked out twice as long, and saw no significant changes in any measure, except in mental quality of life (11 percent increase).
Researchers found working out in a group lowers stress by 26 percent and significantly improves quality of life, while those who exercise individually put in more effort but experienced no significant changes in their stress level and a limited improvement to quality of life, according to a study published in The Journal of the American Osteopathic Association.
"The communal benefits of coming together with friends and colleagues, and doing something difficult, while encouraging one another, pays dividends beyond exercising alone," said Dayna Yorks, DO, lead researcher on this study. "The findings support the concept of a mental, physical and emotional approach to health that is necessary for student doctors and physicians."
Dr. Yorks and her fellow researchers at the University of New England College of Osteopathic Medicine recruited 69 medical students -- a group known for high levels of stress and self-reported low quality of life -- and allowed them to self-select into a twelve-week exercise program, either within a group setting or as individuals. A control group abstained from exercise other than walking or biking as a means of transportation.
Every four weeks, participants completed a survey asking them to rate their levels of perceived stress and quality of life in three categories: mental, physical and emotional.
Those participating in group exercise spent 30 minutes at least once a week in CXWORX, a core strengthening and functional fitness training program. At the end of the twelve weeks, their mean monthly survey scores showed significant improvements in all three quality of life measures: mental (12.6 percent), physical (24.8 percent) and emotional (26 percent). They also reported a 26.2 percent reduction in perceived stress levels.
By comparison, individual fitness participants were allowed to maintain any exercise regimen they preferred, which could include activities like running and weight lifting, but they had to work out alone or with no more than two partners. On average the solitary exercisers worked out twice as long, and saw no significant changes in any measure, except in mental quality of life (11 percent increase). Similarly, the control group saw no significant changes in quality of life or perceived stress.
"Medical schools understand their programs are demanding and stressful. Given this data on the positive impact group fitness can have, schools should consider offering group fitness opportunities," said Dr. Yorks. "Giving students an outlet to help them manage stress and feel better mentally and physically can potentially alleviate some of the burnout and anxiety in the profession."
https://www.sciencedaily.com/releases/2017/10/171030092917.htm
'Selfish brain' wins out when competing with muscle power
October 20, 2017
Science Daily/University of Cambridge
New research on our internal trade-off when physical and mental performance are put in direct competition has found that cognition takes less of a hit, suggesting more energy is diverted to the brain than body muscle. Researchers say the findings support the 'selfish brain' theory of human evolution.
Human brains are expensive -- metabolically speaking. It takes lot of energy to run our sophisticated grey matter, and that comes at an evolutionary cost.
Now, a new investigation into the immediate trade-off that occurs inside us when we have to think fast and work hard at the same time is the first to demonstrate that -- while both are impaired -- our mental ability is less affected than our physical capacity.
Researchers say that the findings suggest a "preferential allocation of glucose to the brain," which they argue is likely to be an evolved trait -- as prioritising quick thinking over fast moving, for example, may have helped our species survive and thrive.
Scientists from the University of Cambridge's PAVE (Phenotypic Adaptability, Variation and Evolution) research group tested 62 male students drawn from the University's elite rowing crews. The participants had an average age of 21.
The rowers performed two separate tasks: one memory, a three minute word recall test, and one physical, a three minute power test on a rowing machine.
They then performed both tasks at once, with individual scores compared to those from previous tests. As expected, the challenge of rowing and remembering at the same time reduced both physical and mental performance.
However, the research team found that change in recall was significantly less than the change in power output.
During the simultaneous challenge, recall fell by an average of 9.7%, while power fell by an average of 12.6%. Across all participants the drop in physical power was on average 29.8% greater than drop in cognitive function.
The team say the results of their new study, published today in the journal Scientific Reports, add evidence to the 'selfish brain' hypothesis: that the brain has evolved to prioritise its own energy needs over those of peripheral organs, such as skeletal muscle.
"A well-fuelled brain may have offered us better survival odds than well-fuelled muscles when facing an environmental challenge," said Dr Danny Longman, the study's lead author from the PAVE team in Cambridge's Department of Archaeology.
"The development of an enlarged and elaborated brain is considered a defining characteristic of human evolution, but one that has come as a result of trade-offs.
"At the evolutionary level, our brains have arguably cost us decreased investment in muscle as well as a shrunken digestive system.
"Developmentally, human babies have more stored fat than other mammals, acting as an energy buffer that feeds our high cerebral requirements.
"On an acute level, we have now demonstrated that when humans simultaneously experience extremes of physical and mental exertion, our internal trade-off preserves cognitive function as the body's priority."
The adult brain derives its energy almost exclusively from the metabolism of glucose. Yet skeletal muscle mass is also energetically expensive tissue, accounting for 20% of the human male 'basal metabolic rate' -- the energy used when doing nothing.
Longman says a limited supply of blood glucose and oxygen means that, when active, skeletal muscle becomes a "powerful competitor" to the brain. "This is the potential mechanism for the fast-acting trade-off in brain and muscle function we see in just a three minute window."
"Trade-offs between organs and tissues allow many organisms to endure conditions of energy deficit through internal prioritising. However, this comes at a cost," said Longman.
He points to examples of this trade-off in humans benefiting the brain. "The selfish nature of the brain has been observed in the unique preservation of brain mass as bodies waste away in people suffering from long-term malnutrition or starvation, as well as in children born with growth restriction."
Study details:
Protocol A -- isolated power test: Participants rowed at maximal effort for 3 minutes, and their average Wattage was recorded.
Protocol B -- isolated recall test: Participants performed a free recall word task in which they were shown 75 words from the Toronto Word Pool for a 3 minute period. They then had 5 minutes to recall and write as many words as possible. The number of words correctly recalled during a given time period was recorded.
Protocol C -- combined 'trade-off' test: Participants did both (but with a different word set), and their average Wattage and number of words correctly recalled was recorded. Researchers used 'paired samples t-tests' to compare power output between Protocols A and C, and for comparing free recall in Protocols B and C. They then compared the two differences, and found that the percentage change in free recall was significantly less than the percentage change in power output -- an average of 29.8%.
https://www.sciencedaily.com/releases/2017/10/171020092221.htm
Brain stimulation can improve athletic performance
Research into the effects of brain stimulation on athletes' performance has demonstrated that it is an effective way to improve endurance
October 12, 2017
Science Daily/University of Kent
Research into the effects of brain stimulation on athletes' performance has demonstrated that it is an effective way to improve endurance. The findings are expected to advance understanding of the brain's role in endurance exercise, how it can alter the physical limits of performance in healthy people and add evidence to the debate on the use of legal methods to enhance performance in competition.
The findings are expected to advance our understanding of the brain's role in endurance exercise, how it can alter the physical limits of performance in healthy people and add further evidence to the debate on the use of legal methods to enhance performance in competition.
The research, which was conducted by Dr Lex Mauger and colleagues at Kent's School of Sport and Exercise Sciences (SSES), set out to investigate how endurance limits are a matter for the mind as well as the body.
By testing cycling time to task failure (TTF) in a group of 12 active participants in a placebo controlled study, Dr Mauger discovered that stimulating the brain by passing a mild electrical current (transcranial direct current stimulation or tDCS) over the scalp to stimulate it increased the activity of the area associated with muscle contraction. This decreased perception of effort and increased the length of time participants could cycle for.
The team explained this is because the exercise felt less effortful following stimulation. tDCS has been used to enhance endurance performance but how it achieved this was previously unknown and this study has helped identify the mechanisms.
Bilateral extracephalic transcranial direct current stimulation improves endurance performance in healthy individuals (Dr Luca Angius, Dr Lex Mauger, Dr James Hopker, and Professor Samule Marcora, University of Kent, with Professor Alvaro Pascual-Leone, Berenson-Allen Center for Non-Invasive Brain Stimulation, Division of Cognitive Neurology, Beth Israel Deaconess Medical Center and Dr Emiliano Santarnecch, Harvard Medical School, Boston, MA, USA) is published in the journal Brain Stimulation.
https://www.sciencedaily.com/releases/2017/10/171012122736.htm
Better physical fitness and lower aortic stiffness key to slower brain aging
June 12, 2018
Science Daily/IOS Press
The rate of decline in certain aspects of memory may be explained by a combination of overall physical fitness and the stiffness of the central arteries.
A study to be published in the Journal of Alzheimer's Disease considers the mechanisms underlying cognitive performance in older people living independently. Lead author, PhD candidate Greg Kennedy, says that from early adulthood, memory and other aspects of cognition slowly decline, with an increasing risk of developing into dementia in later life.
"Exactly why this occurs is unclear, but research indicates that exercise and physical fitness are protective," Mr Kennedy says. "A healthier, more elastic aorta is also theorised to protect cognitive function, by reducing the negative effects of excessive blood pressure on the brain."
The study investigated whether fitness was associated with better cognition through a healthier aorta. Physical fitness and arterial stiffness assessment One hundred and two people (73 females and 29 males), aged between 60 and 90 years, living independently in aged care communities, were recruited in Melbourne, Australia.
Their fitness was assessed with the Six-Minute Walk test which involved participants walking back and forth between two markers placed 10 metres apart for six minutes.
Only participants who completed the full six minutes were included in the analysis, which assessed the stiffness of their arteries and cognitive performance.
"People generally are less fit and have stiffer arteries as they age, which seems to explain the difference in memory ability that is usually attributed to 'getting older'," Mr Kennedy says.
Interestingly, physical fitness did not seem to affect central arterial stiffness, however Mr Kennedy points out that only current fitness was assessed -- long term fitness may be a better predictor of central arterial stiffness, however this has yet to be investigated.
"Unfortunately, there is currently no effective pharmacological intervention that has proven effective in the long term in reducing this decline or staving off dementia," Mr Kennedy says.
"The results of this study indicate that remaining as physically fit as possible, and monitoring central arterial health, may well be an important, cost effective way to maintain our memory and other brain functions in older age."
https://www.sciencedaily.com/releases/2018/06/180612092122.htm
Aerobic exercise may mildly delay, slightly improve Alzheimer's symptoms
January 26, 2018
Science Daily/American Geriatrics Society
Geriatrics experts have suggested that exercising can improve brain health in older adults. However, not all studies of exercise and older adults have proven the benefits of exercise. 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.
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.
https://www.sciencedaily.com/releases/2018/01/180126130325.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
Drinking water may help exercising seniors stay mentally sharp
Hydration boosts performance on test of executive function following exercise
April 22, 2018
Science Daily/American Physiological Society
Older people should drink more water to reap the full cognitive benefits of exercise, new research suggests. The study explores the association between hydration status before exercising and exercise-enhanced cognition in older adults.
Dehydration has been shown to impair exercise performance and brain function in young people, but less is known about its impact on older populations. "Middle-age and older adults often display a blunted thirst perception, which places them at risk for dehydration and subsequently may reduce the cognitive health-related benefits of exercise," a team of New England-based researchers wrote.
The researchers recruited recreational cyclists (average age 55) who participated in a large cycling event on a warm day (78-86 degrees F). The cyclists performed a "trail-making" executive function test -- quickly and accurately connecting numbered dots using paper and pencil -- before and after the event. Executive function includes the skills needed to plan, focus, remember and multitask. Exercise has been shown to improve intellectual health, including executive function.
The research team tested the volunteers' urine before they exercised and divided them into two groups -- normal hydration and dehydrated -- based on their hydration status. The normal hydration group showed noticeable improvement in the completion time of the trail-making test after cycling when compared to their pre-cycling test. The dehydration group also completed their post-cycling test more quickly, but the time reduction was not significant. "This suggests that older adults should adopt adequate drinking behaviors to reduce cognitive fatigue and potentially enhance the cognitive benefits of regular exercise participation," the researchers wrote.
https://www.sciencedaily.com/releases/2018/04/180422123757.htm
Exercising at own pace boosts a child’s ability to learn
December 19, 2017
Science Daily/University of Stirling
A child’s attention and memory improves after exercise according to new research.
Researchers found that pupils' best responses to tests came after physical activity that was set at their own pace, as opposed to exhaustive exercise.
The study is part of the BBC Learning's Terrific Scientific campaign -- designed to inspire schoolchildren to pursue a career in science -- and part-funded by the University of Edinburgh and the Physiological Society.
In the sixth investigation of the series, more than 11,000 school pupils across the UK conducted a scientific investigation to discover the impact of taking a short break from the classroom to complete a physical activity on their mood and cognitive abilities.
The study was jointly led by Dr Colin Moran and Dr Naomi Brooks, of the University of Stirling's Faculty of Health Sciences and Sport, and Dr Josie Booth of the University of Edinburgh's Moray House School of Education.
Dr Brooks explained: "Anecdotal evidence suggests that short breaks involving physical activity can boost concentration and happiness in pupils. While this is positive, the evidence is not conclusive and this is what we asked the children to help investigate.
"Ultimately, we found that 15 minutes of self-paced exercise can significantly improve a child's mood, attention and memory -- enhancing their ability to learn."
A total of 11,613 children in the UK signed up to participate in the research -- including 1,536 from Scotland -- and they were asked to answer questions about how happy and awake they were feeling, before completing attention and memory tasks on a computer. Children completed the tasks both before and after they participated in each of three outdoor activities of varying intensities:
· A bleep test: This was the most intense activity, where the children ran in time with bleeps, which got gradually quicker, until they felt close to exhaustion.
· A run/walk activity: This was of intermediate intensity where the children ran or walked at a speed of their own choice for 15 minutes.
· A control activity: This was the least intense activity where the children went outside to sit or stand for 15 minutes. This was used to compare whether physical activity had a greater impact than simply going outside.
In total, more than 7,300 children provided information on at least one of the key measurements, related to mood and cognition, and participants completed 22,349 batches of computer tasks.
Compared to the control, children reported feeling more awake after taking a break and doing exercise for a short time. Both the bleep test and the run/walk made participants feel more awake than the control activity, although they felt most awake after the run/walk.
The children also said they felt better after doing the run/walk but reported no difference in the way they felt after completing the bleep test, compared to the control activity.
Children responded quicker to the attention task after completing the run/walk, compared to the control and bleep test activities, and were better at controlling their responses after doing the run/walk and bleep test than they were after the control activity.
Following the run/walk, children's ability to remember words in sentences improved, while there was no difference between the bleep test and control activity. However, there appeared to be no real difference to their ability to remember shapes.
"Overall, our study concluded that exercising leads to improvements in children's mood and cognition," Dr Moran said.
"In most tasks, participating in a run/walk activity was more beneficial that doing the bleep test, where children should be closer to exhaustion. However, in most cases, doing the bleep test was no different from completing the control activity."
Dr Booth said: "This suggests that children should be encouraged to exercise at their own pace during short breaks from class. This may help children be more ready to learn when they return to the classroom."
"However, they should not be discouraged from doing more vigorous exercise as in most cases the effect of the bleep test was no different from the control activity.
"Importantly, this exercise should be in addition to normal physical education and also at a time when the class teacher thinks the class would benefit the most from a break."
https://www.sciencedaily.com/releases/2017/12/171219092958.htm
Brains of children with a better physical fitness possess a greater volume of gray matter
November 22, 2017
Science Daily/University of Granada
Physical fitness in children may affect their brain structure, which in turn may have an influence on their academic performance, new research indicates.
Researchers from the University of Granada (UGR) have proven, for the first time in history, that physical fitness in children may affect their brain structure, which in turn may have an influence on their academic performance.
More specifically, the researchers have confirmed that physical fitness in children (especially aerobic capacity and motor ability) is associated with a greater volume of gray matter in several cortical and subcortical brain regions.
In particular, aerobic capacity has been associated with greater gray matter volume in frontal regions (premotor cortex and supplementary motor cortex), subcortical regions (hippocampus and caudate nucleus), temporal regions (inferior temporal gyrus and parahippocampal gyrus) and the calcarine cortex. All of those regions are important for the executive function as well as for learning, motor and visual processes.
This study has been published in the Neuroimage journal and is part of the ActiveBrains project, which is a randomized clinical trial involving more than 100 overweight/obese children led by Francisco B. Ortega. Said project is being carried out mainly at the University of Granada's Sport and Health Institute (IMUDS, from its abbreviation in Spanish) and the Mind, Brain and Behavior Research Center (CIMCYC).
"Our work aims at answering questions such as whether the brain of children with better physical fitness is different from that of children with worse physical fitness and if this affects their academic performance," Ortega explains.
"The answer is short and forceful: yes, physical fitness in children is linked in a direct way to important brain structure differences, and such differences are reflected in the children's academic performance."
Besides, the UGR research associates motor ability with a greater gray matter volume in two regions essential for language processing and reading: the inferior frontal gyrus and the superior temporal gyrus. However, muscular strength didn't showed any independent association with gray matter volume in any brain region.
According to Irene Esteban-Cornejo, postdoctoral researcher at the University of Granada and main author of this paper, gray matter volume in the cortical and subcortical regions influenced by physical fitness improves in turn the children's academic performance.
Moreover, "physical fitness is a factor that can be modified through physical exercise, and combining exercises that improve the aerobic capacity and the motor ability would be an effective approach to stimulate brain development and academic performance in overweight/obese children."
This scientific paper means an important contribution to human knowledge which should be taken into account by educational and public health institutions.
"We appeal both to politicians, who make educational laws that are increasingly more focused on instrumental subjects, and to teachers, who are the final link in the chain and teach Physical Education day after day. School is the only entity that gathers every children in a mandatory way for a period of at least 10 years, and as such, it's the ideal context for applying such recommendations," note the researchers.
In their own words, the authors of this study are "at the disposal of educational and public health institutions for talking about possible measures and putting them into action."
https://www.sciencedaily.com/releases/2017/11/171122093024.htm
Heading a soccer ball causes instant changes to the brain
October 23, 2016
Science Daily/University of Stirling
Researchers have explored the true impact of heading a soccer ball, identifying small but significant changes in brain function immediately after routine heading practice.
The study from Scotland's University for Sporting Excellence published in EBioMedicine is the first to detect direct changes in the brain after players are exposed to everyday head impacts, as opposed to clinical brain injuries like concussion.
A group of soccer ball players headed a ball 20 times, fired from a machine designed to simulate the pace and power of a corner kick. Before and after the heading sessions, scientists tested players' brain function and memory.
Increased inhibition in the brain was detected after just a single session of heading. Memory test performance was also reduced by between 41 and 67 per cent, with effects normalising within 24 hours.
Whether the changes to the brain remain temporary after repeated exposure to a soccer ball and the long-term consequences of heading on brain health, are yet to be investigated.
Played by more than 250 million people worldwide, the 'beautiful game' often involves intentional and repeated bursts of heading a ball. In recent years the possible link between brain injury in sport and increased risk of dementia has focussed attention on whether soccer ball heading might lead to long term consequences for brain health.
Cognitive neuroscientist Dr Magdalena Ietswaart from Psychology at the University of Stirling, said: "In light of growing concern about the effects of contact sport on brain health, we wanted to see if our brain reacts instantly to heading a soccer ball. Using a drill most amateur and professional teams would be familiar with, we found there was infact increased inhibition in the brain immediately after heading and that performance on memory tests was reduced significantly.
"Although the changes were temporary, we believe they are significant to brain health, particularly if they happen over and over again as they do in soccer ball heading. With large numbers of people around the world participating in this sport, it is important that they are aware of what is happening inside the brain and the lasting effect this may have."
Dr Angus Hunter, Reader in Exercise Physiology in the Faculty of Health Sciences and Sport, added: "For the first time, sporting bodies and members of the public can see clear evidence of the risks associated with repetitive impact caused by heading a soccer ball.
"We hope these findings will open up new approaches for detecting, monitoring and preventing cumulative brain injuries in sport. We need to safeguard the long term health of soccer ball players at all levels, as well as individuals involved in other contact sports."
Dr Ietswaart and Dr Hunter were supported in the research by Stirling neuropsychologist Professor Lindsay Wilson and PhD student Tom Di Virgilio, consulting with leading Glasgow University Medical School Neuropathologist Dr Willie Stewart and a wider multi-disciplinary team.
In the study, scientists measured levels of brain function using a basic neuroscience technique called Transcranial Magnetic Stimulation (TMS). The findings from this study, funded by the NIHR Brain Injury Healthcare Technology Cooperative (HTC) are the first to show the TMS technique can be used to detect changes to brain function after small, routine impacts.
https://www.sciencedaily.com/releases/2016/10/161023154804.htm
This is your brain: This is your brain outdoors
Neuroscientists find differences in brain activity depending whether people are outdoors or in a lab
January 30, 2018
Science Daily/University of Alberta
The brain acts much differently when we're outdoors compared to when we're inside the lab, a new study has found.
"It happens when we're doing normal, everyday activities, like riding a bike," explained Kyle Mathewson, a neuroscientist in UAlberta's Department of Psychology.
Mathewson and his research team put EEG equipment into backpacks and had subjects perform a standard neuroscience task while riding a bike outside. The task involved identifying changes in an otherwise consistent set of stimuli, such as a higher pitch in a series of beep sounds. They had previously performed the same experiment on stationary bikes inside their lab but in the but in the new study, the scientists were able to record laboratory quality measurements of brain activity outdoors, using portable equipment.
"Something about being outdoors changes brain activity," said Joanna Scanlon, graduate student and lead author on the study. "In addition to dividing attention between the task and riding a bike, we noticed that brain activity associated with sensing and perceiving information was different when outdoors, which may indicate that the brain is compensating for environmental distractions."
The great outdoors
The study showed that our brains process stimuli, like sounds and sights, differently when we perform the same task outdoors compared to inside a lab.
"If we can understand how and what humans are paying attention to in the real world, we can learn more about how our minds work," said Scanlon. "We can use that information to make places more safe, like roadways."
"If we want to apply these findings to solve issues in our society, we need to ensure that we understand how the brain works out in the world where humans actually live, work, and play," said Mathewson, who added that almost everything we know about the human brain is learned from studies in very tightly controlled environments.
Next, the researchers will explore how this effect differs in outdoor environments with varying degrees of distraction, such as quiet path or a busy roadway.
https://www.sciencedaily.com/releases/2018/01/180130123732.htm