The fast and the curious: Fitter adults have fitter brains
Large database links fitness to better cognitive performance and healthy white matter in brain
September 9, 2019
Science Daily/European College of Neuropsychopharmacology
In a large study, German scientists have shown that physical fitness is associated with better brain structure and brain functioning in young adults. This opens the possibility that increasing fitness levels may lead to improved cognitive ability, such as memory and problem solving, as well as improved structural changes in the brain. This work is presented for the first time at the ECNP Congress in Copenhagen, with simultaneous publication in the peer-reviewed journal Scientific Reports.
Scientists have previously shown that "exercise is good for the brain," but most studies have not controlled for underlying causes which might give distorted results, such as body weight, blood glucose levels, education status, age and other factors, making it difficult to take an overall view of the benefits. In addition, studies have rarely looked at fitness in relations to both brain structure and mental functioning.
The scientists used a publicly available database of 1206 MRI brain scans from the Human Connectome Project, which had been contributed by volunteers who wanted to contribute to scientific research. The volunteers (average age 30 years old) underwent some additional testing. The first test was a "two-minute walking test," where each person was asked to walk as fast as possible for 2 minutes and the distance was then measured. The volunteers then underwent a series of cognitive tests, to measure such things as memory, sharpness, judgement, and reasoning.
As team leader, Dr Jonathan Repple (University Hospital Muenster, Germany) said "The great strength of this work is the size of the database. Normally when you are dealing with MRI work, a sample of 30 is pretty good, but the existence of this large MRI database allowed us to eliminate possibly misleading factors, and strengthened the analysis considerably."
The tests were able to show two main points: better performance on a 2-minute walking test in young healthy adults is associated with better cognitive performance, and with structural integrity of the white matter in the brain: healthy white matter is known to improve the speed and quality of nerve connections in the brain.
Repple continued, "It surprised us to see that even in a young population cognitive performance decreases as fitness levels drops. We knew how this might be important in an elderly population which does not necessarily have good health, but to see this happening in 30 year olds is surprising. This leads us to believe that a basic level of fitness seems to be a preventable risk factor for brain health.
This type of study raises an important question. We see that fitter people have better brain health, so we now need to ask whether actually making people fitter will improve their brain health. Finding this out is our next step. There are some trials which point in that direction, but if we can prove this using such a large database, this would be very significant."
Commenting, Professor Peter Falkai (University Clinic, Munich, Germany) said:
"This is an important cross-sectional study demonstrating a robust correlation between physical health and cognitive functioning in a large cohort of healthy young adults. This correlation was backed by changes in the white matter status of the brain supporting the notion that better macro-connectivity is related to better brain functioning. It stresses the importance of physical activity at all stages of life and as preliminary recent evidence suggests one can start improving physical health even in later life even if one has never trained before (see reference). These findings however need to be replicated in longitudinal studies and translated for the use in mental illness."
https://www.sciencedaily.com/releases/2019/09/190909121245.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
Lower IQ and poorer fitness in teen years increase risk of early-onset dementia
March 10, 2014
Science Daily/University of Gothenburg
Men who at the age of 18 years have poorer cardiovascular fitness and/or a lower IQ more often suffer from dementia before the age of 60. This is shown in a recent study encompassing more than one million Swedish men.
In several extensive studies, researchers at the Sahlgrenska Academy of Gothenburg University have previously analyzed Swedish men's conscription results and were able to show a correlation between cardiovascular fitness as a teenager and health problems in later life.
Increased risk for early-onset dementia
In their latest study, based on data from 1.1 million young Swedish men, the Gothenburg researcher team shows that those with poorer cardiovascular fitness and/or lower IQ in their teenage years more often suffer from early-onset dementia.
"Previous studies have shown the correlation between cardiovascular fitness and the risk of dementia in old age. Now, for the first time, we can show that the increased risk also applies to early-onset dementia and its precursors," says Sahlgrenska Academy researcher Jenny Nyberg, who headed the study.
Controlled for other risk factors
Expressed in figures, the study shows that men who when conscripted had poorer cardiovascular fitness were 2.5 times more likely to develop early-onset dementia later in life. A lower IQ entailed a 4 times greater risk, and a combination of both poor cardiovascular fitness and low IQ entailed a 7 times greater risk of early-onset dementia.
The increased risk remained even when controlled for other risk factors, such as heredity, medical history, and social-economic circumstances.
Fitness strengthens the brain
"We already knew that physical and cognitive exercise reduces the risk of neurological disease. Physical exercise increases nerve cell complexity and function and even generation of new nerve cells in the adult brain, which strengthens our mental and physiological functions. In other words, good cardiovascular fitness makes the brain more resistant to damage and disease," says Prof. Georg Kuhn, senior author of the study.
Overlooked group
People who develop early-onset dementia are often of working age and can have children still living at home, which means the consequences for both the sufferers and their families are even more serious. Despite this, patients with early-onset dementia are a relatively overlooked group.
"This makes it important to initiate more research into how physical and mental exercise can affect the prevalence of different types of dementia. Perhaps exercise can be used as both a prophylactic and a treatment for those in the risk zone for early-onset dementia," says Nyberg.
http://www.sciencedaily.com/releases/2014/03/140310102208.htm