How Exercise Affects the Brain

Exercise clears the mind. It gets the blood pumping and more oxygen is delivered to the brain. This is familiar territory, but Dartmouth's David Bucci thinks there is much more going on. Exercise clears the mind. It gets the blood pumping and more oxygen is delivered to the brain. This is familiar territory, but Dartmouth's David Bucci thinks there is much more going on [Credit: Web] "In the last several years there have been data suggesting that neurobiological changes are happening -- [there are] very brain-specific mechanisms at work here," says Bucci, an associate professor in the Department of Psychological and Brain Sciences. From his studies, Bucci and his collaborators have revealed important new findings: The effects of exercise...

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A walk in the park gives mental boost to people with depression

A walk in the park may have psychological benefits for people suffering from depression. In one of the first studies to examine the effect of nature walks on cognition and mood in people with major depression, researchers in Canada and the U.S. have found promising evidence that a walk in the park may provide some cognitive benefits. The study was led by Marc Berman, a post-doctoral fellow at Baycrest's Rotman Research Institute in Toronto, with partners from the University of Michigan and Stanford University. It is published online this week, ahead of print publication, in the Journal of Affective Disorders. "Our study showed that participants with clinical depression demonstrated improved memory performance after a walk in nature, compared...

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Regular jogging shows dramatic increase in life expectancy

Undertaking regular jogging increases the life expectancy of men by 6.2 years and women by 5.6 years, reveals the latest data from the Copenhagen City Heart study presented at the EuroPRevent2012 meeting. Reviewing the evidence of whether jogging is healthy or hazardous, Peter Schnohr told delegates that the study's most recent analysis (unpublished) shows that between one and two-and-a-half hours of jogging per week at a "slow or average" pace delivers optimum benefits for longevity. The EuroPRevent2012 meeting, held 3 May to 5 May 2012, in Dublin, Ireland, was organised by the European Association for Cardiovascular Prevention and Rehabilitation (EACPR), a registered branch of the European Society of Cardiology (ESC). "The results of...

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Biophysics: Order in chaos

The process of skeletal muscle contraction is based around protein filaments sliding inside sarcomeres — the structural units of muscle fiber. Inside each sarcomere is a set of filament motors, which appear in different densities in different areas. Scientists previously thought that the motor force would change according to the filament load in the muscle, but recent studies have shown that the motor force actually maintains a constant level during the muscle contraction. Despite such breakthroughs, however, it remains unclear exactly how this constant force is maintained in an otherwise chaotic system. Bin Chen of the A*STAR Institute of High Performance Computing and Huajian Gao at Brown University, US, have now built a model to illustrate...

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Action Videogames Change Brains

A team led by psychology professor Ian Spence at the University of Toronto reveals that playing an action videogame, even for a relatively short time, causes differences in brain activity and improvements in visual attention. Previous studies have found differences in brain activity between action videogame players and non-players, but these could have been attributed to pre-existing differences in the brains of those predisposed to playing videogames and those who avoid them. This is the first time research has attributed these differences directly to playing video games. Twenty-five subjects -- who had not previously played videogames -- played a game for a total of 10 hours in one to two hour sessions. Sixteen of the subjects played...

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With you in the room bacteria counts spike by about 37 million bacteria per hour

A person's mere presence in a room can add 37 million bacteria to the air every hour -- material largely left behind by previous occupants and stirred up from the floor -- according to new research by Yale University engineers.  Rendering of bacteria. A person's mere presence in a room can add 37 million bacteria to the air every hour -- material largely left behind by previous occupants and stirred up from the floor -- according to new research by Yale University engineers [Credit: © Jezper/Fotolia] "We live in this microbial soup, and a big ingredient is our own microorganisms," said Jordan Peccia, associate professor of environmental engineering at Yale and the principal investigator of a study recently published online in the...

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Testosterone Makes Us Less Cooperative and More Egocentric

Testosterone makes us overvalue our own opinions at the expense of cooperation, research from the Wellcome Trust Centre for Neuroimaging at UCL (University College London) has found. The findings may have implications for how group decisions are affected by dominant individuals.  Problem solving in groups can provide benefits over individual decisions as we are able to share our information and expertise. However, there is a tension between cooperation and self-orientated behaviour: although groups might benefit from a collective intelligence, collaborating too closely can lead to an uncritical groupthink, ending in decisions that are bad for all.  Attempts to understand the biological mechanisms behind group decision making...

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How work tells muscles to grow

We take it for granted, but the fact that our muscles grow when we work them makes them rather unique. Now, researchers have identified a key ingredient needed for that bulking up to take place. A factor produced in working muscle fibers apparently tells surrounding muscle stem cell "higher ups" that it's time to multiply and join in, according to a study in the January Cell Metabolism, a Cell Press journal.  In other words, that so-called serum response factor (Srf) translates the mechanical signal of work into a chemical one.  "This signal from the muscle fiber controls stem cell behavior and participation in muscle growth," says Athanassia Sotiropoulos of Inserm in France. "It is unexpected and quite interesting." It might...

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New study puts eco-labels to the test

A new report released today by the University of Victoria ranks eco-labels intended to distinguish seafood produced with less damage to the environment. It is the first study to evaluate how eco-labels for farmed marine fish compare to unlabeled options in the marketplace. "How Green is Your Eco-label?" is designed to help seafood buyers sort through competing sustainability claims and better identify those labels that result in farming methods with less damage to the ocean. Key findings include: "Organic" labels lead the pack, although a few fall noticeably short; Many eco-labels are not much better than conventional farmed seafood options when it comes to protecting the ocean environment; Scale is a big challenge for eco-labels:...

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Vegetables, fruits, grains reduce stroke risk in women

Swedish women who ate an antioxidant-rich diet had fewer strokes regardless of whether they had a previous history of cardiovascular disease, in a study reported in Stroke: Journal of the American Heart Association.  "Eating antioxidant-rich foods may reduce your risk of stroke by inhibiting oxidative stress and inflammation," said Susanne Rautiainen, M.Sc., the study's first author and Ph.D. student at the Karolinska Institutet in Sweden. "This means people should eat more foods such as fruits and vegetables that contribute to total antioxidant capacity."  Oxidative stress is an imbalance between the production of cell-damaging free radicals and the body's ability to neutralize them. It leads to inflammation, blood vessel damage...

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"Just Chill?" Relaxing Can Make You Fatter

Conventional wisdom says that exercise is a key to weight loss — a no-brainer. But now, Tel Aviv University researchers are revealing that life as a couch potato, stretched out in front of the TV, can actually be "active inactivity" — and cause you to pack on the pounds.  Such inactivity actually encourages the body to create new fat in fat cells, says Prof. Amit Gefen of TAU's Department of Biomedical Engineering. Along with his Ph.D. student Naama Shoham, Prof. Gefen has shown that preadipocyte cells — the precursors to fat cells — turn into fat cells faster and produce even more fat when subject to prolonged periods of "mechanical stretching loads" — the kind of weight we put on our body tissues when we sit or lie down.  The...

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Dieters should eat foods rich in protein, mostly from dairy, to protect bones during weight loss

New research suggests that a calorie-restricted diet higher in protein—mostly from dairy foods—and lower in carbohydrates coupled with daily exercise has a major positive impact on bone health in overweight and obese young women.  The study, published online in the Journal of Clinical Endocrinology and Metabolism, found bone health improvements were particularly evident due to the high density of bone-supporting nutrients such as calcium, vitamin D and dairy-based protein.  For 16 weeks, three groups of overweight and obese, but otherwise healthy, premenopausal women each consumed either low, medium or high amounts of dairy foods coupled with higher or lower amounts of protein and carbohydrates. Calcium and vitamin D levels...

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The ethics of smart drugs

Professor Barbara Sahakian, Professor of Clinical Neuropsychology at the University of Cambridge, has been researching cognitive enhancers for over a decade.  Here she discusses the emergence of ‘smart drugs’ and the ethical and practical issues they raise.   There is an increasing lifestyle use of cognitive enhancing drugs, or smart drugs by healthy people. Why might this be? And how will it change our society? Are people using these drugs just realize their potential, or is it that pressures to perform in a globally competitive environment means that individuals’ feel that they cannot afford an ‘off day’ due to lack of sleep or stress?  This is perhaps particularly true of certain professions, where there are issues of...

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Exercise helps us to eat a healthy diet

A healthy diet and the right amount of exercise are key players in treating and preventing obesity but we still know little about the relationship both factors have with each other. A new study now reveals that an increase in physical activity is linked to an improvement in diet quality.  A healthy diet and the right amount of exercise are key players in treating and preventing obesity but we still know little about the relationship both factors have with each other. A new study now reveals that an increase in physical activity is linked to an improvement in diet quality [Credit: SINC] Many questions arise when trying to lose weight. Would it be better to start on a diet and then do exercise, or the other way around? And how much does...

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Physical activity impacts overall quality of sleep

People sleep significantly better and feel more alert during the day if they get at least 150 minutes of exercise a week, a new study concludes.  A nationally representative sample of more than 2,600 men and women, ages 18-85, found that 150 minutes of moderate to vigorous activity a week, which is the national guideline, provided a 65 percent improvement in sleep quality. People also said they felt less sleepy during the day, compared to those with less physical activity.  The study, out in the December issue of the journal Mental Health and Physical Activity, lends more evidence to mounting research showing the importance of exercise to a number of health factors. Among adults in the United States, about 35 to 40 percent of...

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Hefty impact of poor eating habits

Too much fast food, poor meal choices and bad eating habits are causing more Canadians to be overweight or obese. Despite this trend, individuals who eat well are 20 per cent less likely to be obese, according to a study by Concordia University economists published in the Journal of Primary Care & Community Health.  "The risk of being obese or overweight is directly related to bad eating habits such as skipping meals, eating away from home, high consumption of fast and processed foods, as well as low consumption of fruit and vegetables," says first author Sunday Azagba, a PhD candidate in the Concordia Department of Economics. "In Canada, food purchased from restaurants accounts for more than 30 per cent of the average weekly...

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Tuning out: How brains benefit from meditation

Experienced meditators seem to be able switch off areas of the brain associated with daydreaming as well as psychiatric disorders such as autism and schizophrenia, according to a new brain imaging study by Yale researchers.  Experienced meditators seem to switch off areas of the brain associated with wandering thoughts, anxiety and some psychiatric disorders such as schizophrenia. Researchers used fMRI scans to determine how the brains of meditators differed from subjects who were not meditating. The areas shaded in blue highlight areas of decreased activity in the brains of meditators [Credit: Yale University] Meditation's ability to help people stay focused on the moment has been associated with increased happiness levels, said...

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