1. How physical exercise aids in stroke recovery

    December 15, 2016 by Ashley

    From the Frontiers media release:

    The after-effects of a stroke can be life changing. Paralysis, speech problems and memory loss occur in varying degrees of severity, depending on the location and amount of brain tissue damage.

    How far a stroke patient can recover is largely determined by the ability of the brain to reorganise itself. Understanding what can improve this ability is therefore essential in developing the best therapies for rehabilitation.

    Voluntary physical exercise is known to have a positive effect on a person’s overall well-being. It delays memory loss in old age and improves cognitive ability. A new study, published in the open-access journal Frontiers in Aging Neuroscience, has linked the positive effects of exercise on the brains of mice to their better recovery after a stroke.

    Our study suggests that physical exercise can be used as a preventive, as well as a therapeutic approach to aid recovery after a cortical stroke,” says Dr. Evgenia Kalogeraki, who conducted this research at the in the laboratory of Prof. Dr. Siegrid Löwel, at Georg-August-University, Germany.

    Previous research of the Löwel laboratory has shown that mice growing up in an enriched environment, such as free access to a running wheel and increased cognitive and social stimulation, retain a more youthful brain into adulthood. In their new study, the researchers wanted to see if physical exercise alone could have these benefits, and in addition, protect and potentially rehabilitate the brain after a stroke had occurred.

    In order to do this, Kalogeraki and her co-authors used a standard test to assess the brain’s ‘plasticity’ — its ability to change the way it activates in response to an experience. When the visual input of one eye is compromised for a couple of days, then the part of the brain that processes visual information gets preferentially activated by the other, open eye. The brain’s ability to change eye dominance (called ocular dominance plasticity) is age-related, being most pronounced in juvenile animals and completely absent in older mice that have been raised without any stimulation.

    As well as confirming existing knowledge about the anti-aging effects of voluntary physical exercise — older mice that exercised retained the ability to change eye dominance in comparison to those that didn’t — the study also revealed some exciting new findings. Those mice that had free-access to a running wheel were able to maintain ocular dominance plasticity after suffering a stroke, compared to those that didn’t.

    We found that mice with free access to a running wheel throughout their life preserved a more juvenile brain into adulthood and were able to prevent the negative effects of a stroke,” reveals Kalogeraki.

    That was not all — in addition, the researchers observed that exercise could even be used therapeutically after suffering a stroke. “We also found that mice with no previous access to a running wheel showed an equally positive recovery if voluntary exercise started after a stroke had occurred,” adds Dr. Justyna Pielecka-Fortuna, co-author of the study.

    These exciting observations have the potential to provide a simple but effective method to protect and rehabilitate patients that are prone to, or have already suffered, a stroke.

    The senior author of this study, has been so inspired by this research she has taken up exercising again. “The fact that the brain can restore its youthfulness by starting physical exercise after a stroke has occurred suggests that it is never too late to benefit from exercise,” says Löwel. “I’ve started cycling again — what is good for the mice cannot be bad for me!”

    It is hoped this research will expand our knowledge of how physical exercise can have such a positive influence on the brain. “We now hope to study the mechanisms underlying exercise-mediated activity changes in the brain, to ultimately better guide studies in humans” concludes Kalogeraki.

     


  2. Moderate exercise improves memory dysfunction caused by type 2 diabetes

    December 14, 2016 by Ashley

    From the University of Tsukuba media release:

    diabetes blood sugarUniversity of Tsukuba-led researchers show that moderate exercise may improve hippocampal memory dysfunction caused by type 2 diabetes and that enhanced transport of lactate to neurons may be the underlying mechanism

    Type 2 diabetes is characterized by impaired glucose metabolism and can cause central nervous system-related complications, such as memory dysfunction. The hippocampus is an essential brain component for normal memory formation. However, the effect of impaired glycometabolism on hippocampal-mediated memory in type 2 diabetes patients is not known.

    In a new study, researchers centered at the University of Tsukaba investigated whether hippocampal glucose metabolism and memory function is altered in a rat model of type 2 diabetes. Based on the idea that exercise normalizes glycometabolism and improves memory function, the research team also investigated the effects of exercise on hippocampal glycometabolism and memory formation.

    Hippocampal function was evaluated by placing the rat in a circular pool and testing its ability to remember the location of a platform that would allow it to escape from the water. “This is a well-established method for measuring spatial learning and memory,” study first author Takeru Shima says.

    Type 2 diabetic rats needed more time to escape the water and find the platform. However, after 4 weeks of moderate exercise, they were able to find the platform much faster. “This indicated that exercise significantly improved spatial memory impairments in type 2 diabetic rats,” Shima explains.

    Glycogen levels are altered in tissues of diabetes patients, leading to a variety of complications. However, glycogen levels have not yet been investigated in the hippocampus. “We showed for the first time that glycogen levels are significantly higher in the hippocampus of diabetic rats,” corresponding author Hideaki Soya says.

    Interestingly, single bout of exercise reduced hippocampal glycogen levels and this correlated with an increase in lactate levels. Lactate is an energy substrate and neuromodulator in the hippocampus, and is known to enhance memory formation. Lactate is transferred to neurons through monocarboxylate transporters (MCTs). “MCT2 expression was significantly lower in the hippocampus of type 2 diabetic rats,” Soya says, “dysregulated MCT2-mediated neuronal uptake of lactate is a possible aetiology of memory dysfunction in type 2 diabetes, and that elevated hippocampal glycogen may be an adaptive change to compensate for the decreased lactate utilization.”

    4 weeks of moderate exercise further enhanced glycogen levels and normalized MCT2 expression in the hippocampus of type 2 diabetic rats.” These findings suggest that disrupted MCT2-mediated uptake of lactate by neurons contributes to memory dysfunction in type 2 diabetic rats.

    The findings indicate that moderate exercise could be used to treat memory impairment in patients with type 2 diabetes by promoting the transfer of glycogen-derived lactate to hippocampal neurons.


  3. Want to exercise more? Get yourself some competition

    November 9, 2016 by Ashley

    From the University of Pennsylvania media release:

    battle_sexesImagine you’re a CEO trying to get your employees to mg{exercise}. Most health incentive programs have an array of tools — pamphlets, websites, pedometers, coaching, team activities, step challenges, money — but what actually motivates people? Is it social support? Competition? Teamwork? Corporate leaders often try a little bit of everything.

    A new study published in the journal Preventative Medicine Reports from the Annenberg School for Communication at the University of Pennsylvania found these efforts should hone in on one area: Competition. It was a far stronger motivation for exercise than friendly support, and in fact, giving people such support actually made them less likely to go to the gym less than simply leaving them alone.

    “Most people think that when it comes to social media more is better,” says Damon Centola, an associate professor in Penn’s Annenberg School and the School of Engineering and Applied Sciences, and senior author on the paper. “This study shows that isn’t true: When social media is used the wrong way, adding social support to an online health program can backfire and make people less likely to choose healthy behaviors. However, when done right, we found that social media can increase people’s fitness dramatically.”

    For this research, Centola and Jingwen Zhang, Ph.D., lead paper author and recent Annenberg graduate, recruited nearly 800 Penn graduate and professional students to sign up for an 11-week exercise program called “PennShape.” The federally funded, university-wide fitness initiative created by Centola and Zhang provided Penn students with weekly exercise classes in the University fitness center, fitness mentoring, and nutrition advice, all managed through a website the researchers built. After program completion, the students who attended the most exercise classes for activities like running, spinning, yoga, and weight lifting, among others, won prizes.

    What the participants didn’t know was that the researchers had split them into four groups to test how different kinds of social networks affected their exercise levels. The four groups were: individual competition, team support, team competition, and a control group.

    In the individual group, participants could see exercise leaderboards listing anonymous program members, and earned prizes based on their own success attending classes. For each team group, participants were assigned to a unit. In the team support group, they could chat online and encourage team members to exercise, with rewards going to the most successful teams with the most class attendance. In addition, those in the team competition group could see a leaderboard of other teams and their team standing. Participants in the control group could use the website and go to any class, but were not given any social connections on the website; prizes in this group were based on individual success taking classes.

    Overwhelmingly, competition motivated participants to exercise the most, with attendance rates 90% higher in the competitive groups than in the control group. Both team and individual competition equally drove the students to work out, with participants in the former taking a mean of 38.5 classes a week and those in the latter taking 35.7. Members of the control group went to the gym far less often, on average 20.3 times a week.

    The biggest surprise came in the number of workouts a week by members of the team support group: Just 16.8, on average — half the exercise rate of the competitive groups.

    “Framing the social interaction as a competition can create positive social norms for exercising,” Zhang says, now an assistant professor at the University of California, Davis. “Social support can make people more dependent on receiving messages, which can change the focus of the program.”

    How organizations use social media can affect how receptive people are to online signals, explains Centola, an expert on social networks and diffusion.

    Supportive groups can backfire because they draw attention to members who are less active, which can create a downward spiral of participation,” Centola says. In the competitive groups, however, people who exercise the most give off the loudest signal. “Competitive groups frame relationships in terms of goal-setting by the most active members. These relationships help to motivate exercise because they give people higher expectations for their own levels of performance.”

    Competition triggers a social ratcheting-up process, he adds. “In a competitive setting, each person’s activity raises the bar for everyone else. Social support is the opposite: a ratcheting-down can happen. If people stop exercising, it gives permission for others to stop, too, and the whole thing can unravel fairly quickly.”

    The positive effects of social competition go beyond exercise, to encouraging healthy behaviors such as medication compliance, diabetes control, smoking cessation, flu vaccinations, weight loss, and preventative screening, as well as pro-social behaviors like voting, recycling, and lowering power consumption.

    “Social media is a powerful tool because it can give people new kinds of social influences right in their own home,” Centola says. “Lifestyle changes are hard to make, but if you can give people the right kinds of social tools to help them do it, there’s a lot of good that can be done at relatively little cost.


  4. Stimulating the brain makes exercising the legs feel easier

    November 4, 2016 by Ashley

    From the University of Kent media release:

    battle_sexesResearch led by the University of Kent shows stimulation of the brain impacts on endurance exercise performance by decreasing perception of effort.

    The study examined the effect of a technique called transcranial direct-current stimulation (tDCS), a form of non-invasive brain stimulation, on the neuromuscular, physiological and perceptual responses to exhaustive leg exercise.

    Researchers led by Dr Lex Mauger from Kent’s School of Sport and Exercise Sciences found that tDCS delayed exhaustion of the leg muscles by an average of 15% during an exercise task, and that this was likely caused by the participants feeling less effort during the exercise. However, tDCS elicited no significant effect on the neuromuscular response to exercise.

    The performance effects of tDCS only occurred when the tDCS electrodes used to deliver the electrical current were positioned in a particular way. This study therefore provides important methodological guidance for the application of tDCS and provides further evidence that brain stimulation can improve endurance exercise performance, although the authors warn against the uncontrolled use of tDCS.

    ‘Transcranial direct current stimulation improves isometric time to exhaustion of the knee extensors’ (A. R. Mauger, L. Agnius, J. Hopker, S. M.Marcora, all University of Kent and B.Pageaux, Universite de Bourgogne) is published in the journal Neuroscience.

     


  5. Discrimination Based on Weight Doubles Health Risks

    October 21, 2016 by Ashley

    From the University of Rhode Island media release:

    obesityWe all know that carrying extra pounds can be bad for your health. Now a URI professor has found that how society treats overweight people makes matters worse.

    Maya Vadiveloo, assistant professor of nutrition and food sciences in the College of Health Sciences, and Josiemer Mattei, assistant professor of nutrition at Harvard University T.H. Chan School of Public Health, analyzed weight discrimination data from the long-term national study, Midlife Development in the United States.

    The researchers focused on respondents who reported regularly experiencing discrimination because of their weight. The study asked whether they were treated discourteously, called names, or made to feel inferior. Those who experienced weight discrimination over a 10-year period had twice the risk of high allostatic load, the cumulative dysfunction of bodily systems from chronic stress, they found. That stress can lead to heart disease, diabetes, inflammation and other disorders, increasing risk of death.

    “It is a pretty big effect,” Vadiveloo, of North Kingstown, says of the findings. “Even if we accounted for health effects attributed to being overweight, these people still experience double the risk of allostatic load because of weight discrimination.”

    The findings, published in the August issue of Annals of Behavioral Medicine, expose flaws in society’s approach to weight control, Vadiveloo says. “The main message is to be aware that the way we treat people may have more negative effects than we realize,” she says. “Our paper highlights the importance of including sensitivity and understanding when working with individuals with obesity and when developing public health campaigns.”

    People who experience weight discrimination often shun social interaction and skip doctor visits, she notes. “There is so much shaming around food and weight. We need to work together as a nation on improving public health and clinical support for individuals with obesity and targeting environmental risk factors,” she says. For example, Vadiveloo suggests developing strategies to make healthy foods affordable and creating safe places for people to be active.

    Vadiveloo hopes to address the topic in the classroom and revisit data from the nearly 1,000 respondents to explore whether having more social support or positive coping strategies reduces negative health effects of weight discrimination.


  6. Older adults gain weight when spouse is stressed out

    October 20, 2016 by Ashley

    From the University of Michigan media release:

    marriageStress isn’t good for your waist line. For older married couples, the added pounds may be caused by a spouse’s long-term stress levels.

    A new University of Michigan study looked at how the negative quality of marriage can be detrimental for weight gain — possibly leading to obesity — when couples 50 and older are stressed. The results varied by gender.

    The study specifically focused on chronic stress, which is an ongoing circumstance occurring for more than a year and threatens to overwhelm an individual’s resources, such as financial problems, difficulties at work or long-term caregiving.

    Participants came from the nationally longitudinal Health and Retirement Study at the U-M Institute for Social Research. The sample included 2,042 married individuals who completed questions about their waist circumference, negative marriage quality, stress levels and other factors in 2006 and 2010. Couples were married for an average of 34 years.

    Greater negative quality ties as reported by husbands exacerbated the effects of partner stress on both husbands’ and wives’ waist circumference.

    Interestingly, lower negative quality ties reported by wives exacerbated the effect of wife stress on husbands’ waist circumference, said Kira Birditt, a research associate professor at ISR’s Survey Research Center.

    For the increased risk of obesity, 59 percent of the husbands and 64 percent of the wives were at higher risk of disease in the study’s first assessment, whereas 66 percent of husbands and 70 percent of wives were at increased risk at the study’s conclusion.

    About 9 percent of the participants showed a 10 percent increase in waist circumference, which represented an average increase of four inches of more over four years, the study indicated.

    “Marriage has powerful influences on health,” said Birditt, the study’s lead author. “The stress experienced by partners, and not the individual’s stress, was associated with increased waist circumference. This effect of stress was even stronger in particular spousal relationships.”

    Husbands, she said, usually experience lower negative marital quality and thus greater negative feelings may be less expected and more harmful. Because women tend to report greater negative marital quality, low levels of negative marital quality among wives may be an indicator of a lack of investment in the marriage.

    Researchers said the study does not address what to do to lessen stress. However, other findings indicate that it’s important for couples to cope with stress together, and that goals created by a couple can be more effective than goals created individually.

    Birditt said the findings are applicable to younger couples. Previous research has shown that stress has strong effects on marital quality among this group, too.

    “We can only assume that this may translate into health effects, although they are probably not as strong on younger, often healthier, samples,” she said.

    The study’s other authors were Nicky Newton, assistant professor at Wilfrid Laurier University in Canada, and U-M researchers Jim Cranford and Noah Webster.

    The findings appear in the Journals of Gerontology: Social Sciences.

     


  7. Stress and obesity biologically linked

    October 11, 2016 by Ashley

    From the Hebrew University of Jerusalem media release:

    obesityMetabolic and anxiety-related disorders both pose a significant healthcare burden, and are in the spotlight of contemporary research and therapeutic efforts. Although intuitively we assume that these two phenomena overlap, the link has not been proven scientifically.

    Now, a team of researchers from the Hebrew University of Jerusalem, headed by Prof. Hermona Soreq from the Edmond and Lily Safra Center for Brain Sciences and the Department of Biological Chemistry at the Faculty of Mathematics and Sciences, revealed the molecular elements that bridge anxiety and metabolism — a type of microRNA that influences shared biological mechanisms.

    “We already know that there is a connection between body and mind, between the physical and the emotional, and studies show that psychological trauma affects the activity of many genes. Our previous research found a link between microRNA and stressful situations — stress and anxiety generate an inflammatory response and dramatically increase the expression levels of microRNA regulators of inflammation in both the brain and the gut, for example the situation of patients with Crohn’s disease may get worse under psychological stress, “says Prof. Soreq.

    “In the present study, we added obesity to the equation. We revealed that some anxiety-induced microRNA are not only capable of suppressing inflammation but can also potentiate metabolic syndrome-related processes. We also found that their expression level is different in diverse tissues and cells, depending on heredity and exposure to stressful situations,” explains Prof. Soreq.

    The family of microRNA genes is part of the human genome, which was considered until not too long ago as “junk-DNA.” However, microRNAs are now known to fulfill an important role in regulating the production process of proteins by other genes. These tiny RNA molecules, which are one percent of the average size of a protein-coding gene, act as suppressors of inflammation and are able to halt the production of proteins.

    The research paper, published in the journal Trends in Molecular Medicine, details the evidence linking microRNA pathways, which share regulatory networks in metabolic and anxiety-related conditions. In particular, microRNAs involved in these disorders include regulators of acetylcholine signaling in the nervous system and their accompanying molecular machinery.

    Metabolic disorders, such as abdominal obesity and diabetes, have become a global epidemic. In the USA, the prevalence of metabolic syndrome is as high as 35 percent. In other countries, such as Austria, Denmark and Ireland it affects 20-25 percent of the population.

    Anxiety disorders are harder to quantify than metabolic ones. They include obsessive-compulsive disorder (OCD), post-traumatic stress disorder (PTSD) and phobia. The full burden of the anxiety spectrum is difficult to assess, due to under-diagnosis and poorly defined pathophysiological processes.

    This newly revealed link offers novel opportunities for innovative diagnoses and treatment of both metabolic and anxiety-related phenomena.

    “The discovery has a diagnostic value and practical implications, because the activity of microRNAs can be manipulated by DNA-based drugs,” explains Prof. Soreq. “It also offers an opportunity to reclassify ‘healthy’ and ‘unhealthy’ anxiety and metabolic-prone states, and inform putative strategies to treat these disorders.”

     


  8. Brain benefits of aerobic exercise lost to mercury exposure

    September 21, 2016 by Ashley

    From the NIH/National Institute of Environmental Health Sciences media release:

    pregnancy husbandCognitive function improves with aerobic exercise, but not for people exposed to high levels of mercury before birth, according to research funded by the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health. Adults with high prenatal exposure to methylmercury, which mainly comes from maternal consumption of fish with high mercury levels, did not experience the faster cognitive processing and better short term memory benefits of exercise that were seen in those with low prenatal methylmercury exposures.

    This is one of the first studies to examine how methylmercury exposure in the womb may affect cognitive function in adults. Mercury comes from industrial pollution in the air that falls into the water, where it turns into methylmercury and accumulates in fish. The scientists, based at the Harvard T.H. Chan School of Public Health, suspect that prenatal exposure to methylmercury, known to have toxic effects on the developing brain and nervous system, may limit the ability of nervous system tissues to grow and develop in response to increased aerobic fitness.

    “We know that neurodevelopment is a delicate process that is especially sensitive to methylmercury and other environmental toxins, but we are still discovering the lifelong ripple effects of these exposures,” said Gwen Collman, Ph.D., director of the NIEHS Division of Extramural Research and Training. “This research points to adult cognitive function as a new area of concern..”

    The 197 study participants are from the Faroe Islands, 200 miles north of England, where fish is a major component of the diet. Their health has been followed since they were in the womb in the late 1980s. At age 22, this subset of the original 1,022 participants took part in a follow-up exam that included estimating the participants’ VO2 max, or the rate at which they can use oxygen, which increases with aerobic fitness. Also, a range of cognitive tests were performed related to short-term memory, verbal comprehension and knowledge, psychomotor speed, visual processing, long-term storage and retrieval, and cognitive processing speed.

    Overall, the researchers found that higher VO2 max values were associated with better neurocognitive function, as expected based on prior research. Cognitive efficiency, which included cognitive processing speed and short term memory, benefitted the most from increased VO2 max.

    But when the researchers divided the participants into two groups based on the methylmercury levels in their mothers while they were pregnant, they found that these benefits were confined to the group with the lowest exposure. Participants with prenatal methylmercury levels in the bottom 67 percent, or levels of less than 35 micrograms per liter in umbilical cord blood, still demonstrated better cognitive efficiency with higher VO2 max. However, for participants with higher methylmercury levels, cognitive function did not improve as VO2 max increased.

    “We know that aerobic exercise is an important part of a healthy lifestyle, but these findings suggest that early-life exposure to pollutants may reduce the potential benefits,” added Collman. “We need to pay special attention to the environment we create for pregnant moms and babies.”

    The U.S. Food and Drug Administration recommends that children and women of childbearing age eat two to three weekly servings of fish low in mercury as part of a healthy diet. Low mercury fish include salmon, shrimp, pollock, canned light tuna, tilapia, catfish, and cod. Four types of fish should be avoided because of typically high mercury levels — tilefish from the Gulf of Mexico, shark, swordfish, and king mackerel.

    The findings were published Sept. 9 in the journal Environmental Health Perspectives. In addition to NIH funding, the research was supported by the Danish Council for Strategic Research, Programme Commission on Health, Food, and Welfare.

     


  9. Believe it or not: Exercise does more good if you believe it will

    August 15, 2016 by Ashley

    From the Albert-Ludwigs-Universität Freiburg media release:

    battle_sexesEveryone knows exercise is supposed to be good for your health, but is the belief that exercise will have a positive effect more important for our well-being than the exercise itself?

    The psychologist Hendrik Mothes from the University of Freiburg’s Department of Sport Science and his team have conducted a study demonstrating that test subjects derive more psychological as well as neurophysiological benefits from exercise if they already have positive mindsets about sports. Moreover, the team provided evidence that test subjects can be positively or negatively influenced in this regard before engaging in the exercise. The study was published in the Journal of Behavioral Medicine.

    The researchers invited 76 men and women aged between 18 and 32 years to their research laboratory, where they had to exercise for 30 minutes on a bicycle ergometer. Beforehand, the test subjects were separated into different groups and shown one of several short films that either praised the positive effects of cycling on health or not. In addition, the researchers asked the test subjects whether they had already believed in the positive effects of physical activity before beginning the study. The participants filled out questionnaires asking them about their well-being and their mood before and after the exercise. Moreover, the researchers measured the participants’ brain activity with an electroencephalogram (EEG).

    The results demonstrate that our belief in how much we will benefit from physical activity has a considerable effect on our well-being in the manner of a self-fulfilling prophecy,” sums up Mothes. The results provide evidence for a placebo effect during exercise: Test subjects who already believed the physical activity would have positive effects before participating in the study enjoyed the exercise more, improved their mood more, and reduced their anxiety more than less optimistic test subjects. In addition, the study revealed a neurophysiological difference between the test subjects: According to the measurements of brain activity, the participants with greater expectations before the beginning of the study and those who had seen a film about the health benefits of cycling beforehand were more relaxed on a neuronal level.

    The results likely also apply to other endurance sports like jogging, swimming, or cross-country skiing, reports Mothes. “Beliefs and expectations could possibly have long-term consequences, for instance on our motivation to engage in sports. They can be a determining factor on whether we can rouse ourselves to go jogging again next time or decide instead to stay at home on the couch.” The psychologist is now working on his next project. He aims to study further effects of mindsets and investigate the question of whether and how they influence the experience of exertion during physical activity.

     


  10. Need to remember something? Exercise four hours later!

    June 22, 2016 by Ashley

    From the Cell Press media release:

    studying hardA new study suggests an intriguing strategy to boost memory for what you’ve just learned: hit the gym four hours later.

    The findings reported in the Cell Press journal Current Biology on June 16 show that physical exercise after learning improves memory and memory traces, but only if the exercise is done in a specific time window and not immediately after learning.

    “It shows that we can improve memory consolidation by doing sports after learning,” says Guillén Fernández of the Donders Institute at the Radboud University Medical Center in the Netherlands.

    In the new study, Fernández, along with Eelco van Dongen and their colleagues, tested the effects of a single session of physical exercise after learning on memory consolidation and long-term memory. Seventy-two study participants learned 90 picture-location associations over a period of approximately 40 minutes before being randomly assigned to one of three groups: one group performed exercise immediately, the second performed exercise four hours later, and the third did not perform any exercise. The exercise consisted of 35 minutes of interval training on an exercise bike at an intensity of up to 80 percent of participants’ maximum heart rates. Forty-eight hours later, participants returned for a test to show how much they remembered while their brains were imaged via magnetic resonance imaging (MRI).

    The researchers found that those who exercised four hours after their learning session retained the information better two days later than those who exercised either immediately or not at all. The brain images also showed that exercise after a time delay was associated with more precise representations in the hippocampus, an area important to learning and memory, when an individual answered a question correctly.

    “Our results suggest that appropriately timed physical exercise can improve long-term memory and highlight the potential of exercise as an intervention in educational and clinical settings,” the researchers conclude.

    It’s not yet clear exactly how or why delayed exercise has this effect on memory. However, earlier studies of laboratory animals suggest that naturally occurring chemical compounds in the body known as catecholamines, including dopamine and norepinephrine, can improve memory consolidation, the researchers say. One way to boost catecholamines is through physical exercise.

    Fernández says they will now use a similar experimental setup to study the timing and molecular underpinnings of exercise and its influence on learning and memory in more detail.