Active body, active mind: The secret to a younger brain may lie in exercising your body

 

Stroop-interference-related cortical activation patterns. Credit: Image courtesy of University of Tsukuba It is widely recognised that our physical fitness is reflected in our mental fitness, especially as we get older. How does being physically fit affect our aging brains? Neuroimaging studies, in which the activity of different parts of the brain can be visualised, have provided some clues. Until now, however, no study has directly linked brain activation with both mental and physical performance. As reported in the latest volume of the journal NeuroImage, an exciting new study led by Dr Hideaki Soya from the University of Tsukuba in Japan and his colleagues show, for the first time, the direct relationship between brain activity, brain function and physical fitness in a group of older Japanese men. They found that the fitter men performed better mentally than the less fit men, by using parts of their brains in the same way as in their youth. As we age, we use different parts of our brain compared to our younger selves. For example, when young, we mainly use the left side of our prefrontal cortex (PFC) for mental tasks involving short term memory, understanding the meaning of words and the ability to recognize previously encountered events, objects, or people. When older, we tend to use the equivalent parts of our PFC on the right side of the brain for these tasks. The PFC is located in the very front of the brain, just behind the forehead. It has roles in executive function, memory, intelligence, language and vision. With tasks involving the temporary storage and manipulation of memory, long term memories and inhibitory control, young adults favor the right side of the PFC, while older adults engage both the right and left PFC. In fact, with aging, we tend to use both sides of the PFC during mental tasks, rather than just one. This phenomenon has been coined HAROLD (hemispheric asymmetry reduction in older adults) and reflects the reorganisation of the brain as compensation for reduced brain capacity and efficiency due to age-related structural and physiological decline. In the NeuroImage study, 60 older men (aged 64-75 years) underwent an exercise test to measure their aerobic fitness. The men, whose physical fitness was found to vary widely, then performed a test to measure their selective attention, executive function and reaction time. This well-known 'color-word matching Stroop test' involved showing the men words meaning color, such as blue, green, red, but asking them to name the color of the letters rather than read the word itself. This is harder than it sounds. When the color of the letters does not match the word -- blue, red, green -- it takes the brain longer to react. This reaction time is used as a measurement of brain function. Activity in the PFC region of the mens' brains was measured throughout the test using a unique neuroimaging technique called functional near infrared spectroscopy or fNIRS. This technique provides a measure of blood oxygen concentration in surface blood vessels, indicative of activity in the brain's outer layers, using a set of wearable probes in a cap that is placed on the head. Active brain cells require fresh oxygenated blood which dislodges the deoxygenated blood from that region. fNIRS measures the changes in color between oxygenated red blood and blue deoxygenated blood and thus indirectly measures brain activity. The results from these tests were combined and extensively statistically analysed to explore the associations between aerobic fitness, Stroop reaction time and brain activity during the Stroop test. As predicted for older adults, during the Stroop test both sides of the PFC are active, with no difference between right and left, verifying the HAROLD phenomenon amongst this group of men. Previous studies have shown that young adults favour the left side of the PFC for this task. Analysis of the relationship between brain activity and Stroop reaction time revealed that those men that favored the left side of the PFC while performing the Stroop test had faster reaction times. This indicates that older adults who use the more youth-like, task-related side of the brain perform better in this test. Next, the association between aerobic fitness and Stroop reaction time was analysed. Fitter men had shorter reaction times. Based on these findings, the researchers correctly predicted that higher aerobic fitness would be associated with higher left-PFC activity. In other words, fitter men tend to use the more youth-like side of their brains, at least while performing the Stroop test. Previous studies have not examined the interaction between the three factors under investigation in this study -- aerobic fitness, mental performance and brain activation. Using clever statistical tests called mediation analyses to look at these interactions, the researchers found that aerobically fitter older men can perform better mentally than less fit older men by using the more important brain regions when needed. In fact, the fitter older men are using parts of their brains in the same way as when they were younger. How do they do this? Professor Soya says "one possible explanation suggested by the research is that the volume and integrity of the white matter in the part of brain that links the two sides declines with age. There is some evidence to support the theory that fitter adults are able to better maintain this white matter than less fit adults, but further study is needed to confirm this theory." If you are an aging woman, you will be wondering if these results can be applied to your female brain. Both aging sexes might also wonder whether increasing aerobic fitness later in life can increase mental fitness. The results aren't in, but I'm heading off for a brisk walk just in case.   http://www.sciencedaily.com/releases/2015/10/151023084456.htm

Depression and anxiety: Exercise eases symptoms

 

Depression symptoms often improve with exercise. Here are some realistic tips to help you get started and stay motivated By Mayo Clinic Staff When you have anxiety or depression, exercise often seems like the last thing you want to do. But once you get motivated, exercise can make a big difference. Exercise helps prevent and improve a number of health problems, including high blood pressure, diabetes and arthritis. Research on anxiety, depression and exercise shows that the psychological and physical benefits of exercise can also help reduce anxiety and improve mood. The links between anxiety, depression and exercise aren't entirely clear — but working out and other forms of physical activity can definitely ease symptoms of anxiety or depression and make you feel better. Exercise may also help keep anxiety and depression from coming back once you're feeling better. How does exercise help depression and anxiety? Regular exercise probably helps ease depression in a number of ways, which may include: Releasing feel-good brain chemicals that may ease depression (neurotransmitters, endorphins and endocannabinoids) Reducing immune system chemicals that can worsen depression Increasing body temperature, which may have calming effects Regular exercise has many psychological and emotional benefits, too. It can help you: Gain confidence. Meeting exercise goals or challenges, even small ones, can boost your self-confidence. Getting in shape can also make you feel better about your appearance. Take your mind off worries. Exercise is a distraction that can get you away from the cycle of negative thoughts that feed anxiety and depression. Get more social interaction. Exercise and physical activity may give you the chance to meet or socialize with others. Just exchanging a friendly smile or greeting as you walk around your neighborhood can help your mood. Cope in a healthy way. Doing something positive to manage anxiety or depression is a healthy coping strategy. Trying to feel better by drinking alcohol, dwelling on how badly you feel, or hoping anxiety or depression will go away on its own can lead to worsening symptoms. Is a structured exercise program the only option? Some research shows that physical activity such as regular walking — not just formal exercise programs — may help improve mood. Physical activity and exercise are not the same thing, but both are beneficial to your health. Physical activity is any activity that contracts muscles and expends energy and can include work or household or leisure activities. Exercise is a planned, structured and repetitive body movement done to improve or maintain physical fitness. The word "exercise" may make you think of running laps around the gym. But exercise includes a wide range of activities that boost your activity level to help you feel better. Certainly running, lifting weights, playing basketball and other fitness activities that get your heart pumping can help. But so can physical activity such as gardening, washing your car, walking around the block or engaging in other less intense activities. Any physical activity that gets you off the couch and moving can help improve your mood. You don't have to do all your exercise or other physical activity at once. Broaden how you think of exercise and find ways to add small amounts of physical activity throughout your day. For example, take the stairs instead of the elevator. Park a little farther away from work to fit in a short walk. Or, if you live close to your job, consider biking to work. Next   http://www.mayoclinic.org/diseases-conditions/depression/in-depth/depression-and-exercise/art-20046495

"Compound 14" mimics the effects of exercise without setting foot in the gym

 

A newly developed molecule has been found to mimic the effects of exercise, including weight loss and improved glucose tolerance in mice (Credit: Shutterstock) Enjoying the health benefits of a back-breaking workout without actually working out sure is a tantalizing prospect. This goes a long way to explaining the torrent of exercise equipment that promises to do more for our figures with less of our sweat and tears, and recently, the development of drugs that could imitate the beneficial effects of exercise. The latest advance in this area is the development of a molecule that mimics the effects of exercise by influencing the metabolic process, giving it the potential to treat type 2 diabetes and obesity. The scientists at the University of Southampton who developed the molecule initially set out to target the central energy sensor in cells called AMPK. Pointing to previous research, the team believed that if a small molecule could be used to selectively activate AMPK, it could boost the uptake of glucose and oxygen in the cells by mimicking the effects of exercise. The small molecule, dubbed "compound 14", works by inhibiting the function of a cellular enzyme involved in metabolism called ATIC. This causes an accumulation of another molecule in the cells called ZMP, which tricks the cells into acting as if they are running out of energy, kicking AMPK into action to trigger the cells to increase glucose uptake and metabolism. Compound 14 was given to two sets of mice, with one group fed a regular diet and the other fed high-fat foods so as to make them obese and intolerant to glucose, a symptom of pre-diabetes. The weight of the healthy mice remained the same after treatment with compound 14, as did their blood glucose levels. Meanwhile, the heightened blood glucose levels in the obese mice was reduced to near-normal levels after just a single dose of compound 14. Taking things a step further, the team treated the obese mice with compound 14 for seven days and found that it improved their glucose tolerance and also shaved 1.5 g (0.05 oz), or around five percent, off their body weight. Subjecting the healthy mice to the same treatment brought about no changes in weight. Compound 14 joins a host of other potential drugs that could be used to tackle bad health. In 2013, a drug under development at The Scripps Institute was found to increase the metabolic activity in skeletal muscles of mice, improving their muscle mass and fitness. We've also seen exercise-mimicking drugs that promise to better transform white fat into brown and ones that promise to reverse age-dependent diabetes. The University of Southampton researchers will now continue to develop compound 14 and study the effects of long-term treatment. If it proves safe, the researchers say a drug could be developed aimed at those suffering diabetes and obesity. The research was published in the journal Chemistry and Biology. Source: University of Southampton

It's Not What You Do, but How You Get Yourself to Exercise That Matters, study finds

 

Alison Phillips' study is the first to explore the importance of different habit components in predicting exercise frequency. Credit: Christopher Gannon, Iowa State University Developing any habit -- good or bad -- starts with a routine, and exercise is no exception. The trick is making exercise a habit that is hard to break. According to a new Iowa State University study, that may be easier to accomplish by focusing on cues that make going for a run or to the gym automatic. Some interventions designed to help people start and continue exercising may focus on the execution habit, or an exact routine to follow at the gym, said Alison Phillips, an assistant professor of psychology at Iowa State. However, Phillips' research, published in the journal Health Psychology, found that it's the instigation habit -- or cues that prompt people to automatically go to the gym -- that increases exercise frequency. "From a health perspective, we want people to engage in physical activity frequently, and so instigation habit is the type of habit to promote that to happen," Phillips said. "Regardless of the type of exercise you're going to do on a particular day, if you have an instigation habit, you'll start exercising without having to think a lot about it or consider the pros and cons." For example, Phillips says many people exercise after work. The end of the work day presents their cue to drive to the gym and workout instead of driving home. For others, the cue may be the alarm clock going off in the morning signaling that it is time to go for a run or a bike ride. Some research suggests that it may take a month or longer of repeated behavior before a cue reliably and automatically triggers a behavior; sticking with the same time of day might help initially, Phillips said. The most common cues used with interventions are external, she added. But what works best might vary from person to person. Internal cues, such as a feeling that you need to move after sitting for several hours at your desk, form the strongest habits, Phillips speculates, but are harder to train in people and must develop over time. The study is the first to explore the importance of different habit components in predicting exercise frequency. Phillips and Benjamin Gardner, King's College London, asked 118 healthy adults to rate their exercise instigation and execution habit strength. They then tracked how often they exercised over the course of the month. Approximately 25 percent of participants were overweight or obese. Around 5 percent reported not exercising, while nearly 50 percent said they had regularly exercised longer than 12 months. Finding a cue that works for you While the study found execution habit had no effect on exercise frequency, after controlling for instigation habit, Phillips stressed it still may be an effective option for some people starting a new routine. For anyone who is new to exercise or uncomfortable going to the gym, following the same routine can help build self-confidence at the activity and being active in general. However, for others the repetitiveness of sticking to a specific routine may be detrimental. "This study shows that you don't have to be afraid of trying new things. You can have an instigation habit and try new types of exercise without worrying about losing the habit," Phillips said. "It might be important for people just starting out to do the same thing until they realize they can do this, but in the long-term there does not seem to be a benefit of doing the same things over and over again." Phillips says more research is needed to determine what cues work best. "I would caution people to not draw too many personal conclusions from this research because it is so preliminary," she said. "This doesn't mean that one way is necessarily bad or this is the way you have to do it. It's really just the first clue that maybe what we have been doing isn't right for everyone. And, I think it's hopeful that the research shows you can keep up an 'exercise habit' without having to stick to the same boring activities over time." Story Source: The above post is reprinted from materials provided by Iowa State University. Note: Materials may be edited for content and length. Journal Reference: L. Alison Phillips, Benjamin Gardner. Habitual Exercise Instigation (vs. Execution) Predicts Healthy Adults’ Exercise Frequency.. Health Psychology, 2015; DOI: 10.1037/hea0000249

Early-age exercise in mice has positive effects on adult levels of voluntary exercise

 

Theodore Garland is a professor of biology at UC Riverside. Credit: CNAS, UC Riverside.  What impact can exercise done early in life have on the propensity for exercising during the adult years? A team of researchers at the University of California, Riverside did experiments on mice in the lab to find out. Specifically, they evaluated the effects of early exercise on adult physical activity, body mass, food consumption and circulating leptin levels. They found that early-age exercise in mice has positive effects on adult levels of voluntary exercise in addition to reducing body mass -- results that may have relevance for the public policy debates concerning the importance of physical education for children. "These results may have implications for the importance of regular physical education in elementary and middle schools," said Theodore Garland, a professor of biology, who led the research project. "If kids exercise regularly through the school years, then they may be more likely to exercise as adults, which could have far-reaching positive effects on human health and well-being. "Modest levels of exercise can perhaps lower body mass without necessarily triggering homeostatic compensatory responses in food intake. If true, and if this relationship exists in humans, then it could prove of value for ultimately determining recommended daily exercise criteria." Study results appear online in Physiology & Behavior. The researchers conducted their experiments on male mice, half of which were selectively bred for high voluntary wheel running (high runners), the rest serving as the control. Half of the high runners and half of the control mice were allowed wheel access when they were about 24 days old for a total of 21 days, which got the mice through puberty. The rest of the mice were given no wheel access. After three weeks the researchers removed the wheels for seven weeks. Then, they gave all the mice wheel access for about two weeks. They continued to monitor the mice's cage activity, food consumption and body mass. They found increased adult wheel running on both the high runners and the control lines of mice during the first of the two weeks of adult testing. "Although the positive effect of early-life exercise lasted for only one week, it is important to note that one week in the life of a mouse is equivalent to about nine months for humans," Garland said. "Our results suggest that any positive effects of early-life exercise on adult exercise propensity will require reinforcement and maintenance if they are to be long-lasting." His team of researchers found, too, that all mice that had access to early exercise were lighter in weight than their non-exercised counterparts. Garland explained that, in general, exercise will stimulate appetite sooner or later. However, it is possible that certain types of exercise, engaged in for certain durations or at certain moderate levels, might not stimulate appetite much, if at all, at least in some individuals. "If we could understand what sorts of exercise these might be, then we might be able to tailor exercise recommendations in a way that would bring the benefits of exercise without the compensatory increases in appetite that usually occur, hence leading to better prospects for weight loss," he said. Garland was joined in the study by Wendy Acosta, Thomas H. Meek, Heidi Schutz, Elizabeth M. Dlugosz and Kim T. Vu. Meek is now at the University of Washington; Schutz is at Pacific Lutheran University, Wash.; and Dlugosz is at the University of Tennessee. A grant to Garland from the National Science Foundation supported the study.

Moderate exercise helps prevent gestational diabetes, reduce weight gain during pregnancy

 

Women who exercise during pregnancy are less likely to have gestational diabetes, and the exercise also helps to reduce maternal weight gain, finds a study published on 3 June 2015 in BJOG: an International Journal of Obstetrics and Gynaecology. Gestational diabetes is one of the most frequent complications of pregnancy. It is associated with an increased risk of serious disorders such as pre-eclampsia, hypertension, preterm birth, and with induced or caesarean birth. It can have long term effects on the mother including long term impaired glucose tolerance and type 2 diabetes. The children of mothers with gestational diabetes are more likely to become overweight or obese and have a higher risk of developing diabetes themselves. Gaining more weight than is recommended during pregnancy carries similar risks, and these women are also less likely to lose the excess weight after the baby is born. In this systematic review, the research team from Spain looked at the results of enrolling healthy pregnant women, who did little or no exercise, into exercise programmes. Analysis of 13 trials, involving more than 2,800 women, found that exercise reduced the risk of gestational diabetes by more than 30% -- for women who exercised throughout pregnancy this was even greater (36%). This effect was strongest for women who combined toning, strength, flexibility and aerobic exercise. Exercise was also helpful in reducing excessive weight gain -- those who exercised were on average a kilogram lighter. This held true for the weight gain even if the exercise programme was started in the second trimester of pregnancy. Gema Sanabria- Martinez, from Virgen de la Luz Hospital and lead author of the study, said, "Exercise is not something to be feared during pregnancy -- the moderate levels of exercise used in these studies had significantly positive effects on health and were found to be safe for both mother and baby." Mike Marsh, BJOG Deputy Editor-in-chief added, "This careful analysis of previous studies shows a beneficial effect of exercise on healthy pregnant women who ordinarily did little or no exercise. It may influence recommendations for exercise in pregnancy in such women. Further studies are needed to establish whether this effect is seen in all pregnant women." Story Source: The above story is based on materials provided by Wiley. Note: Materials may be edited for content and length. Journal Reference: G Sanabria-Martínez, A García-Hermoso, R Poyatos-León, C Álvarez-Bueno, M Sánchez-López, V Martínez-Vizcaíno. Effectiveness of physical activity interventions on preventing gestational diabetes mellitus and excessive maternal weight gain: a meta-analysis. BJOG: An International Journal of Obstetrics & Gynaecology, 2015; DOI: 10.1111/1471-0528.13429

Exercise protects the heart via nitric oxide, researchers discover

 

May 5, 2011 Emory University Exercise both reduces the risk of a heart attack and protects the heart from injury if a heart attack does occur. For years, doctors have been trying to dissect how this second benefit of exercise works, with the aim of finding ways to protect the heart after a heart attack. Researchers have identified the ability of the heart to produce and store nitric oxide as an important way in which exercise protects the heart from injury. Exercise both reduces the risk of a heart attack and protects the heart from injury if a heart attack does occur. For years, doctors have been trying to dissect how this second benefit of exercise works, with the aim of finding ways to protect the heart after a heart attack. Researchers at Emory University School of Medicine have identified the ability of the heart to produce and store nitric oxide as an important way exercise protects the heart from injury. Nitric oxide, a short-lived gas generated within the body, turns on chemical pathways that relax blood vessels to increase blood flow and activate survival pathways. Both the chemical nitrite and nitrosothiols, where nitric oxide is attached to proteins via sulfur, appear to act as convertible reservoirs for nitric oxide in situations where the body needs it, such as a lack of blood flow or oxygen. The Emory team's results, published online in the journal Circulation Research, strengthen the case for nitrite and nitrosothiols as possible protectants from the damage of a heart attack. The first author is John Calvert, PhD, assistant professor of surgery at Emory University School of Medicine. The senior author is David Lefer, PhD, professor of surgery at Emory University School of Medicine and director of the Cardiothoracic Research Laboratory at Emory University Hospital Midtown. Collaborators included scientists at University of Colorado, Boulder, and Johns Hopkins University. "Our study provides new evidence that nitric oxide generated during physical exercise is actually stored in the bloodstream and heart in the form of nitrite and nitrosothiols. These more stable nitric oxide intermediates appear to be critical for the cardioprotection against a subsequent heart attack," Lefer says. Timing is key -- the benefits of exercise don't last In experiments with mice, the researchers showed that four weeks of being able to run on a wheel protected them from having a coronary artery was blocked; the amount of heart muscle damaged by the blockage was less after the exercise period. Importantly, the mice are still protected a week after the wheel is taken away. The researchers found that voluntary exercise boosted levels of an enzyme that produces nitric oxide (eNOS, endothelial nitric oxide synthase). Moreover, the levels of eNOS in heart tissue, and nitrite and nitrosothiols in the blood as well as heart tissue, stayed high for a week after exercise ceased, unlike other heart enzymes stimulated by exercise. The protective effects of exercise did not extend beyond four weeks after the exercise period was over, when nitrite and nitrosothiols in the heart returned to baseline. In mice that lack the eNOS enzyme, exercise did not protect the heart from a coronary blockage, although these mice appeared to lack the ability to exercise as much as normal mice. Another molecule that appears to be important for the benefits of exercise is the beta-3-adrenergic receptor, which allows cells to respond to the hormones epinephrine and norepinephrine. All of the beneficial effects of voluntary exercise are lost in mice that are deficient in this receptor. One of the effects of stimulating the receptor appears to be activating eNOS. Additional animal studies are currently underway in Lefer's lab to determine the potential benefit of beta-3-adrenergic receptor activating drugs following a heart attack. The research was supported by the American Diabetes Association, the National Institutes of Health and the Carlyle Fraser Heart Center of Emory University Hospital Midtown. Story Source: The above story is based on materials provided by Emory University. Note: Materials may be edited for content and length. Journal Reference: J. W. Calvert, M. Elston, J. Pablo Aragon, C. K. Nicholson, B. F. Moody, R. L. Hood, A. Sindler, S. Gundewar, D. R. Seals, L. A. Barouch, D. J. Lefer. Exercise Protects Against Myocardial Ischemia-Reperfusion Injury via Stimulation of β3-Adrenergic Receptors and Increased Nitric Oxide Signaling: Role of Nitrite and Nitrosothiols. Circulation Research, 2011; DOI: 10.1161/CIRCRESAHA.111.241117

Exercise: A drug-free approach to lowering high blood pressure

 

Having high blood pressure and not getting enough exercise are closely related. Discover how small changes in your daily routine can make a big difference. By Mayo Clinic Staff Heart-Healthy Living Your risk of high blood pressure (hypertension) increases with age, but getting some exercise can make a big difference. And if your blood pressure is already high, exercise can help you control it. Don't think you've got to run a marathon or join a gym. Instead, start slow and work more physical activity into your daily routine. How exercise can lower your blood pressure How are high blood pressure and exercise connected? Regular physical activity makes your heart stronger. A stronger heart can pump more blood with less effort. If your heart can work less to pump, the force on your arteries decreases, lowering your blood pressure. Becoming more active can lower your systolic blood pressure — the top number in a blood pressure reading — by an average of 4 to 9 millimeters of mercury (mm Hg). That's as good as some blood pressure medications. For some people, getting some exercise is enough to reduce the need for blood pressure medication. If your blood pressure is at a desirable level — less than 120/80 mm Hg — exercise can help keep it from rising as you age. Regular exercise also helps you maintain a healthy weight, another important way to control blood pressure. But to keep your blood pressure low, you need to keep exercising. It takes about one to three months for regular exercise to have an impact on your blood pressure. The benefits last only as long as you continue to exercise. How much exercise do you need? Flexibility and strengthening exercises such as lifting weights are an important part of an overall fitness plan, but it takes aerobic activity to control high blood pressure. And you don't need to spend hours in the gym every day to benefit. Simply adding moderate physical activities to your daily routine will help. Any physical activity that increases your heart and breathing rates is considered aerobic exercise, including: Household chores, such as mowing the lawn, raking leaves or scrubbing the floor Active sports, such as basketball or tennis Climbing stairs Walking Jogging Bicycling Swimming The American Heart Association recommends you get at least 150 minutes of moderate exercise, 75 minutes of vigorous exercise or a combination of both each week. Aim for at least 30 minutes of aerobic activity most days of the week. If you can't set aside that much time at once, remember that shorter bursts of activity count, too. You can break up your workout into three 10-minute sessions of aerobic exercise and get the same benefit as one 30-minute session. Weight training and high blood pressure Weight training can cause a temporary increase in blood pressure during exercise. This increase can be dramatic — depending on how much weight you lift. But, weightlifting can also have long-term benefits to blood pressure that outweigh the risk of a temporary spike for most people. If you have high blood pressure and want to include weight training in your fitness program, remember: Learn and use proper form when lifting to reduce the risk of injury. Don't hold your breath. Holding your breath during exertion can cause dangerous spikes in blood pressure. Instead, breathe easily and continuously during each lift. Lift lighter weights more times. Heavier weights require more strain, which can cause a greater increase in blood pressure. You can challenge your muscles with lighter weights by increasing the number of repetitions you do. Listen to your body. Stop your activity right away if you become severely out of breath or dizzy or if you experience chest pain or pressure. If you'd like to try weight training exercises, make sure you have your doctor's OK.

Sitting for long periods increases risk of disease and early death, regardless of exercise

 

The amount of time a person sits during the day is associated with a higher risk of heart disease, diabetes, cancer, and death, regardless of regular exercise. The amount of time a person sits during the day is associated with a higher risk of heart disease, diabetes, cancer, and death, regardless of regular exercise, according to a review study published today in the Annals of Internal Medicine. "More than one half of an average person's day is spent being sedentary -- sitting, watching television, or working at a computer," said Dr. David Alter, Senior Scientist, Toronto Rehab, University Health Network (UHN), and Institute for Clinical Evaluative Sciences. "Our study finds that despite the health-enhancing benefits of physical activity, this alone may not be enough to reduce the risk for disease." The meta-analysis study reviewed studies focused on sedentary behaviour. The lead author is Avi Biswas, PhD candidate, Toronto Rehab, UHN and the Institute of Health Policy, Management and Evaluation, University of Toronto, and the senior author is Dr. Alter, who is also Associate Professor of Medicine, University of Toronto. The authors found the negative effects of sitting time on health, however, are more pronounced among those who do little or no exercise than among those who participate in higher amounts of exercise. "The findings suggest that the health risk of sitting too much is less pronounced when physical activity is increased," said Biswas. "We need further research to better understand how much physical activity is needed to offset the health risks associated with long sedentary time and optimize our health." Future research will help determine what interventions, in addition to physical activity, are effective against the health risk of sedentary time. "Avoiding sedentary time and getting regular exercise are both important for improving your health and survival," said Dr. Alter. "It is not good enough to exercise for 30 minutes a day and be sedentary for 23 and half hours." In the interim, Dr. Alter underlines strategies people can use to reduce sitting time. The target is to decrease sedentary time by two to three hours in a 12-hour day. "The first step is to monitor sitting times -- once we start counting, we're more likely to change our behaviour," said Dr. Alter. "Next is setting achievable goals and finding opportunities to incorporate greater physical activity -- and less time sitting -- into your daily life. For example, at work, stand up or move for one to three minutes every half hour; and when watching television, stand or exercise during commercials." Dr. Alter's work is supported by a career-investigator award with the Heart and Stroke Foundation, Ontario Provincial Office; and a Research Chair in Cardiovascular Prevention and Metabolic Rehabilitation at Toronto Rehab, UHN. Story Source: The above story is based on materials provided by University Health Network (UHN). Note: Materials may be edited for content and length. Journal Reference: Aviroop Biswas, Paul I. Oh, Guy E. Faulkner, Ravi R. Bajaj, Michael A. Silver, Marc S. Mitchell, and David A. Alter. Sedentary Time and Its Association With Risk for Disease Incidence, Mortality, and Hospitalization in Adults: A Systematic Review and Meta-analysis. Annals of Internal Medicine, 2015 DOI: 10.7326/M14-1651

How harmful is too much sitting?

 

Sitting for long periods of time has been linked to a number of health concerns, including obesity, heart disease and even cancer. Don't believe it? Stand up and read on. It’s time to step away from the computer and read this: According to one study, people who spend more than four hours a day in front of a screen have a higher risk of early death in general and a higher risk of events related to heart disease, such as chest pain or heart attack. But sitting in front of the TV isn't the only concern. Any extended sitting — such as behind a desk at work or behind the wheel — can be harmful. What's more, even fitting in some moderate or vigorous activity doesn't seem to significantly offset the risk of sitting most of the time. The solution? Sit less and move more overall. You might start by simply standing rather than sitting whenever you have the chance. For example: Stand while talking on the phone or eating lunch. If you work at a desk for long periods of time, try a standing desk — or improvise with a high table or counter. Better yet, think about ways to walk while you work: Walk laps with your colleagues rather than gathering in a conference room for meetings. Position your work surface above a treadmill — with a computer screen and keyboard on a stand or a specialized treadmill-ready vertical desk — so that you can be in motion throughout the day. The impact of movement — even leisurely movement — can be profound. For starters, you'll burn more calories. This can lead to weight loss and increased energy. Plus, the muscle activity needed for standing and other movement seems to trigger important reactions related to the breakdown of fats and sugars within the body. When you sit, these responses stall — and your health risks increase. When you're standing or actively moving, you kick the processes back into action.

Walking: Trim your waistline, improve your health

 

Can you really walk your way to fitness? You bet! Get started today. Know the benefits Physical activity doesn't need to be complicated. Something as simple as a daily brisk walk can help you live a healthier life. For example, regular brisk walking can help you: Maintain a healthy weight Prevent or manage various conditions, including heart disease, high blood pressure and type 2 diabetes Strengthen your bones Lift your mood Improve your balance and coordination The faster, farther and more frequently you walk, the greater the benefits. Consider your technique Turning your normal walk into a fitness stride requires good posture and purposeful movements. Ideally, here's how you'll look when you're walking: Your head is up. You're looking forward, not at the ground. Your neck, shoulders and back are relaxed, not stiffly upright. You're swinging your arms freely with a slight bend in your elbows. A little pumping with your arms is OK. Your stomach muscles are slightly tightened and your back is straight, not arched forward or backward. You're walking smoothly, rolling your foot from heel to toe. Plan your routine As you start your walking routine, remember to: Get the right gear. Choose shoes with proper arch support, a firm heel and thick flexible soles to cushion your feet and absorb shock. If you walk outdoors when it's dark, wear bright colors or reflective tape for visibility. Choose your course carefully. If you'll be walking outdoors, avoid paths with cracked sidewalks, potholes, low-hanging limbs or uneven turf. Warm up. Walk slowly for five to 10 minutes to warm up your muscles and prepare your body for exercise. Cool down. At the end of your walk, walk slowly for five to 10 minutes to help your muscles cool down. Stretch. After you cool down, gently stretch your muscles. If you'd rather stretch before you walk, remember to warm up first.

Chronic kidney disease: Exercise provides clear benefits

 

November 15, 2014

American Society of Nephrology (ASN)

Simple exercises can help improve the health of patients with kidney disease, experts say. Heart disease is the leading cause of death in patients with chronic kidney disease (CKD). Because exercise capacity is significantly reduced in CKD patients, experts examined the effect of 12 months of exercise training on kidney function and measures of heart disease risk in patients with progressive CKD stages 3-4.

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Simple exercises can help improve the health of patients with kidney disease, according to studies that will be presented at ASN Kidney Week 2014 November 11-16 at the Pennsylvania Convention Center in Philadelphia, PA.

Heart disease is the leading cause of death in patients with chronic kidney disease (CKD). Because exercise capacity is significantly reduced in CKD patients, Sharlene Greenwood, MD (King's College Hospital, in London) and her colleagues examined the effect of 12 months of exercise training on kidney function and measures of heart disease risk in patients with progressive CKD stages 3-4. For the study, 20 patients were randomized to a rehabilitation group (REHAB, n = 10) that received exercise training (3 times per week) or standard care (UC, n = 10). A total of 18 participants completed the study (8 from the REHAB group and 10 from the UC group).

The researchers found that 12 months of exercise-based rehabilitation significantly slowed the rate of kidney function decline and improved cardio-respiratory fitness compared with standard care. "Exercise-based rehabilitation has the potential to be a kidney-protective therapy for patients with progressive stages 3-4 CKD, and larger studies are planned," said Dr. Greenwood. "Exercise, besides protecting the kidneys, also will improve fitness, general health, and quality of life and has the potential to reduce cardiovascular risk, a major cause of mortality and morbidity in patients with CKD."

In another study, Francesca Mallamaci, MD (National Research Council Institute of Clinical Physiology, in Italy) and her colleagues tested the effectiveness of a low-intensity, easy-to-implement, home exercise program on physical performance in dialysis patients. For the EXCITE trial, 151 patients were instructed to follow the cadence of an inexpensive metronome while walking, while 146 patients maintained their normal physical activity.

After 6 months, performance in a 6-minute walking test improved in the exercise group (with participants walking 41 meters more in that amount of time), but remained unchanged in the control group. A 'sit to stand' test also improved in the exercise group but not in the control group. "A personalized, low-intensity home exercise program improves physical performance in dialysis patients," the investigators concluded. "The simplicity and adaptability of the program make it suitable to the needs of a high-risk population such as the dialysis population."

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Story Source:

The above story is based on materials provided by American Society of Nephrology (ASN). Note: Materials may be edited for content and length.

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Scientists Discovered a Part of Brain that Motivates Us to Exercise

 

Posted By Recail On Friday, September 26, 2014 11:26 PM. Under Fitness Tips, Health Tips

In recent years, there have been many studies about the relationship between your neural messages and motivation for exercise. Scientists have believed that there must be a reason why some people are motivated to exercise, while others don’t feel the need. The claims made by the scientists have finally seen some positive backing.

According to a recent study, scientists discovered that a tiny region in the human brain is responsible for controlling a person’s desire to sprint and participate in some other rewarding activities. The study was conducted on mice, and noted their motivation for running.

The region of brain responsible for this motivation is called Dorsal Medial Habenula. The structure in mice is similar to the region in men. Scientists believe that this region’s ability to regulate motivation and mood should be similar across the two different species.

According to Head Researcher, Seattle Children’s Research Institute, Eric Turner, some significant changes in the physical activity and a person’s inability to enjoy pleasurable or rewarding experiences are two major causes of depression. 

He believes that the brain pathways that play an important role for exercise motivation aren’t well understood. With some new and effective ways to manipulate activity within particular brain areas, researchers plan to develop more effective and targeted treatments for depression. Researchers are positive about developing some effective ways to accomplish these goals without having any impact on the rest of brain activity.

During their research, Eric Turner and other researchers focused on genetically engineered mice. They tried to block various signals from the mice’s Dorsal Medial Habenula. As compared to regular mice who always love to sprint on wheels, genetically engineered mice ran less, and even felt lethargic. As a side note, this is not the first time in the recent past that we explored depression with the aid of mice. A study conducted in 2006 used mice to test the hypothesis that the deficiency of certain proteins, particularly p11, can also lead to depression. The researchers concluded that if the lacking protein was introduced in form of supplements, the mood of the animals significantly improved.

Recently, Turner explained in a press release that the lack of a functioning Dorsal Medial Habenula, the genetically engineered mice acted like couch potatoes. Although these mice were capable of running, they didn’t have the motivation to sprint on wheels.

Eric Turner also explained that these genetically engineered mice didn’t prefer sweetened, delicious drinking water instead of regular water. It’s important to understand that the lack of basic exercise and desire to seek pleasure led to depression in the mice. These mice didn’t care anymore about their health and well being.

The research team also conducted another experiment. In this experiment, researches precisely targeted light to the Dorsal Medial Habenula of the mice. When the mice turned one of the two wheels using their paws, they were able to voluntarily activate the specific region in the brain.

Light exercises

 

Light exercises linked to less disability

Most breast cancer patients may not be getting enough exercise

 

June 9, 2014

Wiley

Physical activity after breast cancer diagnosis has been linked with prolonged survival and improved quality of life, but most participants in a large breast cancer study did not meet national physical activity guidelines after they were diagnosed. Moreover, African-American women were less likely to meet the guidelines than white women. The findings indicate that efforts to promote physical activity in breast cancer patients may need to be significantly enhanced.

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Physical activity after breast cancer diagnosis has been linked with prolonged survival and improved quality of life, but most participants in a large breast cancer study did not meet national physical activity guidelines after they were diagnosed. Moreover, African-American women were less likely to meet the guidelines than white women. Published early online in CANCER, a peer-reviewed journal of the American Cancer Society, the findings indicate that efforts to promote physical activity in breast cancer patients may need to be significantly enhanced.

The US Department of Health and Human Services, as well as the American Cancer Society, recommends that adults engage in at least 150 minutes of moderate-intensity physical activity or 75 minutes of vigorous-intensity physical activity (or an equivalent combination thereof) each week for general health benefits and for chronic disease prevention and management.

Because it's important to understand whether there is capacity for improvement in the physical activity levels of women with breast cancer, Brionna Hair, a doctoral candidate in epidemiology at the University of North Carolina at Chapel Hill, and her colleagues examined levels of and changes in physical activity following breast cancer diagnosis, overall and by race, in a population-based study of breast cancer patients. The study assessed pre- and post-diagnosis physical activity levels in 1,735 women aged 20 to 74 years who were diagnosed with invasive breast cancer between 2008 and 2011 in 44 counties of North Carolina.

The researchers found that only 35 percent of breast cancer survivors met current physical activity guidelines post-diagnosis. A decrease in activity approximately six months after diagnosis was reported by 59 percent of patients, with the average participant reducing activity by 15 metabolic equivalent hours -- equivalent to about five hours per week of brisk walking. When compared with white women, African-American women were about 40 percent less likely to meet national physical activity guidelines post-diagnosis, although their reported weekly post-diagnosis physical activity was not significantly different from that of White women (12 vs 14 metabolic equivalent hours). Ms. Hair noted that it's important to realize that African-American women experience higher mortality from breast cancer than other groups in the United States.

"Medical care providers should discuss the role physical activity plays in improving breast cancer outcomes with their patients, and strategies that may be successful in increasing physical activity among breast cancer patients need to be comprehensively evaluated and implemented," said Ms. Hair.

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Story Source:

The above story is based on materials provided by Wiley. Note: Materials may be edited for content and length.

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Journal Reference:

1. Brionna Y. Hair, Sandi Hayes, Chiu-Kit Tse, Mary Beth Bell, Andrew F. Olshan. Racial differences in physical activity among breast cancer survivors: Implications for breast cancer care. Cancer, 2014; DOI: 10.1002/cncr.28630