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Category: Exercise

Published on Leave a comment on Exercise Has Anti-Inflammatory Effect

Looks like exercise, even 20 minutes of moderate activity such as brisk walking, has beneficial anti-inflammatory health effects. Inflammation is part of the body's normal immune response - it is the body's attempt to heal itself after an injury and tissue damage, and to defend itself against infection from foreign invaders, such as viruses and bacteria.

However, chronic inflammation (e.g., what can occur in obesity, diabetes, and poor lifestyle) can lead to serious health issues and is linked to cancer, heart disease, etc. So lowering chronic (systemic) inflammation is good. From Science Daily:

Exercise ... It does a body good: 20 minutes can act as anti-inflammatory

It's well known that regular physical activity has health benefits, including weight control, strengthening the heart, bones and muscles and reducing the risk of certain diseases. Recently, researchers at University of California San Diego School of Medicine found how just one session of moderate exercise can also act as an anti-inflammatory. The findings have encouraging implications for chronic diseases like arthritis, fibromyalgia and for more pervasive conditions, such as obesity.

The study, recently published online in Brain, Behavior and Immunity, found one 20-minute session of moderate exercise can stimulate the immune system, producing an anti-inflammatory cellular response. The brain and sympathetic nervous system -- a pathway that serves to accelerate heart rate and raise blood pressure, among other things -- are activated during exercise to enable the body to carry out work. Hormones, such as epinephrine and norepinephrine, are released into the blood stream and trigger adrenergic receptors, which immune cells possess. This activation process during exercise produces immunological responses, which include the production of many cytokines, or proteins, one of which is TNF -- a key regulator of local and systemic inflammation that also helps boost immune responses.

The 47 study participants walked on a treadmill at an intensity level that was adjusted based on their fitness level. Blood was collected before and immediately after the 20 minute exercise challenge."Our study shows a workout session doesn't actually have to be intense to have anti-inflammatory effects. Twenty minutes to half-an-hour of moderate exercise, including fast walking, appears to be sufficient," said Hong.

Inflammation is a vital part of the body's immune response. It is the body's attempt to heal itself after an injury; defend itself against foreign invaders, such as viruses and bacteria; and repair damaged tissue. However, chronic inflammation can lead to serious health issues associated with diabetes, celiac disease, obesity and other conditions.

Published on Leave a comment on Focus On Healthy Lifestyle, Not Just On Tests And Screenings

The wonderful blog posts of Dr. John Mandrola (physician, blogger, and columnist at Medscape) are always thoughtful, and this latest points out things a number of studies have pointed out for a while. Which is to stop obsessing or focusing on "preventive tests" and screenings and numbers, and instead focus on a healthy lifestyle - which means getting regular exercise or physical activity, don't smoke cigarettes, maintaining a healthy weight, and eating a healthy diet with lots of fruits, vegetables, nuts, seeds, whole grains, and legumes (think Mediterranean-style diet).

Don't want overdiagnosis and overtreatment (here, here, here, and here). Excerpts from Dr. John M:

I am changing…

The main thing that has changed about me is my views as a doctor, especially when it comes to dealing with people who complain of nothing. Medicine is most pure when we treat people with illness. The infirmed come to us with a problem and we use our intelligence, experience and procedural skills to help them. It’s immensely gratifying. The joy of helping people still negates the stifling burden of administrative nonsense. I’ll do your damn corporate safety modules one more year because helping sick people get well feels so good.

But when people complain of nothing, our first job is to do no harm. I know prevention of disease is better than treating it, but the process of prevention gets dicey. When we prescribe things (screening tests, statins, aspirin, diabetes drugs etc) to people who complain of nothing, we should have the highest evidence these therapies deliver benefit. Too often, we cite eminence rather than evidence.

I’ve come to believe the medical profession is too paternalistic, too arrogant. I fear the medicalization of the human condition. These days, I order fewer tests. Medical tests put people into the “system,” on the metaphorical train of healthcare. This train accelerates quickly, and it’s often hard to get off. Even a simple echo scares me. I could tell you stories.

More often than not, I tell patients to stop checking their “numbers.” If they insist on health numbers, I favor three–the scale, the belt size and a Timex to measure walking speed.

A 2002 article from Dr. David Sackett (a pioneer of evidence-based medicine) perfectly captures my views on preventive medicine. It’s called The Arrogance of Preventive Medicine. It’s worth a look, now more than ever.

Published on Leave a comment on Heart Attacks Run In The Family? Healthy Lifestyle Can Really Reduce Risk

 Image result for human heart in human body wikipedia Heart attacks run in the family? Does this mean you are doomed to also have a heart attack? Well, the good news from a large study is that a healthy lifestyle (with at least 3 of these 4 behaviors: not currently smoking, not being obese, regular physical activity at least once per week, and eating a good diet)  lowers the risk of a heart attack by nearly 50% even in those with a high genetic risk for heart attacks. (This is compared to those with an unhealthy lifestyle, which is none or only one healthy behavior.)  In this study a healthy diet was one with lots of fruits, nuts, vegetables, whole grains, fish, and dairy products, and a reduced amount of refined grains, processed meats, red meat, sugar-sweetened beverages, and trans fats.

The researchers also reversed the question and asked: "If you happen to inherit good genes, can a bad lifestyle offset that? We actually found yes." The risk of heart attack is also reduced nearly 50% in those people with good genes and a good lifestyle. BOTTOM LINE: Healthy lifestyle counts, no matter whether heart disease and heart attacks run in the family or not. There is an interaction between the two, From Science Daily:

Following a healthy lifestyle can greatly reduce genetic heart attack risk

It is well known that following a healthy lifestyle -- not smoking, avoiding excess weight and getting regular exercise -- can reduce the risk of heart disease. But what about people who have inherited gene variants known to increase risk? A study led by Massachusetts General Hospital (MGH) investigators has found that, even among those at high genetic risk, following a healthy lifestyle can cut in half the probability of a heart attack or similar event. 

"The basic message of our study is that DNA is not destiny," says Sekar Kathiresan, MD...."Many individuals -- both physicians and members of the general public -- have looked on genetic risk as unavoidable, but for heart attack that does not appear to be the case."  

In order to investigate whether a healthy lifestyle can mitigate genetic risk, the multi-institutional research team analyzed genetic and clinical data from more than 55,000 participants in four large-scale studies. Three of these studies....followed participants for up to 20 years. Each participant in the current analysis was assigned a genetic risk score....The investigators used four AHA-defined lifestyle factors -- no current smoking; lack of obesity (defined as a body mass index less than 30); physical exercise at least once a week; and a healthy dietary pattern -- to determine a lifestyle score, whether participants had a favorable (three or four healthy factors), intermediate (two factors) or unfavorable (one or no healthy factors) lifestyle.

Across all three prospective studies, a higher genetic risk score significantly increased the incidence of coronary events -- as much as 90 percent in those at highest risk. While known risk factors such as a family history and elevated LDL cholesterol were also associated with an elevated genetic risk score, genetic risk was the most powerful contributor to cardiac risk. Similarly, each healthy lifestyle factor reduced risk, and the unfavorable lifestyle group also had higher levels of hypertension, diabetes and other known risk factors upon entering the studies.

Within each genetic risk category, the presence of lifestyle factors significantly altered the risk of coronary events to such an extent that following a favorable lifestyle could reduce the incidence of coronary events by 50 percent in those with the highest genetic risk scores. Among participants in the BioImage study, both genetic and lifestyle factors were independently associated with levels of calcium-containing plaque in the coronary arteries, and healthy lifestyle factors were associated with less extensive plaque within each genetic risk group. [Original study]

Published on Leave a comment on Why Eat More Than Ten Servings of Fruits and Vegetables Daily?

  Eating lots of fruits and vegetables (more than 10 servings a day!)  is linked to better cognitive functioning in both normal weight and overweight adults (both young and older adults), and may delay the onset of cognitive decline that occurs with aging and also dementia. Overweight and obese older adults with a daily fruit and vegetable consumption of less than 5 servings generally had worse cognitive functioning. Higher levels of physical activity and higher daily fruit and vegetable consumption were both associated with better cognitive functioning. Cognitive functioning generally refers to a person’s ability to reason and think, the mental processes needed to gather and process information, and all aspects of language and memory.

The York University researchers found that fruit and vegetable consumption, physical activity, and BMI or body mass index (normal, overweight, obese) all appear to interact in how a person mentally functions (cognitive functioning), especially as they age. The ideal goal as one ages is to preserve the mind. It appears that eating lots of fruits and vegetables daily (10 or more servings), being physically active (this includes daily walks), and being a healthy weight help with this goal. It helps to also be highly educated (or read books?) so that the brain has a "cognitive reserve",

Why is daily fruit and vegetable consumption (FVC) good for cognitive functioning and the brain? Studies find that daily consumption of fruits and vegetables is strongly associated with a reduced risk of cardiovascular disease, cancer, diabetes and age-related declines. They appear to be "protective" against cognitive decline. The study researchers point out that fruits and vegetables contain high quantities of vitamin C and E, fiber, micronutrients, flavonoids, beta-carotenes and other classes of phytochemicals. These are important in various ways: "they modulate detoxifying enzymes, stimulate the immune system, modulate cholesterol synthesis, and act as antibacterial, antioxidant or neuroprotective agents." NOTE: A serving of fruit is generally 1 medium fruit or 1/2 cup of fruit. A serving of vegetables is 1 cup of raw leafy greens or 1/2 cup of other vegetables. From Medical Xpress:

Healthy living linked to higher brain function, delay of dementia

It's tempting to dip into the leftover Halloween treats, but new research out of York University has found eating plenty of fruits and vegetables, combined with regular exercise, leads to better cognitive functioning for younger and older adults, and may delay the onset of dementia. York U post-doctoral fellow Alina Cohen and her team, including Professors Chris I. Ardern and Joseph Baker, looked at cross-sectional data of 45,522 participants, age 30 to 80+, from the 2012 annual component of the Canadian Community Health Survey.

What they found was that for those who are normal weight or overweight, but not obese, eating more than 10 servings of fruit and vegetable daily was linked to better cognitive functioning. When moderate exercise was added, those eating less than five servings, reported better cognitive functioning. Higher levels of physical activity were linked to the relationship between higher daily fruit and vegetable consumption and better cognitive performance. Those with higher body mass indexes, low activity levels and fruit and vegetable consumption were associated with poorer cognitive functioning.

More details from the original study in the Journal of Public Health: Physical activity mediates the relationship between fruit and vegetable consumption and cognitive functioning: a cross-sectional analysis

Results: Higher BMIs, lower PA [physical activity] and FVC [fruit and vegetable consumption] were associated with poorer cognitive functioning. Additionally, PA statistically mediated the relationship between FVC and cognitive function (Sobel test: t = −3.15; P < 0.002); and higher education levels and daily FVC were associated with better cognitive function (P < 0.001). Conclusion: Higher PA levels were associated with better cognitive functioning in younger and older adults. Also, higher daily FVC and education levels were associated with better cognitive scores.

Individuals who were normal weight or overweight and reported a FVC of >10 servings per day reported better cognitive functioning scores than those who reported <10 servings, as well as those individuals with obesity . As well, both active and inactive individuals who reported a FVC of >10 servings per day had better cognitive scores than those who consumed fewer servings. However, in those who were moderately active, individuals with a daily FVC of <5 or 5–10 servings reported better cognitive functioning than those with a daily FVC of 10 or more servings; this may have resulted because of underestimations of the number of servings of fruits and vegetables actually consumed... Thus, increasing FVC and PA levels as well as having a healthy BMI may aid in the delay of cognitive decline.

Results also indicated that higher education levels along with a daily FVC of five or more servings were associated with better cognitive functioning. Education may be assisting in the process of delaying cognitive decline by increasing cognitive reserve, the ability of the human brain to cope with damage by using different brain processes to retain the ability to function well. Cognitive reserve is developed through intellectual stimulation and translates into a higher volume of connections between neurons and stronger rates of cerebral blood flow.

Published on Leave a comment on Youth Football Players Have Brain Changes After One Season

Another study finding brain changes from playing tackle football - this time measurable brain changes were found in boys 8 to 13 years old after just one season of playing football. None of the boys had received a concussion diagnosis during the season. The changes in the white matter of the brain (and detected with magnetic resonance imaging (MRI) were from the cumulative subconcussive head impacts that occur in football - the result of repetitive hits to the head during games and practices.

No one knows if the brains of football players fully recover after the football season. But these findings are worrisome. Especially because last year researchers found that NFL players who had begun playing  football before age 12 had a higher risk of altered brain development, as compared to players who started later (see post). Currently nearly 3 million students participate in youth tackle football programs across the United States. Some are calling for young players to only play flag or touch football, and to only play tackle football starting with the teenage years. From Science Daily:

Brain changes seen in youth football players without concussion

Researchers have found measurable brain changes in children after a single season of playing youth football, even without a concussion diagnosis, according to a new study published online in the journal Radiology.

"Most investigators believe that concussions are bad for the brain, but what about the hundreds of head impacts during a season of football that don't lead to a clinically diagnosed concussion? We wanted to see if cumulative sub-concussive head impacts have any effects on the developing brain," said the study's lead author, Christopher T. Whitlow, M.D., Ph.D., M.H.A., associate professor and chief of neuroradiology at Wake Forest School of Medicine in Winston-Salem, N.C.

The research team studied 25 male youth football players between the ages of 8 and 13. Head impact data were recorded using the Head Impact Telemetry System (HITs), which has been used in other studies of high school and collegiate football to assess the frequency and severity of helmet impacts....The study participants underwent pre- and post-season evaluation with multimodal neuroimaging, including diffusion tensor imaging (DTI) of the brain. DTI is an advanced MRI technique, which identifies microstructural changes in the brain's white matter. 

The brain's white matter is composed of millions of nerve fibers called axons that act like communication cables connecting various regions of the brain. Diffusion tensor imaging produces a measurement, called fractional anisotropy (FA), of the movement of water molecules in the brain and along axons. In healthy white matter, the direction of water movement is fairly uniform and measures high in FA. When water movement is more random, FA values decrease, which has been associated with brain abnormalities in some studies.

The results showed a significant relationship between head impacts and decreased FA in specific white matter tracts and tract terminals, where white and gray matters meet. "We found that these young players who experienced more cumulative head impact exposure had more changes in brain white matter, specifically decreased FA, in specific parts of the brain," Dr. Whitlow said. "These decreases in FA caught our attention, because similar changes in FA have been reported in the setting of mild TBI."

It is important to note that none of the players had any signs or symptoms of concussion."We do not know if there are important functional changes related to these findings, or if these effects will be associated with any negative long-term outcomes," Dr. Whitlow said. "Football is a physical sport, and players may have many physical changes after a season of play that completely resolve. These changes in the brain may also simply resolve with little consequence. However, more research is needed to understand the meaning of these changes to the long-term health of our youngest athletes." [Original study]

Published on Leave a comment on Time To End Heading Of Balls In Soccer?

Image result for soccer ball Many studies have discussed the short-term and long-term harm to the brain from playing tackle football, especially when starting the game at an early age (before the age of 12) , and from getting concussions and sub-concussions. But relatively little has been said about the possibility of similar harm from soccer (see post).

Finally a study looking at the practice of heading the ball in soccer - where yes, the person is directly hitting the soccer ball with his or her head, whether during a game or routine heading practice. Any harm from that? Yes. There were measurable brain function changes in both male and female young adults after heading a soccer ball 20 times during one practice session. While the changes ("short and long term memory function and corticomotor inhibition") were temporary, the researchers were concerned over possible long term brain effects (perhaps similar to those found in football players) when there are many practice sessions and soccer games, over many years. From Science Daily:

Heading a soccer ball causes instant changes to the brain

Researchers from the University of Stirling have explored the true impact of heading a soccer ball, identifying small but significant changes in brain function immediately after routine heading practice. The study from Scotland's University for Sporting Excellence published in EBioMedicine is the first to detect direct changes in the brain after players are exposed to everyday head impacts, as opposed to clinical brain injuries like concussion.

A group of soccer ball players headed a ball 20 times, fired from a machine designed to simulate the pace and power of a corner kick. Before and after the heading sessions, scientists tested players' brain function and memory. Increased inhibition in the brain was detected after just a single session of heading. Memory test performance was also reduced by between 41 and 67 per cent, with effects normalising within 24 hours. Whether the changes to the brain remain temporary after repeated exposure to a soccer ball and the long-term consequences of heading on brain health, are yet to be investigated.

Played by more than 250 million people worldwide, the 'beautiful game' often involves intentional and repeated bursts of heading a ball. In recent years the possible link between brain injury in sport and increased risk of dementia has focused attention on whether soccer ball heading might lead to long term consequences for brain health.

Cognitive neuroscientist Dr Magdalena Ietswaart from Psychology at the University of Stirling, said: "In light of growing concern about the effects of contact sport on brain health, we wanted to see if our brain reacts instantly to heading a soccer ball. Using a drill most amateur and professional teams would be familiar with, we found there was in fact increased inhibition in the brain immediately after heading and that performance on memory tests was reduced significantly.

"Although the changes were temporary, we believe they are significant to brain health, particularly if they happen over and over again as they do in soccer ball heading. With large numbers of people around the world participating in this sport, it is important that they are aware of what is happening inside the brain and the lasting effect this may have." In the study, scientists measured levels of brain function using a basic neuroscience technique called Transcranial Magnetic Stimulation (TMS).  (Original study)

Published on Leave a comment on Time For Doctors To Prescribe Exercise

We all know that exercise is beneficial for health. Research suggests that exercising out in nature is best for several varied reasons -  including that it lowers markers of inflammation, and that it's good for our gut microbiome (community of gut microbes). The following excerpts are written by Dr. John La Puma encouraging other doctors to prescribe exercise for their patients and why.

An important message of his is that exercise is more important than a drug prescription for a number of conditions, including diabetes prevention, reducing the risk of recurrence of several cancers (he mentions breast cancer, but it also holds for prostate cancer). While exercising and walking out in nature may be best, any exercise anywhere is better than no exercise. (Other posts on exercise as prescription medicine are here and here; and check the category exercise for all exercise research posts).

From Medscape: Rx: Exercise Daily -- Outdoors. Doctor's Orders

With dazzling Olympic feats on display all summer, too many of my patients are still literally immobilized. Medically, sitting too long shuts off the enzyme lipoprotein lipase. In people who are sedentary, the enzyme doesn't break down fat to create energy, like it should. But medical prescription for exercise has lagged even the slowest runner. Why? Some reasons are time, training, and money. Time especially is a scarce commodity: The average clinician visit lasts just 20 minutes. Fitness is a shamefully small part of medical training. And as doctors, we don't get paid for discussing exercise, let alone monitoring a prescription and assessing the response. 

Finally, there are practical reasons. Clinicians find it difficult to persuade patients that exercise is more effective than medication for any number of conditions, including stroke recovery, diabetes prevention, and treatment of low back pain. Regular exercise reduces the risk for recurrent breast cancer by approximately 50%. Given all these reasons, it's easy to see why fitness prescriptions are seldom more than an afterthought. Yet even without formally prescribing the frequency, intensity, time, and type of exercise, clinicians can speak with patients and families about fitness in inspiring, life-changing ways.

Because clinicians have a secret weapon to use that most people don't even know about—location. Exercising in nature (in sight of and preferably near water or greenery, whether a deserted beach or an urban park) is better. Walking city streets and the office itself can be harder on your health than you think. In both environments, your attention is demanded and directed—sometimes by digital interruptions, sometimes by vehicles, toxins, or duties. In nature, your attention is drawn, not pushed, to a variety of often unexpected but not unpleasant sounds, colors, aromas, textures, and forms.

A recent Stanford study of nature therapy showed significantly reduced rumination after a 90-minute walk in nature, compared with a 90-minute walk through an urban environment. On MRI, "nature walkers" showed lower activity in an area of the brain linked to risk for mental illness, the subgenual prefrontal cortex, compared with "urban walkers." In other words, nature offers a sense of something bigger than ourselves on which to focus. MRIs show the way the brain changes when that sense occurs to us.

Exercising in nature may improve a person's immune system by enriching the diversity in the microbiota. Microbiota buffer the immune system against chronic stress-related disease. They appear to act as a hormone-producing organ, not simply a collection of beneficial bacteria. Microbiota are sensitive and responsive to physical environmental changes as well as dietary ones. So, exercise in nature may favorably boost microbiota.

And finally, exercise in nature is clinically preferred and calming. A Norwegian study showed that exercise in nature and in view of nature improves both mood and diastolic blood pressure vs exercise without nature. A Chinese study showed higher energy levels, and lower levels of interleukin-6 and tumor necrosis factor (both markers of inflammation), in a forest walking group compared with an urban exercising group. A British study showed significantly improved mood and self-esteem with "green" exercise, with the largest benefits from 5-minute engagements. Five minutes!

Of course, there are areas in our country and world in which it is dangerous to walk, never mind exercise. It may not be as easy to generate sweat and intensity with outdoor exercise as it is with indoor exercise. It may be stormy, or baking hot, or otherwise harsh outside, and the cool recesses of one's own bedroom or the gym may be just perfect for you today. And with the 2013 total cost of inactivity estimated at $24.7 billion for the United States, and with the public sector bearing almost one half of that expense, any exercise anywhere is better than none.  Yet physicians have a therapeutic tool few others in our culture wield—a prescription pad—and we have every patient's attention, at least for a few minutes. Patients try harder when doctors advise them about fitness. 

Published on Leave a comment on Stopping All Exercise and Blood Flow In the Brain

What happens to your brain when you stop exercising? The results of this Univ. of Maryland study should be a wake up call for those who are not quite convinced of exercise's health benefits to the brain. The researchers examined cerebral blood flow in athletes (ages 50-80 years, who were recruited from running clubs) before and after a 10-day period during which they stopped all exercise. Using MRI brain imaging techniques, they found a significant decrease in blood flow to several brain regions important for cognitive health, including the hippocampus, after they stopped their exercise routines.

As the researchers pointed out: "...the take home message is simple -- if you do stop exercising for 10 days, just as you will quickly lose your cardiovascular fitness, you will also experience a decrease in blood brain flow." The only good news was that there were no differences on cognitive measures both before and after stopping exercise for 10 days. From Science Daily:

Use it or lose it: Stopping exercise decreases brain blood flow

We all know that we can quickly lose cardiovascular endurance if we stop exercising for a few weeks, but what impact does the cessation of exercise have on our brains? New research led by University of Maryland School of Public Health researchers examined cerebral blood flow in healthy, physically fit older adults (ages 50-80 years) before and after a 10-day period during which they stopped all exercise. Using MRI brain imaging techniques, they found a significant decrease in blood flow to several brain regions, including the hippocampus, after they stopped their exercise routines.

"We know that the hippocampus plays an important role in learning and memory and is one of the first brain regions to shrink in people with Alzheimer's disease," says Dr. J. Carson Smith, associate professor of kinesiology and lead author of the study, which is published in Frontiers in Aging Neuroscience in August 2016. "In rodents, the hippocampus responds to exercise training by increasing the growth of new blood vessels and new neurons, and in older people, exercise can help protect the hippocampus from shrinking. So, it is significant that people who stopped exercising for only 10 days showed a decrease in brain blood flow in brain regions that are important for maintaining brain health."

The study participants were all "master athletes," defined as people between the ages of 50 and 80 (average age was 61) who have at least 15 years history of participating in endurance exercise and who have recently competed in an endurance event. Their exercise regimens must have entailed at least four hours of high intensity endurance training each week. On average, they were running 36 miles (59 km) each week or the equivalent of a 10K run a day! Not surprisingly, this group had a V02 max (maximum volume of oxygen) above 90% for their age. This is a measure of the maximal rate of oxygen consumption of an individual and reflects their aerobic physical fitness.

Dr. Smith and colleagues measured the velocity of blood flow in brain with an MRI scan while they were still following their regular training routine (at peak fitness) and again after 10 days of no exercise. They found that resting cerebral blood flow significantly decreased in eight brain regions, including the areas of the left and right hippocampus and several regions known to be part of the brain's "default mode network" -- a neural network known to deteriorate quickly with a diagnosis of Alzheimer's disease. This information adds to the growing scientific understanding of the impact of physical activity on cognitive health.

Published on Leave a comment on Lifestyle Factors Influence Protein Buildups Linked to Alzheimer’s

  Again, another study showing the importance of lifestyle factors in the development of protein buildups in the brain that are associated with the onset of Alzheimer's disease. Specifically, the study found that each one of several lifestyle factors—a healthy body mass index, physical activity and a Mediterranean diet, were linked to lower levels of plaques and tangles on brain scans in people who already had mild memory changes, (but not dementia). Other posts discussing Mediterranean diet and brain health (brain volume, etc.) are here, here, and here. Activity levels and brain health posts are here, here, and here. From Medical Xpress:

Diet and exercise can reduce protein build-ups linked to Alzheimer's

A study by researchers at UCLA's Semel Institute for Neuroscience and Human Behavior has found that a healthy diet, regular physical activity and a normal body mass index can reduce the incidence of protein build-ups that are associated with the onset of Alzheimer's disease.

In the study, 44 adults ranging in age from 40 to 85 (mean age: 62.6) with mild memory changes but no dementia underwent an experimental type of PET scan to measure the level of plaque and tangles in the brain. Researchers also collected information on participants' body mass index, levels of physical activity, diet and other lifestyle factors. Plaque, deposits of a toxic protein called beta-amyloid in the spaces between nerve cells in the brain; and tangles, knotted threads of the tau protein found within brain cells, are considered the key indicators of Alzheimer's.

The study found that each one of several lifestyle factors—a healthy body mass index, physical activity and a Mediterranean diet—were linked to lower levels of plaques and tangles on the brain scans. (The Mediterranean diet is rich in fruits, vegetables, legumes, cereals and fish and low in meat and dairy, and characterized by a high ratio of monounsaturated to saturated fats, and mild to moderate alcohol consumption.)

"The fact that we could detect this influence of lifestyle at a molecular level before the beginning of serious memory problems surprised us," said Dr. David Merrill, the lead author of the study, which appears in the September issue of the American Journal of Geriatric Psychiatry.

Earlier studies have linked a healthy lifestyle to delays in the onset of Alzheimer's. However, the new study is the first to demonstrate how lifestyle factors directly influence abnormal proteins in people with subtle memory loss who have not yet been diagnosed with dementia, Merrill said. Healthy lifestyle factors also have been shown to be related to reduced shrinking of the brain and lower rates of atrophy in people with Alzheimer's."The study reinforces the importance of living a healthy life to prevent Alzheimer's, even before the development of clinically significant dementia," Merrill said. 

Published on Leave a comment on Exercise Can Lead To Misdiagnosis of Heart Disease

 The last post pointed out that the importance of high levels of physical activity or exercise in reducing the risk of 5 diseases. Now a study points out that all this exercise (starting at about 3 to 5 hours of exercise per week) can result in the heart becoming enlarged from all this exercise ("athlete's heart"), and that this is totally normal and healthy. The researchers also stressed that doctors should be aware that athlete's heart or "exercise-related cardiac remodeling" can occur not only in professional athletes, but also in those engaging in moderate levels of exercise, and that it not be misdiagnosed as heart disease. From Science Daily:

Regular exercise can lead to heart disease misdiagnosis

Scientists have shown that people who exercise for even a few hours each week can enlarge their hearts. This is a normal and beneficial response to exercise, but until now has only been recognised in athletes. The researchers say that doctors should now consider an individual's activity level before diagnosing common heart conditions.

"It's well known that the hearts of endurance athletes adapt in response to exercise, a phenomenon called 'athlete's heart'. This study is the first to show that healthy adults who do regular exercise may also develop enlarged hearts. As a result, there's a risk that some active adults could be misdiagnosed with heart disease," says Declan O'Regan, of the MRC Clinical Sciences Centre, based at Imperial College London, and one of the lead scientists on the research. The findings were published today in Circulation: Cardiovascular Imaging.

Scientists have not previously known the extent to which the hearts of healthy people adapt to the demands of moderate exercise. Over 1000 people took part in this study, making it one of the largest of its kind. Participants selected one of four possible categories that best represented their activity level over the past year, according to how many hours of exercise they did each week. Around one third of participants reported doing three to five hours of exercise, and the scientists found that one in five of these people had developed an enlarged heart as a result. Similar adaptations were seen in almost half of those who reported doing more than five hours of exercise.

The findings suggest that above a threshold of three hours, the more exercise you do, the more your heart is likely to adapt, and the more the exercise, the more pronounced the changes. "Going to the gym frequently increases the thickness of your heart muscle and the volume of your heart chambers, particularly the right ventricle. It's a completely normal, healthy response. It shouldn't be misdiagnosed as being heart disease," says O'Regan. These adaptations allow the heart to pump more blood, which helps to supply exercising muscles with the oxygen and nutrients they need. Changes to the heart's thickness and volume happen in tandem, and this distinguishes them from the changes seen in disease, which occur in isolation.

Today, doctors across the world use a standard of set values to see if the thickness and volume of a person's heart fall into the healthy or abnormal range. This helps to ensure consistency between different hospitals. According to O'Regan, the data that underpins these ranges comes from a relatively small study with people who were mainly sedentary. He says, "In this latest study, we looked at a much larger and broader group of people. We found that more people reported being active than had done in previous studies. Our recommendations reflect this growing participation in exercise.".....And this interesting research shows that even moderate physical activity is associated with changes in the heart's size and shape, which are visible on a cardiac MRI.