Thursday, July 28, 2016

The Mind-Gut Connection: How the Hidden Conversation Within Our Bodies Impacts Our Mood, Our Choices, and Our Overall Health

 

     
Combining cutting-edge neuroscience with the latest discoveries on the human microbiome, a practical guide in the tradition of The Second Brain, and The Good Gut that conclusively demonstrates the inextricable, biological link between mind and the digestive system.
We have all experienced the connection between our mind and our gut—the decision we made because it “felt right”; the butterflies in our stomach before a big meeting; the anxious stomach rumbling we get when we’re stressed out. While the dialogue between the gut and the brain has been recognized by ancient healing traditions, including Ayurvedic and Chinese medicine, Western medicine has  by and large failed to appreciate the complexity of how the brain, gut, and more recently, the gut microbiota—the microorganisms that live inside our digestive tract—communicate with one another. In The Mind-Gut Connection, Dr. Emeran Mayer, professor of medicine and executive director of the UCLA Center for Neurobiology of Stress, offers a revolutionary and provocative look at this developing science, teaching us how to harness the power of the mind-gut connection to take charge of our health and listen to the innate wisdom of our bodies.

The Mind-Gut Connection describes:

∙ Why consuming a predominantly plant-based diet is key for gut and brain health
∙ The importance of early childhood in gut-brain development, and what parents can do to help their children  thrive

The role of excessive stress and anxiety in GI ailments and cognitive disorders
How to “listen to your gut” and pay attention to the signals your body is sending you
∙ and much more.

 
Look inside a copy
 
 

Bike Fit: Optimise your bike position for high performance and injury avoidance

 

     
This practical guide, written by a leading BIKE FIT expert, takes you step-by-step through the BIKE FIT process – to ensure you maximise your cycling potential.

Do you suffer from lower back pain after a long weekend ride? Do your shoes wear out on one side more than the other? Are you experiencing numbness in your hands, or knee pain?

Phil Burt, Head Physiotherapist at British Cycling and Team Sky Consultant Physiotherapist, has worked with hundreds of cyclists to help them solve these and many other classic cycling niggles. In this book he outlines his methods to help you analyse your position and get the best from your bike. The right BIKE FIT can mean the difference between a good ride and a bad one, but a professional fit can cost more than you paid for your bike. The information is all here. Let Phil Burt guide you through your own BIKE FIT, to ensure your bike and body work in harmony.

Packed with useful diagrams, step by step diagnostics and case studies, this is the must-read for any cyclist keen to get a performance advantage.

 
Source

A 30-Minute ‘Me’ Break Can Make You a Better Worker, Study Shows

 


               
Newswise — If there are crumbs on your desk from countless lunches spent responding to emails and attending to other job-related responsibilities, it may be time to clean up and take a step back.
New research suggests that detaching from work during a lunch break can boost energy and help you to better respond to the demands of the day.

That’s the message behind a new study that finds early-career doctors — and the rest of us — can be better at our jobs if we simply set aside as little as 30 minutes a day for some “me” time.
The alternative, the study finds, is a scenario in which the patient may suffer.

The study, conducted by University of Florida and University of Tennessee at Chattanooga researchers and published in Psychology, Health & Medicine Journal’s third issue in 2016, found that active recovery activities like exercising and volunteering can help employees recover quickly and respond better to their jobs’ demands.

Researchers focused on the work and rest patterns of 38 early-career physicians from a teaching hospital in the Southeast. Of the participants, 63.2 percent were male and the median age was 29. The typical physician can average an 80-hour work week, leaving little opportunity for leisure and sleep.
“Residents are a very unique population, the stressors that they engage with throughout the day are a lot more significant than those of the average American. Therefore, these moments of replenishment are that much more important,” said Nicole Cranley, the study’s lead researcher. Cranley did the research while a doctoral candidate in UF’s department of behavioral science and community health and is now a postdoctoral fellow at the University of North Carolina at Chapel Hill.

The study assessed the time early-career physicians spend at work versus the time they spent on sleep and leisure, their ability to detach from work during non-work hours and whether they engaged in active or passive recovery activities.

Physicians ranked activities they engaged in at home and at work for how draining or energy boosting they were.

The results showed that the time early-career physicians spent on work exceeded the time they spent on sleep and leisure activities combined — and although eating was the most highly ranked at-work activity, even lunch breaks were consumed by work.

“They grab things and go, or they are eating while they are in conference or listening to a lecture. There really isn’t that time when they are not doing something related to work,” Cranley said.
Researchers also found that the participants had trouble psychologically detaching from work and that they engaged in more passive forms of recovery in their non-work time. While passive recovery, like watching television, is not necessarily harmful, it also does not help to boost energy levels beyond the baseline like active recovery activities can.

These patterns of working without taking time to recover fully can lead to burnout.
“Burnout is a serious issue,” said Cranley, “It’s usually related to the fact that you’re not taking enough time for self-care or engaging in activities that help you gain back some of those resources.”
Higher levels of burnout, she said, lead to higher rates of poor-quality patient care.

“You can only effectively care for someone if you are in a good state of mind. You have to be in a good place to be able to give your all to someone else,” she said.

One way to replenish resources is engaging in active recovery activities outside of work, no matter how little time is available to engage in those activities.

“It doesn’t matter if you only have 45 minutes to go to the gym — you take those 45 minutes for yourself,” Cranley said.

She said the study’s findings provide the groundwork to improve physician self-care and medical education.

“It’s a very unique situation that residents are in because they are expected to have all of the answers, when oftentimes they don’t,” she said.

She said the goal of the research is to help medical schools and hospitals recognize the nature of the stressors that the early career physician population faces and equip them with skills to deal with stress and recognize signs of burnout in themselves.

 
“I think where we are missing the mark is in medical education — it is a culture issue and we need to reassure our health professionals that it’s okay to need self-care,” Cranley said. “Everybody’s valuable, everybody needs to take care of themselves sometimes. We can’t all be 100 percent all the time.”

Exercise ability in middle age may be one key to longer life

 

     
(Reuters Health) – Middle-aged men who have more endurance in exercise tests may end up living longer than their peers who struggle with physical activity, a Swedish study suggests.

Researchers gave about 650 men an exercise test in 1967 when they were 50 years old. They asked participants to push themselves to the limit and ranked results into three groups based on low, medium or high endurance.

Each bump up in the endurance rankings was associated with a 21 percent lower risk of death during 45 years of follow-up, after adjusting for factors like smoking, blood pressure and cholesterol levels.

“Low fitness in middle age was associated with increased risk for all-cause mortality for several decades,” lead study author Dr. Per Ladenvall of the University of Gothenburg in Sweden said by email.

To assess physical fitness in middle age, researchers used exercise tests and examined data on the maximum amount of oxygen participants’ bodies could use. Generally, people with higher fitness levels can use more oxygen than individuals who are out of shape.

Researchers started the study by looking at data on 792 men from a larger study designed to investigate risk factors for cardiovascular disease and mortality. Of those, only 656 were able to complete a maximum exercise test pushing themselves to the limit; the rest had a health condition that made this type of test unsafe.

 
More

 

ACSM, Walk with a Doc Program Announce Partnership

 

     
Newswise — INDIANAPOLIS— The American College of Sports Medicine (ACSM) announced a new partnership with the Walk with a Doc program today, forged to promote walking for better health. Walk with a Doc encourages healthy physical activity in people of all ages, because it can reverse the consequences of a sedentary lifestyle and improve the health and well-being of Americans.

ACSM is an international leader in promoting the benefits of exercise. “Walking is a safe, easy and effective way for all people to become healthier through physical activity,” said Jim Whitehead, ACSM’s EVP/CEO. “ACSM brings the expertise of 50,000 clinicians, researchers, educators and exercise professionals to this collaboration to team up with Walk with a Doc’s efforts to promote physical activity through walking.”

With close to 250 communities and thousands of doctors across the United States, Walk with a Doc sees the partnership with ACSM as a way to expand its impact as scores of additional communities stand to benefit from the collaboration. “With a doctor’s approval, walking is low impact and safe for people with orthopedic ailments, heart conditions and those who are more than 20 percent overweight,” said David Sabgir, MD, founder of Walk with a Doc. “Working with ACSM can help us meet our goals to help Americans become more active and meet national guidelines for physical activity.”

 
Walk with a Doc is following ACSM’s lead to answer the Surgeon General’s Call to Action on Walking and Walkable Communities, released in September 2015. The call to action recognizes the importance of physical activity for people of all ages and abilities and encourages Americans to be more physically active through walking and asks leaders to better support walking and walkability in their communities.

 Walk with a Doc will also be supporting ACSM’s signature program, Exercise is Medicine®, by promoting the EIM health care provider’s pledge to encourage patients to participate in regular physical activity to support their health.

New Treatment for Low Back Pain: Minimally Invasive Procedure Receives FDA Clearance

 

     
Newswise — It’s the most common reason people go to their doctors – back pain. According to the National Institutes of Health, 80 percent of adults will experience low back pain some time in their lives. In fact, chronic low back pain, lasting 12 weeks or longer, affects nearly one-third of the nation’s population.

Laura Donlon, 48, of Monroe had been dealing with low back pain for five years before she found out about a back pain study at Beaumont Hospital in Royal Oak, Michigan. The flight attendant says her pain was unbearable at times, especially when sitting. Seeking relief from her pain, caused by a degenerative disc, she contacted the orthopedic research team at Beaumont for details.

Treatments for low back pain range from noninvasive to invasive: physical therapy, pain medications to major surgery, such as spinal fusion. Now a minimally invasive, nerve ablating procedure, recently cleared by the Food and Drug Administration, may give some people with chronic low back pain a new treatment option.

“In 25 years of practicing orthopedics, this is the most important clinical study I’ve ever done,” said Jeffrey Fischgrund, chairman, Orthopedics, Beaumont Hospital, Royal Oak and principal investigator of the FDA-approved Relievant SMART trial. “The system is proven to be safe and effective in clinical trials. It is much less invasive than typical surgical procedures to treat low back pain.”
A spine expert and orthopedic surgeon, Dr. Fischgrund helped design the research study. Research teams in the United States and Germany recruited 225 participants, with 150 receiving the minimally invasive, ablation treatment and 75 receiving the placebo.

Donlon was told she met the trial criteria and enrolled in the study. In December 2014, she had an outpatient spine procedure by Beaumont physicians. Because she did not know if she received the minimally invasive trial procedure or a placebo, she had to guess based upon results.
“After the procedure, I went home and within 24 hours I could touch my toes,” said Donlon, a running enthusiast and marathon competitor. “That’s when I figured I had the study procedure. Within 48 hours, I was back to work.” One year later, the research team confirmed what she suspected; she had undergone the nerve ablation treatment.

The treatment uses radio frequency energy to disable the targeted-nerve responsible for low back pain. Under local anesthesia with mild sedation, through a small opening in the patient’s back, an access tube is inserted into a specific bony structure of the spine, called a vertebral body. Radio frequency energy is transmitted through the device, creating heat, which disables the nerve. The access tube is then removed. The minimally invasive, implant-free procedure takes less than one hour.

“This is a new way to treat back pain. This type of treatment has never been done before,” said Dr. Fischgrund. “It’s revolutionary, compared to more traditional therapies; the odds of success are much greater.”

Patients eligible for this new procedure typically are candidates for more invasive back surgery or take strong pain medications, like opioids. Those research participants that had the radio frequency ablation procedure noticed significant improvement in their back pain within two weeks of surgery.
The nerve ablation procedure and technology was developed by Relievant Medsystems Inc., a California-based medical device company.

Nineteen months after Donlon’s minimally invasive nerve ablation treatment, she said, “Today, I have no back issues. I’m pain free. In fact, since my procedure, the pain has not recurred. I’m extremely grateful for the care and treatment I’ve received through my participation in the lower back pain study.”

 
For more information on this procedure and to be notified when it is available at Beaumont Hospital, Royal Oak, visit: http://www.beaumont.org/health-wellness/news/new-back-pain-treatment-receives-fda-approval

Friday, July 22, 2016

BMJ: Exercise as effective as surgery for middle aged patients with knee damage

 

     
Exercise therapy is as effective as surgery for middle aged patients with a common type of knee injury known as meniscal tear (damage to the rubbery discs that cushion the knee joint), finds a study in The BMJ this week.

The researchers suggest that supervised exercise therapy should be considered as a treatment option for middle aged patients with this type of knee damage.

Every year, an estimated two million people worldwide undergo knee arthroscopy (keyhole surgery to relieve pain and improve movement) at a cost of several billion US dollars. Yet current evidence suggests that arthroscopic knee surgery offers little benefit for most patients.

So researchers based in Denmark and Norway carried out a randomised controlled trial to compare exercise therapy alone with arthroscopic surgery alone in middle aged patients with degenerative meniscal tears.

A randomised controlled trial is one of the best ways for determining whether an intervention actually has the desired effect.

They identified 140 adults (average age 50 years) with degenerative meniscal tears, verified by MRI scan, at two public hospitals and two physiotherapy clinics in Norway. Almost all (96%) participants had no definitive x-ray evidence of osteoarthritis.

Half of the patients received a supervised exercise programme over 12 weeks (2-3 sessions each week) and half received arthroscopic surgery followed by simple daily exercises to perform at home.
Thigh muscle strength was assessed at three months and patient reported knee function was recorded at two years.

No clinically relevant difference was found between the two groups for outcomes such as pain, function in sport and recreation, and knee related quality of life. At three months, muscle strength had improved in the exercise group.

No serious adverse events occurred in either group during the two-year follow-up. Thirteen (19%) of participants in the exercise group crossed over to surgery during the follow-up period, with no additional benefit.

“Supervised exercise therapy showed positive effects over surgery in improving thigh muscle strength, at least in the short term,” say the authors. “Our results should encourage clinicians and middle aged patients with degenerative meniscal tear and no radiographic evidence of osteoarthritis to consider supervised structured exercise therapy as a treatment option.”
How did this situation – widespread practice without supporting evidence of even moderate quality – come about, ask two experts in a linked editorial? “Essentially, good evidence has been widely ignored,” say Teppo Järvinen at the University of Helsinki and Gordon Guyatt at McMaster University in Canada.

“In a world of increasing awareness of constrained resources and epidemic medical waste, what we should not do is allow the orthopaedic community, hospital administrators, healthcare providers, and funders to ignore the results of rigorous trials and continue widespread use of procedures for which there has never been compelling evidence,” they conclude.

 
Source

Brains of university athletes with history of concussion exhibit physical changes months, and even years, after the injury, new study finds

 

            
        
University athletes with a history of concussion had changes in the size, blood flow and connections in their brains months and even years after the injury – changes not seen in athletes without prior concussions, a new study has found.
The study looked at male and female varsity athletes in seven different contact and non-contact sports, demonstrating the relevance of the findings for the overall sporting community, not just traditional high risk sports such as hockey and football.

In the study published today in the Journal of Neurotrauma, researchers from St. Michael’s Hospital used advanced Magnetic Resonance Imaging (MRI) to comprehensively describe abnormalities in brain structure and function in 43 varsity athletes at the start of their sports seasons – 21 male, 22 female, 21 with a history of concussion and 22 without.

They found the athletes with a history of concussions had:
  • Brain shrinkage in the frontal lobes, the part of the brain involved in such things as decision-making, problem solving, impulse control and the ability to speak fluently, although nowhere near to the extent of that experienced by people with Alzheimer’s disease. The brains of athletes with prior concussions showed a 10 to 20-per-cent reduction in volume compared to those with no concussions.
  • Less blood flow (25 to 35 per cent) to certain areas of the brain, mainly the frontal lobes, which are very vulnerable to injury because of their location at the front of the brain. Reduced blood flow is associated with a longer recovery
  • A greater number of concussions was associated with reduced brain volume and blood flow
  • Changes in the structure of the brain’s white matter, the fibre tracts that connect different parts of the brain
“Sport concussion is still considered to be a short-term injury, but this study provides further evidence of brain changes that may lead to long-term health consequences, including the risk of re-injury, depression and cognitive impairments,” said Nathan Churchill, the study’s lead author and a post-doctoral fellow in St. Michael’s Neuroscience Research Program.
  “We expect to see changes in the brain right after an acute injury, but in this study we saw physical differences in brains of athletes that were scanned months to years after their last concussion.”
Behaviours controlled by the frontal lobe such as impulse control and problem-solving are often impaired in older athletes with a history of repeated head injury. These findings suggest that this area of the brain may be affected even for young, healthy adults with few concussions.

“We want to emphasize that, in general, the health benefits of sport participation still outweigh the risk of concussion,” said Dr. Tom Schweizer, head of the Neuroscience Research Program and a co-author of the paper. “Our findings can help to guide concussion management, and to minimize any future risk to athletes. The more we know about concussion, the better we can reduce these risks.”
This study received funding from Siemens Canada Ltd.

 
Source

 

Tuesday, July 19, 2016

How to increase the fat burned during exercise

 

     
When we exercise, our body’s oxidation of fat and carbohydrates depends on the intensity and duration of the activity. A new study analyses the effect of consuming an alkaloid, p-synephrine, on the burning of lipids and refutes the value of “miracle” diets: it is not possible to lose more than a kilogramme of fat per month.

New research published in the ‘British Journal of Clinical Pharmacology’ analyses p-synephrine’s role in burning fat during rest and exercise. This alkaloid can be found in nature (although at low concentrations) in a wide variety of citrus fruits such as oranges, mandarins and grapefruits, and commercially (at greater concentrations) as extract of bitter orange (Citrus aurantium).

“There is very little scientific information on this substance’s effects on metabolism and the oxidation of energy substrates during exercise or on the side effects of the continued consumption of this substance,” SINC was told by Juan Del Coso, a researcher from Camilo José Cela University and a lead author of the paper.
Because of its chemical similarity to ephedrine (a nervous system stimulant), and the substance’s activation of β3 adrenergic receptors, it has become a popular food supplement, typically included in weight loss products.

“The advantage of p-synephrine is its reduced activation of β1 y β2 receptors and consequent weak influence in raising arterial tension and heart rate, which mean the substance has fewer side effects than other adrenaline stimulators,” Del Coso adds.

The purpose of the investigation was to determine the effects of acute intake of 3 mg p-synephrine per kg body mass on energy metabolism and the rate of fat and carbohydrate oxidation during rest and exercise.

In a randomised, placebo-controlled, double-blind, experimental study, 18 subjects underwent two experimental trials: after consuming p-synephrine (3 mg/kg) and after taking a placebo (control test).
An hour after ingesting the substance, energy expenditure and arterial tension were measured before and after physical activity, in this case using a static bike. Acute p-synephrine ingestion had no effect on energy expenditure, heart rate or arterial pressure.

“However, the substance produced a notable change in substrate utilisation during exercise: p-synephrine ingestion pre-exercise increased the rate of fat oxidation and reduced carbohydrate oxidation at low and moderate intensity,” the expert explains.

In fact, p-synephrine increased individuals’ maximum capacity to burn fat, although it did not change the intensity at which this was attained. This data suggests that p-synephrine supplements could be useful to increase fat oxidation by of 7 g per hour of exercise.
 
There is no such thing as a “miracle” diet

The maximum rate found for fat oxidation during exercise, in this case in cyclists, was 0.7 g/min. That would suggest that in a best-case scenario, an individual could burn 42 g of fat after an hour of exercise at that level of intensity.

“This means the weight changes we experience when we start exercising are not based on fat loss, but mainly on fluid loss. This is why the majority of ‘miracle’ diets and slimming programmes produce a ‘rebound’ effect due to the recovery of the lost fluid,” the researcher argues.

Real weight change, based on the oxidation of fat through exercise (and diet) causes a real loss of 200–300 g per week, a little over 1 kg per month.

“That should be the aim: to lose a kilo per month, but a kilo of fat. It’s less attention-catching than miracle diet slogans, but scientifically speaking, effective change would be at that rate,” he points out. “That said, the rate of loss could increase with p-synephrine, but always combining the substance with exercise.”

The authors highlight the need for further study to determine the effects of the long-term use of this substance on energy production, metabolism at rest and substrate utilisation during exercise.
 
Source

Cranberry benefits may extend to the gut, heart, immune system and brain

 

                     
CARVER, Mass., July 19, 2016 – While decades of cranberry research has found that regular consumption of cranberry products promotes urinary tract health, leading scientists studying the bioactive components of fruits and other foods reported that cranberries possess whole body health benefits. In a July 2016 Advances in Nutrition supplement, Impact of Cranberries on Gut Microbiota and Cardiometabolic Health: Proceedings of the Cranberry Health Research Conference 2015, a team of international researchers reviewed the complex, synergistic actions of compounds that are uniquely cranberry. Their discussion led them to conclude that this berry may be more than just a tart and tangy fruit.

“It has been established that cranberries rank high among the berry fruits that are rich in health-promoting polyphenols,” notes lead author, Jeffrey Blumberg, PhD, of the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University in Boston, MA. “But now, recent investigations have shown that the cranberry polyphenols may interact with other bioactive compounds in cranberries that could protect the gut microbiota, and provide antioxidant and anti-inflammatory functions that benefit the cardiovascular system, metabolism and immune function.”

Recognition of the important role gut microorganisms play in human health has gained attention of scientists, reaching all the way up to the White House with the National Microbiome Initiative. Emerging evidence has found that the gut microbiome may impact the health of the immune system and brain, as well as how the body balances energy and uses carbohydrates and fat. Preliminary investigations with cranberries, some of which were performed in animal models, have revealed that cranberry bioactives show promise in helping to strengthen the gut defense system and protect against infection.

The effect of cranberry products on cardiovascular health and glucose management was also explained in the review. Authors of the paper described promising links between cranberry products and blood pressure, blood flow and blood lipids. One study identified a potential benefit for glucose management with low-calorie cranberry juice and unsweetened dried cranberries for people living with type 2 diabetes. Benefits for heart health and diabetes management have been attributed to the antioxidant and anti-inflammatory effects of the polyphenols in cranberries.

Given the wide range of ways to consume cranberries – juice, fresh, sauce, dried, or as an extract in beverages or supplements – additional human studies will help determine all the ways that cranberries may influence health. The scientific community and the cranberry industry agree – the impressive potential that cranberry bioactives may have on public health is worthy of further exploration.

“The bioactives in cranberry juice, dried cranberries and a variety of other cranberry sources have been shown to promote an array of beneficial health effects,” explains Dr. Blumberg. “Given the complex nature and diversity of compounds found in berry fruits and how they interact with each other, I believe we have only scratched the surface when it comes to identifying the potential power of the cranberry.”
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To read the proceedings in their entirety, the Advances in Nutrition supplement can be accessed here: Impact of Cranberries on Gut Microbiota and Cardiometabolic Health: Proceedings of the Cranberry Health Research Conference 2015.
The Cranberry Health Research Conference was sponsored by the Cranberry Institute, with grant support provided by the Cranberry Marketing Committee (CMC), an instrumentality of the United States Department of Agriculture, Agriculture Marketing Service (USDA/AMS), that administers the Cranberry Marketing Order, 7 Code of Federal Regulations 929, as authorized under the Agricultural Marketing Agreement Act of 1937, as amended, and the American Cranberry Growers Association.

 
For more information about the Cranberry Institute, along with the health benefits of cranberries and current scientific research, visit: http://www.CranberryInstitute.org.

Want to Cut Calories? New Studies Suggest Placing Orders Before It’s Time to Eat

 

     
Newswise — PHILADELPHIA – Want to cut calories and make healthier meal choices? Try avoiding unhealthy impulse purchases by ordering meals at least an hour before eating. New findings from researchers at the Perelman School of Medicine at the University of Pennsylvania and Carnegie Mellon University show that people choose higher-calorie meals when ordering immediately before eating, and lower-calorie meals when orders are placed an hour or more in advance. The results, which have implications for addressing the nation’s obesity epidemic, are published in the Journal of Marketing Research.

“Our results show that ordering meals when you’re already hungry and ready to eat leads to an overall increase in the number of calories ordered, and suggest that by ordering meals in advance, the likelihood of making indulgent purchases is drastically reduced,” said lead author Eric M. VanEpps, PhD, a postdoctoral researcher at the Penn Center for Health Incentives and Behavioral Economics, who conducted the studies while a graduate student at Carnegie Mellon. “The implication is that restaurants and other food providers can generate health benefits for their customers by offering the opportunity to place advance orders.”
Researchers conducted two field studies examining online lunch orders of 690 employees using an onsite corporate cafeteria, and a third study with 195 university students selecting among catered lunch options. Across all three studies, the researchers noted that meals with higher calorie content were ordered and consumed when there were shorter (or no) waiting periods between ordering and eating.

The first study was a secondary data analysis of over 1,000 orders that could be placed any time after 7 a.m. to be picked up between 11 a.m. and 2 p.m. The second study randomly assigned participants to place orders before 10 a.m. or after 11 a.m. The third study randomly assigned university students to order lunch before or after class, with lunches provided immediately after class.

In the first study, VanEpps and colleagues from Carnegie Mellon University found that for every hour of delay between when the order was placed and the food was ready (average delay of 105 minutes), there was a decrease of approximately 38 calories in the items ordered. In the second study, the researchers found that those who placed orders in advance, with an average delay of 168 minutes, had an average reduction of 30 calories (568 vs. 598) compared to those who ordered closer to lunchtime (with an average delay of 42 minutes between ordering and eating). The third study showed that students who placed orders in advance ordered significantly fewer calories (an average of 890 calories) compared to those who ordered at lunchtime (an average of 999 calories).
  In all three studies, lower caloric totals were generally not confined to any specific population subsets. Failure to eat breakfast did not emerge as a factor in the observed effect of time delay on total lunch calories, nor were there any observed differences in meal satisfaction between meals ordered in advance and those ordered for immediate consumption.

“These findings provide one more piece of evidence that decisions made in the heat of the moment are not as far-sighted as those made in advance,” said George Loewenstein, PhD, the Herbert A. Simon University Professor of Economics and Psychology at Carnegie Mellon, and senior author on the study. “For example, people who plan to practice safe sex often fail to do so when caught up in the act, and people who, in dispassionate moments, recognize the stupidity of road rage nevertheless regularly succumb to it. Unfortunately, pre-commitment strategies are more feasible when it comes to diet than to many other ‘hot’ behaviors.”

Based on findings from other studies, VanEpps says there is a potential concern that people who cut calories in one meal might “make up” for the calorie reductions later, whether at dinner or via snacking, though there is little evidence that participants in these studies were aware that lunches ordered in advance had fewer calories. The authors suggest future research in the form of longitudinal studies that measure eating decisions over a longer period of time would be useful in addressing this issue. In addition, because the two employee workplace studies provided discounted food and the university-based study provided free food, future research examining analogous situations where participants pay full price for their meals would be beneficial.

Funding for the study was provided by Loewenstein’s personal research funds.
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Penn Medicine is one of the world’s leading academic medical centers, dedicated to the related missions of medical education, biomedical research, and excellence in patient care. Penn Medicine consists of the Raymond and Ruth Perelman School of Medicine at the University of Pennsylvania(founded in 1765 as the nation’s first medical school) and the University of Pennsylvania Health System, which together form a $5.3 billion enterprise.

Wednesday, July 13, 2016

Lighter Weights Just as Effective as Heavier Weights to Gain Muscle, Build Strength: McMaster Research

 

     
Newswise — New research from McMaster University is challenging traditional workout wisdom, suggesting that lifting lighter weights many times is as efficient as lifting heavy weights for fewer repetitions.

It is the latest in a series of studies that started in 2010, contradicting the decades-old message that the best way to build muscle is to lift heavy weights.

“Fatigue is the great equalizer here,” says Stuart Phillips, senior author on the study and professor in the Department of Kinesiology. “Lift to the point of exhaustion and it doesn’t matter whether the weights are heavy or light.”

Researchers recruited two groups of men for the study—all of them experienced weight lifters—who followed a 12-week, whole-body protocol. One group lifted lighter weights (up to 50 per cent of maximum strength) for sets ranging from 20 to 25 repetitions. The other group lifted heavier weights (up to 90 per cent of maximum strength) for eight to 12 repetitions. Both groups lifted to the point of failure.

Researchers analyzed muscle and blood samples and found gains in muscle mass and muscle fibre size, a key measure of strength, were virtually identical.

“At the point of fatigue, both groups would have been trying to maximally activate their muscle fibres to generate force,” says Phillips, who conducted the work with graduate students and co-authors Rob Morton and Sara Oikawa.

While researchers stress that elite athletes are unlikely to adopt this training regime, it is an effective way to get stronger, put on muscle and generally improve health.

“For the ‘mere mortal’ who wants to get stronger, we’ve shown that you can take a break from lifting heavy weights and not compromise any gains,” says Phillips. “It’s also a new choice which could appeal to the masses and get people to take up something they should be doing for their health.”
Another key finding was that none of the strength or muscle growth were related to testosterone or growth hormone, which many believe are responsible for such gains.

“It’s a complete falsehood that the short-lived rise in testosterone or growth hormone is a driver of muscle growth,” says Morton. “It’s just time to end that kind of thinking.”

Researchers suggest, however, that more work remains to be done in this area, including what underlying mechanisms are at work and in what populations does this sort of program work.
The findings are published online in the Journal of Applied Physiology.

 
A full copy of the study can be found at http://jap.physiology.org/content/jap/121/1/129.full.pdf

Wednesday, July 6, 2016

Why do aged muscles heal slowly?

 



Baltimore, MD– As we age, the function and regenerative abilities of skeletal muscles deteriorate, which means it is difficult for the elderly to recover from injury or surgery. New work from Carnegie’s Michelle Rozo, Liangji Li, and Chen-Ming Fan demonstrates that a protein called b1-integrin is crucial for muscle regeneration. Their findings, published by Nature Medicine, provide a promising target for therapeutic intervention to combat muscle aging or disease.

Muscle stem cells are the primary source of muscle regeneration after injury. These specialized adult stem cells lie dormant in the muscle tissue–off to the side of the individual muscle fibers, which is why they were originally dubbed satellite cells. When muscle fibers are damaged, they activate and proliferate. Most of the new cells go on to make new muscle fibers and restore muscle function. Some return to dormancy, which allows the muscle to keep repairing itself over and over again.

Rozo, the lead author, determined that the function of integrins (or, more specifically, the protein called β1-integrin) is absolutely crucial for maintaining the cycle of hibernation, activation, proliferation, and then return to hibernation, in muscle stem cells. Integrins are proteins that ‘integrate’ the outside to the inside of the cell, providing a connection to the immediate external environment, and without them, almost every stage of the regenerative process is disrupted.
The team theorized that defects in β1-integrin likely contribute to phenomena like aging, which is associated with reduced muscle stem cell function and decreased quantities of muscle stem cells. This means that healing after injury or surgery is very slow, which can cause a long period of immobility and an accompanying loss of muscle mass.

“Inefficient muscular healing in the elderly is a significant clinical problem and therapeutic approaches are much needed, especially given the aging population-and I am including myself in this population,” Fan explained. “Finding a way to target muscle stem cells could greatly improve muscle renewal in older individuals.”

Rozo and Li determined that the function of β1-integrin is diminished in aged muscle stem cells. Furthermore, when they artificially activated integrin in mice with aged muscles, their regenerative abilities were restored to youthful levels. Importantly, improvement in regeneration, strength, and function were also seen when this treatment was applied to animals with muscular dystrophy, underscoring its potential importance for the treatment of muscle disorders.

Muscle stem cells use b1-integrin to interact with many other proteins in the muscle external environment. Among these many proteins, they found a clue that one called fibronectin might be most relevant. To connect b1-integrin to fibronectin, they teamed up with another group led by scientists from the Nestlé Institute of Health Sciences, in addition to researchers from the EPFL EDBB Doctoral Program, the Leibniz Institute for Age Research, the Ottawa Hospital Research Institute, and the Max Planck Institute of Biochemistry.

They discovered that aged muscles contain substantially reduced levels of fibronectin compared to young muscles. Like b1-integrin, eliminating fibronectin from young muscles makes them appear as if they were old, and restoring fibronectin to aged muscle tissue restores muscle regeneration to youthful levels. Their joint efforts demonstrated a strong link between b1-integrin, fibronectin and muscle stem cell regeneration, which is the subject of a second paper, also published by Nature Medicine in the same issue.

“Taken together, our results show that aged muscle stem cells with compromised b1-integrin activity and aged muscles with insufficient amount of fibronectin both root causes of muscle aging. This makes b1-integrin and fibronectin very promising therapeutic targets,” Fan said.
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