Friday, 22 November 2013

How Exercise Changes Fat and Muscle Cells

Exercise promotes health, reducing most people’s risks of developing diabetes and growing obese. But just how, at a cellular level, exercise performs this beneficial magic — what physiological steps are involved and in what order — remains mysterious to a surprising degree.

Several striking new studies, however, provide some clarity by showing that exercise seems able to drastically alter how genes operate.

Genes are, of course, not static. They turn on or off, depending on what biochemical signals they receive from elsewhere in the body. When they are turned on, genes express various proteins that, in turn, prompt a range of physiological actions in the body.

One powerful means of affecting gene activity involves a process called methylation, in which methyl groups, a cluster of carbon and hydrogen atoms, attach to the outside of a gene and make it easier or harder for that gene to receive and respond to messages from the body. In this way, the behavior of the gene is changed, but not the fundamental structure of the gene itself. Remarkably, these methylation patterns can be passed on to offspring – a phenomenon known as epigenetics.

What is particularly fascinating about the methylation process is that it seems to be driven largely by how you live your life. Many recent studies have found that diet, for instance, notably affects the methylation of genes, and scientists working in this area suspect that differing genetic methylation patterns resulting from differing diets may partly determine whether someone develops diabetes and other metabolic diseases.

But the role of physical activity in gene methylation has been poorly understood, even though exercise, like diet, greatly changes the body. So several groups of scientists recently set out to determine what working out does to the exterior of our genes.

The answer, their recently published results show, is plenty.

Of the new studies, perhaps the most tantalizing, conducted principally by researchers affiliated with the Lund University Diabetes Centre in Sweden and published last month in PLoS One, began by recruiting several dozen sedentary but generally healthy adult Swedish men and sucking out some of their fat cells. Using recently developed molecular techniques, the researchers mapped the existing methylation patterns on the DNA within those cells. They also measured the men’s body composition, aerobic capacity, waist circumference, blood pressure, cholesterol levels and similar markers of health and fitness.

Then they asked the men to start working out. Under the guidance of a trainer, the volunteers began attending hourlong spinning or aerobics classes approximately twice a week for six months. By the end of that time, the men had shed fat and inches around their waists, increased their endurance and improved their blood pressure and cholesterol profiles.

Less obviously, but perhaps even more consequentially, they also had altered the methylation pattern of many of the genes in their fat cells. In fact, more than 17,900 individual locations on 7,663 separate genes in the fat cells now displayed changed methylation patterns. In most cases, the genes had become more methylated, but some had fewer methyl groups attached. Both situations affect how those genes express proteins.

The genes showing the greatest change in methylation also tended to be those that had been previously identified as playing some role in fat storage and the risk for developing diabetes or obesity.

“Our data suggest that exercise may affect the risk for Type 2 diabetes and obesity by changing DNA methylation of those genes,” says Charlotte Ling, an associate professor at Lund University and senior author of the study.

Meanwhile, other studies have found that exercise has an equally profound effect on DNA methylation within human muscle cells, even after a single workout.

To reach that conclusion, scientists from the Karolinska Institute in Stockholm and other institutions took muscle biopsies from a group of sedentary men and women and mapped their muscle cells’ methylation patterns. They then had the volunteers ride stationary bicycles until they had burned about 400 calories. Some rode strenuously, others more easily.

Afterward, a second muscle biopsy showed that DNA methylation patterns in the muscle cells were already changing after that lone workout, with some genes gaining methyl groups and some losing them. Several of the genes most altered, as in the fat cell study, are known to produce proteins that affect the body’s metabolism, including the risk for diabetes and obesity.

Interestingly, the muscle cell methylation changes were far more pronounced among the volunteers who had ridden vigorously than in those who had pedaled more gently, even though their total energy output was the same.

The overarching implication of the study’s findings, says Juleen Zierath, a professor of integrative physiology at the Karolinska Institute and senior author of the study, is that DNA methylation changes are probably “one of the earliest adaptations to exercise” and drive the bodily changes that follow.

Of course, the intricacies of that bogglingly complex process have yet to be fully teased out. Scientists do not know, for instance, whether exercise-induced methylation changes linger if someone becomes sedentary, or if resistance training has similar effects on the behavior of genes. Nor is it known whether these changes might be passed on from one generation to the next. But already it is clear, Dr. Ling says, that these new findings “are additional proof of the robust effect exercise can have on the human body, even at the level of our DNA.”

For the original article please click link below:

http://well.blogs.nytimes.com/2013/07/31/how-exercise-changes-fat-and-muscle-cells/

Tuesday, 19 November 2013

How To Get Motivated to Exercise

How To Get Motivated to Exercise
It can be hard to exercise. Here are 5 tips to help you get off the couch and get fit.
By Linda Wasmer Andrews
WebMD Feature Reviewed by David Ludwig, MD, PhD

You know you should do it. And you know why: Exercising -- simply put, moving instead of sitting -- is critical for safeguarding your health and setting a good example for your kids. So why does it seem so hard to get yourself moving?

The truth is: You can. But knowing how and why to exercise isn’t enough.You need to develop the right mind-set to get and stay motivated.

"Change is hard!" says certified health behavior coach Shelly Hoefs, fitness supervisor at the Mutch Women’s Center for Health Enrichment in Sioux Falls, S.D. "When we try to start exercising, we think of all the excuses for not doing it and all the things that have gotten in the way before. Getting fit starts to seem overwhelming. And that makes it feel stressful. Before long, we don’t want to do it anymore."

Here are 5 steps to get you moving in the right direction -- and keep you going.

1. Find Personal Motivation to Exercise

What you need to get you up off the couch is a reason that's important to you. At first, that may be some external factor, says Cal Hanson, director of the Sanford Wellness Center in Sioux Falls, S.D. It could be a number on the scale that surprises you or your doctor's recommendation that you need to move more to stay healthy.

There are all kinds of benefits to getting fit. Which matters most to you? Something as simple as taking a brisk walk after dinner every night helps to:

control your weight
strengthen your bones
enhance your muscles
reduce your risk for heart disease, type 2 diabetes, and some types of cancer
Plus, by becoming active, you're being a good role model for your children.

These benefits may get you started, but they may not cut it when it comes to keeping you moving day after day, Hanson says. To keep up your motivation to exercise over time, you also need to find your internal motivators. Maybe taking a yoga class leaves you feeling more energized or less stressed. Maybe a run or walk every day helps you let go of stress. Hanson says these are the kind of rewards that are meaningful to you on a personal level and that can help keep you motivated.

2. Set Realistic Goals to Get Fit

CDC guidelines call for adults to do 2 1/2 hours of moderate-intensity aerobic exercise a week. That's a 30-minute walk 5 days a week. If you kick it up a notch -- jogging or running, for example – the benefits multiply. Though it's fine to provide for a gentle start, ultimately the more the better.

You can aim for these exercise guidelines, but don't try to meet them at the start. "People lose their motivation to exercise when they try to do too much too soon," says Hanson.

So instead of walking for 30 minutes a day right off the bat, start out doing 15 minutes a day, 2 or 3 days a week.

Set weekly goals, gradually adding more time and intensity. At the end of each week, take a look at how you did. If you reached your goal, celebrate! "And if you didn't reach your goal," Hanson says, "think about what went wrong and how you're going to respond differently next time."

3. Stop Thinking of It as Exercise -- Do Something You Enjoy

You don't have to go to the gym to get a good workout. It's all about moving more -- however you do it. For some people, going to the gym provides structure that helps them focus and a sense of accomplishment when they're done. For others, it's a chore -- one they wind up avoiding as often as they can.

What else can you do? Almost anything that gets you -- and your family -- moving:

Walk the dog, or walk a neighbor's dog. They'll be grateful for the help!
Have dance contests with the kids instead of watching TV.
Go to the park and play hide-and-seek.
Shoot hoops with the kids.
Walk or bike to the store instead of driving.
Get off the train a stop early and walk the rest of the way to your office.
Take the stairs rather than the elevator.
If you think about it, you're surrounded by opportunities to get more active. Find the ones that you get excited about. You're more likely to keep doing them if you're having fun.

4. Plan How to Fit Exercise Into a Hectic Schedule

For busy parents, a major obstacle to getting fit is lack of time. If you wait for time to open up, chances are you won't be able to squeeze in a walk or a dance class very often. To avoid getting sidetracked by the daily demands of life, try these tips:

"Sit down with your schedule and really carve out blocks of time," says psychologist Susan Bartell, PsyD, author of Dr. Susan's Fit and Fun Family Action Plan. Put it in your calendar like any other appointment.
Add physical activity to things you already do. For example, pedal a stationary bike while reading or watching TV. Or take a walk with a friend to catch up instead of calling each other on the phone.
Plan activities you can do with your kids, such as going for bike rides or skating. Not only will you find more time for fitness, you'll help inspire your kids to move more.
If you plan ahead for potholes on the road to fitness, you're more likely to stay on course, Bartell says. "When you think through solutions to problems in advance, you're less likely to give up when a pothole comes along."

5. Bounce Back From Setbacks

You’ve set a reasonable fitness goal. You’ve prepared for potential problems. Yet somehow you still didn’t make it to the gym today as you had planned. Don't let that be your downfall.

"For many people, this is a slippery slope," Hanson says. "It reminds them of times when they failed before, and they begin to think of themselves as exercise failures."

When this happens, it’s time for an attitude adjustment so you don’t completely lose your motivation to exercise. If you miss the gym on Monday, that doesn’t mean your whole week is shot, Hanson says. It simply means you need to hit the gym on Tuesday or take the dog for an extra-long walk tonight.

Knowing how to exercise isn’t just a matter of learning how to use your body to hold a yoga pose or swing a racquet. It also involves learning how to use your mind to propel yourself into action and stick with a fitness routine.

"Start thinking of yourself as someone who exercises," says Hoefs. "Eventually, that will become your identity."

For the original article please click the link below:

http://fit.webmd.com/jr/parents/article/parents-motivated-to-exercise?page=3

Sunday, 17 November 2013

How Exercise Impacts (Good) Brown Fat Cells & (Bad) White Fat Cells

Did you know that your body has two different kinds of fat? Learn how an active lifestyle can reduce or minimize the amount of "bad" white fat you have in your body.
In the old Westerns it was always easy to identify the bad guys because they always wore black. But, in the ensuring decades it has not been as easy to delineate the good from the bad. Bad guys don’t always wear black, and every once in a while one of them actually turns out to be a hero.

Recent research sponsored by the American Diabetes Association and the National Institutes of Health is actually proving incredible insight into a notorious “bad guy,” and forcing researchers to rethink how we view good and bad fat.

Body fat—the good and the bad

Did you know that your body has two kinds of fats? No, seriously. Just like the fat that you can consume in foods, your body is naturally comprised of both good and bad fats. The question that researchers have been asking for years, is how we can increase the amount of “good fat” while reducing “bad fat?”

Body fat or adipose tissue, as it’s known in biology, actually plays several vital roles within the body. In addition to insulating the body and cushioning internal organs, body fat serves as an energy store and secretes hormones such as leptin and estrogen just to name a few. Brown fat or brown adipose tissue is considered to be “good fat” and is common to humans, rodents and small mammals. It was once believed that brown fat only existed in infants but was recently discovered in adults.

Researchers believe that brown fat may hold weight loss secrets that would benefit overweight and obese individuals. In infants and adults, brown fat actually generates heat to warm the body when it is exposed to cold. To generate heat the brown fat, mainly located in the neck and upper chest, burns calories through a unique thermogenic processes that raises the basal metabolic rate (BMR).

Brown fat is very different from white adipose tissue or white fat that develops from a sedentary lifestyle combined with poor diet. A certain amount of white fat is beneficial and necessary for bodily functions but problems arise when too much accumulates within the body. Elevated levels of white fat especially abdominal fat are related to several disease including obesity, cardiovascular disease, diabetes, and metabolic syndrome just to name a few. And, unlike brown fat, white fat doesn’t burn calories.

Muscular Build

New research into exercise and fat offers hope

Two studies of mice and humans conducted by the Joslin Diabetes Center in Boston suggest that exercise can actually led to a browning of white fat.

The studies found that mice that ran on an exercise wheel for 11 days and men who undertook 12 weeks of training on an exercise bicycle underwent a browning of their subcutaneous white adipose tissue that appears to have led to profound changes in the way that fat behaved in the body.

The browned white fat behaved more like brown adipose tissue in that it was more metabolically and thermogenically active than white adipose tissue. Researchers were able to discover that this “new” fat affected other bodily tissues by transplanting the exercise-training fat into obese mice. The murine study suggests that the browned fat was associated with increased glucose uptake, improved body composition, decreased fat mass and increased insulin sensitivity.

“Our results showed that exercise doesn’t just have beneficial effects on muscles, it also affects fat, said Kristin Stanford, PhD, a postdoctoral fellow at Joslin Diabetes Center. “It’s clear that when fat gets trained, it becomes browner and more metabolically active. We think there are factors being released into the bloodstream from the healthier fat that are working on other tissues.”

While researchers were unable to perform a similar transplant in humans they believe that exercise plays an important role.

“We know that exercise is good for us,” says Laurie Goodyear, PhD, senior researcher on the study and associate professor at Harvard Medical School. “But what we’re showing here is that fat changes dramatically in response to exercise training. This is not the fat that’s around your middle, which is bad fat and can lead to diabetes and other insulin resistance conditions. It’s the fat that’s under the skin, the subcutaneous fat that adapts in a way that appears to be having important metabolic effects.

Based upon the studies conducted by the Joslin Diabetes Center, it’s probably a safe bet that other researchers will be conducting trials of their own to investigate the correlation between exercise and the browning of white fat. In the meanwhile there are some valuable takeaways from the data that has been published. First, if you aren’t exercising then you need to start. Second, if you regularly engage in physical activity then you are definitely headed in the right direction, so keep it up.

For the original article, please click below:
http://www.muscleandstrength.com/articles/exercise-brown-white-fat-cells

Saturday, 16 November 2013

Five Things You’re Getting Wrong About Weight and Weight Loss

If I’m thin then I’m healthy, right? Wrong. There are several misconceptions people have about weight, losing it and what’s healthy. Here’s the low-down on some myths we’re better off busting.
Kids have to lose weight to shed obesity: As children grow, they put on weight, but how much is normal, and how much is excessive and potentially a hazard to their health? In the latest study, published in the journal Lancet, researchers from the National Institute of Diabetes and Digestive and Kidney Diseases at the National Institutes of Health developed a mathematical model to differentiate between healthy weight gain and the extra pounds that contribute to obesity. The model takes advantage of more accurate assessments of how many calories heavier children take in, as well as how quickly and efficiently they burn off those calories, and the ratio of fat to muscle in their bodies. The resulting model shows some kids can outgrow their obesity around puberty even if they don’t lose weight. That’s because obesity is a measure of not just weight but the ratio of height to weight known as the body mass index (BMI), and as children grow, they transform fat into muscle, which can weigh as much, if not more than fat tissue. So kids with a high BMI that might suggest obesity may not actually be overweight.
Still, the researchers say that teaching children about portion control and balancing what they eat with  physical activity to burn off excess calories are important lessons to learn early.
You can’t be fat and still be fit: A person’s level of physical fitness, as well as his weight, matters for overall health. A study in 2012 showed that overweight and obese people were at no greater risk of developing or dying from heart disease or cancer compared to normal weight people, but only if they were as metabolically fit as their slimmer counterparts. When it comes to premature death, it’s less about how much fat a person carries, but what kind of fat. Visceral or belly fat, for example, is considered more metabolically harmful than fat that sits just under the surface of the skin. Visceral fat, which is embedded more deeply within muscles and organs like the liver, release agents that can disturb the body’s energy balance, shunting calories into fat. Lean people can have high levels of visceral fat in their tissues, while overweight individuals may be carrying more subcutaneous fat and therefore could even be metabolically fitter than those who are slimmer.
Most people who put on weight, however, don’t enjoy a fit status for long. Eventually, the excess weight can contribute to higher rates of high blood pressure, diabetes, and heart disease.
You can eat what you want and just exercise to lose weight: Cutting calories by adjusting what you eat is actually the most effective way to lose weight. Ideally, consuming fewer calories and exercising is a more efficient way of dropping pounds, but for most people, passing up the chips is easier than sweating it out on a treadmill for an hour. Downing 140 calories from a can of soda, for example, takes only a few minutes, but would take half an hour of moderately intense walking to burn off. “You can greatly undermine weight loss efforts and general health by not considering the quality of the foods you eat. It is important to consider calorie density and nutrient density of foods to maximize exercise performance and improve health status,” says Gayl Canfield, the director of nutrition at Pritikin Longevity Center.
Long bouts of low-intensity exercise are best for losing weight: Fitness experts are trying to de-bunk the myth that pounds melt off faster with low-intensity aerobic exercise than higher intensity workouts. “It’s true the body burns proportionally more fat calories than carbohydrate calories at a lower training intensity, however, should you increase your exercise intensity into the cardiovascular zone you will burn more overall calories,” says Scott Danberg, the director of fitness at Pritikin Longevity Center. Mixing in some short bouts of high-intensity exercise can translate into benefits on the scale.
Eating protein is the best way to feel full and keep calories in check: Lean protein is indeed a good way to get filled up, but fiber is even better, because it comes with fewer calories. To make sure you’re not feeling hungry but still getting all your nutrients, load your plate with fruit, vegetables beans and grains.
To read the original article please click below