Thursday, October 30, 2014

Body Composition and Bone Density Trends in Distance Runners

by
http://breakingmuscle.com  

Most runners know they need to develop strength in order to excel at running and reduce the risk of injuries. But size can sometimes come with strength, which can reduce running performance if taken too far.

In a recent Journal of Strength and Conditioning Research paper, investigators examined the role of muscle size in running performance and injury prevention.

What the research says:
  • Bone health was significantly improved in subjects with more lean muscle.
  • Researchers recommended resistance training and plyometrics for runners.




Background

Endurance sports have a high degree of repetitive action that can wear on the joints and bones of the athletes. Running in particular is well known for this effect, due to the constant impact with the ground.

The flip side of this phenomenon is that the impact associated with running also improves bone density. The Journal study was interested in the interplay between muscle size, bone quality, and body composition in distance runners.

Study Design

36 Division I male and female cross country runners were examined for this study. Their stress fracture histories were taken, and their best performances were measured after the season was over. These values were compared to several measures taken in the lab. Bone density and composition were analyzed, as well as total lean mass, muscle size in the leg, and fat mass.

Results

The researchers discovered numerous physical correlations that we would expect. For example, more bodyweight corresponded with more lean muscle mass, and lean mass was positively correlated with improvements in bone mineral density and composition in both men and women. However, the number of correlations that yielded improvements in performance were few.


The researchers also noted the difference between genders. In the women, none of the studied variables correlated to performance. For the male runners, there were a few interesting relations between the data. Higher fat mass was positively correlated with performance in 10k races, and a higher percentage of body fat correlated to better performance in 5k races. More body fat wasn’t correlated with higher bodyweight in this study.

Recommendations

The results showed that bone health was significantly improved by larger and stronger muscles. Further, it takes physical preparation to achieve the level of the participants in the study, which is benefited by strength training. To that end, the researchers of this study recommended resistance training and plyometrics for runners.

Tuesday, October 28, 2014

Monday, October 27, 2014

Birth season affects your mood in later life

 New research shows that the season you are born has a significant impact on your risk of developing mood disorders. People born at certain times of year may have a greater chance of developing certain types of affective temperaments, which in turn can lead to mood disorders (affective disorders). This work is being presented at the European College of CNP Congress in Berlin.


The group found the following statistically significant trends:
· cyclothymic temperament (characterized by rapid, frequent swings between sad and cheerful moods), is significantly higher in those born in the summer, in comparison with those born in the winter.
· Hyperthymic temperament -- a tendency to be excessively positive -- were significantly higher in those born in spring and summer.
· Those born in the winter were significantly less prone to irritable temperament than those born at other times of the year.
· Those born in autumn show a significantly lower tendency to depressive temperament than those born in winter.

READ MORE
http://www.sciencedaily.com 1.htm

Saturday, October 25, 2014

Form Burger Patties as Gently as Possible for a More Satisfying Crust

by Melanie Pinola
 http://lifehacker.com


By "as gently as possible," America's Test Kitchen means packing the ground meat as if you're "cradling a newborn baby."
They explain on NPR:
Every time you touch, grind, move, look at ground meat, it starts to release a protein that's really, really sticky called myosin. ... Basically, when you grind beef, you're damaging the meat fibers — so the more you damage it or touch it or pack it, the more of that sticky protein is going to be formed. And the sticky protein sometimes might not be a bad thing — for instance, [for] something like meatloaf, where you want a bit more cohesion. But for a burger, where you're going to bite into it, you want it to almost just hang together. ...
We kind of bundle the meat into mounds and then very gently pack the meat into patties. By "pack," I really mean it's ... hands-off — it's like you're cradling a newborn baby, almost. You have to be very, very gentle with it. The best part of that is the surface of the burger itself is not completely smooth — it's got all these crags and crevices in it. So when you go to cook it, you're going to have a really nice crust that forms on the sides of the beef.
If you're going to go through all the trouble of grinding your own meat, as you should, follow through with gentle handling to keep the burger tender but crusty on the outside.

Friday, October 24, 2014

Is Your Supermarket Sabotaging Your Diet?

from  http://blog.fooducate.com  

America has become an obesogneic country. That’s because everywhere you turn to, unhealthy food and beverage are within arms reach. Supermarkets have become part of the problem.
In a recent study conducted by the University of Massachusetts Medical School, 240 obese adults from the greater Boston area participated in a weight loss intervention that focused on increasing fiber intake. The participants were highly motivated, but motivation was not enough to succeed. The offerings at the local grocery store had a profound effect on the chances of success:
“…even among these highly motivated patients, those who had a shorter trip to the nearest grocery store with a good selection of healthy foods did better in boosting their consumption of fiber and fruits and vegetables than those who had to travel farther for healthy foods, the researchers found.” Read more…
Around 40% of the supermarkets in the vicinity of the dieters did not have an adequate proportion of healthy fare such as fresh fruits and vegetables, and whole grain foods. The researchers found a correlation between access to a “healthier” grocery store and success in the dietary intervention. Not surprising.
According to the Center for Science in the Public Interest (CSPI), supermarkets set us up for failure at the checkout counter. It is basically a booby-trap for healthy eaters because nothing at the checkout can be considered even close to healthful. End-caps, the items sold at the ends of the aisles, usually tend to be junk foods as well.
Does the supermarket close to your home have a good selection of fresh produce and healthy foods? Do you choose to drive farther in order to purchase healthier food?

Tuesday, October 21, 2014

Citrus Juice, Vitamin C Give Staying Power To Green Tea Antioxidants

from    http://www.sciencedaily.com


To get more out of your next cup of tea, just add juice.
A study found that citrus juices enable more of green tea's unique antioxidants to remain after simulated digestion, making the pairing even healthier than previously thought.
The study compared the effect of various beverage additives on catechins, naturally occurring antioxidants found in tea. Results suggest that complementing green tea with either citrus juices or vitamin C likely increases the amount of catechins available for the body to absorb.

"Although these results are preliminary, I think it's encouraging that a big part of the puzzle comes down to simple chemistry," said Mario Ferruzzi, assistant professor of food science at Purdue University and the study's lead author.
Catechins (pronounced KA'-teh-kins), display health-promoting qualities and may be responsible for some of green tea's reported health benefits, like reduced risk of cancer, heart attack and stroke. The problem, Ferruzzi said, is that catechins are relatively unstable in non-acidic environments, such as the intestines, and less than 20 percent of the total remains after digestion. 

"Off the bat you are eliminating a large majority of the catechins from plain green tea," Ferruzzi said. "We have to address this fact if we want to improve bodily absorption."  
Ferruzzi tested juices, creamers and other additives that are either commonly added to fresh-brewed tea or used to make ready-to-drink tea products by putting them through a model simulating gastric and small-intestinal digestion. Citrus juice increased recovered catechin levels by more than five times, the study found. Ascorbic acid, or vitamin C, used to increase shelf life in ready-to-drink products, increased recovered levels of the two most abundant catechins by sixfold and 13-fold, respectively.

The study, published this month in Molecular Nutrition and Food Research, also found that soy, dairy and rice milk appeared to have moderate stabilizing effects. But Ferruzzi said the result is misleading; a chemical interaction between milk proteins and tea catechins apparently helps shelter the complex from degradation, a force likely overcome by enzymes within a healthy human digestive system.
Lemons and tea go even better together than their popularity might suggest. Lemon juice caused 80 percent of tea's catechins to remain, the study found. Following lemon, in terms of stabilizing power, were orange, lime and grapefruit juices. Ferruzzi said both vitamin C and citrus juices must interact with catechins to prevent their degradation in the intestines, although data made it clear that citrus juices have stabilizing effects beyond what would be predicted solely based on their vitamin C content.

"If you want more out of your green tea, add some citrus juice to your cup after brewing or pick a ready-to-drink product formulated with ascorbic acid," Ferruzzi said.
Ready-to-drink green tea products should optimally contain 100-200 mg of catechins, but oftentimes do not have sufficient levels of tea extract since some people do not like green tea's flavor, Ferruzzi said.
Although this study only examined green tea, Ferruzzi said he suspects that some of the results also could apply to black tea, which is produced by fermenting green tea. Many prefer black tea's flavor, although it contains lower total levels of catechins.

Studies have shown catechins from the green tea plant, Camellia sinensis, are able to detoxify toxic chemicals, inhibit cancer cell activity and stimulate production of immune-strengthening enzymes. Finding methods to improve uptake of these catechins may, therefore, be important in improving health, part of the study's goal, Ferruzzi said.
Ferruzzi currently is conducting an in vivo study, or study on a live organism, to quantify the ability of juices and vitamin C to increase levels of catechins in the intestines and bloodstream of animals and, by extension, in humans. He collaborates with the NIH-funded Purdue Botanicals Research Center on this project.
"This next study is designed to get us past the limitations imposed by our digestive model, which is really just a simple screening process that relies on preset physiology parameters," he said. "Human digestion is a lot more complicated."
To see if juices and vitamin C actually increase catechin absorption, researchers will have to find out if increased levels of intestinal catechins translate to higher levels of absorbed catechins in live animals and humans. They also will need to better document effects upon catechin metabolism in order to prove, for instance, that increased levels of absorbed catechins are not leveled off by metabolic factors, Ferruzzi said.
"This study tells us a lot of interesting things, but it raises many questions that have yet to be answered," he said.
The study was funded by the National Institutes of Health.

Monday, October 20, 2014

More Magnesium

from http://www.healthyfellow.com

Many people aren’t getting enough magnesium (Mg) in their daily diets and through basic supplementation. Now, you might think you’re not one of those people. But, recent studies reveal that magnesium deficiency is surprisingly common. Sometimes it’s even present in otherwise healthy young adults and in those who take multivitamin/mineral supplements. What’s more, certain popular medications, including those used to treat gastric reflux or GERD often contribute to a lack of magnesium or hypomagnesemia.

When attempting to address sub-optimal magnesium levels, it’s vital to be aware of the richest food sources of this essential mineral. Simply put, unless you make it a point to seek out foods abundant in magnesium, you’ll likely fall short of the recommended daily value (DV) of 400 mg. To that end, I suggest you include more of the following items in your eating plan: almonds (20% DV/oz), black beans (30% DV/cup), cashews (19% DV/oz), chia seeds (23% DV/oz), flax seeds (21% DV/oz), pumpkin seeds (18% DV/oz), pure cocoa powder (35% DV/oz), Swiss chard (38% DV/cup), spinach (39% DV/cup) and sunflower seeds (23% DV/oz). Also of note, the legumes, nuts, seeds and vegetables mentioned above are all excellent sources of antioxidants, dietary fiber and numerous minerals and vitamins.

At one point or another, most of you have probably read about the countless health benefits associated with magnesium intake. But, it’s easy to forget why any given nutrient is essential for wellness. So, I want to highlight several recent publications that act as reminders about why we should strive to get enough Mg every single day. On the one hand, three current studies report that those who lack adequate magnesium are more likely candidates for bone fractures, heart disease and ischemic stroke. This points to the importance of addressing any latent deficiency. With respect to addressing deficiencies, four other trials report that normalizing magnesium levels via supplementation addresses multiple health risks such as excessive inflammation, high blood pressure, insulin resistance and poor physical capacity. In addition, supplementing with magnesium can, likewise, help with a broad range of chronic health conditions, including migraine headaches.
In closing, I want to address a question that is frequently posed to me. Which form of magnesium is best? There is no definitive answer. Generally speaking, I consider magnesium citrate an affordable, accessible and well-absorbed option. If cardiovascular health is a primary concern, I usually recommend magnesium taurate – a form of magnesium bound to taurine, an amino acid which may help regulate blood pressure and heart rhythm. Lately, there has also been a considerable amount of interest paid to a newly developed magnesium chelate known as magnesium threonate. This intriguing nutraceutical may support healthier age-related cognitive functioning. It’s expensive, but possibly worth the added cost for those in need. If you’re in good general health, no matter which form of magnesium you opt for, you should always strive to reach or surpass the 400 mg/day guideline. However, those with kidney disease or other serious medical conditions should always consult with their health care providers prior to supplementing with minerals such as magnesium and potassium.

A Simple Protocol for Testing Your Work Capacity

few years ago, I had an opportunity to develop a training program for a large joint-military unit (Army, Navy, Marines, and Air Force). Fortunately, the only requirement of the commanding officer was that I use functional fitness training concepts to prepare his troops for deployment.

Unfortunately, it was difficult to establish initial fitness baselines because each branch had it’s own individual physical training test. So, in order to simplify the process, I developed a test using minimal equipment that provides a set of objective data points.

Read More 

Saturday, October 18, 2014

Friday, October 17, 2014

Your Apples Are A Year Old

Written by
http://www.foodrenegade.com

The produce you buy in the supermarket or grocery store is not fresh. With many items, like spinach, the leaves may have been plucked no more than a few weeks ago. But with many others, like apples, the fruit probably sat in cold storage for a year before making its way to the supermarket.
I thought this was common knowledge.
But in a recent Facebook discussion in which many readers chimed in with incredulous statements like, “A year old? No way!” I realized I was wrong. This information is not common knowledge.
But it should be.
Here in the U.S. apples generally ripen between August and September. They pick the apples when they’re slightly unripe, treat them with a chemical called 1-methylcyclopropene, wax them, box them, stack them on pallets, and keep them in cold storage warehouses for an average of 9-12 months.
I guess we should be grateful. It used to be that rather than being sprayed with 1-methylcyclopropene (also known as 1-MCP), cold storage apples were sprayed with fungicide.
From the USDA’s Agricultural Research Service, we learn this:
Apples not intended for fresh market are stored at low temperatures, with low levels of oxygen and high levels of carbon dioxide. While this slows the apples’ natural production of ethylene and its effects, fungicides must often be applied to prevent fungal rots from taking hold. But since its commercial debut in 2002 under the name “SmartFresh,” 1-MCP has in some cases diminished the need for such treatment.
(source)
In fact, the development and use of 1-MCP has made it common for apples to sit even longer in cold storage. That’s because, according the USDA’s Agricultural Research Service,
On average, treated apples stayed firm for 3 to 6 months longer than untreated controls when placed in controlled-atmosphere storage conditions. Red Delicious apples, for example, stayed crunchier 2 to 3 weeks longer than untreated controls after removal from storage.
(source)

Just how long are apples stored before being sold?

After learning that apples that have sat in cold storage for 12 months are commonly called “birthday apples” within the industry, one Australian investigative news organization decided to do a test to see just how old the apples on their grocery store shelves really were. They collected samples from major Australian supermarkets and sent them to the Sydney Postharvest Laboratory for testing.
The results?
Analysis showed the Woolworths samples were about 10 months old while the Norton Street and Coles products had spent 9 months in storage since being harvested.
(source)

But what about in the U.S.?

According to Martin Lindstrom, author of Brandwashed: Tricks Companies Use to Manipulate Our Minds and Persuade Us to Buy, the average supermarket apple is 14 months old. This is unsurprising to me, but may be shocking to you.
That’s because my husband used to manage a cold-storage warehouse for Harry & David when we lived in Oregon. He saw first hand how their “fresh fruit” was handled — from harvest in the nearby valleys to specialized climate control storage.
What he saw inspired me to never want to eat a grocery store fruit again, long before I ever became the “Real Foodie” that I am today. I wish I could go into details, but honestly? I don’t want to be sued!

Should you care about the age of your produce?

If you want to eat apples all year long, regardless of the season, maybe you’re glad to hear that modern engineering and science have mastered the art of keeping apples “fresh” for a year or more.
Yet at what cost?
The obvious differences in flavor and texture between fresh apples and stored apples aside, what’s so bad about eating produce that’s this old?
Nutrients.
Aside from dietary fiber and sugar, apples are a rich source of polyphenols — antioxidants that can help fight cancer and improve post-workout recovery by reducing muscle fatigue.
Yet according to this study, antioxidant activity in apples gradually drops off after three months of storage in the cold. An apple stored for nearly a year? It will have almost no antioxidants remaining in it whatsoever.
This is also true of most vegetables and fruits: the less fresh they are, the less nutrients they have.

So, how do you get the most nutrients from your apples?

Buy fresh. Don’t assume you’ll get apples year round. Buy in season. Buy from a local farmer when possible. Once you buy your apples, store them on your counter top rather than the fridge.
Quickly eat or remove bruised apples as the old saying is most certainly true, “one bad apple spoils the bunch.”
Don’t assume that buying organic apples will automatically mean you’re buying fresh apples either. Although SmartFresh (1-MCP) is not currently approved for use on organic apples, organic growers still use approved non-synthetic fungicides and controlled atmosphere cold storage to achieve a similar effect.

Thursday, October 16, 2014

Ginseng for Colds and Flu

Two populations that are most vulnerable to the common cold and influenza are young children and the elderly. Fortunately, a special extract of North American ginseng is building a strong reputation as a safe and natural way to change that trend. It seems that the extract in question, known commercially as COLD-fX, contains high levels of a group of substances known as polysaccharides. These naturally occurring chemicals have been shown to support the body’s immune system by increasing the numbers and activity of natural killer cells, macrophages and t-lymphocytes – major players in various stages of the immune response. (1,2)
In March 2006, a study investigating the effects of COLD-fX on “acute respiratory illness” (ARI) appeared in the Journal of Alternative and Complementary Medicine. 43 healthy seniors were given a 200 mg capsule of N. American ginseng extract or a placebo twice a day for a total of 4 months. After one month of treatment, all the participants were also administered an influenza vaccine. The volunteers were asked to document their experiences for any signs of respiratory illness and take note of any adverse effects that might be due to either “medication”. Here’s what the study results revealed:
  • No adverse reactions were reported in the placebo and treatment volunteers.
  • During the first two months of the trial, both groups reported similar outcomes.
  • The second half of the study demonstrated a 48% reduction in ARIs in those using ginseng and a 55% decrease in ARI symptom duration.
The authors of the study concluded that, “Daily COLD-fX administration can thus be a safe, natural therapeutic means of prevention of ARI in healthy seniors”. (3)
A larger trial, presented in the journal Canadian Family Physician, examined the impact of N. American ginseng or a placebo on a total of 279 volunteers of all ages (18-65). The one common trait they possessed was having had at least 2 colds during the previous year. Approximately half of the group was given 200 mg of N. American ginseng twice daily. The remainder took an identical looking placebo. Once again, the duration of the trial was 4 months.
The results of this investigation clearly indicate that the ginseng users had a lower incidence of colds, fewer instances of multiple colds, less severe symptoms and fewer days where they exhibited any cold symptoms. As in the previous study, no side effects were noted. (4)
Ginseng’s effects may be even more profound when it’s pitted against influenza. Two trials published in the Journal of the American Geriatric Society point to an “89% relative risk reduction of acute respiratory infections” during influenza season. What’s encouraging about these studies is that they were shorter in length (8 and 12 weeks) and involved volunteers with an average age of over 80. This may indicate rapid immune boosting effects and a broad degree of safety, even in populations that may be more vulnerable to adverse reactions. (5)
There is a very real safety concern about giving young children any type of preventive medicine, natural or otherwise. Therefore, a toxicity experiment was conducted and appeared in the August 2008 issue of the journal Pediatrics. It studied the relative safety of COLD-fX in a group of 46 children (aged 3-12) who developed upper respiratory infections. No adverse effects were noted in the children given a low or moderate dose of the ginseng extract or the inert placebo. (6)


All of the above research was conducted on North American ginseng. But other varieties of this root, such as Korean red ginseng, may also promote a vital immune system. However, different kinds of ginseng may impact immunity differently. For instance, Korean red ginseng is theorized to keep the body’s defenses strong with a stress reducing effect. Ginseng has historically been known as an adaptogen, a substance that aids the body to adapt to physical and psychological stressors. Researchers in Matsuyama, Japan have recently determined that this stress adaptation can possibly support efforts to prevent the common cold and flu. (7)
Finally, I want to mention an Italian study from way back in 1996. It’s an example of ginseng being used as part of an integrative approach. 227 volunteers were given either a once daily ginseng supplement (Ginsana G – 100 mg) or a placebo for a total of 12 weeks. At the 4 week mark, they all were administered an influenza vaccine. Those receiving the ginseng were nearly three times less likely to catch a cold or flu in the subsequent 2 months, as compared to the placebo + vaccine group. Blood tests revealed that antibodies rose significantly more in the ginseng users, as did natural killer cell activity – two markers of enhanced immune function.(8)
The issue of whether or not to get the flu vaccine is shrouded in controversy. The decision needs to be carefully examined on a case by case basis. I personally choose not to have a yearly “flu shot”, but from here on out, I will strongly consider using ginseng during those times when my immune system may need some additional support.

Tuesday, October 14, 2014

Energy Drinks Lead to Insomnia in Athletes

by

 http://blog.fooducate.com 

 

We’ve written numerous times in the past about the potential dangers of energy drinks, especially as it relates to teens. The excessive amounts of caffeine consumed have led kids to suffer from caffeine poisoning. There have been several deaths in the US, and multiple emergency room admittances due to energy drink consumption.

A new study published in the Journal of Nutrition looked at the effect of energy drinks on athletes. It reveals that they too suffer from unwanted side effects of these drinks. Athletes were given energy drinks or placebos before a sporting event. Their performance during the event (speed, height of jump, etc…) was measured, as well as their subjective feeling about it.

While the athletes did perform slightly better, and felt it too, there was a problem. They suffered from insomnia, nervousness, and activeness in the hours following consumption. These are well documented side effects of caffeine over-consumption.
What’s wrong with coffee?

 

Monday, October 13, 2014

How Far Is Too Far For Kids to Run?

by Ian McMahan

 But as the rate of childhood obesity continues to rise and the general aerobic fitness of children and adolescents continues to fall, another trend has emerged: Many of the children that still play sports often do so in excess.  While a great deal of attention has been devoted to the demanding year-round format of competitive youth baseball and soccer,  an increasing number of young athletes are also training for and competing in long-distance endurance events.  These young athletes are doing more than kids’ “fun runs” and 5K’s—they’re running marathons and Olympic-distance triathlons. Notably, the Students Run Los Angeles marathon-training program had more than 16,000 young marathon finishers between 1987 and 2005.

Read More
http://www.theatlantic.com

Wednesday, October 8, 2014

Walking is the superfood of fitness, experts say

Reuters



NEW YORK (Reuters) - Walking may never become as trendy as CrossFit, as sexy as mud runs or as ego-boosting as Ironman races but for fitness experts who stress daily movement over workouts and an active lifestyle over weekends of warrior games, walking is a super star.
For author and scientist Katy Bowman, walking is a biological imperative like eating. In her book, “Move Your DNA: Restore Your Health Through Natural Movement," she suggests there are movement nutrients, just like dietary nutrients, that the body needs.
“Walking is a superfood. It’s the defining movement of a human,” said Bowman, a biomechanist based in Ventura, California. “It’s a lot easier to get movement than it is to get exercise.”
Researchers say emerging evidence suggests that combined physical activity and inactivity may be more important for chronic disease risk than physical activity alone.
“Actively sedentary is a new category of people who are fit for one hour but sitting around the rest of the day," Bowman said. “You can’t offset 10 hours of stillness with one hour of exercise.”
Last year researchers at the University of Texas School of Public Health asked 218 marathoners and half marathoners to report their training and sitting times. Median training time was 6.5 hours per week. Median total sitting time was eight to 10.75 hours per day, suggesting that recreational distance runners are simultaneously highly sedentary and highly active.
Leslie Sansone, creator of the “Walk at Home: Mix & Match Walk Blasters” DVD, said too many people believe that spending grueling hours at the gym is the only way to fitness.
“There’s this “Biggest Loser” idea out there that if you’re not throwing up and crying you’re not getting fit,” she said, referring to the popular television weight-loss show.
She added that a small study of non-obese men published in the journal Medicine & Science in Sports and Exercise by scientists at Indiana University suggests that three five-minute walks done throughout three hours of prolonged sitting reverses the harmful effects of prolonged sitting on arteries in the legs.

Three miles (5 kilometers) per hour is a good beginning, gradually working to 4 miles per hour, she said about walking.
Dr. Carol Ewing Garber, president of the American College of Sports Medicine (ACSM), notes that fitness-walking guidelines of 10,000 steps per day may be too much for many.
“About 7,500 steps may be more accurate,” she said, adding that current ACSM recommendations call for at least 150 minutes of activity each week.
  Garber, a professor of movement sciences at Columbia University in New York, said research suggests that even one bout of exercise causes beneficial physiological effects.
But she concedes that walking does not do everything. It is less beneficial for bones than running, and for strength, it is better to lift weights.
“Still,” she said, “If you’re going to pick one thing, research says it should be walking.”

Tuesday, October 7, 2014

Gut Bacteria Still Get Fed When Hosts Are Too Sick to Eat

by Ed Yong
http://phenomena.nationalgeographic.com


For bacteria, the mammalian gut is like Shangri-La. It’s warm and consistently so, sheltered from the environment, and regularly flooded with a nutritious soup. But what happens when this all-you-can-eat buffet stops serving? What happens to microbes if their host stops eating?
When animals from mice to flies become sick, they often lose their appetite and temporarily stop eating. This makes sense: it takes a lot of energy to find or capture food, and for the moment, that energy is better spent on fighting off disease. But these short-term fasts harm the beneficial microbes that live in our guts. As we starve, so do they. Their absence makes us less efficient at digesting our food and creates vacancies that more harmful microbes could exploit.
A team of scientists, led by Alexander Chervonsky from the University of Chicago, has now found that mice deal with this problem by manufacturing molecules that feed their gut microbes during bouts of infection.
The cells of their intestines glom a sugar called fucose onto fats and proteins, which the bacteria can yank off and eat. The sugar is an emergency currency, used to pay off microbial employees when the usual coffers are empty, to keep them from quitting the firm.
Joseph Pickard and other team members discovered these back-up payments by injecting mice with molecules like LPS, found on the outer coats of bacteria. When such molecules are swallowed, they cause few problems. But if they float around the bloodstream, they can trigger an intense immune response. That’s what the team saw: the injections were enough to sicken the mice. They lost their appetites, became sluggish, developed diarrhoea, and lost weight.
In response, their intestinal cells started attaching fucose to proteins and other molecules, using a gene called Fut2. They then released these modified substances into their guts. As a result, they recovered faster, and regained their lost weight. When the team did the same experiments with mice that lacked the Fut2 gene, the animals took an extra day to put as much weight back on as their normal peers.
The team found that fucose only triggered a speedier recovery if the rodents had a normal community of gut microbes. The team suspected that the microbes were eating the sugars directly, and they developed a way of watching this feeding frenzy in action. They infused the mice with bacteria that would give off a green glow whenever they activated genes for digesting fucose. When the rodents were injected with LPS and began releasing fucose, these reporter microbes started glowing.
So, it seems that if sick hosts aren’t ingesting food from the outside, they’re secreting food from within for their bacteria. Of course, the microbes behind the illness might also be able to sup on these sugars. But the  team also found that fucose switches off virulence genes in gut microbes, diminishing their ability to cause disease. It not only feeds beneficial bacteria, but defangs harmful ones.
Although these experiments were done in mice, Chervonsky believes that something similar happens in humans—or at least, in the majority of them. Around one in five people lacks the Fut2 gene, and they are more likely to develop an inflammatory bowel disorder called Crohn’s disease. Perhaps that’s because they’re not as good at keeping a happy rapport with their gut microbes, during times of stress.
 

Friday, October 3, 2014

The Woman Who Walked 10,000 Miles (No Exaggeration) in Three Years

A hundred years ago, when Robert Falcon Scott set out for Antarctica on his Terra Nova expedition, his two primary goals were scientific discovery and reaching the geographic South Pole. Arguably, though, Scott was really chasing what contemporary observers call a sufferfest. He set himself up for trouble: Scott brought Manchurian and Siberian ponies that quickly fell through the snow and ice; he planned, in part, for his crew to “man-haul,” meaning that the men would pull sleds full of gear, instead of relying on dogs. Even when Scott’s men faltered, they continued collecting specimens, including rocks. The expedition ended terribly; everybody who made the push to the pole died. Miserable, starving and frostbitten, one of Scott’s last four men killed himself by walking into a blizzard without even bothering to put on his boots.
In the taxonomy of travelers, the word “explorer” suggests a morally superior pioneer, a man or woman who braves the battle against nature to discover new terrain, expanding our species’ understanding of the world. “Adventurer,” by contrast, implies a self-indulgent adrenaline junkie, who scares loved ones by courting puerile risk. The former, obviously, is the far better title, but it’s tough to claim these days. The world is Google-mapped. Reaching the actual virgin territory of space or the deep ocean requires resources that few possess. In short, the noble fig leaf of terra incognita has fallen away and laid bare the peripatetic, outsize bravado of Scott’s kindred spirits. The resulting itineraries are pretty strange. We now have guys like Felix Baumgartner sky-diving from a balloon-borne capsule at 128,100 feet.
Baumgartner falls squarely — and for more than four minutes, breaking the speed of sound — into the adventurer camp. But then there’s Sarah Marquis, who perhaps should be seen as an explorer like Scott, born in the wrong age. She is 42 and Swiss, and has spent three of the past four years walking about 10,000 miles by herself, from Siberia through the Gobi Desert, China, Laos and Thailand, then taking a cargo boat to Brisbane, Australia, and walking across that continent. Along the way, like Scott, she has starved, she has frozen, she has (wo)man-hauled. She has pushed herself at great physical cost to places she wanted to love but ended up feeling, as Scott wrote of the South Pole in his journal: “Great God! This is an awful place.” Despite planning a ludicrous trip, and dying on it, Scott became beloved and, somewhat improbably, hugely respected. Marquis, meanwhile, can be confounding. “You tell people what you’re doing, and they say, ‘You’re crazy,’ ” Marquis told me. “It’s never: ‘Cool project, Sarah! Go for it.’ ” Perhaps this is because the territory Marquis explores is really internal — the nature of fear, the

Wednesday, October 1, 2014

The Last 48 Hours

  


Elite Sharpening: Top runners seek a balance on the day before a race.
 

Sarah CrouchSARAH CROUCH, a 1:13 half marathoner and Olympic marathon trials qualifier, underscores the importance of experimenting with what works for you. Crouch performs a shakeout run of about 75 percent of her normal easy-day mileage two days prior to race day and then a shorter run with 2 x 1-minute and 2 × 30-second surges the day before to help her feel sharp.
"I've tried many different approaches in the last two days [before a race]. Too little running and I feel stale, too much and I don't have that certain 'pop' in my legs, so I try to balance those two during the last two days."
Neely Spence GraceyNEELY SPENCE GRACEY, who boasts a 15:27 5K PR and has run 32:16 for 10,000m, likes to do a non-timed, easy shakeout run (about 8 miles) two days before the race to help mitigate the impact of travel. The day before a race, she runs about 50 percent of her usual daily mileage (4–6 miles) with some light strides. Her main priority in the final two days is to relax and let her training do the racing for her.
"The biggest thing I have learned as a runner is that going with the flow and being flexible is a key component to success. There are so many things we cannot control, so it's all about handling the chaos of travel and the stress of competition using the least amount of energy."
Nick ArciniagaNICK ARCINIAGA, seventh-place finisher at the 2014 Boston Marathon in 2:11:47, focuses on reducing pre-race nerves and trying to get his legs to feel "snappy" in the final days before a race.
Arciniaga does a short run (for him, about 8 miles) two days before to shake out the travel while loosening his legs, and an easy run with four to six strides the day before to stimulate the neuromuscular system.