Does running a marathon push the body further than it is meant to go?

http://www.nytimes.com/2009/10/27/health/27well.html

The conventional wisdom is that distance running leads to debilitating wear and tear, especially on the joints. But that hasn’t stopped runners from flocking to starting lines in record numbers.

Last year in the United States, 425,000 marathoners crossed the finish line, an increase of 20 percent from the beginning of the decade, Running USA says. Next week about 40,000 people will take part in the New York City Marathon. Injury rates have also climbed, with some studies reporting that 90 percent of those who train for the 26.2-mile race sustain injuries in the process.

But now a best-selling book has reframed the debate about the wisdom of distance running. In “Born to Run” (Knopf), Christopher McDougall, an avid runner who had been vexed by injuries, explores the world of the Tarahumara Indians of Mexico, a tribe known for running extraordinary distances in nothing but thin-soled sandals.

Mr. McDougall makes the case that running isn’t inherently risky. Instead, he argues that the commercialization of urban marathons encourages overzealous training, while the promotion of high-tech shoes has led to poor running form and a rash of injuries.

“The sense of distance running being crazy is something new to late-20th-century America,” Mr. McDougall told me. “It’s only recently that running has become associated with pain and injury.”

The scientific evidence supports the notion that humans evolved to be runners. In a 2007 paper in the journal Sports Medicine, Daniel E. Lieberman, a Harvard evolutionary biologist, and Dennis M. Bramble, a biologist at the University of Utah, wrote that several characteristics unique to humans suggested endurance running played an important role in our evolution.

Most mammals can sprint faster than humans — having four legs gives them the advantage. But when it comes to long distances, humans can outrun almost any animal. Because we cool by sweating rather than panting, we can stay cool at speeds and distances that would overheat other animals. On a hot day, the two scientists wrote, a human could even outrun a horse in a 26.2-mile marathon.

Why would evolution favor the distance runner? The prevailing theory is that endurance running allowed primitive humans to incorporate meat into their diet. They may have watched the sky for scavenging birds and then run long distances to reach a fresh kill and steal the meat from whatever animal was there first.

Other research suggests that before the development of slingshots or bows, early hunters engaged in persistence hunting, chasing an animal for hours until it overheated, making it easy to kill at close range. A 2006 report in the journal Current Anthropology documents persistence hunting among modern hunter-gatherers, including the Bushmen in Africa.

“Ancient humans exploited the fact that humans are good runners in the heat,” Dr. Bramble said. “We have such a great cooling system” — many sweat glands, little body hair.

There is other evidence that evolution favored endurance running. A study in The Journal of Experimental Biology last February showed that the short toes of the human foot allowed for more efficient running, compared with longer-toed animals. Increasing toe length as little as 20 percent doubles the mechanical work of the foot. Even the fact that the big toe is straight, rather than to the side, suggests that our feet evolved for running.

“The big toe is lined up with the rest, not divergent, the way you see with apes and our closest nonrunning relatives,” Dr. Bramble said. “It’s the main push-off in running: the last thing to leave the ground is that big toe.”

Springlike ligaments and tendons in the feet and legs are crucial for running. (Our close relatives the chimpanzee and the ape don’t have them.) A narrow waist and a midsection that can turn allow us to swing our arms and prevent us from zigzagging on the trail. Humans also have a far more developed sense of balance, an advantage that keeps the head stable as we run. And most humans can store about 20 miles’ worth of glycogen in their muscles.

And the gluteus maximus, the largest muscle in the human body, is primarily engaged only during running. “Your butt is a running muscle; you barely use it when you walk,” Dr. Lieberman said. “There are so many features in our bodies from our heads to our toes that make us good at running.”

So if we’re born to run, why are runners so often injured? A combination of factors is likely to play a role, experts say. Exercise early in life can affect the development of tendons and muscles, but many people don’t start running until adulthood, so their bodies may not be as well developed for distance. Running on only artificial surfaces and in high-tech shoes can change the biomechanics of running, increasing the risks of injury.

What’s the solution? Slower, easier training over a long period would most likely help; so would brief walk breaks, which mimic the behavior of the persistence hunter. And running on a variety of surfaces and in simpler shoes with less cushioning can restore natural running form.

Mr. McDougall says that while researching his book, he corrected his form and stopped using thickly cushioned shoes. He has run without injury for three years.

NY Times nutrition article

By GINA KOLATA

Published: July 19, 2010

Link here

Exercise scientists say they have stumbled on an amazing discovery. Athletes can improve their performance in intense bouts of exercise, lasting an hour or so, if they merely rinse their mouths with a carbohydrate solution. They don’t even have to swallow it.

It has to be real carbohydrates, though; the scientists used a solution of water and a flavorless starch derivative called maltodextrin. Artificial sweeteners have no effect.

And the scientists think they have figured out why it works. It appears that the brain can sense carbohydrates in the mouth, even tasteless ones. The sensors are different from the ones for sweetness, and they prompt the brain to respond, spurring on the athlete.

Many athletes depend on sugary beverages to keep them going. But often, when blood is diverted from the stomach to working muscles during intense exercise, drinks or foods cause stomach cramps. So a carbohydrate rinse can be a way to get the same effect.

“You can get an advantage from tricking your brain,” said a discoverer of the effect, Matt Bridge, a senior lecturer in coaching and sports science at the University of Birmingham in England. “Your brain tells your body, ‘Carbohydrates are on the way.’ ” And with that message, muscles and nerves are prompted to work harder and longer.”

It’s a relatively small effect, said George A. Brooks, an exercise researcher at the University of California, Berkeley, who was not involved with the research. But a small difference, he added, “can make a big difference in competition.”

The discovery began with some puzzling findings dating to the 1990s.

Until then, exercise scientists thought they knew why it could help to eat or drink carbohydrates during a long endurance event like a marathon. Muscles can use up their glycogen, the storage form of glucose, during long exercise sessions. But if athletes consume carbohydrates, they can provide a new source of fuel for their starving muscles.

That theory predicts that carbohydrates should have no effect on performance in shorter races, an hour or less. Muscles can’t use up their glycogen that fast, and by the time the body metabolizes the carbohydrates for fuel, the race is almost over.

Then came a handful of studies showing that carbohydrates did have an effect in short exercise sessions. Athletes, often trained cyclists, rode hard and fast for an hour or so after drinking either a beverage containing carbohydrates or one that tasted the same but contained an artificial sweetener.

In intense exercise sessions lasting more than half an hour, the athletes were able to go faster or keep going longer when they had the drink with carbohydrates. Their performance improved as much as 14 percent.

Some studies, though, did not find an effect. And the difference seemed to be that athletes who were hungry showed improved performance.

It made no sense. Could the body somehow have metabolized the carbohydrates in the drinks and put them to use in such a short time? Did the muscles even need carbohydrates in such short bouts of exercise?

Asker Jeukendrup, an exercise physiologist at the University of Birmingham, and his colleagues put that idea to the test. They were among the first researchers to discover a carbohydrate effect in cyclists riding hard for an hour, and they had been puzzling over what could account for it.

So they gave trained cyclists intravenous infusions of glucose or, as a control, intravenous salt water, before asking them to ride as fast as they could for about 24 miles, about an hour. The intravenous glucose meant the athletes had large amounts of sugar available right away — no digestion required. But it had no effect on their performance.

Next they tried what seemed like a crazy idea. They asked the cyclists to do the same ride, but first to rinse their mouths with the maltodextrin solution (or, as a control, with water).

“The results were remarkable,” the researchers wrote. Just rinsing with a carbohydrate had the same effect as drinking it.

Other scientists repeated the experiment. One group used runners, asking them to run for 30 minutes or, in another study, 60 minutes. Rinsing the mouth with carbohydrates consistently led them to run farther, as compared with rinsing with placebos.

Dr. Jeukendrup and his colleagues continued to tweak the study conditions. What happened, they asked, if athletes ate breakfast before rinsing with carbohydrates, or drinking a carbohydrate solution? Then, they found, carbohydrates had no effect.

Meanwhile, neuroscientists found that rodent brains, at least, responded to carbohydrates in the mouth independently of their response to sweetness. It is carbohydrates that matter, and so artificial sweeteners do not stimulate these pathways that go from the mouth to the brain.

Then Dr. Bridge and his colleagues in Birmingham used functional magnetic-resonance imaging to determine whether glucose, which tastes sweet, has the same effect on the brain as the tasteless carbohydrate maltodextrin. They also tested artificial sweeteners for comparison. The brain scan results confirmed the exercise study results: Carbohydrates activated brain areas involved with rewards and muscle activity. Artificial sweeteners did not.

Is rinsing worthwhile for most athletes? Scott J. Montain, an exercise researcher at the United States Army Research Institute of Environmental Medicine, thinks not. The effect is real, he said, but added, “Endurance competitors are better off just consuming the calories.” That way they get real fuel, instead of “sipping and then spitting out expensive, sticky spit.”

Dr. Jeukendrup and Dr. Bridge, though, say they use the mouth-rinsing trick themselves.

“You do notice a benefit,” Dr. Bridge said. But he noted that in a study, the athletes don’t know if they are getting carbohydrates or not. “If you know you are doing it,” he said, “then there’s a chance it’s a placebo effect.”

You might be a runner if.....

...your toenails are black.
...your shoes have more miles on them than your car does.
...you need a magnifying glass to see your name in the paper.
...you have chafing in strange places.
...people say, "You run three miles...at once?"
...all your socks are either stained or torn.
...your underwear covers more than your uniform shorts.
...you run farther in a week than your bus travels for meets.
...the dogs have to hurry to keep up.
...you find yourself running between classes just because.
...the most enjoyable time you've had all month is a day off from practice.
...your coach won't give you a ride home.
...the first day of practice you run 5 miles but your coach says you only ran 2.
...you can spit while running.
...you go to a golf course to run.
...your friends go on the elevator and you beat them on the stairs.
...you finish the race looking like you wrestled a bear and you don't care.
...your temper is shorter that the distance that you ran.
...you'd rather run to school than drive.
...you combine phrases like "10 mile run" and "Easy Run" in the same breath.
...you can eat your weight in spaghetti.
...your highest heels are your training shoes.
...you debate the advantages of anti-perspirent vs. deoderant.
...the paint from the bathroom walls peels when you leave.
...you start the race in shorts and finish in a G-string.
...your spit strings from you chin and you don't even care.
...a meal involves more than 3 servings!
...if you schedule dates around meets.
...you spend more on training clothes than school clothes.
...you wear those same training clothes to school regularly.
...your christmas list includes more than one pair of running shoes.
...you've been to a golf course in every city but not to play golf.
...your entire family goes to X-C meets because they have been or will be on the team.
...your chest is as flat as your back.
...you feel lost without your water-bottle.
...you have running withdrawl if you don't run everyday.
...you eat spaghetti three times a day.
...the mile in P.E. becomes your warm-up.
...you wake up every morning in pain.
...gatorade is your drug of choice.
...you give up homecoming to go to a Meet.
...your Saturdays for the next 4 years are ruined.
...you can see your ribs thru your shirt.
...you have to run around in the shower to get wet.
...you were asked to be an extra for Schindler's List II.
...you enjoy running hills.
...you start to crave Power Bars.
...your favorite food group is carbohydrates.
...your women's team has leg hair longer than the grass they ran on.
...you can strip and change in a bus seat in less than 2 minutes.
...you don't puke your first day of basketball practice.
...there are no flies by your gym locker.
...people think it's a winter sport.
...you have trouble benching the bar.
...when you do bad you get to play longer.
...you find yourself in the middle of a football player's joke.
...your dessert is brussel sprouts.
...you foam at the mouth.
...you are always hungry.
...your running in your dreams.
...you have no life besides running.
...your weekends are shot.
...you wake up with cotton mouth.
...your are as skinny as a twig and have a stupid knit cap for the head.
...you can sharpen an axe blade on your calves.
...the cafeteria ladies look good in the morning.
...you can maintain a 5:30 pace uphill while throwing up.
...you think track is for wussies.
...you try to impress girls by saying you're a fast finisher.
...you consider school as just a break between runs.
...you always stretch while waiting in the lunch line.
...your room smells like Icy-Hot and New-Skin.
...you are bankrolling your physical therapist's next vacation.
...your girlfriend can bench more than you.
...you can count all your ribs.
...you own spandex in more than 1 color.
...track is the other "sport".
...you foam at the mouth everytime you see a big hill.
..."Chariots of Fire" is actually entertaining to you.
...a 12 mile run is an easy day.
...pizza, pasta, pizza, & pasta are your four food groups.
...your watch is more expensive and complicated than your car.
...even your dress shoes have spikes.
...Runner's World provides more pin-ups than Playboy (YEAH SUZY HAMILTON!!!)
...Steve Prefontaine's Birthday is more important than yours.
...you aspire to pain.
...you know as many kinds of pain as eskimos have words for snow.
...you think spandex is a winter's passion statement.
...you never look behind you.
...you don't know what an "off-season" means.
...you have stress fractures.
...you find yourself saying, "it's not really a hill..."
...you hit targets with your snot rocket.
...your feet are comparable to rawhide.
...you're running and you don't know why.
...you see a hill on a putting green.
...your friends refer to you as "the masochist".
...your spit hits everything but the ground.
...you drink more water than Free Willy
...you can't get the "All you can eat" at spaghetti restaurants
...you get pulled over after practice, and can't walk straight because you're so tired
...you ran sub 5 on the P.E. mile run
...you wore spikes on the P.E. mile run
...you did a 30 minute warm up for the P.E. mile run
...you did all of the above for the P.E. mile run
...you routinely race dogs down the street...and win.
...dogs follow you everywhere you go
...you rabbit for the rabbit
...you have 3% or less body fat
...you laugh at sprinters while they run
...theres nothing like intervals to start the week off fresh!!
...you talk to your coaches more than your parents
...you'd rather run than watch T.V.
...watching the New York Marathon on T.V. made you get up and go for a run
...you can say "I like to run" in over five different languages
...more than half the people you know don't know what X-C is
...you run the day after State
...off-season training starts a week after State
...you haven't had a pop in 6 months
...your calves are bigger than your biceps
...your cookie jar is filled with bagels
...there are more miles on your running shoes than the odeometer of your car
...you try to pick up a girl by telling her how fast your first mile is
...you're toe nails are fallen off
...a fatman with a gun says alright gentlemen take em off
...you can't go a day without some little brat saying run forest run
...some little kid wants to know why you're running in your underwear
...you can pronounce those funny Kenyan names
...you're proud that another team has quadrupled you're score
...the seniors assist the freshman into the lake
...you wear skimpier clothes than Madonna
...you refer to puke as a normal bodily function
...people always ask you what events you are running
...you can hallucinate and get high at the same time without taking anything
...you can say more names of your runs than names of your friends
...you spend more time thinking about the scoring system than you do about scoring with
the opposite sex
...you always win in your sleep but never in a real race
...you traded in your Gremlin
...you think Lisa Aguilera is hotter than Christina Aguilera.
...you wake up in the morning and find that you?re already running.
...the Ritz is your idol, and not a hotel in New York.

Read more: http://www.letsrun.com/forum/flat_read.php?thread=9545#ixzz0u8uxNq88

Belly-buttons key to success in sport: study

Who could have guessed it?

By Karin Zeitvogel (AFP) – 2 days ago
WASHINGTON — Scientists have found the reason why blacks dominate on the running track and whites in the swimming pool: it's in their belly-buttons, a study published Monday shows.
What's important is not whether an athlete has an innie or an outie but where his or her navel is in relation to the rest of the body, says the study published in the International Journal of Design and Nature and Ecodynamics.
The navel is the center of gravity of the body, and given two runners or swimmers of the same height, one black and one white, "what matters is not total height but the position of the belly-button, or center of gravity," Duke University professor Andre Bejan, the lead author of the study, told AFP.
"It so happens that in the architecture of the human body of West African-origin runners, the center of gravity is significantly higher than in runners of European origin," which puts them at an advantage in sprints on the track, he said.
Individuals of West African-origin have longer legs than European-origin athletes, which means their belly-buttons are three centimeters (1.18 inches) higher than whites', said Bejan.
That means the black athletes have a "hidden height" that is three percent greater than whites', which gives them a significant speed advantage on the track.
"Locomotion is essentially a continual process of falling forward, and mass that falls from a higher altitude, falls faster," Bejan explained.
In the pool, meanwhile, whites have the advantage because they have longer torsos, making their belly-buttons lower in the general scheme of body architecture.
"Swimming is the art of surfing the wave created by the swimmer," said Bejan.
"The swimmer who makes the bigger wave is the faster swimmer, and a longer torso makes a bigger wave. Europeans have a three-percent longer torso than West Africans, which gives them a 1.5-percent speed advantage in the pool," he said.
Asians have the same long torsos as Europeans, giving them the same potential to be record-breakers in the pool.
But they often lose out to whites because whites are taller, said Bejan.
Many scientists have avoided studying why blacks make better sprinters and whites better swimmers because of what the study calls the "obvious" race angle.
But Bejan said the study he conducted with Edward Jones, a professor at Howard University in Washington, and Duke graduate Jordan Charles, focused on the athletes' geographic origins and biology, not race, which the authors of the study call a "social construct."
Bejan is white, originally from Romania, and Jones is black, from South Carolina.
They charted and analyzed nearly 100 years of records in men's and women's sprinting and 100-meters freestyle swimming for the study.

What Motivates Us?

First white man ever to break 10 sec for 100m. Slow Mo.

Principles of Training -Nic Bideau Article

This article offers insights into proper training. Nic has coached Craig Mottram and Benita Willis to remarkable successes.
Click here

The Tour Begins

I've always found it quite interesting to watch the drug related foibles of the tour. This is the cutting edge when it comes to drugs in sport, partly because it is such a grueling event.
Great article from the Wall Street Journal
Check out the Timeline too.