Garden Grocer Food for Thought

Heart attack symptoms tend to differ in women and men.

Sudden chest pain is the hallmark symptom of a heart attack. But a large new study shows that many people who are taken to hospitals for heart attacks never have chest pain and, as a result, are less likely to be treated aggressively.

The consequences may be especially deadly for younger and middle-aged women. In a new study of 1.1 million people, a surprising 42 percent of women admitted to hospitals for heart attack never had chest pain. By comparison, just 30.7 percent of men who were admitted didn’t experience chest pain. Women were also more likely to die after a heart attack; the mortality rate for women in the study was nearly 15 percent, compared with 10 percent for men.

“We think part of the reason is that women who are presenting with a heart attack might not have that classical presentation,” said Dr. John G. Canto, director of the chest pain center at Lakeland Regional Medical Center in Florida and an author of the study, which was published in The Journal of the American Medical Association. “So they may not be recognized as having a heart attack, and possibly some of these patients may present too late to receive lifesaving procedures.”

Heart disease is the leading cause of death among men and women, not just in the United States but around the world, killing about seven million people a year. Until the 1980s, heart disease was largely considered a male problem, and many studies that focused only on men drew a narrow picture of the typical signs of heart attack: chest pain, shortness of breath and radiating pain in the neck, back, jaw and arms. But more inclusive research since then has shown that while female heart patients may exhibit these symptoms, they are also more likely to show symptoms that are less typically associated with heart attacks, like sleep disturbances and severe unexplained fatigue in the days and weeks prior, as well as cold sweats, weakness and dizziness during the attack.

In their new study, Dr. Canto and his colleagues used data from a national registry of people admitted to hospitals for heart attack from 1994 to 2006 to look at differences in symptoms and mortality rates among men and women. The analysis, covering 1,143,513 people, showed that chest pain is in fact the most frequent symptom of a heart attack in both men and women. But a sizable minority of patients, about 35 percent over all, never had chest pain.

Women under 55 who had heart attacks but no chest discomfort had two to three times the risk of dying in the hospital compared with men of the same age with classic heart attack symptoms. But “the difference markedly declined and nearly disappeared with increasing age,” said Dr. Canto, who is also the director of cardiovascular prevention research and education at the Watson Clinic in Lakeland.

No one knows precisely why heart attack symptoms differ between men and women, but Dr. Canto speculated that many factors may be involved, including hormones. Many women who take birth control pills, for example, tend to have “stickier” blood vessels and arteries than men, he said.

“We also know that in women, especially young women who have heart attacks, the mechanism of blood clot formation in the heart artery may be different than in young men,” he said. “They tend to involve more plaque erosion and sloughing off rather than the plaque rupturing, which is the classic way that heart attacks occur.”

Those who are having a heart attack but do not feel tightness or pain in the chest may not realize what is happening, Dr. Canto said, and when they do show up for treatment, doctors may not immediately consider the possibility of a heart attack, particularly in women. As a result, the odds of immediately undergoing bypass surgery, heart catheterizations and other lifesaving procedures are decreased.

The reality is that many doctors tend not to think that younger women have heart attacks, said Dr. Mario Garcia, a member of the American Heart Association and chief of cardiology at the Montefiore Einstein Center for Heart and Vascular Care in New York. But it’s also known from other studies that even women who do experience classic symptoms of a heart attack, including chest pain, are less likely to seek medical attention than men.

“Men are quick to rush to see a physician,” said Dr. Garcia, who was not involved in the study. “Women worry more about their husbands than themselves.”

Article source: http://well.blogs.nytimes.com/2012/02/22/many-heart-attacks-dont-cause-chest-pain/

Andrew Burton/Associated Press

A few weeks ago, a friend showed up for a run with a CamelBak — one of those humplike backpacks with a tube that allows you to sip liquid — and a belt containing food to eat along the way. Every 20 minutes or so as we ran, he stopped to eat and drink, sprinting afterward to catch up.

Now that is unusual, I thought. Does it really help to eat so often during a 16-mile run?

Certainly a lot of athletes believe they need constant nourishment. My friend and running partner Jen Davis, who has entered more races and run more than I ever have, once went on a 30-mile training run with a guy wearing a CamelBak and bearing snacks. He stopped every 20 minutes along the way and then, about halfway through the run, pulled out a turkey sandwich.

“I’m not sure if he ever actually ran an ultra race,” Jen said. “He may have gotten injured after carrying that heavy pack on those long runs.”

There is no end to the crazy foods people will eat at endurance events. At the J.F.K. 50-Mile in Maryland, boiled potatoes and chicken broth are provided at aid stations. At the Rocky Raccoon Endurance Trail Run in Texas, runners can choose rice and beans or pasta, along with snacks like pretzels, cookies and candy.

At a 100-mile bike ride my husband and I have done several times, pumpkin pie is offered about 25 miles from the finish line. (My husband tried it one year and felt ill the rest of the ride.)

For the athlete determined to munch on the go, there are shelves worth of prepackaged “energy gels” and bars, even jelly beans, promising to raise performance.

But most athletes are not running 30 or 50 or 100 miles, nor are they doing the equivalent amount of exercise in another sport, like cycling or swimming or skiing. So most of us really do not need to keep eating during a race to maintain energy and stamina, said Nancy Rodriguez, a sports nutritionist at the University of Connecticut.

Dr. Rodriguez reviewed published studies on nutrition and performance as part of a group of experts who wrote a position paper on the topic for the American College of Sports Medicine. Runners, for example, competing in a 5- or 10-kilometer race, she said, “don’t need the CamelBaks and don’t need to have that Hershey bar or Powerade or Clif shot.”

Even athletes who are fast and competitive may not always need to eat during a workout. There’s no set rule on what they should eat and drink before, during and after exercise, said Melinda M. Manore, a sports nutritionist at Oregon State University who was an author of the position paper.

“People have gotten the message that they have to eat something,” Dr. Manore said. They guzzle an energy drink or eat a sports bar, but that doesn’t help. And for the many who are trying to lose weight, the habit just adds extra calories.

What they need depends on what they ate before they started and how hard their workout is going to be, among other things, she explained. “If you can run six-minute miles or five-minute miles and you are going out for an hour, you do not need to be eating an energy bar during the workout,” Dr. Manore said.

Moderate athletes need to eat and drink after the workout, she said, but a healthy meal with plenty of fluids is sufficient. Indeed, for most of them, the most common error is to eat too much.

Dr. Manore follows her own advice. She hikes for an hour in the hills every morning, four to five miles. All she has before she goes out is a cup of tea with milk.

But anyone exercising for two hours or more does need to get carbohydrates, the muscles’ fuel, according to the position statement. That means eating before, and perhaps during, the workout.

Those who try to skimp can end up with a poorer performance, said Daniel Bernadot, a sports nutrition researcher at Georgia State University. A long workout, like a run that lasts more than two hours, is “an enormous drain on blood sugar,” he said.

If the body runs out of glucose for fuel, it will start breaking down muscle, which is counterproductive. Dr. Bernadot’s research indicates that athletes do best when they never let themselves have more than a 400-calorie deficit during the day. That is, if you expend 1,500 calories on a two-hour run, you offset it with at least 1,100 calories in food that day.

That means it is a disadvantage to eat most of the day’s calories at one time — at night, for example. But athletes should make dietary changes gradually so their bodies can adapt to more frequent fueling, he said. Those who try sudden changes sometimes pay a price.

Dr. Bernadot tells the story of a distance runner who was doing well and felt great the morning of a big marathon. Before the race began, she saw her chief competitor put packs of a sugary gel into her running bra to eat during the race.

The distance runner did the same, even though she had never before eaten during races or long runs. It was a disaster: She had diarrhea during the event.

The gels “were anything but a competitive advantage,” Dr. Bernadot said.

“You have to let your body adapt,” he added. “And you have to find out what works for you.”

Article source: http://well.blogs.nytimes.com/2012/02/20/workouts-may-not-be-the-best-time-for-a-snack/

Andrew Scrivani for The New York TimesVeracruzana Chicken Stew With Winter Squash

There are as many kinds of stews as there are cooks, blending meats, seafood, vegetables and spices into a hearty and flavorful melange. This week, the Recipes for Health columnist, Martha Rose Shulman, turns her attention to chicken stews:

I wanted each of these stews to feature a nutritious vegetable along with the chicken and aromatics. In this way they are truly one-dish, nutrient-dense meals. Though I suggest serving them with rice, other grains or pasta, if carbs are an issue, know that these stews are very satisfying on their own.

Here are five new recipes for making chicken stew.

Greek Chicken Stew With Cauliflower and Olives: Cinnamon adds a subtle sweetness to this stew. If salt is an issue, omit the olives; the stew will still be delicious.

Chicken Stew With Sweet Potatoes, Almonds and Apricots: Loosely based on an Algerian recipe from “Real Stew” by Clifford A. Wright, this sweetly spiced dish, with beta-carotene-rich apricots and sweet potatoes, is also evocative of recipes from the Middle East and Iran.

Chicken Cacciatore With Mushrooms, Tomatoes and Wine: This version of the classic Italian dish includes lots of mushrooms, both dried and fresh; you can add kale if you want to work in some leafy greens.

Chicken and Pepper Stew: This is an adaptation of a classic French bistro dish, poulet Basquaise.

Veracruzana Chicken Stew With Winter Squash: This dish is loosely based on a chicken stew from the Mexican state of Veracruz, where Spanish influences still remain strong.

Article source: http://well.blogs.nytimes.com/2012/02/17/a-chicken-in-every-stew-pot/

One of the most agonizing spots in medicine is the “transplant list.” When I’ve referred patients for organ transplant — heart, liver, kidney — it is the start of an anguished wait. The clock ticks for my patient as we watch her clinical status decline, all the while harboring that excruciating hope that someone will die soon enough to make an organ available. In the case of kidney donation, which can come from a live donor, it is the desperate hope that someone will decide to make this enormous personal sacrifice.

Some of my patients have died waiting, which is, sadly, not an unusual outcome. It is estimated that 18 patients on the waiting list in America die every day. In the United States, as in many countries, we rely on a simple system of altruism, or what might be called the opt-in approach. We hope that people will sign organ donor cards because they think it is the right thing to do, or that families will consent to donation after a loved one has had brain death because it will help someone else. But these mechanisms do not result in nearly enough organs for all the patients who need them.

Other countries, like Spain and Austria, have tried an opt-out approach, called presumed consent. Every patient who dies is assumed to have consented to organ donation, unless they have specifically declined. However, this hasn’t necessarily increased the number of organ donations, in part because doctors find it extremely difficult to go against family wishes if surviving family members are strongly opposed to donation.

A third way to increase donations is being pioneered in Israel. Until now, Israel ranked at the bottom of Western countries on organ donation. Jewish law proscribes desecration of the dead, which has been interpreted by many to mean that Judaism prohibits organ donation. Additionally, there were rabbinic issues surrounding the concept of brain death, the state in which organs are typically harvested. As a result, many patients died waiting for organs.

So Israel has decided to try a new system that would give transplant priority to patients who have agreed to donate their organs. In doing so, it has become the first country in the world to incorporate “nonmedical” criteria into the priority system, though medical necessity would still be the first priority.

Dr. Jacob Lavee

It began as the brainchild of Dr. Jacob Lavee, a cardiothoracic surgeon who heads the heart transplant program of Sheba Medical Center in Tel Hashomer. In 2005, he had two ultra-Orthodox, Haredi Jewish patients on his ward who were awaiting heart transplants. The patients confided in him that they would never consider donating organs, in accordance with Haredi Jewish beliefs, but that they had absolutely no qualms about accepting organs from others.

That Haredi Jews would not donate organs was a well-known fact in Israel. But this was the first time anyone had openly admitted the paradox to Dr. Lavee.

The unfairness of a segment of society unwilling to donate organs, but happy to accept them, nagged at Dr. Lavee. After he operated on both patients, giving each a new lease on life, he put together a proposal that would give priority to those patients willing to donate their organs.

Working with rabbis, ethicists, lawyers, academics and members of the public, he and other medical experts worked to create a new law in 2010, which will take full effect this year: if two patients have identical medical needs for an organ transplant, priority will be given to the patient who has signed a donor card, or whose family member has donated an organ in the past.

A critical component of the law’s success was engaging the country’s highly influential religious leadership, which had long been resistant to organ donation. Even among the half of the country that is devoutly secular, when faced with death and whether to donate organs. “Suddenly the families become very religious,” said Dr. Yael Haviv, the medical director of the organ donation program at Sheba. “Suddenly they ask the rabbis.”

But in the Talmud, saving a life supersedes most everything, and many commandments may be transgressed if the goal is to save a life. Based on this, the argument could be made that organ donation fulfilled one of the highest religious virtues. The lawmakers also agreed on a definition of brain death that was acceptable to the vast majority of rabbis (though not the ultra-Orthodox Haredi), as well as local imams, making organ donation kosher to a large segment of the population.

This was accompanied by a huge public awareness campaign about organ donation, with radio, TV, billboard and newspaper ads promoting the new priority system and countering the perception that Jewish law forbids donation. Shopping centers and coffee houses were blanketed with organ donation information. The response was overwhelming, as people registered in droves as potential donors.

“We were swamped,” says Tamar Ashkenazi, the director of the National Transplant Center of Israel. The machine that prints the organ donation cards usually handles 3,000 a month — 5,000 if two workers are dedicated full-time to operating it. During the 10 weeks of the publicity campaign, 70,000 Israelis registered for organ donation cards.

The consent rate from families has already increased, and the number of organs available for patients has increased in parallel. Transplants have so far increased by more than 60 percent over all this year.

Other aspects of the new law provide “fair compensation” for living donors that covers 40 days of lost wages, plus expenses related to the donation. “This serves to remove the disincentives to donation,” Dr. Lavee says. Kidney transplants from live donors — nearly always from family members of patients — increased dramatically.

The new system, though, is not without its critics. Many say that any “nonmedical” factors in organ allocation are inherently unethical. Some say that the law enshrines religious discrimination, since Haredi patients decline to donate based on their religious beliefs.

But many feel that the new law adds a measure of fairness to the process, and now there are more organs available for everyone. It will be interesting to see how things play out when the priority system goes into effect on April 1.

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Danielle Ofri is the author of three books, including “Medicine in Translation: Journeys With My Patients.” She is an associate professor of medicine at New York University School of Medicine and editor in chief of the Bellevue Literary Review.

Article source: http://well.blogs.nytimes.com/2012/02/16/in-israel-a-new-approach-to-organ-donation/

Eden ZaslowFATHER FIRST Much of Jeffrey Zaslow’s writing centered on the theme of love.

Several years ago, my friend Jeffrey Zaslow sent me a chapter from a book he was writing about lifelong friendships among a group of women from Ames, Iowa. It was a powerful story about love and loss that moved me to tears.

With the draft pages still in my hands, I sat down with my daughter, a second-grader at the time, to talk about the importance of friendship. We talked about her girlfriends, why occasional fights didn’t matter and why she should always treasure her friends. It was a sweet moment, and I was grateful to Jeff for inspiring the conversation through his writing.

Later, I called him to tell him how much that single chapter had meant to my daughter and me. How, I asked him, had he managed to inject himself into this circle of women he had only recently met and so accurately depict the power of female friendship?

“I have a wife and three daughters,” he said, laughing, without missing a beat. “I’m quite comfortable being outnumbered by women.”

I thought about our conversation this weekend when I learned the terrible news that Jeff had died in a car accident on snowy roads on his way to his Detroit-area home, returning from a book-signing event in northern Michigan. “The Girls From Ames” became a best seller, and remains my favorite among the books he wrote. But many people know Jeff as co-author of “The Last Lecture,” with the Carnegie Mellon professor Randy Pausch, who delivered that now famous lecture after learning he had pancreatic cancer.

Mr. Zaslow was also co-author of memoirs with Gabrielle Giffords, the congresswoman from Arizona who was recovering from a gunshot wound to the head, and Chesley B. Sullenberger III, the pilot who safely ditched a damaged airliner on the Hudson River in 2009. Despite the disparate subject matter, Mr. Zaslow noted that much of his writing centered on the theme of love, commitment and living in the moment.

“We don’t know what moment in our lives we’re going to be judged on; that’s true for all of us,” he said at a TED talk last year, explaining what he had learned from Captain Sullenberger. “We’ve got to be honorable, be moral; we’ve got to work our hardest.”

Despite his success as a memoir co-author, Jeff’s true labor of love was his latest book, “The Magic Room: A Story About the Love We Wish for Our Daughters.” Dedicated to his daughters, the book focused on a bridal shop in Fowler, Mich., as a way to tell a story of parents’ hopes and dreams.

Mr. Zaslow’s role as a father was a common theme in his work, one he loved to talk about. Once when a boy canceled plans to take his daughter to a homecoming dance, Mr. Zaslow said he thought to himself, “What can I do for my sad daughter?” He decided to embarrass the boy in front of millions by writing a Wall Street Journal column about the lessons parents should be teaching their sons.

“The lesson of the story — and of that night — is to teach your sons to be chivalrous, and your daughters not to take it,” he said in a 2009 interview. “My daughter was not thrilled. And the boy was not thrilled. But you know what? The next time you want to take my daughter to the dance, follow through.”

Jeff often said he honed his skills for listening and offering advice during a stint as an advice columnist, a role he won in a contest to replace Ann Landers. During his many public talks, Jeff told the story of a favorite letter from a man who wanted his girlfriend, Julie, to undergo breast augmentation.

“Julie deserves someone who loves her for who she is, not how she looks in a sweater,” Jeff wrote in his reply. “If you can’t do that for her, she won’t need implants anyway because she will already have a big boob in her life. You.”

In every conversation I had with Jeff and in much of his writing, he talked about how much he had learned about the frailty of life and the importance of never leaving important words unsaid.

At his TED talk last November, Jeff told the audience about a column of his that focused on the words “I love you.” It appeared two days before Valentine’s Day in 2004, and led with the story of a judge in Maywood, Ill., who often told his children that he loved them. One day in 1995, as his 18-year-old daughter was leaving the house, the judge called out to his daughter. “Kristin, remember I love you,” he said.

“I love you too, Dad,” the girl replied. That day, Kristin was killed in a car accident. It was a story that resonated with Jeff, and one he took to heart, always saying “I love you” to his wife and daughters before saying goodbye or hanging up the phone.

“All of us should say ‘I love you’ to the people we care about,” Jeff said. “We should do it because you never know. I got about 1,000 e-mails from readers saying they were going to tell their children they loved them.

“What I like about my job is sometimes I’m just writing about the obvious. By doing that, you can touch a lot of people and tell them things that will change their lives, even if it’s something simple.”

Article source: http://well.blogs.nytimes.com/2012/02/13/lifes-frailty-and-the-gestures-that-go-a-long-way/

Andrew Scrivani for The New York TimesSauteed Shredded Winter Squash and Cabbage and a Winter Vegetable Gratin

Salad is great for summer, but winter meals demand heartier fare. Consider heating up your dinnertime with these hot and flavorful vegetable dishes from Martha Rose Shulman. She writes:

I made two great discoveries while coming up with these simple and delicious vegetarian skillet suppers. One is that a wok should not be limited to Asian stir-fries. A well-seasoned carbon steel wok makes a great natural nonstick pan that you can get hot enough to obtain a wonderful seared flavor when you cook vegetables, no matter what the seasonings.

The other thing I discovered is that the cooking water drained off from cooked barley or brown rice can be added to cooked vegetables the way pasta cooking water is sometimes used to moisten and add texture to an accompaniment. The starch in the nutrient-dense water enriches the vegetables like a sauce. Just add more water than the usual proportion that you’d use — say a quart for a cup of brown rice or barley — and drain the grains through a strainer set over a bowl when they’re tender.

Simmered Beet Greens With Roasted Beets, Lemon and Yogurt: The Greeks serve this dish as a salad, but if you want to make a meal of this, serve the greens and beets with a whole grain, like barley or quinoa.

Skillet Mushrooms and Chard With Barley or Brown Rice: Mushrooms and barley are a classic combination, but brown rice is also very nice with this dish, and it cooks faster.

Cauliflower, Brussels Sprouts and Red Beans With Lemon and Mustard: You can cook this beautiful, lemony skillet dinner in a well-seasoned wok or a heavy nonstick pan. You’ll get the best seared flavor in a wok.

Sautéed Shredded Winter Squash and Cabbage and a Winter Vegetable Gratin: You can just cook these vegetables in a skillet and serve them with grains for a great vegan dinner, or turn them into a hearty vegetarian (but not vegan) Provençal-style gratin.

Skillet Collards and Winter Squash With Barley: Barley water is used to make nutritious beverages in many cuisines; it can also be useful as a sort of sauce, adding rich flavor and texture to vegetables.

Article source: http://well.blogs.nytimes.com/2012/02/10/hot-vegetables-for-cold-weather/

Kevin P. Casey for The New York TimesSmall premature babies born by Caesarean section are at increased risk of respiratory distress syndrome, a new study has found.

Very small babies delivered prematurely by Caesarean section because they were not growing properly in the womb developed more respiratory problems than those who had induced vaginal deliveries, a new study found. The study adds to growing concern over the high rate of Caesarean section deliveries in the United States, which reached 32 percent, or nearly one in three deliveries, in 2007.

On Wednesday, the federal secretary of health and human services, Kathleen Sebelius, announced a public health campaign to educate families that it is best for both the mother and the baby to let a problem-free pregnancy go for as long as possible, and to let labor start naturally. The campaign is a partnership that expands on a March of Dimes public awareness drive emphasizing that “healthy babies are worth the wait.”

The latest study looked at babies who were extremely small for their gestational age and not growing properly in utero, so waiting was not a medical option. But the findings raise new questions about the risks of Caesarean section.

For the study, researchers analyzed nine years of data from births in New York City, identifying 2,560 babies who were small for their gestational age and delivered between 25 and 34 weeks of pregnancy. Forty-six percent were delivered vaginally, and 54 percent by Caesarean section.

“The conventional thinking, though nobody really knew, was that maybe it would be less traumatic for this group to have a C-section, and they might benefit,” said Dr. Erika F. Werner, an assistant professor at Johns Hopkins School of Medicine and the study’s lead author. “Our study suggests that may not be true.”

In fact, the babies delivered by C-section were 30 percent more likely to develop respiratory distress syndrome, a serious breathing disorder that can lead to organ damage and that is more common in premature infants, Dr. Werner and colleagues from Brown and Yale Universities found.

The C-section deliveries were not associated with improved outcomes in terms of other complications, including hemorrhages, seizures, low Apgar scores and sepsis, the researchers found. Results were adjusted for differences in the mother’s age, ethnicity, education, health status and weight.

The findings are being presented today at the annual meeting of the Society for Maternal-Fetal Medicine in Dallas.

“The takeaway is that if you’re in this situation, you should have a frank discussion with your doctor that maybe a vaginal delivery is equivalent, or even better,” Dr. Werner said. “We need further research to determine if there is any benefit to C-section” for such infants, she said.

Another consideration is that when a woman has one baby born by Caesarean section, subsequent children are far more likely to be delivered by C-section as well.

As to why vaginal deliveries appear to improve respiratory function, Dr. Werner said, “We don’t have the perfect answer.” Some experts believe that the physical compression the baby experiences during labor helps remove fluid from the lungs and prepares the baby to breathe air.

Dr. Diane M. Ashton, deputy medical director of the March of Dimes, who has been overseeing the organization’s Prematurity Campaign to educate the public, said similarly improved outcomes are seen with infants delivered further along in a pregnancy.

“This is consistent with what is seen in infants even at 37 weeks,” she said. “They, too, have better respiratory outcomes when delivered vaginally versus C-delivery.”

Studies suggest that premature births of single babies have been increasing in recent years and that more are being delivered by Caesarean section, including C-sections that are not medically necessary. At the same time, recent research shows that a baby’s lungs and brain undergo important growth and development during the last few weeks of pregnancy, and that babies born just three to six weeks before their due dates are more likely to suffer disabilities or developmental delays in kindergarten.

Last year, the American College of Obstetricians and Gynecologists issued new medical guidelines meant to lower the rate of repeat Caesareans by making it easier for women to find doctors and hospitals that will let them attempt a vaginal delivery even when a previous baby was delivered by C-section. Although these women are at risk for a serious complication called uterine rupture, ruptures affect fewer than 1 percent of women, while C-sections, which involve major abdominal surgery, carry many other risks both to the mother and to the child.

Article source: http://well.blogs.nytimes.com/2012/02/09/c-sections-pose-respiratory-risks-for-some-small-preemies/

Thomas Barwick/Getty ImagesDoes how you run affect how often you get injured?

The members of Harvard University’s men’s and women’s distance running squads are young, fast, fit, skinny, bright, disciplined and, without exception, dutiful. Every day during the cross-country and track seasons, they enter their mileage and pace into an online training Web site overseen by the team’s coaches and trainers.

They also, like most serious runners, get hurt with distressing frequency, often missing practice due to aching muscles or over-stressed bones. Each of those injuries, no matter how niggling, also gets duly reported and entered into the computer.

Meaning that these student athletes, in their high-achieving way, fashioned an excellent database through which to examine running-related injuries, as evidenced by a study published online last month in Medicine Science in Sports Exercise.

The study, for which researchers combed through four years’ worth of data about the Harvard runners, has produced the surprisingly controversial finding that how a person runs may affect whether he or she winds up hurt.

Running injuries are a topic of considerable interest to scientists in many disciplines, from biomechanics to evolutionary biology, as well as, of course, to runners. By most estimates, more than half of all runners, whether male or female, collegiate or long past, become injured every year.

But no one knows why so many runners get hurt, although a number of theories have been advanced, including the possibility that hard asphalt roads, lousy Western diets, too many miles, too few miles or high-tech running shoes cause or contribute to the problem.

But Adam I. Daoud, a graduate student in the Skeletal Biology Laboratory at Harvard and the lab’s director, Daniel Lieberman, an evolutionary biologist who co-wrote an influential 2004 paper suggesting that distance running guided the evolution of early man — with better runners earning more food and sex than plodders and passing along their genes — wondered if something simpler might be at work. They wondered whether how your foot hits the ground affects your injury risk.

Most of us who run nowadays strike the ground first with our heels, a pattern promoted by today’s well-cushioned running shoes. There’s suggestive evidence, however, including from Dr. Lieberman’s work, that early, unshod hunter-gatherers landed first on the balls of their feet. So, in recent years, some runners have decided that forefoot striking must be more “natural” and less likely to cause injuries.

But there has been no science to support that idea.

To look into the issue, Mr. Daoud, who had been on the cross-country team as an undergraduate, and Dr. Lieberman not only gained access to the team’s training database, they also gathered the team members and videotaped them.

No one is always a forefoot striker or a heel striker. Your form depends on many factors, including your speed, the terrain, whether you’re tired and so on. But most of us have a predominant strike pattern, and so it was with the 52 Harvard runners. Thirty-six, or 69 percent of them, were heel strikers, while 16, or 31 percent, were forefoot strikers. The proportions were similar regardless of gender.

More interesting was the distribution of injuries. About two-thirds of the group wound up hurt seriously enough each year to miss two or more training days. But the heel strikers were much more prone to injury, with a twofold greater risk than the forefoot strikers.

This finding, the first to associate heel striking with injury, is likely to fuel the continuing and not-always civil debate about whether barefoot running is better. (It hurts to hit the ground with your heel if you’re not wearing shoes.) But both Dr. Lieberman and Mr. Daoud, now a medical student at Stanford University, are quick to point out that their study did not in any way address the merits of going barefoot.

All of the Harvard runners wore shoes, and most, as Dr. Lieberman says, “wore different shoes every day of the week.” Some ran in well-cushioned shoes and became injured, while others did not. Likewise for those who usually ran in minimal racing flats. Some got hurt; some did not. And forefoot striking, over all, was not a panacea. Many of the forefoot strikers were felled by injuries.

But in general, those runners who landed on their heels were considerably more likely to get hurt, often multiple times during a year.

Does this mean that those of us who habitually heel-strike, as I do, should change our form? “If you’re not getting hurt,” Dr. Lieberman says, “then absolutely not. If it’s not broke, don’t fix it.”

But, says Mr. Daoud, who was himself an oft-injured heel-striker during his cross-country racing days, “if you have experienced injury after injury and you’re a heel-striker, it might be worth considering a change.” (If you’re unsure of your strike pattern, have a friend videotape you from the side as you run, he suggests, then use slow motion to watch how your foot hits the ground.)

If you do decide to reshape your stride, proceed slowly, he cautions. Many people who abruptly switch to barefoot running or a forefoot running form get hurt in the process, he says. The body’s tissues adapt to the forces generated by long-term heel striking. Change your form, and the forces will affect different parts of the leg, leading to soreness and, potentially, injury.

Try landing on the ball of your foot “for five minutes at first at the end of a run,” Mr. Daoud suggests. Work up to longer periods of forefoot landings as your body adjusts and only if you do not notice significant, continuing soreness.

In his own case, Mr. Daoud now runs consistently with a forefoot landing style, but the transition was not seamless. “I broke a metatarsal while running my first marathon after transitioning a bit too quickly and expecting a bit too much from my body too soon,” he says. So fair warning to those considering making the transition to forefoot landings: “Give your body time!”

Article source: http://well.blogs.nytimes.com/2012/02/08/why-runners-get-injured/