Soccer Referees Biased Against Tall Players

In this World Cup year, when football (soccer) passions are running high, supporters might be forgiven for objecting to every decision to award a foul against their team, made by referees. But they might also have a point. Researchers at Rotterdam School of Management, Erasmus University have researched all recorded fouls in three major football competitions over seven years. They discovered an ambiguous foul is more likely to be attributed to the taller of two players.

Dr. Niels van Quaquebeke and Dr. Steffen Giessner, scientists at Rotterdam School of Management, Erasmus University began their research by transferring their insights from decision making in business into the arena of sports. Specifically, they wanted to investigate whether people consider the available information in such ambiguous foul situations in an unbiased, i.e. subconsciously unprejudiced, way.

Based on evolutionary and linguistic research which has revealed that people associate the size of others with concepts such as aggression and dominance, Van Quaquebeke and Giessner speculated that ambiguous fouls are more likely to be attributed to the taller of two involved players. Results indicate that respectively taller people are more likely to be perceived by referees (and fans!) as foul perpetrators and their respectively smaller opponents as foul victims.

To put their assumption to a test, the scientists analysed all fouls recorded by Impire AG in seven seasons of UEFA Champions League (32,142 fouls) and German Bundesliga (85,262 fouls), the last three FIFA World Cups (6,440 fouls) as well as data from two additional perceptual experiments with football fans. For all seasons, leagues, and data collection methods, their analyses revealed the same picture confirming their initial assumption: taller people are indeed more often held accountable for fouls than shorter ones -- even when no actual foul was committed.

An article based on their research will be published in the Journal of Sport & Exercise Psychology in February 2010.

Van Quaquebeke said, "We chose football as the context of our studies because the sport often yields ambiguous foul situations in which it is difficult to determine the perpetrator. In such situations, people must rely on their 'instincts' to make a call, which should increase the use and thus the detectability of a player's height as an additional decision cue. Furthermore, the use of referee assistance technology and adequate referee training is frequently debated in association football. Thus, by providing scientific insights on potential biases in refereeing, our work might help officials weigh the options."

Both researchers say, however, that it is not their call how to derive conclusions for football practice.

Sources:   Erasmus University Rotterdam and "How embodied cognitions affect judgments: Height-related attribution bias in football foul calls"

Virtual Reality Lab Proves How Fly Balls Are Caught

While baseball fans still rank "The Catch" by Willie Mays in the 1954 World Series as one of the greatest baseball moments of all times, scientists see the feat as more of a puzzle: How does an outfielder get to the right place at the right time to catch a fly ball?


Thousands of fans (and hundreds of thousands of YouTube viewers) saw Mays turn his back on a fly ball, race to the center field fence and catch the ball over his shoulder, seemingly a precise prediction of a fly ball's path that led his team to victory. According to a recent article in the Journal of Vision ("Catching Flyballs in Virtual Reality: A Critical Test of the Outfielder Problem"), the "outfielder problem" represents the definitive question of visual-motor control. How does the brain use visual information to guide action?

To test three theories that might explain an outfielder's ability to catch a fly ball, researcher Philip Fink, PhD, from Massey University in New Zealand and Patrick Foo, PhD, from the University of North Carolina at Ashville programmed Brown University's virtual reality lab, the VENLab, to produce realistic balls and simulate catches. The team then lobbed virtual fly balls to a dozen experienced ball players.

"The three existing theories all predict the same thing: successful catches with very similar behavior," said Brown researcher William Warren, PhD. "We realized that we could pull them apart by using virtual reality to create physically impossible fly ball trajectories."

Warren said their results support the idea that the ball players do not necessarily predict a ball's landing point based on the first part of its flight, a theory described as trajectory prediction. "Rather than predicting the landing point, the fielder might continuously track the visual motion of the ball, letting it lead him to the right place at the right time," Warren said.

Because the researchers were able to use the virtual reality lab to perturb the balls' vertical motion in ways that would not happen in reality, they were able to isolate different characteristics of each theory. The subjects tended to adjust their forward-backward movements depending on the perceived elevation angle of the incoming ball, and separately move from side to side to keep the ball at a constant bearing, consistent with the theory of optical acceleration cancellation (OAC). The third theory, linear optical trajectory (LOT), predicted that the outfielder will run in a direction that makes the visual image of the ball appear to travel in a straight line, adjusting both forward-backward and side-to-side movements together.

Fink said these results focus on the visual information a ball player receives, and that future studies could bring in other variables, such as the effect of the batter's movements or sound.
"As a first step we chose to concentrate on what seemed likely to be the most important factor," Fink said. "Fielders might also use information such as the batter's swing or the sound of the bat hitting the ball to help guide their movements."

Sources:  Catching fly balls in virtual reality: A critical test of the outfielder problem and Association for Research in Vision and Ophthalmology

Boomer Brains Need Exercise

Moderate physical activity performed in midlife or later appears to be associated with a reduced risk of mild cognitive impairment, whereas a six-month high-intensity aerobic exercise program may improve cognitive function in individuals who already have the condition, according to two reports in the January issue of Archives of Neurology.

Mild cognitive impairment is an intermediate state between the normal thinking, learning and memory changes that occur with age and dementia, according to background information in one of the articles. Each year, 10 percent to 15 percent of individuals with mild cognitive impairment will develop dementia, as compared with 1 percent to 2 percent of the general population. Previous studies in animals and humans have suggested that exercise may improve cognitive function.

In one article, Laura D. Baker, Ph.D., of the University of Washington and Veterans Affairs Puget Sound Health Care System, Seattle, and colleagues report the results of a randomized, controlled clinical trial involving 33 adults with mild cognitive impairment (17 women, average age 70). A group of 23 were randomly assigned to an aerobic exercise group and exercised at high intensity levels under the supervision of a trainer for 45 to 60 minutes per day, four days per week. The control group of 10 individuals performed supervised stretching exercises according to the same schedule but kept their heart rate low. Fitness testing, body fat analysis, blood tests of metabolic markers and cognitive functions were assessed before, during and after the six-month trial.

A total of 29 participants completed the study. Overall, the patients in the high-intensity aerobic exercise group experienced improved cognitive function compared with those in the control group. These effects were more pronounced in women than in men, despite similar increases in fitness. The sex differences may be related to the metabolic effects of exercise, as changes to the body's use and production of insulin, glucose and the stress hormone cortisol differed in men and women.

"Aerobic exercise is a cost-effective practice that is associated with numerous physical benefits. The results of this study suggest that exercise also provides a cognitive benefit for some adults with mild cognitive impairment," the authors conclude. "Six months of a behavioral intervention involving regular intervals of increased heart rate was sufficient to improve cognitive performance for an at-risk group without the cost and adverse effects associated with most pharmaceutical therapies."

In another report, Yonas E. Geda, M.D., M.Sc., and colleagues at Mayo Clinic, Rochester, Minn., studied 1,324 individuals without dementia who were part of the Mayo Clinic Study of Aging. Participants completed a physical exercise questionnaire between 2006 and 2008. They were then assessed by an expert consensus panel, who classified each as having normal cognition or mild cognitive impairment.

A total of 198 participants (median or midpoint age, 83 years) were determined to have mild cognitive impairment and 1,126 (median age 80) had normal cognition. Those who reported performing moderate exercise—such as brisk walking, aerobics, yoga, strength training or swimming—during midlife or late life were less likely to have mild cognitive impairment. Midlife moderate exercise was associated with 39 percent reduction in the odds of developing the condition, and moderate exercise in late life was associated with a 32 percent reduction. The findings were consistent among men and women.

Light exercise (such as bowling, slow dancing or golfing with a cart) or vigorous exercise (including jogging, skiing and racquetball) were not independently associated with reduced risk for mild cognitive impairment.

Physical exercise may protect against mild cognitive impairment via the production of nerve-protecting compounds, greater blood flow to the brain, improved development and survival of neurons and the decreased risk of heart and blood vessel diseases, the authors note. "A second possibility is that physical exercise may be a marker for a healthy lifestyle," they write. "A subject who engages in regular physical exercise may also show the same type of discipline in dietary habits, accident prevention, adherence to preventive intervention, compliance with medical care and similar health-promoting behaviors."

Future study is needed to confirm whether exercise is associated with the decreased risk of mild cognitive impairment and provide additional information on cause and effect relationships, they conclude.

Sources:  JAMA and Archives Journals, Physical Exercise, Aging, and Mild Cognitive Impairment: A Population-Based Study  and Effects of Aerobic Exercise on Mild Cognitive Impairment: A Controlled Trial.

Ending The Myth Of The Dumb Jock

In the first study to demonstrate a clear positive association between adolescent fitness and adult cognitive performance, Nancy Pedersen of the University of Southern California and colleagues in Sweden find that better cardiovascular health among teenage boys correlates to higher scores on a range of intelligence tests – and more education and income later in life.

"During early adolescence and adulthood, the central nervous system displays considerable plasticity," said Pedersen, research professor of psychology at the USC College of Letters, Arts & Sciences. "Yet, the effect of exercise on cognition remains poorly understood."

Pedersen, lead author Maria Åberg of the University of Gothenburg and the research team looked at data for all 1.2 million Swedish men born between 1950 and 1976 who enlisted for mandatory military service at the age of 18.

In every measure of cognitive functioning they analyzed – from verbal ability to logical performance to geometric perception to mechanical skills – average test scores increased according to aerobic fitness.

However, scores on intelligence tests did not increase along with muscle strength, the researchers found.

"Positive associations with intelligence scores were restricted to cardiovascular fitness, not muscular strength," Pedersen explained, "supporting the notion that aerobic exercise improved cognition through the circulatory system influencing brain plasticity."

The results of the study – in the current issue of PNAS Early Edition – also show the importance of getting healthier between the ages of 15 and 18 while the brain is still changing.

Boys who improved their cardiovascular health between ages 15 to 18 exhibited significantly greater intelligence scores than those who became less healthy over the same time period. Over a longer term, boys who were most fit at the age of 18 were more likely to go to college than their less fit counterparts.

"Direct causality cannot be established. However, the fact that we demonstrated associations between cognition and cardiovascular fitness but not muscle strength . . . and the longitudinal prediction by cardiovascular fitness on subsequent academic achievement, speak in favor of a cardiovascular effect on brain function," Pedersen said.

In their sample, the researchers looked at 260,000 full-sibling pairs, 3,000 sets of twins, and more than 1,400 sets of identical twins. Having relatives enabled the research team to evaluate whether the results might reflect shared family environments or genetic influences.

Even among identical twin pairs, the link between cardiovascular health and intelligence remained strong, according to the study. Thus, the results are not a reflection of genetic influences on cardiovascular health and intelligence. Rather, the twin results give further support to the likelihood that there is indeed a causal relationship, Pedersen explained.

"The results provide scientific support for educational policies to maintain or increase physical education in school curricula," Pedersen said. "Physical exercise should be an important instrument for public health initiatives to optimize cognitive performance, as well as disease prevention at the society level."

Source: University of Southern California

The Fastest Man On No Legs

In an ironic twist, Oscar Pistorius' disability has now been shown to be an unfair advantage. The South African sprinter, who races with two prosthetic lower legs, has been the subject of a see-saw legal battle trying to determine if his carbon fiber, crescent-shaped manufactured legs give him an unfair advantage.

Now, two sports scientists have published new research showing that the legs, known as "Cheetahs," make him 15-20 percent faster, equal to 10 seconds over a 400 meter race, then he otherwise would be with natural legs.

In 2008, the Court of Arbitration for Sport (CAS) overturned a competition ban placed on Pistorius from the International Association of Athletics Federations (IAAF), track and field's governing body. Seven scientists produced research that refuted the IAAF's contentions and Pistorius was cleared in time to try for a spot on the Beijing Olympic squad. He just missed making that team by .7 seconds, but is now training for the 2012 London games. He did go on the win three gold medals in the 2008 Paralympics.

Pistorius, known as the Blade Runner, was born without fibula bones in his lower legs, resulting in a double amputation at the age of 11 months. At age 18, he won the 200m race at the 2004 Summer Paralympics, followed by a gold medal in the 2005 South African championships against able-bodied competitors.

Of course, when the discussion is about steroids, blood doping or even corked bats, the athlete becomes the villian. For the "fastest man on no legs," as Pistorius is often called, there are mixed opinions, ranging from those that champion the rights and progress of disabled athletes to those that want to preserve the perceived "level playing field" and integrity of the sport.

Supporting the CAS appeal, seven scientists showed that the IAAF's research (which held that Pistorius should not compete) was not valid. However, according to two of the scientists, Peter Weyand of Southern Methodist University in Dallas and Matthew Bundle of the University of Wyoming, they were careful not to imply that there was no advantage. "We are pleased to finally be able to go public with conclusions that the publishing process has required us to keep confidential until now. We recognized that the blades provide a major advantage as soon as we analyzed the critical data more than a year and a half ago," said Weyand and Bundle in a statement.

They explain that all of the group's research did not become public at the CAS hearing because, first, the CAS only asked them to refute the earlier research based on different logic and, second, the long timeline of the peer-review process of academic research just now made it possible to publish.

Specifically, what Weyand and Bundle found was that the lightweight blades weigh less than half of what a comparable human lower leg would, allowing Pistorius to swing his leg 15.7 percent faster than the average of five former 100m world record holders. They used high-speed motion cameras to compare leg speed and gait. "Even in comparison to those male sprinters with the most extreme adaptations for speed in recorded human history, Oscar Pistorius has limb repositioning times that are literally off the charts," Bundle said. "Usain Bolt is considered somewhat freakish because he outruns his opponents by 2-4 percent. At top speed, Oscar Pistorius repositions his limbs 15 percent more rapidly than six of the most recent world record holders in the 100 meter dash, including Usain Bolt."

In addition, because of how the Cheetahs, from Icelandic manufacturer Ossur, position his upper body, he can leave each "foot" on the ground longer, generating more force with each stride. "He repositions his limbs so fast that he doesn't need to get his body back up into the air so high like other sprinters, and that lowers the force he needs to generate," Weyand told Sports Illustrated. "The muscular forces he has to generate are less than half of what an intact sprinter has to generate to go the same speed."

Their research was part of a Point-Counterpoint feature in the current online edition of the Journal of Applied Physiology. In the Counterpoint reply, led by Hugh Herr of MIT, the remaining five scientists contend that studying just one double amputee does not provide enough evidence that the Cheetah legs will consistently provide an advantage. "The notion that lightweight prostheses are the only reason for Pistorius' rapid swing times ignores that he has had many years to train and adapt his neuromuscular system to using prostheses," the authors write.

The published research should not cause the CAS to reconsider and, as of now, Pistorius is still eligible to compete for a spot in London. He seems to be keeping all of this debate in perspective, "When people ask me what it's like having artificial legs, I reply, 'I don't know. What's it like having real legs?'" He adds, "Some people view themselves as disabled because they have one or two disabilities. But what about the millions and millions of abilities they have?"

Running To The Right Beat

With the Fall marathon season in full swing, thousands of runners are gearing up for the big day.  Just as important as their broken-in shoes and heart rate monitor is their source of motivation, inspiration and distraction: their tunes.

Running with music has become so common that the two biggest names in both industries, Nike and Apple, have been joined at the hip with the Nike + iPod combination. So, what is it about music and running, or any exercise, that feels so right?

Several recent studies try to chase down the connection between our ears and our feet.

For the last 20 years, Costas Karageorghis, a sports psychologist at Britain’s Brunel University, has been setting the research pace for understanding our need to groove and move.

In addition to his lab research, Karageorghis has helped create a half marathon in London that tries to find the perfect music mix of live bands based on his research of human reaction to rhythm. The second annual "Run to the Beat" event was held a few weeks ago with 9,000 laboratory rats, er, runners either enjoying the live music or listening to their own mix of tunes on their MP3.  Karageorghis even offered a scientific selection of songs based on his findings.

According to Kargeorghis, there are four factors that contribute to a song's motivational qualities: rhythm response, musicality, cultural impact and association.

The first two are known as "internal" factors as they relate to the music's structure while the second two are "external" factors that reflect how we interpret the music. Rhythm response is tied to the beats per minute (bpm) of the song and how well it matches either the cadence or the heartbeat of the runner. A song's structure such as its melody and harmony contribute to its musicality. The external factors consider our musical background and the preferences we have for a certain genre of music and what we have learned to associate with certain songs and artists.

Picking the right music can have several benefits.

Syncing beats per minute with an exercise pace increases your efficiency. In a recent study, subjects who cycled in time to music found that they required 7 percent less oxygen to do the same work when compared to music playing in the background. Music can also help block out the little voice in your brain telling you its time to quit. Research shows that this dissociation effect results in a 10 percent reduction in perceived effort during treadmill running at a moderate intensity.

In the current study, published in the Journal of Sport and Exercise Psychology, 30 subjects synchronised their pace to the tempo of the music which was 125 bpm. Before the experiment, a pool of music was rated using a questionnaire tool (the Brunel Music Rating Inventory) which then selected the most motivational pieces for the treadmill test. The subjects were given a choice of either pop or rock music.

When compared to a no-music control, the motivational synchronised music led to a 15 percent improvement in endurance.

"The synchronous application of music resulted in much higher endurance while the motivational qualities of the music impacted significantly on the interpretation of fatigue symptoms right up to the point of voluntary exhaustion," Karageorghis reported.

Matching the beats per minute of our music with our exercise heart rate also takes an interesting non-linear path, according to research.

Karageorghis found that when our hearts are performing at between 30 and 70 percent of maximum, we prefer a somewhat linear increase from 90 to 120 bpm. However, when we reach our anaerobic threshold between 70 and 80 percent of maximum, we prefer a jump in rhythm from 120 to 150 bpm. Above 80 percent of maximum heart rate, a plateau is reached where even faster music is not preferred.

Another new study by researchers from Liverpool John Moores University, and detailed online in the Scandinavian Journal of Medicine & Science in Sports, looked at the tempo angle differently. Instead of a mix of different songs at different tempos, they asked a group of cyclists to pedal to the same song over three different trials.

What the subjects did not know is that the researchers first played the song at normal speed, but then increased or decreased the speed of the same song by 10 percent. The small change was not enough to be noticed, but it did have an effect on performance.

Speeding up the music program increased distance covered/unit time, power and pedal cadence by 2.1 percent, 3.5 percent and 0.7 percent, respectively. Slowing the program produced falls of 3.8 percent, 9.8 percent and 5.9 percent. The researchers concluded that we increase or decrease our work effort and pace to match the tempo of our music.

Finding the right beat has now become even easier with a couple of cool software plug-in tools, Cadence or Tangerine.  Cadence is an iPhone/iPod Touch app, while Tangerine is Mac only. By integrating with your iTunes library, they can build a custom playlist based on the BPM range you provide, while arranging the songs in several different tempo shapes including warm-ups and warm-downs. With the right mix, your brain and feet will be in perfect harmony.

I Run, Therefore I Drink?

Here’s a question for your buddies at the next golf outing or bowling league night: Are we more active because we drink more or do we drink more because we’re more active? Recent research showed that there is a correlation between the two, but could not offer a solid reason.

Either way, another study claims the combination of moderate alcohol use and exercise will help our hearts more than just choosing one over the other.

Michael French, a health economics professor at the University of Miami, and his colleagues dug into data from the 2005 Behavioral Risk Factor Surveillance System, a yearly telephone survey of roughly 230,000 Americans, and found a surprisingly strong positive correlation between the levels of alcohol intake and exercise.  For both men and women, those who drank at least some alcohol exercised 7.2 minutes more per week than non-drinkers.

While that may not seem like much, the study showed that the more booze, the more minutes spent sweating. Light, moderate, and heavy drinkers worked out 5.7, 10.1 and 19.9 minutes more per week, respectively. Also, drinking resulted in a 10.1 percent increase in the probability of vigorous physical activity.

Now, that doesn’t mean that these folks were drinking while exercising, nor that it was necessarily good for them to engange in more than light drinking. Instead, French and his team, who have studied many facets of alcohol abuse and its triggers, are trying to make sense of this correlation that seems too strong to ignore. It seems counterintuitive to traditional views that if people engage in one unhealthy behavior, like excessive drinking, that they will most likely engage in other unhealthy behaviors, like physical inactivity.

French suggests that heavy alcohol use may be masked by the appearance of a healthy lifestyle and cautions physicians not to jump to conclusions.

“For example, taking into account only the patients’ levels of physical activity and perhaps diet would overlook potential alcohol use problems that could be detected and treated,” French writes. “Physically active individuals who engage in problematic drinking are often ‘‘healthy looking,’’ because alcohol use consequences are sometimes delayed.”

The study appears in the September/October issue of American Journal of Health Promotion.

Maybe we exercise more because we know how many calories those beers and mixers are adding to our waistlines. Even so, Danish researchers found that we’re still better off combining moderate alcohol consumption with exercise.

Morten Gronbaek, epidemiologist with Denmark’s National Institute of Public Health, and his team surveyed 12,000 people over a 20-year period to determine the cardiovascular effects of alcohol use and exercise. They divided the population into four groups: those who did not drink or exercise; those who had both moderate levels of alcohol use and exercise; and those who either just drank or just exercised at moderate levels.

The group with the highest risk of fatal ischaemic heart disease, a form of heart disease characterized by a reduced blood supply to the heart, were the non-drinking, non-exercisers. Choosing either moderate drinking or moderate exercise provided a 30 percent decrease in risk factors. However, drinking and exercising, (not necessarily at the same time), showed a 50 percent lower risk.

Their findings were detailed in the European Heart Journal.

“Being both physically active and drinking a moderate amount of alcohol is important for lowering the risk of both fatal IHD and death from all causes,” Gronbaek concluded.  Of course, the key is moderation, defined in the study as one drink per day for women and two per day for men. Also, Gronbaek warns that there is no heart benefit until a certain age.

“You wouldn’t advise everyone to drink,” he said. “You shouldn’t even think about doing it until age 45 or 50. There’s absolutely no proof of a preventative and protective effect before age 45.”

How To See A 130 MPH Tennis Serve

For most of us mere mortals, if an object was coming at us at 120-150 mph, we would be lucky to just get out of the way. Players in this week's U.S. Open tennis tournament not only see the ball coming at them with such speed, but plan where they want to place their return shot and swing their racquet in time to make contact. At 125 mph from 78 feet away, that gives them a little less than a half second to accomplish the task.

How do they do it? Well, they're better than you and I, for one. But science has some more specific answers to offer.

Swiss researchers have concluded that expert tennis players, like their own Roger Federer, have an advantage in certain visual perception skills, while UK scientists have shown how trained animals — and presumably humans — can rely on a superior internal model of motion to predict the path of a fast moving object.

For any sport that involves a moving object, athletes must learn the three levels of response for interceptive timing tasks. 

• First, there is a basic reaction, also known as optometric reaction (in other words, see it and get out of the way).

• Next, there is a perceptual reaction, meaning you actually can identify the object coming at you and can put it in some context (for example: That is a tennis ball coming at you and not a bird swooping out of the sky).

• Finally, there is a cognitive reaction, meaning you know what is coming at you and you have a plan of what to do with it (return the ball with top-spin down the right line).

This cognitive skill is usually sport-specific and learned over years of tactical training. Obviously, professional tennis players are at the expert cognitive stage and have a plan for most shots.

But, in order to reach that cognitive stage, they first need to have excellent optometric and perceptual skills.

Leila Overney and her team at the Brain Mind Institute of Ecole Polytechnique Federale de Lausanne (EPFL) studied whether expert tennis players have better visual perception abilities than other athletes and non-tennis players. Typically, motor skill research compares experts to non-experts and tries to deduce what the experts are doing differently to excel.

They carried out seven visual tests, covering a wide range of perceptual functions including motion and temporal processing, object detection and attention, each requiring the participants to push buttons based on their responses to the computer-based tasks and each related to a particular aspect of visual perception.

In this study, which was detailed in the journal PLOS One, Overney wanted to see if the perceptual skills of the tennis players were not only more advanced than non-tennis players but also other athletes of a similar fitness level, (in this case triathletes), to eliminate any benefits of just being in top physical shape.  To eliminate the cognitive knowledge difference between the groups, she used seven non-sport specific visual tests which measured different forms of perception including motion and temporal processing, object detection and attention. The participants watched the objects on computer screens and pushed buttons per the specific test instructions.

The tennis players showed significant advantages in the speed discrimination and motion detection tests, while they were no better in the other categories.

"Our results suggest that speed processing and temporal processing is often faster and more accurate in tennis players," Overney writes. They even scored better then their peers, the triathletes. "This is precisely why we added the group of triathletes as controls because they train as hard as tennis players but have lower visual processing demands in their sport."

Still, are the tennis players really just relying on their visual advantage when given that half second to react? Have their years of practice created an internal cognitive model that anticipates and predicts the path of an object?

Nadia Cerminara worked on that question. Cerminara, of the University of Bristol (UK), designed an experiment that taught household cats to reach with their paw at a moving target. If they successfully touched the target, they received a food reward.

After training the cats to be successful, she recorded their neuronal activity in their lateral cerebellum. Then, she measured the activity again but would block the vision of the cats for 200-300 milliseconds while performing the task. Despite the lapse in visual information, the neuron firing activity remained the same as before. Cerminara concluded that an internal model had been used to bridge the gap and provide a prediction of where the object was headed.

The study was published in the Journal of Physiology.

So, when faced with a blistering serve, science suggests that players like Federer not only rely on their superior perceptual skills, but also have created an even faster internal simulation of a ball's flight that can help position them for a winning return.

Of course, you may want to avoid the world's fastest server, Andy Roddick, especially when he's upset from a bad line call (see video). :-)

Running Addicts Need Their Fix

Just as there is the endorphin rush of a "runner's high," there can also be the valley of despair when something prevents avid runners from getting their daily fix of miles.

Now, researchers at Tufts University may have confirmed this addiction by showing that an intense running regimen in rats can release brain chemicals that mimic the same sense of euphoria as opiate use. They propose that moderate exercise could be a "substitute drug" for human heroin and morphine addicts.

Given all of the benefits of exercise, many people commit to an active running routine. Somewhere during a longer, more intense run when stored glycogen is depleted, the pituitary gland and the hypothalamus release endorphins that can provide that "second wind" that keeps a runner going.

This sense of being able to run all day is similar to the pain-relieving state that opiates provide, scientists have known. So a team led by Robin Kanarek, professor of psychology at Tufts University, wondered whether they could also produce similar withdrawal symptoms, which would indicate that intense running and opiate abuse have a similar biochemical effect.

Running rodents
The team divided 44 male rats and 40 female rats into four groups. One group was housed inside an exercise wheel, and another group had none. Each group was divided again, either allowing access to food for only one hour per day or for 24 hours per day. Though tests on humans would be needed to confirm this research, rodents are typically good analogues to illuminate how the human body works.
The rodents existed in these environments for several weeks. Finally, all groups were given Naloxone, a drug used to counteract an opiate overdose and produce immediate withdrawal symptoms.

The active rats displayed a significantly higher level of withdrawal symptoms than the inactive rats. Also, the active rats that were only allowed food for one hour per day exercised the most and showed the most intense reaction to Naloxone. This scenario mimics the actions of humans suffering from anorexia athletica, also known as hypergymnasia, that causes an obsession not only with weight but also with continuous exercise to lose weight.

"Exercise, like drugs of abuse, leads to the release of neurotransmitters such as endorphins and dopamine, which are involved with a sense of reward," Kanarek said. "As with food intake and other parts of life, moderation seems to be the key. Exercise, as long as it doesn't interfere with other aspects of one's life, is a good thing with respect to both physical and mental health."

The study appears in the August issue of Behavioral Neuroscience, published by the American Psychological Association.

Treatment ideas
Kanarek hopes to use these results to design treatment programs for heroin and morphine addicts that substitute the all-natural high of exercise in place of the drugs.  "These findings, in conjunction with results of studies demonstrating that intake of drugs of abuse and running activates the endogenous opioid and dopamine reward systems, suggest that it might be possible to substitute drug-taking behavior with naturally rewarding behavior," she writes.

She also wants to do further research on understanding the neurophysiology of extreme eating and exercise disorders. "The high comorbidity of drug abuse and eating disorders provides further evidence of a common neurobiological basis for these disorders," Kanarek concludes.

The Physiology Of Speed

Usain Bolt, the triple Olympic gold medal sprinter from Jamaica, predicted last week that he could break his own world record of 9.69 seconds in the 100 meter sprint with a time as low as 9.54 seconds.  (8/15 update: he came very close running a 9.58 at the World Championships in Berlin.)

He claimed his coach told him its possible, so he believes him. His coach, Glen Mills, may have just finished reading some new research coming out of Duke University that showed sprinters and swimmers who are taller, heavier but more slender are the ones breaking world records.

At first glance, it may not make sense that bigger athletes would be faster. However, Jordan Charles, a recent engineering grad at Duke, plotted all of the world record holders in the 100 meter sprint and the 100 meter swim since 1900 against their height, weight and a measurement he called "slenderness."

World record sprinters have gained an average of 6.4 inches in height since 1900, while champion swimmers have shot up 4.5 inches, compared to the mere mortal average height gain of 1.9 inches.
During the same time, about 7/10 of a second have been shaved off of the 100-meter sprint while over 14 seconds have come off the 100-meter swim record.

What's going on
Charles applied the "constructal theory" he learned from his mentor Adrian Bejan, a mechanical engineering professor at Duke, that describes how objects move through their environment.

"Anything that moves, or anything that flows, must evolve so that it flows more and more easily," Bejan said. "Nature wants to find a smoother path, to flow more easily, to find a path with less resistance," he said. "The animal design never gets there, but it tries to be the least imperfect that it can be."

Their research is reported in the current online edition of the Journal of Experimental Biology.

For locomotion, a human needs to overcome two forces, gravity and friction. First, an athlete would need to lift his foot off the ground or keep his body at the water line without sinking. Second, air resistance for the sprinter and water resistance for the swimmer will limit speed.

So, the first step is actually weight lifting, which a bigger, stronger athlete will excel at. The second step is to move through the space with the least friction, which emphasizes the new slenderness factor.

By comparing height with a calculated "width" of the athlete, slenderness is a measurement of mass spread out over a long frame. The athlete that can build on more muscle mass over a aerodynamic frame will have the advantage.

The numbers
In swimming, legendary Hawaiian champion Duke Kahanamoku set the world record in 1912 with a time of 61.6 seconds with a calculated slenderness of 7.88. Some 96 years later, Eamon Sullivan lowered the world mark to 47.05 seconds at a slenderness factor of 8.29.

As the athletes’ slenderness factor has risen over the years, the winning times have dropped.  In 1929, Eddie Tolan's world-record 100 meter sprint of 10.4 seconds was achieved with a slenderness factor of 7.61. When Usain Bolt ran 9.69 seconds in the 2008 Olympics, his slenderness was also 8.29 while also being the tallest champion in history at 6-feet 5-inches.

“The trends revealed by our analysis suggest that speed records will continue to be dominated by heavier and taller athletes,” said Charles. “We believe that this is due to the constructal rules of animal locomotion and not the contemporary increase in the average size of humans.”

So, how fast did the original Olympians run? Charles used an anthropology finding for Greek and Roman body mass and plugged it into his formula.

“In antiquity, body weights were roughly 70 percent of what they are today,” Charles said. “Using our theory, a 100-meter dash that is won in 13 seconds would have taken about 14 seconds back then.”
Bolt puts his prediction to the test next month at the track and field world championships in Berlin. One of his main competitors is Asafa Powell, the previous world record holder, who is shorter and has a slenderness factor of 7.85. My money is on the Lightning Bolt.

Cyclists' Sore Seats Signal Serious Symptoms

For any guy who has endured more than thirty minutes on a road bicycle seat, there is usually some concern over the strange numbness that occurs in places that should not go numb. Well, a new study has some good and bad news.

Spanish researchers have found that active male cyclists have lower quality sperm to the point of infertility risk. Among other things, they blame the painful "function over form" design of the wedge bicycle seat.

The good news is that unless you're training to be in the next Tour de France with Lance Armstrong, your time on the saddle shouldn't do any long-term damage.

A team led by professor Diana Vaamonde, from the University of Cordoba Medical School, tracked the workout regimen of 15 Spanish triathletes, with an average age of 33 who had been training for at least eight years, while also monitoring their sperm morphology.

For those in the test group that covered more than 180 miles per week on their bikes, the percentage of normal looking sperm dropped from a group average of 10 percent to 4 percent, a rate where infertility problems begin. Increased swimming or running did not affect sperm quality.

"We found a statistically adverse correlation between sperm morphology and the volume of cycling training undertaken per week," Vaamonde said. "We believe that all the factors inherent in this sports activity, especially with regards to the cycling part, may affect sperm quality," she added. "Moreover, we think that normal physiological homeostasis – the body’s ability to regulate its own environment – may become irreversibly altered, therefore resulting in complex anomalies."

Vaamonde cited three possible reasons for the results: the

increased heat during exercise

, the friction and pressure against the seat causing microtrauma on the testes, and the overall rigor of intense exercise.

The study was released last week in Amsterdam at the annual conference of the European Society of Human Reproduction and Embryology (ESHRE).

The Spanish researchers were following up on research from 2002 that showed similar results for mountain bikers. In that study, Austrian researcher Ferdinand Frauscher tested 40 active (two hours per day) mountain bikers with 30 non-bikers. He found that the bikers had about half the sperm count of the non-bikers. Frauscher explained (as only a medical doctor can) the possible reasons: "The exact causes for the decreased sperm motility are unclear. We believe that repeated mechanical trauma to the testicles results in some degree of vascular damage, and may thereby cause a reduction in sperm motility." Ouch.

For casual bike riders, the risk is still quite low. Allan Pacey, senior lecturer in andrology at the University of Sheffield, told BBC News, "It is important to stress that even if the association between cycling and poor sperm morphology is correct, men training for triathlons are spending much more time in the saddle than the average social cycler or someone who might cycle to and from work."

For those that are still not okay with the "saddle sores," there are always the anatomically correct seats and the padded biker shorts, not to mention recumbent bikes. Beyond that, maybe a nice jog would be better.

Kids' Baseball Injuries Down But Some Still Play "Until It Hurts"

At a recent baseball game, the 12-year-old second baseman on my son's team had a ground ball take a nasty hop, hitting him just next to his right eye. He was down on the field for several minutes and was later diagnosed at the hospital with a concussion.

Thankfully, acute baseball injuries like this are on the decline, according to a new report. However, several leading physicians say overuse injuries of young players caused by too much baseball show no signs of slowing down.

Our unlucky infielder's hospital injury report may become part of a national database called the National Electronic Injury Surveillance System (NEISS), part of the U.S. Consumer Product Safety Commission. It monitors 98 hospitals across the country for reports on all types of injuries.

Bradley Lawson, Dawn Comstock and Gary Smith of Ohio State University filtered this data to find just baseball-related injuries to kids under 18 from 1994-2006.

During that period, they found that more than 1.5 million young players were treated in hospital emergency rooms, with the most common injury being, you guessed it, being hit by the ball, and typically in the face.

The good news is that the annual number of baseball injuries has decreased by 24.9 percent over those 13 years. The researchers credit the decline to the increased use of protective equipment.

"Safety equipment such as age-appropriate breakaway bases, helmets with properly-fitted face shields, mouth guards and reduced-impact safety baseballs have all been shown to reduce injuries," Smith said. "As more youth leagues, coaches and parents ensure the use of these types of safety equipment in both practices and games, the number of baseball-related injuries should continue to decrease. Mouth guards, in particular, should be more widely used in youth baseball."

Their research is detailed in the latest edition of the journal Pediatrics.

The bad news is ...
 

While accident-related injuries are down, preventable injuries from overuse still seem to be a problem, according to author Mark Hyman. In his recent book, "Until It Hurts," Hyman admits his own mistakes in pressuring his 14-year-old son to continue pitching with a sore arm, causing further injury.

Surprised by his own unwillingness to listen to reason, Hyman, a long-time journalist, researched the growing trend of high-pressure parents pushing their young athletes too far, too fast.

"Many of the physicians I spoke with told me of a spike in overuse injuries they had witnessed," Hyman told Livescience. "As youth sports become increasingly competitive — climbing a ladder to elite teams, college scholarships, parental prestige and so on — children are engaging in a range of risky behaviors."

One expert he consulted was Dr. Lyle Micheli, founder of one of the country's first pediatric sports medicine clinics at Children's Hospital in Boston. Micheli estimates that 75 percent of the young patients he sees are suffering from some sort of overuse injury, versus 20 percent back in the 1990s.

"As a medical society, we've been pretty ineffective dealing with this," Micheli said. "Nothing seems to be working."

Young surgeries

In severe overuse cases for baseball pitchers, the end result may be ulnar collateral ligament surgery, better known as "Tommy John" surgery. Dr. James Andrews, known for performing this surgery on many professional players, has noticed an alarming trend in his practice. Andrews told The Oregonian last month that more than one-quarter of his 853 patients in the past six years were at the high school level or younger, including one 7-year-old.

Last spring, Andrews and his colleagues conducted a study comparing 95 high-school pitchers who required surgical repair of either their elbow or shoulder with 45 pitchers that did not suffer injury.

They found that those who pitched for more than eight months per year were 500 percent more likely to be injured, while those who pitched more than 80 pitches per game increased their injury risk by 400 percent.  Pitchers who continued pitching despite having arm fatigue were an incredible 3,600 percent more likely to do serious damage to their arm.

Hyman encourages parents to keep youth sports in perspective. "I think that, generally, parents view sports as a healthy and wholesome activity. That's a positive. But, we live in hyper-competitive culture, and parents like to see their kids competing," he said. "It's not only sports. It's ballet and violin and SAT scores and a host of other things.  It's in our DNA."

Please visit my other sports science articles at Livescience.com.

NASCAR Fans Drive Faster

If you plan on watching your favorite NASCAR driver this weekend, you may want to have your designated driver take you home. Not only should he be sober, but he also should have no interest in motor sports.

According to Australian researchers, being a race fan makes you more likely to not only speed in your own car but also to see little wrong with it.

Several factors have been found to influence a driver's attitude towards speeding and aggressive driving, including age, gender and what psychologists call "sensation seeking propensity." This thrill-seeking behavior may also be a result of a driver's environment.

Paul Tranter and James Warn of the University of New South Wales wanted to see if following professional motor sports as a fan added to the need to be fast and furious.

Specifically, they considered whether social cognitive theory, made famous by American psychologist Albert Bandura, explained a fan's need to imitate their favorite drivers by pushing the limits on public roads.

In 2004, with illegal street racing becoming a problem on the streets of Sydney and Melbourne, Tranter and Warn focused on young drivers. In a survey of 180 males between the ages of 15 and 24, they measured interest in organized motor sports against attitudes towards safe driving and obeying traffic laws. Each driver's own violation history was also considered.

Results showed an interest in organized racing had a direct effect on not only involvement in illegal racing but also higher violations and riskier attitudes towards traffic laws. Maybe young fans figured that if Danica Patrick can maneuver a 650 horsepower beast around an oval track for a few hours, they should be able push their modified Civic to 100 mph.

Even though the researchers were careful to control for the sensation-seeking personality variable in their survey population, they still wanted to expand their study to older race fans to see if the same relationship held.

In their latest study, published in the journal Accident Analysis and Prevention, Tranter and Warn looked only at drivers 25 and older with at least 2 years driving experience. Insurance companies consider this age group a much safer population. A similar survey was distributed to residents of a small NSW town and asked for three things: their level of interest in motor sports; their attitudes toward speeding and traffic laws; and their own self-reported negative driving habits.

The strongest correlation in this group was between an interest in racing and a pro-speeding attitude. So, even among the safer, older group of fans, an intentional lead foot existed.

So, should we put restrictor plates on all cars? No, say Tranter and Warn, but maybe a more visible safety PR campaign to the masses may help.

"There remains a need to get the message out to the driving community that speed is linked to accidents, and that attitudes that condone speeding are a road safety problem," Tranter writes. He adds that another idea would be to shift a young driver's need for risk taking to other sports, (like downhill skiing or mountain biking) that have a more positive "thrill to bad outcome" ratio.

Then again, Tranter comments that the attraction expressed to him by street racers may just be, "'chicks and fast cars,' rather than a desire to engage in illegal activity."

Please visit my other sports science articles at Livescience.com.

For Kids' Health, Just Let Them Play

As usual, your Mom was right. When she told you to get outside and play, she instinctively knew that would be good for you.

Health science researchers at the University of Exeter have found that kids' natural short bursts of play energy contribute just as much to a healthy lifestyle as longer bouts of organized exercise, such as gym class.
As of 2008, 32 percent of U.S. children were overweight or obese, as measured by their body mass index. While many organized programs have studied this epidemic, the prescription remains the same: less food, more exercise.

In fact, a previous health science study of 133 children found that the physical activity of the obese children over a three-week period was 35 prcent less during school days and 65 percent less on weekends compared to the children who were within accepted healthy weight norms.

In the new study, Michelle Stone and Roger Eston of Exeter's School of Sport and Health Sciences measured the activity level of 47 boys aged between 8 and 10 over seven days using an accelerometer strapped to each boy's hip (similar to the one inside your iPhone or Wii controller that senses motion).
The key was to find a model that would record the shortest bursts of energy, sometimes less than 2 seconds. As any boy's parents know, those spurts can happen all afternoon, whether it be chasing the dog, throwing rocks in the lake or climbing a tree.

The researchers also measured waist circumference, aerobic fitness and blood pressure of each boy. They found that even though their activity levels came in many short chunks, their health indicators were all in the normal range.

Stone explains their conclusion, "Our study suggests that physical activity is associated with health, irrespective of whether it is accumulated in short bursts or long bouts. Previous research has shown that children are more naturally inclined to engage in short bursts of running, jumping and playing with a ball, and do not tend to sustain bouts of exercise lasting five or more minutes. This is especially true for activities that are more vigorous in nature.

Their findings are in the April edition of the International Journal of Pediatric Obesity.

The researchers admit that more research is needed to measure long-term effects on health.  Establishing activity guidelines for parents and schools will help the kids plan time to move each day.

The National Football League has even started a program called NFL Play 60 that encourages kids to move for at least 60 minutes each day.  "Our players know the importance of staying healthy and it’s important that young fans also understand the value of exercise," said NFL Commissioner Roger Goodell. "Play 60 is an important tool in ensuring children get their necessary daily physical activity as recommended by health and fitness experts."

So, more recess and less physical education in our schools? Maybe, according to Stone, "If future research backs up our findings, we would do better to encourage young children to do what they do naturally, rather than trying to enforce long exercise sessions on them. This could be a useful way of improving enjoyment and sustainability of healthy physical activity levels in childhood."

Please visit my other sports science articles at Livescience.com

Thoroughbred Horse Injuries Rise But Race Times Stay Flat

Imagine trying to walk on all fours using just your big toes and your middle fingers. That is similar to what modern thoroughbred racehorses endure when racing around a track at up to 30 mph.

This weekend's Belmont Stakes will be missing one of this year's stars, Rachel Alexandra, on the precaution that she needs to rest.  Just before last month's Kentucky Derby, three top contenders, Quality Road, I Want Revenge and Square Eddie were forced out of the race due to hoof and shin injuries.

Critics claim selective breeding may be producing an unstable horse anatomy that is prone to injury. Yet, a recent study claims that it all may be for naught, as thoroughbreds may have already reached their theoretical upper limits of speed.

Running on their toes
One of out ten thoroughbreds will suffer from some orthopedic problem, including fractures, which often lead to decisions to destroy them. In the United States, for every 1,000 horses starting a race, there will be 1.5 career-ending injuries, which is almost two per day.

By breeding for speed and power, the bulk of the horse increases while the ankles and lower legs do not,according to some veterinarians.

"Anatomically speaking, they run on their toes," said Lawrence R. Soma, professor at the University of Pennsylvania School of Veterinary Medicine. "That makes them very fragile."

The pounds per square inch load that is put on their hoofs would be similar to humans walking on their middle fingers, experts say. One misstep on a soft patch of the turf can cause a break.

So they're faster, right?
Given the large sums of money spent on breeding champion racehorses and the potential health side effects, is it worth it? Are the race times getting faster thanks to these selective genetic performance filters?  The answer is no, according to Mark Denny, Professor of Biology at Stanford University.

In a recent study published in the Journal of Experimental Biology, Denny analyzed the race time records for the three U.S. Triple Crown races; the Kentucky Derby, the Preakness Stakes, and the Belmont Stakes. The plateau for similar times for the Kentucky Derby began in 1949, while the Preakness and the Belmont set their plateaus in 1971 and 1973, respectively, Denny found.

"Evidence from the Triple Crown races suggests that the process of selective breeding of thoroughbreds (as practiced in the US) is incapable of producing a substantially faster horse," Denny writes. "Despite the efforts of the breeders, speeds are not increasing, and current attempts to breed faster horses may instead be producing horses that are more fragile."

The solution
Denny also tried to predict the fastest possible time for these horses. Using statistical modeling, he found that the maximum speed of a thoroughbred would be only 0.5 to 1 percent faster than seen today.

"These results suggest that definite speed limits do indeed exist for horses and that their current speeds are very close to these predicted limits," Denny said.

One reason for the limit may be the gene pool. Today's thoroughbreds descend from a lineage of only 12-29 ancestors, with 95 percent of today's thoroughbreds tracing their paternal roots to a single stallion, The Darley Arabian.

Denny suggests that breeding from outside this line might produce the potential for improvement.

Please visit my other sports science articles at Livescience.com.

NFL Scouting Combine Not A Good Predictor of Draft Pick Success

Every April, general managers and head coaches fear that their NFL Draft selection of "can't miss" college players may end up being added to the long list of past multi-million dollar draft mistakes.
So, for last month's NFL Draft, they hope they found the right matrix of information that will reveal those players with true NFL potential. One set of criteria that seems to get more media attention every year is the scouting combine, a collection of physical and mental tests given to about 300 invited prospects.

However, university researchers have now shown the tests are not good predictors of success in the NFL.

According to ESPN, of the top 10 player selections in the last five drafts (50 players total), eight have been released or traded at least once and five are completely out of the league.

Teams are becoming less willing to gamble millions of dollars on a player who has not played a single snap in the league.

The combine event, held in Indianapolis each February, was meant to provide some common denominators to compare players. Physical tests such as the 40-yard dash, shuttle and agility runs, bench press, and the vertical jump are combined with the Wonderlic Personnel Test (WPT), a 50-question general intelligence test, to paint a profile of a player beyond his on-field resume.

Of course, teams should evaluate the whole package of game film, interviews and position-specific drills, but the combine data seems to be growing in influence. A player's stock seems to rise and fall with their performance at Indianapolis.

In fact, a 2003 Arizona State University study showed that performance at the combine was directly related to draft order, which might indicate that teams rely on these tests more than they admit.

Specific combine tests also seem to make a difference in getting drafted. Last year, University of North Carolina researchers found that there were significant performance differences between drafted and non-drafted skill players in the 40-yeard dash, the shuttle runs and the vertical jump, while drafted linemen performed better in the 40-yard dash and bench press.

But in a new study, Frank Kuzmits and Arthur Adams, professors at the University of Louisville, evaluated more than 300 quarterbacks, running backs and wide receivers drafted over six seasons from 1999-2004.

They compared the players' combine performance on seven physical tests and the WPT with measures of success in the NFL. These three skill positions were chosen as they have distinct performance statistics that can be tracked (as opposed to linemen or defensive players.)

Each position used the success metrics of draft order, salaries for years 1-3 and games played for years 1-3. In addition, QB rating, yards per carry and yards per reception were measured for quarterbacks, running backs and wide receivers, respectively.

No significant link was found between combine performance and NFL success, except between 40-yard dash times and running backs. Interestingly, even the Wonderlic aptitude test did not predict NFL achievement, even though a skill position like quarterback requires a decent amount of cognitive talent. That's not to say other psychological tests would be worthless. Kuzmits and Adams cite other studies that show a player's level of self-confidence and anxiety management to be strong clues to their future accomplishments.

Of course, not all draft picks are surrounded by great teammates and some don't even get out on the field during those first few seasons. But this research showed that good or bad performance in the combine is not related to good or bad performance on the field. So, the researchers question the value of these combine tests as a draft decision support tool.

They do see a similarity between NFL teams choosing players and companies choosing employees.
"Contemporary human resource techniques could be applied to any hiring decision, including the NFL hiring process," Kuzmits told LiveScience. "Basically, teams could develop a regression equation with various success predictors weighted (college success, combine tests and interviews, awards, psychological profile, etc.). It could be done but in the end 'art' would probably trump 'science.'"

Please visit my other sports science articles on Livescience.com

NBA Teams Win With Ethnic Diversity

When the National Basketball Association Conference Finals tip off later this week, four teams will test their level of cooperation, unselfishness and teamwork. One issue that apparently will not get in their way is diversity.

Two new studies have shown that an NBA team's level of racial or ethnic diversity does not have any significant impact on its winning percentage or its players' split-second decision making on the court. These reassuring findings on player unity contrast with a 2007 report showing same-race bias among NBA referees when making foul calls.

The demographics of the NBA have changed dramatically over the last 40 years. African-Americans make up about 76 percent of the league's players, while Latinos and Asians account for three and one percent, respectively. According to the NBA, 77 international players from 32 countries contributed just over 17 percent to team rosters. There are not only potential ethnic and cultural barriers, but also language differences that may impact a team's chemistry.

For any organization, results matter. However, few groups of co-workers have their teamwork watched, measured and analyzed to the extent of an NBA team.

Diversity measured 
Paul Sommers and Jessica Weiss of Middlebury College wanted to see if the level of an NBA team's diversity affected its ability to win. For the last three complete NBA seasons (through 2007-08), players who had at least 800 minutes of court time were divided into one of five racial or demographic groups; African-Americans, Caucasians, East Europeans, Asians, and other foreign-born players who did not play either high school or college basketball in the United States. Using the Herfindahl-Hirschman index (HHI) to measure diversity, a number was assigned to each team for each season. An index of 1.0 would indicate a completely homogeneous team, while more diverse teams would score lower (between 0 and 1).

When the HHI was regressed against each team's regular season winning percentage, no significant correlation was found. In other words, a team's diversity did not help or hurt their success on the court. As supporting evidence, the last three NBA champions, the Boston Celtics (2007-08), the San Antonio Spurs (2006-07), and the Miami Heat (2005-06), had dramatically different HHIs of 1.0, .360, and .781, respectively.

What about that language barrier? If communications suffered, then there should be passing mixups and team turnovers should rise. To find out, Sommers and Weiss divided the teams into two groups, more diverse and less diverse at the median HHI for the league. Over the three seasons, there was no significant difference in total turnovers between the two groups.

The findings were detailed in last month's Atlantic Economic Journal.

Carrying that on-court cooperation theme even further, Brigham Young researchers searched for same-race bias in NBA players when passing to their teammates. To put it bluntly, would a white player subconsciously prefer to pass to another white player if given a choice and, conversely, a black player to a black player? In an exhaustive study, Joseph Price, Lars John Lefgren and Henry Tappen dug into six seasons of NBA data to look at every assisted basket and recorded the race (noted simply as "black" or "not black") of the passer and the scorer. They also noted the other three players on the floor when the basket was made. Of course, there were numerous decision variables that the researchers had to eliminate to isolate just racial preference.

The conclusion: No same-race bias was found in the passing patterns of NBA players.  Study details are available from the Social Science Research Network as part of their working paper series.

Referees don't play fair
Joseph Price is known for his controversial paper in 2007 that concluded there is significant same-race bias shown by NBA referees. In that study, more than 600,000 officiating calls over 13 seasons were analyzed to see if white referees would call fewer fouls on white players than black players and vice versa (black referees whistling black players).

They concluded that the difference was "large enough that the probability of a team winning is noticeably affected by the racial composition of the refereeing crew assigned to the game.”

In fact, their data showed that players earned up to 4 percent fewer fouls and scored up to 2.5 percent more points on nights in which their race matches that of the refereeing crew. From a team perspective, the bias factor may change the outcome of two games out of an 82 game season. For some teams, that may be the difference that keeps them out of the playoffs.

Please visit my other sports science articles at Livescience.com

Tiger's Brain Is Bigger Than Ours

As Tiger Woods heads to Sawgrass for The Players Championship this weekend, mortal golfers wonder what's inside his head that keeps him winning. Well, chances are his brain actually has more gray matter than the average weekend duffer.

Researchers at the University of Zurich have found that expert golfers have a higher volume of the gray-colored, closely packed neuron cell bodies that are known to be involved with muscle control. The good news is that, like Tiger, golfers who start young and commit to years of practice can also grow their brains while their handicaps shrink.

Executing a good golf swing consistently is one of the hardest sport skills to master. Coordinating all of the moving body parts with the right timing requires a brain that has learned from many trial and error repetitions.

In fact, past studies have shown that the number of hours spent practicing is directly related to a golfer's handicap (a calculated number that represents recent playing ability).

Magic number
K. Anders Ericsson, a Florida State professor and the "expert on experts," has spent more than 25 years studying what it takes to become elite in any field, including sports.

The magic number that keeps recurring in Ericsson's studies is 10,000 hours of deliberate practice. If someone is willing to dedicate this amount of structured time on any skill, he has the potential to rise to the top.

Some critics argue that practice is good, but we all start with different levels of innate abilities that put some at an early advantage (i.e. the boy who is six feet tall in fourth grade) While that may be true, Ericsson does not want the rest of us to use that as an excuse. "The traditional assumption is that people come into a professional domain, have similar experiences, and the only thing that's different is their innate abilities," he said in an interview with Fast Company. "There's little evidence to support this. With the exception of some sports, no characteristic of the brain or body constrains an individual from reaching an expert level."

So, what happens to the brain after all of that practice?

In the new study, a team led by neuropsychologist Lutz Jäncke compared the brain images of 40 men divided into four groups based on their experience as golfers. They recruited ten professional golfers (with handicaps of 0), ten advanced golfers (handicaps between 1 and 14), ten average golfers (handicaps between 15 and 36) and ten volunteers who had never played golf (not even mini-golf!).

Interviews revealed the "practice makes perfect" correlation between hours of practice and lower handicaps.

Brain scans (functional Magnetic Resonance Imaging (fMRI) showed that, indeed, there were structural differences, but not in the linear pattern they imagined. While significant differences existed in total volume of gray matter between the pros and the non-players, there was little difference between the pro and the advanced groups or between the average and non-players groups.

When the researchers combined the pros and the advanced golfers into one group called "expert," and the average and non-players into a second group called "novice," a clear dividing line emerged, showing that practice produces a noticeable step up in the brain's gray matter. This jump comes somewhere between 800-3,000 practice hours.

The results were detailed last month in the online journal PLoS ONE.

Step 1: Grow the brain
Another interesting twist is that the pros reported practicing five to eight times more than the advanced group, while the advanced group practiced only twice as much as the average group.

Yet the big jump in gray matter came after golfers achieved a skill level below a 15 handicap, moving from average to advanced. This is consistent with another study in 2008 that measured gray matter volume in students learning to juggle three balls. After learning to juggle for the first time, their gray matter increased. However, once that initial concept was learned, more advanced juggling tricks did not grow more brain cells.

It's been a long time since Tiger's handicap was 15, so clearly the additional years of practice were necessary to reach the top.  And, all of that gray has produced a lot of green.

Please visit my other sports science stories at LiveScience.com

Catching Fly Balls Is A Lot Like Rocket Science

Every Little League outfielder knows the feeling.

With the crack of the bat, you see the ball jump into the air. You take a few quick steps forward. Then, as you watch the ball continue to rise faster, you feel your stomach sink knowing that this one is going over your head. What went wrong?

How our eyes, brains, arms and legs combine to track and catch a fly ball has stumped scientists for more than 40 years.

A new study supports the original theory of it all while offering some practical tips.

By watching fielders shag pop flies, researchers have noticed a few interesting quirks. First, great ballplayers will not sprint to the exact spot on the field where they think the ball will land and then wait for it. Rather, they usually adjust their speed to arrive at the landing spot just as the ball arrives.

In fact, a previous study asked fielders to stand still in the outfield and predict where a fly ball will land. While they did poorly on that test, they then demonstrated that, when allowed to move, they were able to go catch similar fly balls. So, the tracking and prediction mechanism seemed to require movement of the player.

Years ago, physicist Seville Chapman proposed a model to explain how players manage the path of a fly ball so that they arrive to intercept it at just the right time. His theory, called Optical Acceleration Cancellation (OAC), used the acceleration of the ball through the vision field as a guide for player movement.

As a fielder watches the ball rise, he moves either forward or backwards so that the ball moves at a constant speed through his field of vision. If he moves too far forward, the ball will rise faster and may eventually fly over his head. If he takes too many steps back, the ball will appear to rise slower and will drop in front of him.

By managing the ball's position with his movement, a fielder will end up at the right spot at the right time. This explains why the stationary fielders could not predict where the ball would land, as they did not have the benefit of OAC.

If we ask real fielders how they knew where to run to catch a ball, they may not respond with, "Well, I simply adjusted my relative field position to keep the tangent of the vertical optical angle to the ball increasing at a constant rate." So, to test the OAC geometric equations against real life, researchers led by Dinant Kistemaker of the University of Western Ontario, compared the predicted running paths from their mathematical simulation with the real running paths of fielders observed in a previous study.

"We have found that running paths are largely consistent with those observed experimentally," Kistemaker told LiveScience. "Largely, and not completely, because the start of fielders is somewhat strange: They tend to step forward first, irrespective of the fact that they have run either forward or backwards to catch that fly ball."

The research is detailed this month in the journal Human Movement Science.

Will those first few steps forward doom the Little Leaguer to years of fly ball nightmares? Actually, it might be our brain's method of improving its viewpoint.

"For a fielder, making a step is a way of changing the magnitude of the optical acceleration, while preserving its informative value," Kistemaker clarified. "A faster rise of the optical acceleration above the detection threshold may outweigh a possible initial step in the wrong direction. Making an initial step forwards is not only easier than making an initial step backwards, but might also be a better choice."

So, if you're now coaching Little Leaguers, be patient. Their brains may still be learning the math.

Please visit my other sports science articles at LiveScience.com

Runners Pace Themselves Into The Zone

Most regular runners can tell you when they reach that perfect equilibrium of speed and comfort. The legs are loose, the heart is pumping and it feels like you could run at this pace forever.

Researchers at the University of Wisconsin-Madison now have an explanation for this state of running nirvana, and we can thank our ancestors and some evolutionary biology for it.

For years, it has been thought that humans have a constant metabolic energy rate. It was assumed that you would require the same total energy to run one mile, no matter if you ran it in 5 minutes or 10 minutes. Even though your energy burn rate would be higher at faster speeds, you would get there in half the time.

Turns out, however, that each person has an optimal running pace that uses the least amount of oxygen to cover a given distance. The findings, by Karen Steudel, a zoology professor at Wisconsin, and Cara Wall-Scheffler of Seattle Pacific University, are detailed in latest online edition of the Journal of Human Evolution.

Steudel's team tested both male and female runners at six different speeds on a treadmill while measuring their oxygen intake and carbon dioxide output. As expected, each runner had different levels of fitness and oxygen use but there were ideal speeds for each runner that required the least amount of energy

Overall, the optimal speeds for the group were about 8.3 mph (about a 7:13 minutes per mile) for males and 6.5 mph (9:08 min/mile) for females.

The most interesting finding: At slower speeds, about 4.5 mph (13 min/mile), the metabolic efficiency was at its lowest. Steudel explains that at this speed, halfway between a walk and a jog, the runner's gait can be awkward and unnatural.

"What that means is that there is an optimal speed that will get you there the cheapest," Steudel says.

So, why is a zoology professor studying running efficiency? Steudel's previous work has tried to build a theory of why our early ancestors evolved from moving on four limbs to two limbs, also known as bipedalism. She has found that human walking is a more efficient method of getting from point A to point B than on all fours. It might also have been an advantage for hunting.
This latest research could offer some more clues of how we moved on to running. Steudel explains, "This is a piece in the question of whether walking or running was more important in the evolution of the body form of the genus Homo."

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