Are You Allergic To Spring Marathons?

As almost 40,000 runners get set to take part in next month's London Marathon, a new study has found that one in three will suffer from allergies after the event.  Post-marathon sniffles are a common complaint among runners, but they are often put down to infections taking advantage of a depleted immune system caused by the effort involved.

Now, however, researchers at Northumbria University have shown how far symptoms such as itchy eyes, a runny nose and congestion can be attributed to allergic reactions.

A team led by Dr Paula Robson-Ansley recruited 150 runners doing last year's London Marathon and asked them to complete a health questionnaire, take a blood test, and report on the symptoms they experienced up to three days after the event.

Eye and nose problems were reported by 61% of the runners sampled and subsequent blood tests to determine whether immunoglobulin E antibodies were present -- the telltale sign of an allergic reaction -- revealed that 35% of the runners were experiencing an allergy.

The study also found that 14% were specifically allergic to tree pollen. Tree pollen is particularly high in London in April as this is when pollen from high birch and London plane trees is released and tree-pollen counts had been high on the day of the 2010 marathon itself.

Dr Robson-Ansley comments: "These post-event sniffles might seem minor, but there are clear risks that people could go on to develop exercise-induced asthma and airway inflammation. Our survey also revealed that only 8% were taking anti-allergy medication so there is a clear gap between the number of people who could benefit from treatment and the number actually doing so."

In a further result that has implications for next year's Olympic Games, Dr Robson-Ansley found that 29% of the runners were showing an immunoglobulin E reaction to grass pollen.

"The Olympics are taking place during the peak grass-pollen period," she says, "so, if almost three out of ten people are potentially allergic to this common aeroallergen, it is a priority to have Olympic athletes tested before the games so an appropriate treatment regime can be put in place."

Dr Robson-Ansley's advice on athletes and asthma is as follows:

• If you think you have allergies, you need to find out as much as you can and develop a management plan.
• Ask yourself the following:
  • What time of year are you affected?
  • What causes your allergies (blood and skin-prick tests may be necessary)?
  • What are your normal symptoms?
• Consider using a corticosteroid nasal spray or a non-sedating antihistamine as a preventative measure. But be aware that it can take up to two weeks for the treatment to work fully (and avoid taking non-sedating antihistamines around competitions).
• Know your training and competition environment. Find out about typical pollen counts for the location and time of year. Tree pollen for example is usually released in the spring, grass pollen in late spring and early summer, and weed pollens in late summer into autumn.
• Try to minimise exposure to pollens by running when the pollen count is low (cooler and cloudy days are associated with lower pollen counts compared to warmer, drier days). Shower and wash your hair after outside exercise to get rid of residual pollen. Change your clothing and rinse your nose with salt-water washes after exercise.
• Remember that asthmatic athletes take medication regularly and according to instruction. Talk to your GP about whether you might need additional medication or to change your medication if you are training or competing in high pollen or in polluted environments.

Source: Northumbria University

See also: Cherry Juice At The Marathon Finish Line and Bad Air Affects Women More Than Men In Marathons

Research Says Don't Bother With Stretching Before You Run

Stretching before a run neither prevents nor causes injury, according to a study presented at the 2011 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS).  More than 70 million people worldwide run recreationally or competitively, and recently there has been controversy regarding whether runners should stretch before running, or not at all.

This study included 2,729 runners who run 10 or more miles per week. Of these runners, 1,366 were randomized to a stretch group, and 1,363 were randomized to a non-stretch group before running. Runners in the stretch group stretched their quadriceps, hamstrings, and gastrocnemius/soleus muscle groups. The entire routine took 3 to 5 minutes and was performed immediately before running.

The study found that stretching before running neither prevents nor causes injury. In fact, the most significant risk factors for injury included the following:

• history of chronic injury or injury in the past four months;
• higher body mass index (BMI); and
• switching pre-run stretching routines (runners who normally stretch stopping and those who did stretch starting to stretch before running).

"As a runner myself, I thought stretching before a run would help to prevent injury," said Daniel Pereles, MD, study author and orthopaedic surgeon from Montgomery Orthopedics outside Washington, DC. "However, we found that the risk for injury was the same for men and women, whether or not they were high or low mileage runners, and across all age groups. But, the more mileage run or the heavier and older the runner was, the more likely he or she was likely to get injured, and previous injury within four months predisposed to even further injury," he added.

Runners who typically stretch as part of their pre-run routine and were randomized not to stretch during the study period were far more likely to have an injury. "Although all runners switching routines were more likely to experience an injury than those who did not switch, the group that stopped stretching had more reported injuries, implying that an immediate shift in a regimen may be more important than the regimen itself," he added.

The most common injuries sustained were groin pulls, foot/ankle injuries, and knee injuries. There was no significant difference in injury rates between the runners who stretched and the runners who didn't for any specific injury location or diagnosis.

Source: American Academy of Orthopaedic Surgeons

See also: Get Off The Treadmill And On The Trail and High Intensity Workout Gets The Job Done

Youth Baseball Pitchers Need To Stay Under 100 Innings Per Year

For years, sports medicine professionals have talked about youth pitching injuries and the stress the motion causes on developing bones and muscles. In a new, 10-year study published in the February issue of the American Journal of Sports Medicine, researchers showed that participants who pitched more than 100 innings in a year were 3.5 times more likely to be injured.

"The study proved a direct link between innings pitched in youth and adolescent baseball and serious pitching injuries. It highlights the need for parents and coaches to monitor the amount of pitching for the long-term success and health of these young athletes. We need to all work together to end the epidemic of youth sports injuries, and education through campaigns like STOP Sports Injuries is in excellent first step," said lead researcher, Glenn S. Fleisig, PhD, of the American Sports Medicine Institute in Birmingham, Alabama.

The study followed 481 pitchers for 10-years (1999-2008). All were healthy, active youth (aged 9 to 14 years) baseball pitchers at the beginning of the study. Every year each participant was asked whether he played baseball in the previous 12 months and if so what positions, how many innings pitched, what types of pitches he threw, for what teams (spring, summer, fall, winter), and if he participated in baseball showcases. Each player was also asked every year if he had an elbow or shoulder injury that led to surgery or retirement from baseball.

During the 10-year span, five percent of the pitchers suffered a serious injury resulting in surgery or retirement. Two of the boys in the study had surgery before their 13th birthday. Only 2.2 percent were still pitching by the 10th year of the study.

"It is a tough balancing act for adults to give their young athletes as much opportunity as possible to develop skills and strength without exposing them to increased risk of overuse injury. Based on this study, we recommend that pitchers in high school and younger pitch no more than 100 innings in competition in any calendar year. Some pitchers need to be limited even more, as no pitcher should continue to pitch when fatigued," said Fleisig.

The study also looked at the trend of playing pitcher and catcher in the same game, which did appear to double or triple a player's risk of injury but the trend was not statistically significant. The study also could not determine if starting curveballs before age 13 increases the risk of injury.


Source:  American Orthopaedic Society for Sports Medicine and K. E. Wilk, L. C. Macrina, G. S. Fleisig, R. Porterfield, C. D. Simpson, P. Harker, N. Paparesta, J. R. Andrews. Correlation of Glenohumeral Internal Rotation Deficit and Total Rotational Motion to Shoulder Injuries in Professional Baseball Pitchers. The American Journal of Sports Medicine, 2010; DOI: 10.1177/0363546510384223

See also: Do Young Athletes Need Practice Or Genetics? A Conversation With Peter Vint and  Breaking Curveballs And Rising Fastballs Are Optical Illusions

ESPN Study Finds Retired NFL Players Are Heavy Users Of Pain Meds

Retired NFL players use painkillers at a much higher rate than the rest of us, according to new research conducted by investigators at Washington University School of Medicine in St. Louis.  The researchers say the brutal collisions and bone-jarring injuries associated with football often cause long-term pain, which contributes to continued use and abuse of painkilling medications.

The study is published online in the journal Drug and Alcohol Dependence. It involved 644 former NFL players who retired from football between 1979 and 2006. Researchers asked them about their overall health, level of pain, history of injuries, concussions and use of prescription pain pills.

The study found that 7 percent of the former players were currently using painkilling opioid drugs. That's more than four times the rate of opioid use in the general population. Opioids are commonly prescribed for their analgesic, or pain-relieving, properties. Medications that fall within this class of drugs include morphine, Vicodin, codeine and oxycodone.

"We asked about medications they used during their playing careers and whether they used the drugs as prescribed or whether they had ever taken them in a different way or for different reasons," says principal investigator Linda B. Cottler, PhD, professor of epidemiology in psychiatry at Washington University. "More than half used opioids during their NFL careers, and 71 percent had misused the drugs. That is, they had used the medication for a different reason or in a different way than it was prescribed, or taken painkillers that were prescribed for someone else."

Those who misused the drugs during their playing days were more likely to continue misusing them after retiring from football. Some 15 percent of those who misused the drugs as active players still were misusing them in retirement. Only 5 percent of former players who took the drugs as prescribed misused them after they retired from the NFL.

Cottler, director of the Epidemiology and Prevention Research Group in the Department of Psychiatry, says it's not clear from the study whether retired players became dependent on the drugs. What is clear from the survey, she says, is that retired NFL players continue to live with a lot of pain.
"The rate of current, severe pain is staggering," she says. "Among the men who currently use prescription opioids -- whether misused or not -- 75 percent said they had severe pain, and about 70 percent reported moderate-to-severe physical impairment."

Pain was one of the main predictors of current misuse. Another was undiagnosed concussion. Retired NFL players in the study experienced an average of nine concussions each. Some 49 percent had been diagnosed with a concussion at some point during their playing careers, but 81 percent suspected they had concussions that were not diagnosed. Some players believed they may have had up to 200 concussions during their playing days.

"Many of these players explained that they didn't want to see a physician about their concussions at the time," says Simone M. Cummings, PhD, a senior scientist in psychiatry who conducted phone interviews with the former players. "These men said they knew if they reported a concussion, they might not be allowed to play. And if you get taken out of a game too many times, you can lose your spot and get cut from the team."

She says players with suspected-but-undiagnosed concussions reported they borrowed pills from teammates, friends or relatives to treat the pain themselves, thus misusing opioids in an attempt to remain in the NFL. Although 37 percent of the retired players reported that they had received opioids only from a doctor, the other 63 percent who took the drugs during their NFL careers admitted that on occasion they got the medication from someone other than a physician.

Retired players currently misusing opioid drugs also are more likely to be heavy drinkers, according to Cottler.  "So these men are at elevated risk for potential overdose," she says. "They reported more than 14 drinks a week, and many were consuming at least 20 drinks per week, or the equivalent of about a fifth of liquor."

The ESPN sports television network commissioned the study, which also was funded by the National Institute on Drug Abuse. The ESPN program "Outside the Lines" spoke informally to many retired players about their use of painkillers. One reported taking up to 1,000 Vicodin tablets per month. Another reported ingesting 100 pills per day and spending more than $1,000 per week on painkillers.
Former St. Louis Rams offensive lineman Kyle Turley said in a statement to ESPN that he knew of many players who took drugs to help them deal with the pain inflicted by the injuries they sustained in the NFL.

"I know guys that have bought thousands of pills," Turley said. "Tons of guys would take Vicodin before a game."

The researchers say offensive linemen had particularly high rates of use and misuse of opioids.
"The offensive linemen were twice as likely as other players to use or misuse prescription pain medicines during their NFL careers," Cottler says. "In addition, this group tends to be overweight and have cardiovascular problems, so they represent a group of former players whose health probably should be monitored closely."

In fact, Cottler says it would be a good idea to continue monitoring everyone who has played in the NFL. She says this study revealed that some 47 percent of retired players reported having three or more serious injuries during their NFL careers, and 61 percent said they had knee injuries. Over half, 55 percent, reported that an injury ended their careers.

"These are elite athletes who were in great physical condition when their playing careers began," she says. "At the start of their careers, 88 percent of these men said they were in excellent health. By the time they retired, that number had fallen to 18 percent, primarily due to injuries. And after retirement, their health continued to decline. Only 13 percent reported that they currently are in excellent health. They are dealing with a lot of injuries and subsequent pain from their playing days. That's why they continue to use and misuse pain medicines."

Source:   Washington University School of Medicine and Linda B. Cottler, Arbi Ben Abdallah, Simone M. Cummings, John Barr, Rayna Banks, Ronnie Forchheimer. Injury, pain and prescription opioid use among former NFL football players. Drug and Alcohol Dependence, 2011; DOI: 10.1016/j.drugalcdep.2010.12.003

See also:  NFL Concussions Taking Bigger Toll On Players and NFL Linemen Trade Health For Super Bowl Rings

Exercise - The Cure For The Common Cold

People who are physically fit and active have fewer and milder colds, indicates research published online in the British Journal of Sports Medicine.  The US researchers base their findings on 1,000 adults up to the age of 85 whose respiratory health was tracked for 12 weeks during the autumn and winter of 2008. 

Six out of 10 participants were women, and four out of 10 were aged between 18 and 39; 40% were middle aged, and one in four were aged 60 and older.

All the participants reported back on how frequently they took aerobic exercise and rated their fitness levels using a validated 10 point scoring system. They were also asked about lifestyle, diet and recent stressful events, as these can all affect immune system response.  The number of days with cold symptoms varied considerably between winter and autumn, with an average of 13 days in the winter and 8 days in the autumn.

Being older, male, and married, seemed to reduce the frequency of colds, but after taking account of other influential factors, the most significant factors were perceived fitness and the amount of exercise taken.

The number of days with symptoms among those who said they were physically active on five or more days of the week and felt fit was almost half (43% to 46% less) that of those who exercised on only one or fewer days of the week.  The severity of symptoms fell by 41% among those who felt the fittest and by 31% among those who were the most active.

In the US, an average adult can expect to have a cold two to four times a year, while children can catch between half a dozen and 10 colds a year, on average, all of which costs the US economy around $40 billion dollars.

Bouts of exercise spark a temporary rise in immune system cells circulating around the body, say the authors. Although these levels fall back within a few hours, each bout is likely to enhance surveillance of harmful viruses and bacteria, so reducing the number and severity of infections, such as the common cold.

Source: BMJ-British Medical Journal and Upper respiratory tract infection is reduced in physically fit and active adults. British Journal of Sports Medicine, 2010; DOI: 10.1136/bjsm.2010.077875

See also: Training In The Heat Even Helps Competing In Cool Temps and Is Exercise The Cure For Depression?

New Return-To-Play Guidelines For Sports Concussions

The American Academy of Neurology (AAN) is calling for any athlete who is suspected of having a concussion to be removed from play until the athlete is evaluated by a physician with training in the evaluation and management of sports concussion.

The request is one of five recommendations from a new position statement approved by the AAN's Board of Directors that targets policymakers with authority over determining the policy procedures for when an athlete suffers from concussion while participating in a sporting activity.

According to the Centers for Disease Control, sports-related concussions occur in the United States three million times per year, and among people ages 15 to 24 are now second only to motor vehicle accidents as a leading cause of traumatic brain injury.


"While the majority of concussions are self-limited injuries, catastrophic results can occur and we do not yet know the long-term effects of multiple concussions," said Jeffrey Kutcher, MD, MPH, chair of the AAN's Sports Neurology Section, which drafted the position statement. "We owe it to athletes to advocate for policy measures that promote high quality, safe care for those participating in contact sports."

According to the new statement, no athlete should be allowed to participate in sports if he or she is still experiencing symptoms from a concussion, and a neurologist or physician with proper training should be consulted prior to clearing the athlete for return to participation.

In addition, the AAN recommends a certified athletic trainer be present at all sporting events, including practices, where athletes are at risk for concussion. Education efforts should also be maximized to improving the understanding of sports concussion by all athletes, parents and coaches. "We need to make sure coaches, trainers, and even parents, are properly educated on this issue, and that the right steps have been taken before an athlete returns to the field," said Kutcher, who is also director of the University of Michigan's Neurosport program.

In 1997, the AAN published a guideline on the management of sports concussion that defines concussion grade levels and provides recommendations. The guideline is currently being updated.

Source: American Academy of Neurology

See also: NFL Concussions Taking Bigger Toll On Players and Youth Sports Concussions Double In Last Ten Years

NFL Concussions Taking Bigger Toll On Players

NFL players with concussions now stay away from the game significantly longer than they did in the late 1990s and early 2000s, according to research in Sports Health (owned by American Orthopaedic Society for Sports Medicine and published by SAGE). The mean days lost with concussion increased from 1.92 days during 1996-2001 to 4.73 days during 2002-2007.

In an effort to discover whether concussion injury occurrence and treatment had changed, researchers compared those two consecutive six-year periods to determine the circumstances of the injury, the patterns of symptoms, and a player's time lost from NFL participation. Those time periods were chosen because concussion statistics were recorded by NFL teams using the same standardized form. It recorded player position, type of play, concussion signs and symptoms, loss of consciousness and medical action taken.

Researchers found that in 2002-2007 there were fewer documented concussions per NFL game overall, especially among quarterbacks and wide receivers. But there was a significant increase in concussions among tight ends. Symptoms most frequently reported included headaches, dizziness, and problems with information processing and recall.

Significantly fewer concussed players returned to the same game in 2002-2007 than in 1996-2001 and 8% fewer players returned to play in less than a week. That number jumped to 25% for those players who lost consciousness as a result of the injury.

"There are a number of possible explanations for the decrease in percentages of players returning to play immediately and returning to play on the day of the injury as well as the increased days out after (a concussion) during the recent six year period compared to the first six year period," write authors Ira R. Casson, M.D.; David C. Viano, Dr. med.; Ph.D., John W. Powell, Ph.D.; and Elliot J. Pellman, M.D. "These include the possibility of increased concussion severity, increased player willingness to report symptoms to medical staff, adoption of a more cautious conservative approach to concussion management by team medical personnel and a possible effect of changes in neuropsychological (NP) testing."

Source:  SAGE Publications and I. R. Casson, D. C. Viano, J. W. Powell, E. J. Pellman. Twelve Years of National Football League Concussion Data. Sports Health: A Multidisciplinary Approach, 2010; DOI: 10.1177/1941738110383963

See also: Football Players May Still Injure Brain Even Without A Concussion and Youth Sports Concussions Double In Last Ten Years

Football Players May Still Injure Brain Even Without A Concussion

Thomas Talavage, co-director of the Purdue MRI Facility, prepares to test a Jefferson High School football player. (Credit: Purdue University photo/Andrew Hancock)

A study by researchers at Purdue University suggests that some high school football players suffer undiagnosed changes in brain function and continue playing even though they are impaired.
"Our key finding is a previously undiscovered category of cognitive impairment," said Thomas Talavage, an expert in functional neuroimaging who is an associate professor of biomedical engineering and electrical and computer engineering and co-director of the Purdue MRI Facility.

The findings represent a dilemma because they suggest athletes may suffer a form of injury that is difficult to diagnose.

"The problem is that the usual clinical signs of a head injury are not present," said Larry Leverenz, an expert in athletic training and a clinical professor of health and kinesiology. "There is no sign or symptom that would indicate a need to pull these players out of a practice or game, so they just keep getting hit."

Findings are detailed in a research paper appearing online this week in the Journal of Neurotrauma.
The team of researchers screened and monitored 21 players at Jefferson High School in Lafayette, Ind.
"The athletes wore helmets equipped with six sensors called accelerometers, which relay data wirelessly to equipment on the sidelines during each play," said Eric Nauman, an associate professor of mechanical engineering and an expert in central nervous system and musculoskeletal trauma.

Impact data from each player were compared with brain-imaging scans and cognitive tests performed before, during and after the season. The researchers also shot video of each play to record and study how the athletes sustained impacts.

Whereas previous research studying football-related head trauma has focused on players diagnosed with concussions, the Purdue researchers tested all of the players. They were surprised to find cognitive impairment in players who hadn't been diagnosed with concussions.

The research team identified 11 players who either were diagnosed by a physician as having a concussion, received an unusually high number of impacts to the head or received an unusually hard impact. Of those 11 players, three were diagnosed with concussions during the course of the season, four showed no changes and four showed changes in brain function.

"So half of the players who appeared to be uninjured still showed changes in brain function," Leverenz said. "These four players showed significant brain deficits. Technically, we aren't calling the impairment concussions because that term implies very specific clinical symptoms, such as losing consciousness or having trouble walking and speaking. At the same time, our data clearly indicate significant impairment."

The findings support anecdotal evidence that football players not diagnosed with concussions often seem to suffer cognitive impairment.

Researchers evaluated players using a GE Healthcare Signa HDx 3.0T MRI to conduct a type of brain imaging called functional magnetic resonance imaging, or fMRI, along with a computer-based neurocognitive screening test.

"We're proud of our association with Purdue and feel longitudinal studies will provide a valuable platform to better study brain injuries," said Jonathan A. Murray, general manager of cross business programs for GE Healthcare.

The research could aid efforts to develop more sensitive and accurate methods for detecting cognitive impairment and concussions; more accurately characterize and model cognitive deficits that result from head impacts; determine the cellular basis for cognitive deficits after a single impact or repeated impacts; and develop new interventions to reduce the risk and effects of head impacts.

"By integrating the fMRI with head-based accelerometers and computer-based cognitive assessment, we are able to detect subtle levels of neurofunctional and neurophysiological change," Nauman said. "These data provide an opportunity to accurately track both the initial changes as well as the recovery in cognitive performance."

(Credit: iStockphoto/Bill Grove

The ongoing research may help to determine how many blows it takes to cause impairment, which could lead to safety guidelines on limiting the number of hits a player receives per week.  "We're not yet sure exactly how many hits this is, but it's probably around 50 or 60 per week, which is not uncommon," Nauman said. "We've had kids who took 1,600 impacts during a season."

The research paper was written by Nauman, Leverenz, Talavage, Katie Morigaki, a graduate student in the Department of Health and Kinesiology, biomedical engineering graduate student Evan Breedlove, mechanical engineering graduate student Anne Dye, electrical and computer engineering graduate student Umit Yoruk, and Henry Feuer, a physician and neurosurgeon in the Department of Neurosurgery at the Indiana University School of Medicine.

Feuer is a neurosurgical consultant to the National Football League's Indianapolis Colts and a member of NFL subcommittees assessing the effects of mild traumatic brain injury.

The researchers studied the football players last season and are continuing the work this season.
The helmet-sensor data demonstrated that undiagnosed players who didn't show impairment received blows in many areas of the head, but the undiagnosed players who showed impairment received a large number of blows primarily to the top and front. This part of the brain is involved in "working memory," including visual working memory, a form of short-term memory for recalling shapes and visual arrangement of objects such as the placement of furniture in a room, Nauman said.
"These are kids who put their head down and take blow after blow to the top of the head," said Nauman, who also is an associate professor of biomedical engineering and basic medical sciences and leads Purdue's Human Injury Research and Regenerative Technologies Laboratory. "We've seen this primarily in linebackers and linemen, who tend to take most of the hits."

Helmet sensor data indicate impact forces to the head range from 20 to more than 100 Gs.
"To give you some perspective, a roller coaster subjects you to about 5 Gs and soccer players may experience up to 20 G accelerations from heading the ball," Nauman said.
Head impacts cause the brain to bounce back and forth inside the skull, damaging neurons or surrounding tissue. The trauma can either break nerve fibers called axons or impair signaling junctions between neurons called synapses.

The findings suggest the undiagnosed players suffer a different kind of brain injury than players who are diagnosed with a concussion.

"To be taken out of a game you have to show symptoms of neurological deficits -- unsteady balance, blurred vision, ringing in the ears, headaches and slurred speech," Leverenz said. "Unlike the diagnosed concussions, however, these injuries don't affect how you talk, whether you can walk a straight line or whether you know what day it is."

The fMRI reveals information about brain metabolism and blood flow, showing which parts of the brain are most active during specific tasks, Talavage said.

"One of the most challenging aspects of treating concussions is diagnosing the part of the brain that has been damaged," he said.

The fMRI data from before, during and after the season were compared to see whether there was any difference in brain activity that indicated impairment. The players also were studied using a standard cognitive test to show how well they were able to remember specific letters, words and patterns of lines.

The work may enable researchers to learn whether high school players accumulate damage over several seasons or whether they recover fully from season to season. The researchers have found that players diagnosed with concussions or who showed marked cognitive impairment had not yet recovered by the end of the season.

New preliminary data, however, suggests the players might recover before the start of the next season, but additional research is needed to determine the extent of recovery, Talavage said.
The work brings together faculty members from Purdue's College of Engineering and the new College of Health and Human Sciences along with research partners at GE Healthcare. The multidisciplinary team includes researchers specializing in neuroimaging, brain health, biomechanics, clinical sports medicine and analytical modeling.

The research group, called the Purdue Acute Neural Injury Consortium, also is studying ways to reduce traumatic brain injury in soldiers who suffer concussions caused by shock waves from explosions.  "There are numerous parallels between head injuries experienced by soldiers and football players," Nauman said.

Other researchers in the consortium are Dennis A. Miller, a sports medicine expert; Charles A. Bouman, the Michael J. and Katherine R. Birck Professor of Electrical and Computer engineering and co-director of the Purdue MRI Facility; and Alexander L. Francis, an expert in learning and cognitive processing and an associate professor of speech, language and hearing sciences.

The work has been funded by the Indiana Department of Health and GE Healthcare. The researchers would like to extend their study to more high schools and are seeking additional funding for the work.
Researchers are working to create a helmet that reduces the cumulative effect of impacts, said John C. Hertig, executive director of the Alfred Mann Institute for Biomedical Development at Purdue.

"We're funding the development of a novel injury mitigation system created by researchers at Purdue for use in sports or military helmets," Hertig said. "This technology is targeted at mitigating the collective impacts absorbed by the brain in such a way as to dissipate the harmful energy that occurs during repeated impacts. Football linemen, soccer and hockey players, and others will benefit from the re-engineering of a sports helmet design created by Eric Nauman and his team."

Source:  Purdue University and Thomas M. Talavage, Eric Nauman, Evan L. Breedlove, Umit Yoruk, Anne E Dye, Katie Morigaki, Henry Feuer, Larry J. Leverenz. Functionally-Detected Cognitive Impairment in High School Football Players Without Clinically-Diagnosed Concussion. Journal of Neurotrauma, 2010; : 101001044014052 DOI: 10.1089/neu.2010.1512

See also: Hockey Hits Are Hurting More and Lifting The Fog Of Sports Concussions

Youth Sports Concussions Double In Last Ten Years

A new study from Hasbro Children's Hospital finds visits to emergency departments for concussions that occurred during organized team sports have increased dramatically over a 10-year period, and appear to be highest in ice hockey and football. The number of sports-related concussions is highest in high school-aged athletes, but the number in younger athletes is significant and rising. The study is published in the September 2010 issue of Pediatrics and is now available online ahead of print.

In a review of national databases of emergency department (ED) visits, there were 502,000 visits to EDs for concussions in children aged 8 to 19 years in the period from 2001 through 2005; of those 65 percent were in the 14- to 19-year old age group while 35 percent were in the 8- to 13-year-old age group. Approximately half of all the ED visits for concussions were sports-related, and an estimated 95,000 of those visits were for concussions that occurred from one of the top five organized team sports: football, basketball, baseball, soccer and ice hockey.

The researchers also note that in the period from 2001 through 2005, approximately four in 1,000 children aged 8 to 13 and six in 1,000 aged 14 to 19 had an ED visit for a sport-related concussion.
Lisa Bakhos, MD, is a recently graduated fellow who was practicing at Hasbro Children's Hospital at the time she led the study. Bakhos says, "Our data show that older children have an overall greater estimated number of ED visits for sport-related concussion compared to younger children. Younger children, however, represent a considerable portion of sport-related concussions, approximately 40 percent."

The researchers found that ED visits for organized team sport-related concussions doubled over the time period depicted and increased by over 200 percent in the 14- to 19-year old age group, while overall participation decreased by 13 percent in the same time period. Bakhos comments, "What was striking in our study is that the number of sport-related concussions has increased significantly over a 10-year period despite an overall decline in participation. Experts have hypothesized that this may be due to an increasing number of available sports activities, increasing competitiveness in youth sports, and increasing intensity of practice and play times. However, the increasing numbers may also be secondary to increased awareness and reporting."

James Linakis, MD, PhD, is a pediatric emergency medicine physician with Hasbro Children's Hospital and its Injury Prevention Center and is the senior author on the paper. He comments, "Our assessment highlights the need for further research and injury prevention strategies into sport-related concussion. This is especially true for the young athlete, with prevailing expert opinion suggesting that concussion in this age group can produce more severe neurologic after-effects, such as prolonged cognitive disturbances, disturbed skill acquisition, and other long-term effects."

Despite the apparent increase in concussions in youth athletes, there are no comprehensive return-to-play guidelines for young athletes. The researchers also note that there are no evidence-based management guidelines for the treatment of these injuries, while there is agreement that young children cannot be managed in the same way as older adolescents.

Linakis, who is also a physician with University Emergency Medicine Foundation and an associate professor at The Warren Alpert Medical School of Brown University, says, "Children need not only physical, but cognitive rest, and a slow-graded return to play and school after such injuries. As a result of this study, it is clear that we need more conservative guidelines for the management of younger children who suffer concussions." Return-to-play assessments might include such strategies as neuropsychological testing, functional MRI, visual tracking technology and balance dysfunction tracking.

Bakhos concludes, "What this research tells us is that we need additional studies to provide guidance in management, prevention strategies and education for practitioners, coaches and athletes."


Source: Lifespan and Bakhos, Linakis, Lockhart, Myers, Linakis. Emergency Department Visits for Concussion in Young Child Athletes. Pediatrics, 8/30/2010 DOI: 10.1542/peds.2009-3101

See also: Body Checking Not The Main Cause Of Youth Hockey Injuries and Science Fair Project Leads To New Sports Concussion Test

Kicking Style Of Women Soccer Players May Cause Injury

Significant differences in knee alignment and muscle activation exist between men and women while kicking a soccer ball, according to a study published this month in the Journal of Bone and Joint.

Data reveal that males activate certain hip and leg muscles more than females during the motion of the instep and side-foot kicks -- the most common soccer kicks -- which may help explain why female players are more than twice as likely as males to sustain an Anterior Cruciate Ligament (ACL) injury.

Soccer is one of the fastest-growing sports in the United States with approximately 20 million registered players and an annual participation increase of more than 20 percent , according to statistics from the National Collegiate Athletic Association (NCAA) . Women also are playing this sport on more competitive levels. Prior research shows that females are more prone to non-contact ACL injuries than males and though many theories exist, a direct cause for the disparity is unknown.

"By analyzing the detailed motion of a soccer kick in progress, our goal was to home in on some of the differences between the sexes and how they may relate to injury risk," said orthopaedic surgeon Robert H. Brophy, MD, study author and assistant professor of orthopedics, Washington University School of Medicine in St. Louis. "This study offers more information to help us better understand the differences between male and female athletes, particularly soccer players."

Dr. Brophy and his colleagues from the Motion Analysis Laboratory and Sports Medicine Service at the Hospital for Special Surgery in New York used 3-D video-based motion analysis and electromyography to examine the differences between 13 male and 12 female college soccer players during the action of kicking a soccer ball.

Using eight to 10 video cameras, 21 retroreflective markers and 16 electrodes simultaneously, researchers measured the activation of seven muscles (iliacus, gluteus maximus, gluteus medius, vastus lateralis, vastus medialis, hamstrings and gastrocnemius) in both the kicking and supporting legs; as well as two additional muscles (hip adductors and tibialis anterior) in the kicking leg only. Five instep and five side-foot kicks were recorded for each player. Muscle activation was recorded as a percentage of maximum voluntary isometric contraction.

They found that male players activate the hip flexors (inside of the hip) in their kicking leg and the hip abductors (outside of the hip) in their supporting leg more than females.

* In the kicking leg, men generated almost four times as much hip flexor activation as females (123 percent in males compared to 34 percent in females).
* In the supporting leg, males generated more than twice as much gluteus medius activation (124 percent in males compared with 55 percent in females) and vastus medialis activation (139 percent in males compared with 69 percent in females).

"Activation of the hip abductors may help protect players against ACL injury," said Dr. Brophy, a former collegiate and professional soccer player and past head team physician for the former St. Louis Athletica professional women's soccer club. "Since females have less activation of the hip abductors, their hips tend to collapse into adduction during the kick, which can increase the load on the knee joint in the supporting leg, and potentially put it at greater risk for injury."

Brophy said that although the study does not establish a direct cause-and-effect relationship between muscle activation and knee alignment and ACL injuries, the finding "moves us toward better understanding of what may contribute to differences in injury risk between the sexes and what steps we might take to offset this increased risk in females."

The current research in the area of ACL injury prevention has shown some promise. For example, in 2008, the Centers for Disease Control and Prevention published a study that found a new training program called the Prevent Injury and Enhance Performance (PEP) program, was effective in reducing ACL injuries in female soccer players. Developed by the Santa Monica Orthopedic and Sports Medicine Research Foundation and supported by the American Academy of Orthopaedic Surgeons (AAOS) among other medical and athletic associations, PEP is an alternative warm-up regimen that focuses on stretching, strengthening and improving balance and movements and can be conducted during regular practice time and without special equipment.

"Programs focusing on strengthening and recruiting muscles around the hip may be an important part of programs designed to reduce a female athletes' risk of ACL injury," said Dr. Brophy. "Coaches and trainers at all levels, from grade school through professional, should consider using strategies that demonstrate potential to prevent these injuries."

He said that additional research is warranted to investigate how the differences in hip muscle activation and alignment between the sexes may relate to differences in the risk of lower extremity injury among athletes in soccer and other sports.

Source:  American Academy of Orthopaedic Surgeons

See also: Goalkeepers Use Clues To Guess Direction Of Penalty Kick and Youth Sports Coaches Should Prioritize Teaching Over Winning

Knee-Friendly Landings Reduce Force By 56 Percent

Anterior cruciate ligament injuries are a common and debilitating problem, especially for female athletes. A new study from UC Davis shows that changes in training can reduce shear forces on knee joints and could help cut the risk of developing ACL tears.

"We focused on an easy intervention, and we were amazed that we could reduce shear load in 100 percent of the volunteers," said David Hawkins, professor of neurobiology, physiology and behavior at UC Davis. Hawkins conducted the study at the UC Davis Human Performance Laboratory with graduate student Casey Myers.

The anterior cruciate ligament lies in the middle of the knee and provides stability to the joint. Most ACL injuries do not involve a collision between players or a noticeably bad landing, said Sandy Simpson, UC Davis women's basketball coach.

"It almost always happens coming down from a rebound, catching a pass or on a jump-stop lay-up," Simpson said. "It doesn't have to be a big jump."

Hawkins and Myers worked with 14 female basketball players from UC Davis and local high schools. They fitted them with instruments and used digital cameras to measure their movements and muscle activity, and calculated the forces acting on their knee joints as they practiced a jump-stop movement, similar to a basketball drill.

First, they recorded the athletes making their normal movement. Then they instructed them in a modified technique: Jumping higher to land more steeply; landing on their toes; and bending their knees more deeply before taking off again.

After learning the new technique, all 14 volunteers were able to reduce the force passed up to the knee joint through the leg bone (the tibial shear force) by an average of 56 percent. At the same time, the athletes in the study actually jumped an inch higher than before, without losing speed.

Hawkins recommends warm-ups that exercise the knee and focusing on landing on the toes and balls of the feet. The study does not definitively prove that these techniques will reduce ACL injuries, Hawkins said: that would require a full clinical trial and follow-up. But the anecdotal evidence suggests that high tibial shear forces are associated with blown knees.

Hawkins and Myers shared their findings with Simpson and other UC Davis women's basketball and soccer coaches, as well as with local youth soccer coaches.  The research was published online Aug. 3 in the Journal of Biomechanics.

Simpson said that the team had tried implementing some changes during last year's preseason, but had found it difficult to continue the focus once the full regular season began. In live play, athletes quickly slip back to learned habits and "muscle memory" takes over, he noted. More intensive off-court training and practice would be needed to change those habits, he said.

"We will be talking about this again this season," Simpson said. Implementing the techniques in youth leagues, while children are still learning how to move, might have the most impact, he said.

Source: University of California - Davis - Health System

See also: Barefoot Is Better and For Rock Climbers, Endurance Is Key To Performance

Too Much Altitude Training Can Hurt Athletic Performance

New research suggests that athletes and footballers may want to limit the time they spend training at altitude to improve their performance. An Oxford University study has found that people with a rare condition that mimics being at high altitude for long periods show metabolic differences that actually reduce their endurance and physical performance.

The study is published in the journal PNAS and was funded by the British Heart Foundation and the Wellcome Trust.

Athletes from many endurance disciplines use altitude training as part of their yearly training programme. England footballers, as with many of the teams in the World Cup, spent time at altitude acclimatising for the competition in South Africa.

The body reacts to the low levels of oxygen at high altitude, first of all by breathing harder and the heart pumping more blood, but then through producing more red blood cells and increasing the density of blood vessels in the body's muscles. All of this serves to get more oxygen and fuel to the muscles.
However, an extended stay at altitude can bring a loss of the muscle's ability to use oxygen to carry out work. The number of mitochondria, the oxygen-using powerhouses of the cell, falls with a prolonged stay at high altitude.

"It is the higher capacity to deliver fuel to muscles that athletes are interested in," explains lead author Dr Federico Formenti of the Department of Physiology, Anatomy and Genetics at the University of Oxford. 'However, it's not clear how long they should train at altitude or how high up they need to be to get the optimal benefits."

A protein called hypoxia-inducible factor (HIF) is central to the body's response to high altitude. It is stimulated by low levels of oxygen and sets many of these processes in train.

The Oxford University researchers set out to study the metabolism of people with a rare genetic change that leads to continually high levels of HIF, even when levels of oxygen are normal. The increased levels of HIF mean that the condition -- called Chuvash polycythemia or CP -- is a good model for changes that occur in people who stay at high altitude for long periods.  CP can also offer insight into the fundamental processes where oxygen supply in the body is limited, such as in lung disease, heart disease, vascular disease and cancer.

Only around 20 people in the UK are known to have this mild condition. It is typically only diagnosed when a standard blood test shows increased numbers of red blood cells and further tests are done.

The team compared the performance of five people with CP with five matched controls. In an exercise bike test, in which study participants were asked to keep a constant pedal rate against a steadily increasing resistance, those with CP had to stop exercising earlier. The maximum work rate they achieved for their weight was 30% less than controls.

Studies of metabolites present in calf muscles under light exercise also indicated that CP patients experienced greater fatigue. Finally, there were differences in expression of metabolic genes in the CP patients' muscles. This could suggest their metabolism makes less efficient use of the fuel available and may explain their reduced exercise capacity.

"We found that the metabolism of CP patients is different and leads to poorer physical performance and endurance," says Dr Formenti. "Although this is a small study -- necessarily so because of there are so few people with the condition -- the results are striking. The differences seen in those with Chuvash polycythemia were large, and five patients were more than enough to see this effect."

"With the help of our volunteers with Chuvash polycythemia, we now understand these fundamental processes better. This understanding should eventually lead to better medical care in the many conditions where oxygen supply in the body is limited, such as heart disease and cancer,"
says principal investigator Professor Peter Robbins of Oxford University.

Source: University of Oxford and Regulation of human metabolism by hypoxia-inducible factor Proceedings of the National Academy of Sciences, 2010

See also: Vancouver Olympians Prepared For High And Low Altitudes and High Intensity Workout Gets The Job Done

Little League Arm Injuries Jump Up

Throwing arm injuries are on the rise in Little League and other youth baseball programs. After these injuries occur, many players are out for the season; others require surgery and must refrain from play for an even longer duration; still others sustain injuries so severe that they cause permanent damage and are unable to continue playing baseball.

Three new studies presented at the at the 2010 Annual Meeting of the American Academy of Orthopaedic Surgeons (AAOS) address this critical issue, each offering new solutions to help prevent these injuries.

Pitchers and catchers under the age of 15 often experience tightness of a shoulder ligament known as the posterior-inferior glenohumeral ligament. If this ligament is not stretched, it will become increasingly tighter and more prone to pain or injury as the player ages, if that player continues to play baseball.

A study of 1,267 youth baseball players, led by Charles Metzger, MD, an orthopaedic surgeon specializing in upper extremities in Houston, Texas, found that a simple stretch known as the posterior capsular stretch can help.



"A posterior capsular stretch is done after play and since it is different from the general stretches players already know, it must be taught," says Dr. Metzger. "Once learned, however, it is very simple, and takes only five minutes to complete. Nearly 97 percent of young players who performed the stretch properly and consistently reported shoulder improvement."

Dr. Metzger supports Safe Throw, an injury-prevention and rapid return-to-play program. Instructions and diagrams showing how to perform the posterior capsular stretch can be found on www.safethrow.com.


The elbow is the most frequently reported area of overuse injury in child and adolescent baseball players. One type of overuse includes osteochondral lesions, which are tears or fractures in the cartilage and underlying bone, covering the elbow joint.

In a study led by Tetsuya Matsuura, MD, Department of Orthopedics, The University of Tokushima Graduate School, Institute of Health Bioscience in Tokushima, Japan, 152 baseball players were observed (ranging in age from 8 to12) for one season to study the injury incidence in relation to their playing positions. These players had no history of problematic elbow pain.

The results were as follows:

* 38 players, or 25 percent complained of elbow pain
* 26 (68.4 percent) had limitations of range of motion and/or tenderness on the elbow, and/or valgus stress pain (a stressful force placed upon the ligaments on the inner side of the elbow joint); and
* 22 (84.6 percent) had osteochondral lesions including:

• 12 pitchers (54.6 percent)
• 6 catchers (27.3 percent)
• 3 infielders (13.6 percent)
• 1 outfielder (4.5 percent).

Dr. Matsuura concluded, "Twenty-five percent of child and adolescent baseball players have elbow pain and nearly 15 percent sustain osteochodral lesions per year and pitchers have the highest rate of osteochondral lesions. If overuse injuries such as osteochrondral lesions occur, prompt diagnosis and treatment can prevent this injury from causing long-term damage. Better awareness and education among parents, players and especially coaches about risk factors can help prevent these injuries."

Reviewing -- and adhering to -- youth baseball throwing guidelines can help prevent injury

In another presentation, led by George A. Paletta, Jr., MD, an orthopaedic surgeon at the Orthopedic Center of St. Louis and Medical Director/Head Team Physician of the St. Louis Cardinals, discussed the increase in elbow injuries of young baseball players, including the increasing number of ligament reconstruction or "Tommy John" procedures performed.

Despite these increases, Dr. Paletta says there are identifiable -- and controllable -- risk factors of which young athletes, parents and coaches should be aware, to help reduce injury.

"A young athlete should never throw through pain or continue to pitch when he or she is obviously fatigued," says Dr. Paletta. "Additionally, parents should familiarize themselves with the recommended single game, weekly and season total pitch counts, suggested recovery times, and recommended ages for learning various pitches."

Dr. Paletta stresses that there must be a greater focus on education and research in this area, or more young baseball players will sustain serious injury.

Source: American Academy of Orthopaedic Surgeons

See also: Kids' Baseball Injuries Down But Some Still Play "Until It Hurts" and Baseball Brains - Pitching Into The World Series

Aerobic Fitness Helps Brains of Multiple Sclerosis Patients

Highly fit multiple sclerosis patients perform significantly better on tests of cognitive function than similar less-fit patients, a new study shows.  In addition, MRI scans of the patients showed that the fitter MS patients showed less damage in parts of the brain that show deterioration as a result of MS, as well as a greater volume of vital gray matter.

"We found that aerobic fitness has a protective effect on parts of the brain that are most affected by multiple sclerosis," said Ruchika Shaurya Prakash, lead author of the study and assistant professor of psychology at Ohio State University.  "As a result, these fitter patients actually show better performance on tasks that measure processing speed."

The study, done with colleagues Robert Motl and Arthur Kramer of the University of Illinois and Erin Snook of the University of Massachusetts, Amherst, appears online in the journal Brain Research and will be published in a future print edition.


The study involved 21 women diagnosed with relapsing-remitting MS. They were compared with 15 age- and education-matched healthy female controls. The study assessed fitness, cognitive function, and structural changes in all participants.  In order to measure fitness levels, the participants underwent a VO2 max test, in which they rode a stationary bicycle until they felt exhausted. During the test, they breathed into a mask which measured their oxygen consumption.

All the women also took a variety of tests designed to evaluate cognitive functions, such as processing speed and selective attention. In one test, for example, participants had to write down in one minute as many words as they could think of that began with the letter "F." MS patients generally perform poorly on these tests compared to healthy people.  The third analysis involved MRIs of the participants, revealing any damage to their brains.

As expected, the MS patients did much worse than the healthy controls on the tests of brain functioning, and showed more deterioration in their brains as revealed through the MRIs.  But what was interesting, Prakash said, was the significant differences between the more aerobically fit MS patients and those who were less fit.

Take, for instance, lesions, which are the characteristic feature of MS. Lesions are areas of inflammation in the central nervous system in which neurons have been stripped of myelin, an insulating protein.

"Physically fit MS patients had fewer lesions compared to those who weren't as fit and the lesions they did have tended to be smaller," Prakash said. "This is significant and can help explain why the higher-fit patients did better on tests of brain functioning."

Aerobic fitness was also associated with less-damaged brain tissue in MS patients, both the gray matter and white matter.  Gray matter is the cell bodies in the brain tissue, while white matter is the fibers that connect the various gray matter areas.

The study found that fitness in MS patients was associated with larger volume of gray matter, accounting for about 20 percent of the volume in gray matter. That's important, Prakash said, because gray matter is linked to brain processing skills.

"Even in gray matter that appeared relatively healthy, we found a deterioration in the volume in MS patients," she said. "But for some of the highest fit MS patients, we found that their gray matter volume was nearly equivalent to that of healthy controls."

Another MRI analysis involved the integrity of the white matter in the brain. In MS patients, the white matter deteriorates as the myelin is stripped from neurons. Again, higher-fit MS patients showed less deterioration of white matter compared to those who were less fit.

Overall, the three MRI tests in this study showed that parts of the brain involved in processing speed are all negatively affected by MS -- but less so in patients who are aerobically fit.

Prakash noted that other researchers have found that exercise promotes the production of nerve growth factors, proteins which are important for the growth and maintenance of neurs in the brain.  "Our hypothesis is that aerobic exercise enhances these nerve growth factors in MS patients, which increases the volume of the gray matter and increases the integrity of the white matter," she said.  "As a result there is an improvement in cognitive function."

Prakash and her colleagues plan to extend this research by studying whether exercise interventions with MS patients can actually improve their cognition and have positive physical effects on the brain.

"For a long time, MS patients were told not to exercise because there was a fear it could exacerbate their symptoms," she said.  "But we're finding that if MS patients exercise in a controlled setting, it can actually help them with their cognitive function."

The research was supported by a grant from the National Institute on Aging.

Source: Ohio State University
See also: Take Your Brain To The Gym,  Boomer Brains Need Exercise and Exercise May Help Schizophrenia Patients

Exercise May Help Schizophrenia Patients

Potentially beneficial brain changes (an increase in the volume of an area known as the hippocampus) occur in response to exercise both in patients with schizophrenia and healthy controls, according to a report in the February issue of Archives of General Psychiatry, one of the JAMA/Archives journals. The findings suggest that the brain retains some plasticity, or ability to adapt, even in those with psychotic disorders.

Schizophrenia is known to be associated with a reduced volume in the area of the brain known as the hippocampus, which helps regulate emotion and memory, according to background information in the article. "In contrast to other illnesses that may display psychotic features, such as bipolar disorder, schizophrenia is often characterized by incomplete recovery of psychotic symptoms and persistent disability," the authors write. "These clinical features of illness may relate to an impairment of neural plasticity or mechanisms of reorganizing brain function in response to a challenge."

The formation of new neurons is one component of plasticity; previous studies have shown that neuron growth in the hippocampus of healthy individuals can be stimulated by exercise. Frank-Gerald Pajonk, M.D., of The Saarland University Hospital, Homburg, and Dr. K. Fontheim's Hospital for Mental Health, Liebenburg, Germany, and colleagues assessed changes in hippocampal volume in response to an exercise program in both male patients with schizophrenia and men who had similar demographics and physical characteristics but did not have the condition.

Eight participants with schizophrenia and eight controls were randomly assigned to exercise (supervised cycling) three times per week for 30 minutes, whereas an additional eight patients with schizophrenia instead played tabletop football for the same period of time. The game enhances coordination and concentration but does not affect aerobic fitness. All participants underwent fitness testing, magnetic resonance imaging of the hippocampus, neuropsychological testing and other clinical measures before and after participating in the program for 12 weeks.

Following exercise training, hippocampal volume increased 12 percent in patients with schizophrenia and 16 percent in healthy controls. "To provide a context, the magnitude of these changes in volume was similar to that observed for other subcortical structures when patients were switched from typical to atypical antipsychotic drug therapy," the authors write. Conversely, patients with schizophrenia who played tabletop football instead of exercising experienced a 1 percent decrease in hippocampal volume.

Aerobic fitness also increased among all who exercised, and improvement in test scores for short-term memory was correlated with increases in hippocampal volume among patients and healthy controls.
"Further clinical studies are needed to determine if an incremental improvement in the disability related to schizophrenia could be obtained by incorporating exercise into treatment planning and lifestyle choice for individuals with the illness," the authors conclude.

Sources:  JAMA and Archives Journals  and  Hippocampal Plasticity in Response to Exercise in Schizophrenia

Stroke Patients Benefit From New Brain And Motor Skills Research

Bioengineers have taken a small step toward improving physical recovery in stroke patients by showing that a key feature of how limb motion is encoded in the nervous system plays a crucial role in how new motor skills are learned.

Published in a recent issue of Neuron, a Harvard-based study about the neural learning elements responsible for motor learning may help scientists design rehabilitation protocols in which motor adaptation occurs more readily, potentially allowing for a more rapid recovery.

Neuroscientists have long understood that the brain's primary motor cortex and the body's low-level peripheral stretch sensors encode information about the position and velocity of limb motion in a positively-correlated manner rather than as independent variables.

"While this correlation between the brain's encoding of the position and the velocity of motion is well-known, its potential importance and practical use has been unclear until now," says coauthor Maurice A. Smith, Assistant Professor of Bioengineering at the Harvard School of Engineering and Applied Sciences (SEAS) and the Center for Brain Science in the Faculty of Arts and Sciences.

Smith and colleagues showed that the correlated neural tuning to position and velocity is also present in the neural learning elements responsible for motor learning. Moreover, this correlated drive can explain key features of the motor adaptation process.

To study and record motor adaptation, the researchers had subjects grasp a robotic arm. The device was programmed to simulate novel physical dynamics as subjects made reaching motions. In addition, the team used a newly developed measurement technique called an "error-clamp" to tease apart the resulting data.

The method measures motor output during learning, allowing learning-related changes in motor output over the course of a movement to be dissociated from feedback adjustments that correct motor errors that happen simultaneously.

"Conceptually, this error-clamp is analogous to a voltage-clamp, commonly used in electrophysiology to measure how ions move through a neuron's membrane when it fires," explains lead author Gary C. Sing, a graduate student at SEAS. "The general idea is that devising an experimental method to clamp and control the key variable in an experiment can allow for greater insight into the underlying physiology."

Analysis of the data extracted by the error-clamp technique led to the creation of a computational model that identifies a set of vectors that characterize the principal components of motor adaptation in the state space of physical motion. While such analysis is commonplace in systems engineering -- for example, in evaluating how a bridge might react to high winds or earthquakes -- the method has only been recently applied to how motor output evolves.

"We observed that the initial stages of motor learning are often quick but non-specific, whereas later stages of learning are slower and more precise," says Sing. "Further, we saw that some physical patterns of movement are learned more quickly than others."

By understanding what types of motor adaptations are easier to learn, the researchers hope to design rehabilitation activities that will encourage patients to use an affected limb more.

"In stroke rehabilitation, patients who make a greater effort to use their impaired limbs can achieve better outcomes," says Smith. "However, there is often a vicious cycle, as a patient is far less likely to use an impaired limb if his or her other limb is fine. This pattern slows recovery and leads to greater impairment of the affected limb."

Smith and his colleagues are beginning studies with stroke patients to determine whether training them with such optimized patterns will, in fact, improve their rate of motor learning and speed up recovery.
More broadly, untangling the algorithms the brain uses for motor learning could help improve a wide range of neural and muscular rehabilitation programs. The researchers also anticipate that such findings could be one day be adapted for enhancing the brain/machine interfaces increasingly used for those with amputated limbs.

Sources:  Harvard University and "Primitives for Motor Adaptation Reflect Correlated Neural Tuning to Position and Velocity"

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?"

Sports Science Weekly Gym Bag - 10-28-09

Welcome to a World Series edition of the Weekly Sports Science Gym Bag, a collection of some of the best stuff I've found in the last week.  A few more baseball stories are included, while you watch the Yankees lose in 6 games!

The Overmanager: Why the New York Yankees' Joe Girardi is too smart for his own good
To play in the NFL, you have to make a show of going to college. To play in the NBA, you have to get through high school. To sign a contract with a major league baseball team, all you have to do is convince someone you're 16, provided you weren't born in a country with inconvenient labor laws. Perhaps this goes some way toward explaining both the high reverence in which the intellectual is held in baseball and the low standards necessary to qualify as one...

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

Phys Ed: Do More Bicyclists Lead to More Injuries?
Recently, surgeons and emergency room physicians at the Rocky Mountain Regional Trauma Center in Denver noticed a troubling trend. They seemed to be seeing cyclists with more serious injuries than in years past. Since many of the physicians at the hospital, a Level I trauma center serving the Denver metropolitan area, were themselves cyclists, they wondered if their sense of things was accurate.  So the doctors began gathering data on all cycling-related trauma admittances at the hospital and dividing them into two blocks, one covering 1995-2000 and the other 2001-6...

Football
In light of a recent post on the difficulty of changing our decision-making habits - even when we're aware that our habits are biased and flawed - I thought it might be interesting to look at two examples from professional football. Why sports? Given the intense competitive pressure in the NFL - there's a thin line between victory and ignominy - you'd expect head coaches to have corrected many of their decision-making mistakes, especially once those mistakes have been empirically demonstrated. But you'd be wrong. 
Consider some research done by David Romer, an economist at UC Berkeley, who published a 2001 paper entitled "Do Firms Maximize? Evidence From Professional Football". The question Romer was trying to answer is familiar to every NFL fan: what to do on 4th down? Is it better to bring on the kicking team for a punt or field-goal attempt? Under what conditions should coaches risk going for it?

Missed Kicks Make Brain See Smaller Goal Post
Flubbing a field goal kick doesn’t just bruise your ego — new research shows it may actually change how your brain sees the goal posts.  In a study of 23 non-football athletes who each kicked 10 field goals, researchers found that players’ performance directly affected their perception of the size of the goal: After a series of missed kicks, athletes perceived the post to be taller and more narrow than before, while successful kicks made the post appear larger-than-life.  Professional athletes have long claimed that their perception changes when they’re playing well — they start hitting baseballs as large as grapefruits, or aiming at golf holes the size of a bucket — but many scientists have been slow to accept that performance can alter visual perception...  

Baseball: Head-first Slide Is Quicker
Base running and base stealing would appear to be arts driven solely by a runner's speed, but there's more than mere gristle, bone and lung power to this facet of baseball -- lots of mathematics and physics are at play. Who gets there faster, the head-first slider or the feet-first?

Pump your arms to speed up your legs, thanks to “neural coupling”
“Keep pumping your arms!” That’s one of those canonical pieces of advice that it seems every coach gives to his or her runners. The idea is that, late in a run or race when your legs are burning and you’re starting to slow down, if you keep moving arms briskly, your legs will follow. It’s a nice idea — it’s always good to have some concrete piece of advice that you can hang onto when it seems like the world is about to explode. But does it work?
Unfortunately, I don’t know. But in the course of researching a completely different topic today, I stumbled on an interesting piece of research by Daniel Ferris, a University of Michigan researcher who’s best known for his research into assisted movement using robotic exoskeletons. The paper, which appeared in the journal Exercise and Sport Science Reviews back in 2006, is called “Moving the arms to activate the legs.” The full text is available here...

The Human Body Is Built for Distance
Does running a marathon push the body further than it is meant to go?  The conventional wisdom is that distance running leads to debilitating wear and tear, especially on the joints. But that hasn’t stopped runners from flocking to starting lines in record numbers.  Last year in the United States, 425,000 marathoners crossed the finish line, an increase of 20 percent from the beginning of the decade, Running USA says. Next week about 40,000 people will take part in the New York City Marathon. Injury rates have also climbed, with some studies reporting that 90 percent of those who train for the 26.2-mile race sustain injuries in the process...

Sports Science Weekly Gym Bag - 10-7-09

Time for another edition of the Sports Science Weekly Gym Bag. (Yes, a Wisconsin Badger football gym bag this week...they're 5-0!) If you ever run across something that you would like to share, just add it to the comments below!

Marathon Runners Mull the ‘D Word’
This is the time of year, after marathoners have logged their longest miles, that any kind of pain, nagging or excruciating, can send runners into a panic about whether they will make it to the starting line. Or if they should even try...

Faster tunes make you bike faster, even if it hurts a bit more
Researchers have been studying how music and other “distractions” affect exercise performance for decades (see here, for instance), hoping to trick us into pushing a little harder without realizing it. One of the factors they’ve looked at extensively is the speed of the music — the idea that faster tempos make us pick up the pace. The problem is that the effects of tempo tend to be swamped by the effect of whether the subjects in the experiment like the particular tunes selected for them...

How Do Marathons Affect Your Heart?
Last year the European Heart Journal published a study that continues to prompt discussion among researchers who work with marathoner runners and those, many of them the same researchers, who run marathons. In the study, German scientists scanned the hearts of 108 experienced, male distance runners in their fifties, sixties and seventies.  By standard measures, the group’s risk for heart problems was low. But when the researchers studied the runners’ scan results, they found that more than a third of the men showed evidence of significant calcification or plaque build-up in their heart arteries. Several also had scarring of some of the tissue in their hearts...

The Eyes Have It - Is visual training the sports world's next big thing?
Seattle Mariners first baseman Russell Branyan began this season on a tear. In interviews, Branyan credited his newfound success in large part to a piece of software that runs on an ordinary laptop. "I think it's helped me really pinpoint and focus on the ball," Branyan said of the Vizual Edge program, which offers a variety of exercises to train and sharpen visual skills. "I see the ball exactly where it is. I don't want to say it's all because of this. … But, I mean, I was a .230 hitter."

Watch Out Gatorade, Powerade, Accelerade! Mother Nature's Entered the Game!
"I'm convinced more than ever that Mother Nature is a runner. I've recently hailed Mother Nature's "natural sports drink"—coconut water—and its health benefits, especially how its naturally high level of potassium helps keep my calf cramps at bay on long runs. Well, it appears that Mother Nature has expanded her line of sports drinks..."

Young Athletes and Women More Likely to Have Second ACL Surgery Within a Year
According to one of the largest studies ever conducted on the outcomes of ACL surgery, patients under 40 and women are both more likely to have second knee surgery within a year of an ACL repair.  Investigators looked at surgical outcomes in 70,000 patients who had ACL reconstruction surgery from 1997 to 2006 in New York state. The results, published in the October 2009 issue of The Journal of Bone and Joint Surgery, found the following...

Despite Size, NFL Players Not More Likely To Develop Heart Disease, Even After Retirement
Former professional football players with large bodies don't appear to have the same risk factors for heart disease as their non-athletic counterparts, UT Southwestern Medical Center researchers have found in studying a group of National Football League (NFL) alumni....