Recovery reversal seen in Oregon study of returning concussed athletes

August 20, 2014
Li-Shan Chou, a professor of human physiology, directed research that measured the gait and cognitive skills, separately and combined, to study the impacts of concussions on high school athletes. While athletes showed recovery initially, many who returned to action in less than a month showed a regression in their abilities to dual task. Credit: University of Oregon

When are athletes who have suffered concussions ready to return to action? A new University of Oregon study has found that high school athletes who head back on the field with medical clearance within 60 days experience a significant regression in their abilities to simultaneously walk and do simple mental tasks.

The regression, as seen in changes in their and/or altered walking speed, was found in 12 of 19 . Ten of the 12 had returned to activity in less than a month. Seven athletes, who performed similarly to uninjured , had returned to action more than 20 days after their injuries. The athletes included 13 from football, four from soccer and one each from wrestling and volleyball.

The findings, published with the results presented more generally, were placed online ahead of print in the journal Medicine & Science in Sports & Exercise. The conclusions emerged after a closer examination of data detailed in an earlier study in the same journal in 2013. That study showed that 25 concussed high-school athletes had compromised abilities to focus and switch tasks for up to two months after their injuries. Assessments were done within 72 hours of and one week, two weeks, a month and two months later. Six of the athletes did not return to action in the study period and were excluded in the new analysis.

In the course of the original research, the athletes reported on when they had been cleared to resume practicing. At 28 days post injury, data suggesting a regression began to emerge, said principal investigator Li-Shan Chou, a professor in the UO Department of Human Physiology and director of the Motion Analysis Laboratory.

"We had seen this same type of curve in an earlier study of college athletes," he said. "We didn't have any evidence linking it to a return to activity, but we did discuss that possibility, because we knew that they usually were permitted to return to practice two weeks after a ."

The current practice for allowing most athletes to return to activity is mostly based on self-reports of symptoms and individual assessments of cognition or motor function.

The video will load shortly.
Li-Shan Chou provides a short summary of the findings.

For the new analysis, lead author David Howell, who received a doctoral degree at the UO in June and is now at Boston Children's Hospital, confirmed with medical staff and team trainers when the athletes had returned to activity. He focused on these athletes' individual data, comparing their return-to-activity status with the results of three tests: simply walking; separately doing simple computerized mental exercises; and a combination in which they walked and performed mental exercises simultaneously.

"There had been a continuous improvement prior to the athletes' return to activity," Chou said. "But at the data point taken after their return to activity, we saw a turn in their recovery in the opposite direction. When the athletes did a simple walking test, there was no regression. Just using the computer task to probe their cognitive functioning, we didn't see a regression. However, put together, we did."

In the dual task exercise, the athletes, while walking, heard a spoken word and identified whether it was delivered in a low- or high-pitched tone. In other variations, the subjects' were told, as they began walking, to recite months backward from October or subtract 7 repeatedly, beginning from 100.

The more complex a secondary task the greater the effect on a concussed individual than a non-injured control subject, Chou said. The earlier published study had found slowed reaction time of 30 to 40 milliseconds among concussed athletes two months after injury. "For many of us, that is just a blink of the eyes, but for athletes to be sure their bodily position is ready to perform a very skillful avoidance maneuver or prepare to safely take a collision, 30 milliseconds is a critical length of time for assuming that posture," he said.

Control subjects were healthy individuals of the same sex, body size, age and sport of the injured athletes. The research focused on frontal regions of the brain responsible for working, or short-term, memory and executive function.

Explore further: Intercollegiate contact athletes with shoulder instability return to in-season sports

Related Stories

Intercollegiate contact athletes with shoulder instability return to in-season sports

July 10, 2014
College athletes experiencing in-season shoulder instability regularly return to play within one week of injury, but developed recurrent instability in 63% of cases, according to research presented today at the American Orthopaedic ...

The concussed brain at work: fMRI study documents brain activation during concussion recovery

August 19, 2013
For the first time, researchers have documented irregular brain activity within the first 24 hours of a concussive injury, as well as an increased level of brain activity weeks later—suggesting that the brain may compensate ...

College athletes often sidelined from healthy lifestyle later in life

March 3, 2014
An Indiana University study found that elite college athletes—typically the picture of health and vitality—often struggle to stay active in later years, facing limitations to their day-to-day activities in middle age ...

Cognitive deficits from concussions still present after two months

January 7, 2013
The ability to focus and switch tasks readily amid distractions was compromised for up to two months following brain concussions suffered by high school athletes, according to a study at the University of Oregon.

Simple test helps doctors catch more concussions on the field

July 28, 2014
On the football field, sometimes the signs of a concussion are subtle. A player may have taken a tough hit but isn't showing symptoms yet, and either doesn't notice anything is wrong or won't report it for fear of being taken ...

More high school athletes complying with concussion guidelines, study finds

April 10, 2014
(HealthDay)—High school athletes who suffer from concussions are complying more with the recommended return-to-play guidelines, according to new research.

Recommended for you

To reduce postoperative pain, consider sleep—and caffeine

August 18, 2017
Sleep is essential for good mental and physical health, and chronic insufficient sleep increases the risk for several chronic health problems.

Despite benefits, half of parents against later school start times

August 18, 2017
Leading pediatrics and sleep associations agree: Teens shouldn't start school so early.

Doctors exploring how to prescribe income security

August 18, 2017
Physicians at St. Michael's Hospital are studying how full-time income support workers hired by health-care clinics can help vulnerable patients or those living in poverty improve their finances and their health.

Schoolchildren who use e-cigarettes are more likely to try tobacco

August 17, 2017
Vaping - or the use of e-cigarettes - is widely accepted as a safer option for people who are already smoking.

Federal snack program does not yield expected impacts, researchers find

August 17, 2017
A well-intentioned government regulation designed to offer healthier options in school vending machines has failed to instill better snacking habits in a sample of schools in Appalachian Virginia, according to a study by ...

Study shows cigarette makers shifted stance on nicotine patches, gum

August 17, 2017
The use of nicotine patches, gum, lozenges, inhalers or nasal sprays—together called "nicotine replacement therapy," or NRT—came into play in 1984 as prescription medicine, which when combined with counseling, helped ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.