RU faculty researchers examine muscle fatigue in Paralympic athletes


Sample placement of EMG electrodes on Jason Regier

Wheelchair athletes suffer tremendous strain on their shoulders and other upper-body muscles during competitions and training. They are constantly at risk to injuries that could negatively impact their future athletic performances and possibly limit their personal mobility and independence.

Under the direction of the U.S. Paralympic Research and Sports Science Consortium, three Radford University faculty members are studying fatigue patterns associated with gameplay and training movements of the athletes in hopes of helping trainers and coaches develop better conditioning routines that limit these risks.

J.P. Barfield, Laura Newsome and David Sallee, faculty members in RU's Department of Health and Human Performance, began the study during the summer with the U.S. Men's Paralympic Rugby team to examine, through electromyography (EMG), the game play movements of the athletes and to determine fatigue patterns of various shoulder movements.

The RU researchers closely examined how the athletes compensate for muscle fatigue as their activity progressed.

"There's not nearly enough research for Paralympic athletes as there is for able-body athletes," Barfield said. "Able-bodied athletes use their legs, whereas wheelchair athletes have a lot of stress on their shoulders. They're moving a lot of mass with a much smaller muscle group. So, the injury risk is a lot higher, and one way to combat that is to make sure you're training them properly."

Barfield, a member of the Research and Sports Science Consortium, the research branch of the U.S. Paralympic Committee, said this new research will help identify where fatigue has occurred when Paralympic athletes use secondary muscles.

"Most fatigue studies look at continuous wheelchair pushing, but that's not how wheelchair rugby is played," Barfield said. "When muscular activity changes, we can get a sense of fatigue and how the athletes begin to compensate by using secondary muscles. That's when their injury risk increases."


Left to right: Chuck Melton, Laura Newsome, JP Barfield, Derrick Helton, Steve Pate, Jason Regier, and Emmanuel John

To conduct the study, the three researchers placed EMG sensors on the rugby players during one of the national team's eight annual training camps. EMG assessment allows researchers to measure the electrical activity of skeletal muscle, thereby determining muscle changes during live events.

"On one day, we would measure three prime movers, and on another day we would measure four other muscles involved with movement," Barfield said. "We would measure minute intervals about every 10 or 15 minutes."

Barfield, Newsome and Sallee did this while the team scrimmaged and did sprints and agility work on a basketball court, where wheelchair rugby is played. The training sessions were two- to three-hour blocks, and the researchers measured eight to 10 activities from beginning to end.

The research began when the U.S. Paralympic Committee accepted a proposal from the RU faculty members to study the topic, one of only two accepted during 2014. From there, the three traveled to Alabama to begin working with the rugby team at the Lakeshore Foundation training facility.

The study yielded a large amount of data, which is still being processed. Once the numbers are examined, the findings could "help us learn to reduce injury risk among Paralympic athletes," Barfield said. "I think the research will have great importance in disability sports."

Oct 7, 2014