Athletes Flip for Motion Analysis


From left, Assistant Professor of Physical Therapy and Health Science Joe Kelly and second-year DPT students John Zegar and Joe Oloffson discuss research using a camera and Dartfish software to determine
if the new technique is safer. 

Flipping an oversized tire weighing as much as 500 pounds has become a popular exercise among athletes. Now, the workout technique is the subject of a research project for two students in Bradley’s Doctorate of Physical Therapy (DPT) program. Incorporating Dartfish motion analysis software, the students’ research compares the stance typically used when flipping tires to an alternate stance developed by Bradley alumnus Joe Terry. 

The owner of the Human Performance Lab in Metamora, Ill., Terry hopes the research will show that the method he advocates for flipping tires is safer than the technique commonly used. Terry had attended a continuing education course at Bradley in which physical therapy graduates were encouraged to submit research ideas. “As clinicians in the field, we were asked what questions we have that aren’t being answered,” Terry said, noting he brought the research idea to Physical Therapy and Health Science Assistant Professor Joe Kelly.

“Evidence-based clinical practice begins with researching current trends,” Kelly said. “Fresh ideas from clinicians, such as Joe Terry, create wonderful learning opportunities for our DPT students. Clinical research is a strong thread in the DPT curriculum, and our students are expected to complete a research project with the assistance of a faculty member. The bar is set high with the expectation to disseminate their findings at either a state or national level. In fact, 12 students from the third-year class presented their research in February at the APTA Combined Sections Meeting in Las Vegas, the most well-attended conference for the profession of physical therapy.” 

An Innovative Approach

Joe Oloffson and John Zegar, both second-year students in the three-year DPT program, have undertaken Terry’s proposed research project. Using a high-speed camera, they took videos of 18 athletes using two tire-flipping methods. “With Dartfish video technology, we are analyzing joint angles used during lifts,” Zegar said. “We can see the amount of angular velocity athletes are able to produce during lifts and can determine the effectiveness of the lifts. We are working from the hypothesis that the technique that produces more angular velocity is better. We’re also looking at whether one technique is safer than the other.”

Oloffson and Zegar are sifting through data and making correlations. “We are trying to paint a picture, and right now, we don’t know what it will look like,” Oloffson said. “We’re hoping to learn which is the best form with the least possibility of incurring injury and which is best for strength and conditioning.”

The students noted Dartfish video technology has many applications in educational, corporate and individual settings. For instance, it is used during Olympics coverage to show two athletes on an overlapping screen as they progress through a competition such as skiing. In some running stores, customers are videotaped running, so they can buy the shoes that fit their running styles. The software can be used in coaching, sports performance and physical therapy applications.

An Undergraduate Advantage

Kelly also uses Dartfish when teaching a motion analysis class, the final course for health science majors. “In health science, we look at human movement as being a biological marker to health,” Kelly said. “How well we move reflects how well we manage our day-to-day activities or how we can perform from an athletic perspective.”

Using their cell phone cameras, students can take videos of people engaging in large, dynamic movements such as swinging a baseball bat or a tennis racquet, or punting a football. “Students can compare a novice and an expert,” Kelly added. “They can look at differences in technique by comparing angles and postures.”

Students analyze the videos, watching for indicators such as a weakness in a muscle group. “We can see impairments in technique and connect that to exercise to help correct the faulty movement. On a larger scale, it’s what we would instruct for physical therapy students,” Kelly said.

Kelly began using Dartfish in undergraduate and graduate classes in spring 2012 with positive response. While the software has been available commercially for several years, it entered academia toward the end of 2011. 

“This is a fresh approach,” Kelly noted. “Students can have access on their personal laptops, which takes the learning opportunity out of the classroom. I am pleased by our students’ acceptance of it. We are using equipment at the undergraduate level that is usually utilized only at the graduate level.”  

By Nancy Ridgeway
Photography by Duane Zehr

Mike Holloway, a second-year student in Bradley’s Doctorate of Physical Therapy (DPT) program and a strength and conditioning coach, demonstrates a new method for flipping tires developed by alumnus Joe Terry. A motion analysis of the method is described on the photos.