by Dennis Walikainen, senior editor
Do obese people avoid exercise because the equipment is not designed for them?
Does the pain or discomfort sometimes associated with exercise keep them from working out?
A Michigan Tech researcher is looking at how exercise equipment might be hindering workouts of the obese.
“I want to know if using this ergometer [rowing machines] leads to different movement kinematics and therefore joint loads, depending on body shape, for example,” says Karen Roemer, assistant professor of biomechanics in the exercise science, health and physical education department. “Potentially, we could give equipment manufacturers suggestions for new designs.”
Roemer is using some high-tech equipment for her research, and, thanks to a $26,700 grant from the Michigan Tech Research Excellence Fund, she will be able to do even more.
“We are using reflective markers [tiny sensor-balls] attached to the skin, then shooting them with multiple cameras,” she says. Similar to modeling Tiger Woods’ swing for a videogame, the many markers are translated via software that reproduces the movement.
“These are complex biomechanical problems,” Roemer says. “For modeling the knee joint, we used scans performed in an open MRI scanner and data from motion analysis using 80 reflective markers and 12 digital cameras.”
The result is a multi-body knee-joint model that looks like it came from the Matrix: complicated processes and images broken down by all the markers, then reassembled to resemble the real joint. And it takes time.
“Normally, digitizing one movement analyzed with video cameras can take six to eight weeks,” she said. “But with the new system in my lab I will be able to do it within a few days.”
Roemer did similar research in her native Germany at the Chemnitz University of Technology’s Department of Sport Science before coming to Tech. She also worked with the German national volleyball team. Based on motion analysis performed during European League games, the kinematics of fairly complicated joints, such as the shoulder, can be analyzed.
Other simulation studies allow for analyzing other aspects. For the stress on knees, for example, she tests on the rowing machine and stationary bike and while walking or running.
For gait and running analysis, a special force plate has been installed in Roemer’s new lab in the SDC. When the movement of a reflector-laden runner is captured crossing the plate, data can be gathered instantly into computers.
The three dimensions of the ground reaction force resulting from the foot hitting the floor, for example, are shown on the computer screen in red arrows shooting up through the person’s body.
She is also interested in daily movements, such as the gait, and what problems exist with joint loads, for example, that can be compared to more-intense movements.
All this time- and technology-intensive work is worth the wait, however, if it helps fight the weight.
