Back pain influenced by heavy backpack carriage, in youth especially, is a common issue. Companies have introduced backpacks with ergonomic features to ease the stress on consumers’ backs, but the success of these added features is questionable.
Following a six-week study in the Summer Research Scholars Program, Ryan Queen, senior health studies, pre-physical therapy and strength and conditioning major, found that more expensive, ergonomic backpacks may not be worth the extra cost.
Prior to taking a biomechanics course led by Ed Nyman Jr., Ph.D., assistant professor of health and human performance, Queen hadn’t put much thought into conducting research focused in biomechanics. It was after completing that course that Queen decided he wanted to participate in the Summer Research Scholars Program and be mentored by Nyman and Guofen Yu, Ph.D., associate professor of physics and chair of physical sciences.
“Most professional program students have little to no experimental research experience which can stifle their research opportunities in grad school,” said Nyman. “Programs such as this help break down that barrier and open doors to greater graduate-level research opportunities.”
When seeking a research topic within biomechanics, Queen found backpack carriage to be a perfect fit as it’s something that he and his peers experience every day.
“Primarily, we looked at the biomechanical load of different backpack systems,” Queen explained. “In the secondary part of the project, we looked at energy produced by backpacks in motion.”
With six human subjects, Queen took baseline measurements including height and weight, then used six 3D infrared motion cameras to assess the subjects with each backpack. In a randomized order, Queen evaluated each subject as they walked with no backpack, with a standard backpack and with an ergonomic backpack. The backpacks contained 15 percent of the subject’s bodyweight which is the weight where postural changes often start to occur. During the assessment, Queen measured four variables including sagittal plane hip moment, frontal plane hip moment, peak ground reaction forces and trunk forward lean.
“Out of the four variables, only the trunk forward lean variable had a significant difference,” said Queen. “But, the fact that the rest of the variables had no significant differences means something too since the ergonomic backpack is supposed to be better.”
Although it is common for individuals to lean forward when carrying a backpack, Queen’s results showed that both backpack designs caused an equal amount of trunk forward lean meaning that the ergonomic backpack did not prove to be any better than the standard design.
With data derived from the initial research, Queen wanted to determine the amount of energy available from backpacks as they are used in gait or movement. He explained that if enough energy is available, backpacks may be able to charge cell phones, laptops, or iPads in the future.
“We wanted to look at the energy that is available by backpacks in motion,” said Queen. “I found it really interesting that there is potential for energy to be harnessed just from the motion of your backpack as it moves up and down.”
After testing, Queen found an average of 29.6 watts of available power in the standard backpack design and an average of 34.6 watts in the ergonomic design. He said that the difference in values were likely due to the constructions of the backpack system straps.
According to Queen, charging a cell phone may be doable at this level of power over time. However, he plans to further this research to determine how the energy can be better harnessed for beneficial purposes.
“From all of it, I think that the issue is that all backpacks that we wear today are posteriorly loaded, which is going to change your center of mass,” said Queen. “There is a solution, but it’s not practical for students because it doesn’t look anything like what we wear now. It’s a vest with pouches on each side called the BackTpack and it’s already endorsed by the American Physical Therapy Association.”
Although his research isn’t complete just yet, Queen looks forward to more research opportunities ahead. He found that learning how to complete the Institutional Review Board (IRB) process to utilize human subjects and conducting real research with the guidance of his mentors to be incredibly beneficial as he prepares for graduate school in the future.
“The mentors really help you through the project and make you feel like you’re in the driver’s seat,” he said. “They make sure you do everything correctly but let you take the project where you want it to go.”
For more information about the Summer Research Scholars Program, contact Dr. Edward Nyman Jr. at 419-434-5969 or firstname.lastname@example.org.