Running Shoes May Increase Lower Joint Torques
Disproportionately large increases observed for hip and knee torque
FRIDAY, Jan. 8 (HealthDay News) -- Compared to running barefoot, running in running shoes substantially increases hip and knee torque, according to a study in the December issue of Physical Medicine & Rehabilitation.
D. Casey Kerrigan, M.D., of JKM Technologies in Charlottesville, Va., and colleagues conducted a study of 68 healthy young adult runners who reported usually using running shoes. The researchers collected three-dimensional motion capture data as the runners used an instrumented treadmill at a controlled running speed. All runners ran on the treadmill barefoot and in the same type of stability running shoe. The researchers calculated external joint torques at the hip, knee and ankle.
The data collected during running in the shoes showed that, compared to running barefoot, torques increased at the hip, knee and ankle. Hip internal rotation torque increased by an average of 54 percent, while knee flexion torque and knee varus torque increased by an average of 36 and 38 percent, respectively, the researchers found.
"These findings confirm that one effect of the typical construction of modern-day running shoes is to increase joint torques at each of the three lower extremity joints. These increases are likely caused in large part by an elevated heel and increased material under the medial aspect of the foot," the authors write. "The development of new footwear designs that encourage or mimic the natural compliance that normal foot function provides while minimizing knee and hip joint torques is warranted."
Kerrigan developed patented footwear design used by JKM Technologies and the OESH brand.