On the Validity of Different Motion Capture Technologies for the Analysis of Running

An increasing diversity of available motion capture technologies allows for measurement of human kinematics in various environments. However, little is known about the differences in quality of measured kinematics by such technologies. Therefore, this work presents a comparison between three motion capture approaches, based on inertial-magnetic measurement units (processed with Xsens MVN Analyze) and optical markers (processed using Plug-In Gait and OpenSim Gait2392). It was chosen to evaluate the different motion capture approaches in running, as such kinematics are preferably measured in the natural running environment and involve challenging dynamics. An evaluation was done using data of 8 subjects running on a treadmill at three different speeds, namely 10, 12 and 14 kmlh. The sagittal plane results show excellent correlation $(\rho > \pmb{0.96})$ and RMSDs are smaller than 5 degrees for 6 out of the 8 subjects. However, results in the frontal and transversal planes were less correlated between the different motion capture approaches. This shows that sagittal kinematics can be measured consistently using any of the three analyzed motion capture approaches, but ambiguities exist in the analysis of frontal and transversal planes.