Reliability of Xsens IMU-Based Lower Extremity Joint Angles during In-Field Running

Abstract

The Xsens Link motion capture suit has become a popular tool in investigating 3D running kinematics based on wearable inertial measurement units outside of the laboratory. In this study, we investigated the reliability of Xsens-based lower extremity joint angles during unconstrained running on stable (asphalt) and unstable (woodchip) surfaces within and between five different testing days in a group of 17 recreational runners (8 female, 9 male). Specifically, we determined the within-day and between-day intraclass correlation coefficients (ICCs) and minimal detectable changes (MDCs) with respect to discrete ankle, knee, and hip joint angles. When comparing runs within the same day, the investigated Xsens-based joint angles generally showed good to excellent reliability (median ICCs > 0.9). Between-day reliability was generally lower than the within-day estimates: Initial hip, knee, and ankle angles in the sagittal plane showed good reliability (median ICCs > 0.88), while ankle and hip angles in the frontal plane showed only poor to moderate reliability (median ICCs 0.38–0.83). The results were largely unaffected by the surface. In conclusion, within-day adaptations in lower-extremity running kinematics can be captured with the Xsens Link system. Our data on between-day reliability suggest caution when trying to capture longitudinal adaptations, specifically for ankle and hip joint angles in the frontal plane.

IMU Data‐Driven and PCA‐Based Approach to Establish Quantifiable and Practically Applicable Measures for V2 Technique Elements in Cross‐Country Skiing

“…The relevant PMs for ski set-down and leg push-off instructions (Figure 5c,d) were selected based on the animated stick figure representations, that showed leg strategies involving knee adduction and abduction. The two extreme PP waveforms were not distinguishable, which might be explained by the fine level of detail of these movements and thus difficulties in capturing them by the used measurement equipment [38]. Probably more sensors at the feet or additionally on the skis would be necessary to gain more insights into the detailed ski-snow contact movements.…”

“…Measures for lateral tilt, plantar flexion, ski set-down and leg push-off proved to be not sensitive. Likely reasons for this lack of sensitivity were, on the one hand, shortcomings in the sensor hardware setup for small movements in the frontal plane [38], and on the other hand, the reference frame in which the data were presented as PCA input.…”

Spatiotemporal parameters and kinematics differ between race stages in trail running—a field study

“…IMU sensors were located on: head, shoulders (2 ), arms (2 ), forearms (2 ), thighs (2 ), legs (2 ), feet (2 ), sternum and pelvis. Previous studies validated such system against gold standard marker-based methods, reporting reliable and consistent results for tasks such as running and changes of directions on both asphalt and irregular surfaces [ 13 – 16 ]. All subjects wore the equipment approximately 30 min before the beginning of the trial, thus having enough time to become accustomed with the suit and the wearables.…”