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• The vertical loading rate was not influenced by running mileages during half marathons. • Changes in coordination variabilities occurred at the early stance phase of running gaits. • As the half marathon progressed, coordination variabilities increased in the couplings of pelvis frontal vs. thigh frontal and shank transverse vs. rearfoot frontal. • The increased coordination variabilities on the frontal/transverse planes of motion could be associated with fatigue and indicate injury potential. Segment coordination variability (CV) is a movement pattern associated with running-related injuries. It can also be adversely affected by a prolonged run. However, research on this topic is currently limited. The purpose of this study was to investigate the effects of a prolonged run on segment CV and vertical loading rates during a treadmill half marathon. Fifteen healthy runners ran a half marathon on an instrumental treadmill in a biomechanical laboratory. Synchronized kinematic and kinetic data were collected every 2 km (from 2 km until 20 km), and the data were processed by musculoskeletal modeling. Segment CVs were computed from the angle-angle plots of selected pelvis-thigh, thigh-shank, and shank-rearfoot couplings using a modified vector coding technique. The loading rate of vertical ground reaction force was also calculated. A one-way MANOVA with repeated measures was performed on each of the outcome variables to examine the main effect of running mileage. Significant effects of running mileage were found on segment CVs (p ≤ 0.010) but not on loading rate (p = 0.881). Notably, during the early stance phase, the CV of pelvis frontal vs. thigh frontal was significantly increased at 20 km compared with the CV at 8 km (g = 0.59, p = 0.022). The CV of shank transverse vs. rearfoot frontal decreased from 2 km to 8 km (g = 0.30, p = 0.020) but then significantly increased at both 18 km (g = 0.05, p < 0.001) and 20 km (g = 0.36, p < 0.001). At the early stance, runners maintained stable CVs on the sagittal plane, which could explain the unchanged loading rate throughout the half marathon. However, increased CVs on the frontal/transverse plane may be an early sign of fatigue and indicative of possible injury risk. Further studies are necessary for conclusive statements in this regard. [Display omitted] [ABSTRACT FROM AUTHOR]

Objectives: To determine the concurrent validity of standard clinical outcome measures compared to laboratory outcome measure while performing the weight-bearing lunge test (WBLT).Design: Cross-sectional study.Methods: Fifty participants performed the WBLT to determine dorsiflexion ROM using four different measurement techniques: dorsiflexion angle with digital inclinometer at 15cm distal to the tibial tuberosity (°), dorsiflexion angle with inclinometer at tibial tuberosity (°), maximum lunge distance (cm), and dorsiflexion angle using a 2D motion capture system (°). Outcome measures were recorded concurrently during each trial. To establish concurrent validity, Pearson product-moment correlation coefficients (r) were conducted, comparing each dependent variable to the 2D motion capture analysis (identified as the reference standard). A higher correlation indicates strong concurrent validity.Results: There was a high correlation between each measurement technique and the reference standard. Specifically the correlation between the inclinometer placement at 15cm below the tibial tuberosity (44.9°±5.5°) and the motion capture angle (27.0°±6.0°) was r=0.76 (p=0.001), between the inclinometer placement at the tibial tuberosity angle (39.0°±4.6°) and the motion capture angle was r=0.71 (p=0.001), and between the distance from the wall clinical measure (10.3±3.0cm) to the motion capture angle was r=0.74 (p=0.001).Conclusions: This study determined that the clinical measures used during the WBLT have a high correlation with the reference standard for assessing dorsiflexion range of motion. Therefore, obtaining maximum lunge distance and inclinometer angles are both valid assessments during the weight-bearing lunge test. [ABSTRACT FROM AUTHOR]

At first sight, shoulder mobility is frequently evaluated through mono-axial amplitude. Interestingly, for diagnosing shoulder hyperlaxity or frozen shoulder, external rotation of the arm whilst at the side (ER1) is commonly used. However, by definition, a mono-axial amplitude does not fully reflect shoulder global mobility. Our goal was to propose a novel index for measuring shoulder global mobility and secondly to evaluate the link between main mono-axial amplitudes and this new index. Twenty-eight female subjects (mean age 24.8 years) without upper limb pathology participated in the study. The movements of their right dominant arm were measured with an opto-electronic motion capture system. They performed 5 mono-axial maximal amplitude motions (axial rotations in three different postures, flexion/extension and abduction from rest) and a global range of motion exploring all the reachable space around the three axes of rotation. From this, we computed the correlation coefficient between the volume of the reachable space and each possible linear combination of the 5 mono-axial amplitudes. Even though ER1 is often chosen to assess global mobility, it demonstrated the lowest correlation with measured joint mobility. To assess shoulder global mobility, clinical routine examination should more take into account external/internal rotation with the shoulder abducted, then abduction and finally flexion/extension. However, further clinical testing in other populations has to be done to evaluate the potential generalization of this result. [ABSTRACT FROM AUTHOR]