This study provides some insight into potential mechanisms by which an eccentric hamstring exercise programme utilizing the NHE as the mode of exercise may result in an improvement in hamstring muscle control during eccentric contractions.

Dynamic postural stability was adversely affected immediately after cryotherapy to the ankle joint.

Marker-less motion capture systems can provide online recordings of human biomechanics during rapid dynamic exercises such as countermovement jump (CMJ) which could indicate an athlete's risk of injury to the anterior cruciate ligament (ACL). However, without additional postprocessing the localisation accuracy of the joints can be insufficient. Subsequently, biomechanics measurements, e.g. knee flexion angles, can be severely corrupted. We propose a calibration algorithm to correct for deviations in the bone length during CMJ as recorded by a low cost marker-less motion capture system (i.e. Kinect, version 2). Results were compared to gold standard VICON measurements. In this single subject study of three CMJs the accuracy of the measured knee flexion angle during stabilisation (post jump) was significantly improved from -9.6° to -3.8° (p<0.05) for the left knee, and from -5.0° to 1.7° (p<0.05) for the right knee. In conclusion, bone-length calibration and correction may enhance the joint localisation accuracy for low cost marker-less motion capture to the extend where clinically-relevant decisions can be facilitated.

ABSTRACT:The aim of the study was to perform a preliminary validation of a low cost markerless motion capture system (CAPTURE) against an industry gold standard (Vicon). Measurements of knee valgus and flexion during the performance of a countermovement jump (CMJ) between CAPTURE and Vicon were compared. After correction algorithms were applied to the raw CAPTURE data acceptable levels of accuracy and precision were achieved. The knee flexion angle measured for three trials using Capture deviated by -3.8° ± 3° (left) and 1.7° ± 2.8° (right) compared to Vicon. The findings suggest that low-cost markerless motion capture has potential to provide an objective method for assessing lower limb jump and landing mechanics in an applied sports setting. Furthermore, the outcome of the study warrants the need for future research to examine more fully the potential implications of the use of low-cost markerless motion capture in the evaluation of dynamic movement for injury prevention.