Synchronised Video, Motion Capture and Force Plate Dataset for Validating Markerless Human Movement Analysis.

The BioCV dataset is a unique combination of synchronised multi-camera video, marker based optical motion capture, and force plate data, observing 15 healthy participants (7 males, 8 females) performing controlled and repeated motions (walking, running, jumping and hopping), as well as photogrammetry scan data for each participant. The dataset was created for the purposes of developing and validating the performance of computer vision based markerless motion capture systems with respect to marker based systems.

Implementation of a passive bi-articular ankle-knee exoskeleton during maximal squat jumping.

Owing to the unexplored potential to harness knee extension power during jumping, the current study aimed to examine how joint mechanics were altered with a biologically inspired, passive bi-articular ankle-knee exoskeleton, which could potentially facilitate greater jump height by increasing work production about the knee and ankle. Twenty-five participants (16 males and 9 females, 175.2 ± 8.

Seasonal Muscular Power Changes: Considerations of Concurrent Resistance and Field-Based Training in Professional Rugby League.

Redman, KJ, Wade, L, Whitley, R, Connick, MJ, Kelly, VG, and Beckman, EM. Seasonal muscular power changes: considerations of concurrent resistance and field-based training in professional rugby league. J Strength Cond Res 38(9): 1620-1626, 2024-A rugby league player's ability to develop or maintain lower-body power will be significantly influenced by the resistance and field-based training loads completed.

Automating Video-Based Two-Dimensional Motion Analysis in Sport? Implications for Gait Event Detection, Pose Estimation, and Performance Parameter Analysis.

Background: Two-dimensional (2D) video is a common tool used during sports training and competition to analyze movement. In these videos, biomechanists determine key events, annotate joint centers, and calculate spatial, temporal, and kinematic parameters to provide performance reports to coaches and athletes. Automatic tools relying on computer vision and artificial intelligence methods hold promise to reduce the need for time-consuming manual methods.

The effect of foot orientation modifications on knee joint biomechanics during daily activities in people with and without knee osteoarthritis.

Background: Altered gait could influence knee joint moment magnitudes and cumulative damage over time. Gait modifications have been shown to reduce knee loading in people with knee osteoarthritis during walking, although this has not been explored in multiple daily activities. Therefore, this study investigated the effect of different foot orientations on knee loading during multiple daily activities in people with and without knee osteoarthritis.

The effectiveness of a 6-week biofeedback gait retraining programme in people with knee osteoarthritis: protocol for a randomised controlled trial.

Background: Gait retraining is a common therapeutic intervention that can alter gait characteristics to reduce knee loading in knee osteoarthritis populations. It can be enhanced when combined with biofeedback that provides real-time information about the users' gait, either directly (i.e.

The development and evaluation of a fully automated markerless motion capture workflow.

This study presented a fully automated deep learning based markerless motion capture workflow and evaluated its performance against marker-based motion capture during overground running, walking and counter movement jumping. Multi-view high speed (200 Hz) image data were collected concurrently with marker-based motion capture (criterion data), permitting a direct comparison between methods. Lower limb kinematic data for 15 participants were computed using 2D pose estimation, our 3D fusion process and OpenSim based inverse kinematics modelling.

Walking with increasing acceleration is achieved by tuning ankle torque onset timing and rate of torque development.

Understanding the mechanics of torque production about the ankle during accelerative gait is key to designing effective clinical and rehabilitation practices, along with developing functional robotics and wearable assistive technologies. We aimed to explore how torque and work about the ankle is produced as walking acceleration increases from 0 to 100% maximal acceleration. We hypothesized that as acceleration increased, greater work about the ankle would not be solely due to ramping up plantar flexor torque, and instead would be a product of adjustments to relative timing of ankle torque and angular displacement.

Backward Double Integration is a Valid Method to Calculate Maximal and Sub-Maximal Jump Height.

The backward double integration method uses one force plate and could calculate jump height for countermovement jumping, squat jumping and drop jumping by analysing the landing phase instead of the push-off phase. This study compared the accuracy and variability of the forward double integration (FDI), backwards double integration (BDI) and Flight Time + Constant (FT+C) methods, against the marker-based rigid-body modelling method. It was hypothesised that the jump height calculated using the BDI method would be equivalent to the FDI method, while the FT+C method would have reduced accuracy and increased variability during sub-maximal jumping compared to maximal jumping.

Applications and limitations of current markerless motion capture methods for clinical gait biomechanics.

Background: Markerless motion capture has the potential to perform movement analysis with reduced data collection and processing time compared to marker-based methods. This technology is now starting to be applied for clinical and rehabilitation applications and therefore it is crucial that users of these systems understand both their potential and limitations. This literature review aims to provide a comprehensive overview of the current state of markerless motion capture for both single camera and multi-camera systems.

Effects of the Off-Season on Muscular Power in Professional Rugby League.

Purpose: Periods away from training and competition are necessary for physical and mental restoration in sport. There is limited research investigating changes to physical qualities in rugby league following prolonged breaks. This study aimed to evaluate the effects of the off-season on muscular power in rugby league.

Predicting Rugby League Tackle Outcomes Using Strength and Power Principal Components.

Purpose: Tackling is a fundamental skill in collision sports such as rugby league. Given the complexity of tackling and multitude of strength and power variables available for analysis, this study aimed to predict tackle outcomes in professional rugby league based on strength and power principal components (PCs).

Methods: Twenty-eight rugby league players participated in this study.

The accuracy of several pose estimation methods for 3D joint centre localisation.

Human movement researchers are often restricted to laboratory environments and data capture techniques that are time and/or resource intensive. Markerless pose estimation algorithms show great potential to facilitate large scale movement studies 'in the wild', i.e.

A novel IMU-based clinical assessment protocol for Axial Spondyloarthritis: a protocol validation study.

Clinical assessment of spinal impairment in Axial Spondyloarthritis is currently performed using the Bath Ankylosing Spondylitis Metrological Index (BASMI). Despite being appreciated for its simplicity, the BASMI index lacks sensitivity and specificity of spinal changes, demonstrating poor association with radiographical range of motion (ROM). Inertial measurement units (IMUs) have shown promising results as a cost-effective method to quantitatively examine movement of the human body, however errors due to sensor angular drift have limited their application to a clinical space.

The Relationship Between Match Tackle Outcomes and Muscular Strength and Power in Professional Rugby League.

Redman, KJ, Wade, L, Whitley, R, Connick, MJ, Kelly, VG, and Beckman, EM. The relationship between match tackle outcomes and muscular strength and power in professional rugby league. J Strength Cond Res 36(10): 2853-2861, 2022-Tackling is a fundamental skill in collision sports, such as rugby league.

Joint and muscle-tendon coordination strategies during submaximal jumping.

Previous research has demonstrated that during submaximal jumping humans prioritize reducing energy consumption by minimizing countermovement depth. However, sometimes movement is constrained to a nonpreferred pattern, and this requires adaptation of neural control that accounts for complex interactions between muscle architecture, muscle properties, and task demands. This study compared submaximal jumping with either a preferred or a deep countermovement depth to examine how joint and muscle mechanics are integrated into the adaptation of coordination strategies in the deep condition.

Comparisons of laboratory-based methods to calculate jump height and improvements to the field-based flight-time method.

Laboratory methods that are required to calculate highly precise jump heights during experimental research have never been sufficiently compared and examined. Our first aim was to compare jumping outcome measures of the same jump, using four different methods (double integration from force plate data, rigid-body modeling from motion capture data, marker-based video tracking, and a hybrid method), separately for countermovement and squat jumps. Additionally, laboratory methods are often unsuitable for field use due to equipment or time restrictions.

The influence of added mass on muscle activation and contractile mechanics during submaximal and maximal countermovement jumping in humans.

Muscle contractile mechanics induced by the changing demands of human movement have the potential to influence our movement strategies. This study examined fascicle length changes of the triceps surae during jumping with added mass or increasing jump height to determine whether the chosen movement strategies were associated with relevant changes in muscle contractile properties. Sixteen participants jumped at sub-maximal and maximal intensities while total net work was matched via two distinct paradigms: (1) adding mass to the participant or (2) increasing jump height.

Movement Strategies for Countermovement Jumping are Potentially Influenced by Elastic Energy Stored and Released from Tendons.

The preferred movement strategies that humans choose to produce work for movement are not fully understood. Previous studies have demonstrated an important contribution of elastic energy stored within the Achilles tendon (AT) during jumping. This study aimed to alter energy available for storage in the AT to examine changes in how jumpers distribute work among lower limb joints.