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SPEED-DEPENDENT INCREASE IN LUMBAR LORDOSIS IS INCONSISTENT WITH SPEED-INDEPENDENT PELVIC TILT DURING TREADMILL RUNNING
Get PDFLumbar lordosis (LL) is considered as an important factor of low back pain. Although LL during running (dynamic LL) and anterior pelvic tilt (APT) are thought to increase simultaneously, this relationship has not been examined when running speed is changed. Here we show that dynamic LL increases with the increase in running speed, whereas APT is invariant during treadmill running at 4.0, 5.5, 7.0 and 8.5 m/s in 18 male collegiate athletes. The speed-dependent increase in dynamic LL suggests that runners and coaches should be cautious that greater mechanical load on the lumbar spine might occur during faster running. The inconsistent sensitivity of the lumbar spine and the pelvis to the increase in running speed suggests that practitioners and clinicians should assess LL separately from APT, especially during faster running
FATIGUE-INDUCED CHANGES IN KNEE KINEMATICS AND MUSCLE FORCES IN PROFESSIONAL HANDBALL-SPECIFIC TASK
Get PDFThis study investigated the impact of fatigue on knee kinematics and muscle forces in female handball athletes performing sidestep-cutting manoeuvres. Twenty athletes completed six trials, each divided equally before and after a handball-specific fatigue protocol. Kinematic and kinect data were gathered using an infrared motion capture system and a force plate. Analysis was performed with OpenSim 3.3. The results were compared using statistical parametric mapping. They indicated significant fatigue-related decreases in knee flexion during the early stance phase, reduced activity in the vastus intermedius and medialis muscles. Therefore, the findings indorms the design of programs focused on improving muscle endurance; however, there is still no conclusive evidence linking fatigue to an increased risk of knee load
A SIMPLE JUMPING LANDING STABILITY ERRORS SYSTEM TO DIFFERENTIATE AND DIAGNOSE CHRONIC ANKLE INSTABILITY
Get PDFThis study investigates whether a simplified landing stability error system can differentiate individuals with chronic ankle instability (CAI). Fifteen CAI and fifteen healthy controls performed jumping landing tasks when instructed with the landing side before (planned) or after (unplanned) take-off. Landing errors were identified as the following criteria: (1) touching the ground with the free leg, (2) standing leg leaving the force plate after landing, (3) touching the ground with the hands, and (4) lateral deviation of sternum over hips. The CAI group had a higher total error (1.70±0.65 times/trial) compared to the normal group (0.89±0.58 times/trial), with a cut-off value of 1.37 times/trial, which provides a sensitivity of 78.6% and specificity of 88.9% in differentiating CAI. The simplified landing stability error system could be a promising method for differentiation and diagnosis of CAI
ANALYSING GAIT TRANSITION DYNAMICS IN UPHILL TRAIL RUNNING FROM WEARABLE DEVICES
Get PDFThis study investigates gait transition speed in trail running on uphill slopes using wearable devices data. It examines Preferred Transition Speed (PTS) and Heart Rate Optimal Transition Speed (HROTS), noting a decrease in both with increasing slope. This suggests an intuitive adaptation among athletes to lower speeds on steeper inclines, challenging the Iso-Efficient Speed concept and showing gait selection is influenced by more than energy efficiency. The analysis of data from 14 trail runners, aged 22-43 with at least one year of trail running experience, reveals distinct gait patterns characterized by a bimodal distribution in cadence and a unimodal distribution in stride length. These findings suggest that wearable technology not only can aid in analysing athletic performance in natural settings but could also lower the cost of monitoring gait transition parameters for trail runners
EFFECTS OF EXTENDED REALITY ON BIOMECHANICS AND REHABILITATION IN THE CONTEXT OF ACL INJURIES: A COMPREHENSIVE REVIEW
Get PDFThe review investigated Extended Reality (XR) applications in anterior cruciate ligament (ACL) injury risk screening and rehabilitation. Among 1135 studies, four met inclusion criteria. XR environments were investigated for their impact on knee biomechanics, attention, and proprioception. Findings revealed significant alterations in knee biomechanics induced by XR environments, including increased peak vertical ground reaction force and stiffer landings. XR immersion demonstrated altered movement strategies, hinting at potential distractions. While movements in XR and real environments were generally comparable, caution in approach velocity and differences in peak flexion angles suggested participant adaptations to virtual scenarios. While promising, further research is crucial for understanding long-term effects and practical clinical implementation
ASSESSING THE RELATIONSHIP BETWEEN CONTRALATERAL LIMB SYNERGY AND ROCK-CLIMBING EFFICIENCY
Get PDFThe purpose of this study was to determine the relationship between the continuous relative phase (CRP) of a rock-climbing move. Rock climbers (19) of varying years of experience, age, and gender attempted a competition-style bouldering problem as many times as possible in a given time frame. CRP angles were calculated for the left hip to right shoulder and left knee to right elbow and Geometric Entropy (GE) was calculated in 2 dimensions. CRP of shoulder to hip and elbow to knee joint angles showed no association with time to complete (TtC) and GE. There was a positive trend as blood lactate concentration (BLC) increased, and an increase in the Coefficient of Variation (COV) shoulder to hip CRP. Joint coordination is important to learning a skill and allowing for exploratory coordination and could be beneficial for the completion of a discrete climbing task
THE RELATIONSHIP BETWEEN NEUROCOGNITION AND SIDE-STEP CUTTING BIOMECHANICS IN WOMEN’S AUSTRALIAN FOOTBALL PLAYERS
Get PDFDespite increased awareness and targeted efforts, anterior cruciate ligament (ACL) injuries continue to frequently occur within the women’s Australian-rules football league (AFLW). AFLW ACL injuries frequently occur when performing a defensive side-step cut. Considering the reactive nature of this scenario, neurocognitive function may be an important risk factor. Therefore, the purpose of this study was to investigate the relationship between neurocognition and side-step cutting biomechanics in women’s Australian football players. Relationships between neurocognitive measures and 3D knee loads during unanticipated side-stepping were examined. No statistically significant relationships were found. These findings provide recommendations for future research to explore different cognitive parameters and ensure sufficient cognitive demand in the testing environment
KNEE JOINT MOMENTS DURING SPORTIVE CYCLING: A PILOT STUDY
Get PDFThis pilot study examines the impact of varying power outputs (157, 210, 262 W) and cadences (60, 80, 100 rpm) on knee joint kinetics in recreational cycling, aiming to understand the combined effects on knee moments across sagittal, frontal, and transverse planes. Conducted with two recreational cyclists, this full factorial study investigates mechanics through lower-body kinematics and pedal reaction forces. Results indicate varying knee joint moment patterns, especially an increasing external knee extension moment at higher power and cadence as well as a combined effect of both. The findings suggest an interaction between cadence, power output, cycling technique, and knee joint loading. However, limitations like the small sample size and participant performance level underline the need for more comprehensive research with a broader participant base
MODELLING OF SCAPULAR MOTION INFLUENCES THE ESTIMATED GLENOHUMERAL JOINT TORQUES DURING VOLLEYBALL HITTING
Get PDFThis study aims to understand how much different ways of modelling the scapular motion in musculoskeletal models influence the estimated inverse dynamics torques at the glenohumeral joint in simulations of volleyball hitting. We collected hitting motion data of one advanced volleyball player and compared the scapular motion and inverse dynamics torques at the glenohumeral joint estimated using three different musculoskeletal models that model the scapular motion in different ways. We found root mean squared differences of up to 50 Nm in inverse dynamics torques estimated from the different models and coupling between scapula and humerus can affect these estimates. Highest marker tracking errors were observed in the model with lowest number of independent scapular degrees of freedom suggesting scapular degrees of freedom should be carefully chosen
SENSOR-DRIVEN ANALYSIS OF ANGLE OF ATTACK IN ALPINE SKIING: A LABORATORY EXPLORATION
Get PDFThe aim was to address the absence of a universal measuring instrument for detecting the degree of carving or skidding in a ski turn. Sensors were employed to calculate the so-called angle of attack (θ), which increases if lateral skidding increases. A mathematical concept in 2D and 3D for sensor-based detection of the θ was developed and evaluated on a self-built centrifugal machine capable of executing both optimal carving as well as certain degrees of skidding. The variation of θ was systematically divided into the stages small, medium, and large. Each stage was further subdivided into three smaller levels to evaluate the discriminability of minor changes. Across all settings with different θ values, both 2D and 3D methods demonstrated precise recording and discrimination of subtle differences (1°-1.5°), as confirmed by 95%-Confidence Intervals