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MACHINE LEARNING APPROACHES FOR IDENTIFICATION OF PARKINSON’S DISEASE SEVERITY USING MULTIMODAL FEATURES
Get PDFThis study aimed to create a digital biomarker for assessing the severity of Parkinson\u27s disease (PD) using multimodal features from 50 PD patients and 50 healthy controls. They underwent clinical tests, gait analysis using a motion capture system, postural and functional evaluations, and lifestyle questionnaires. These multimodal features underwent dimensionality reduction techniques such as logistic regression and principal component analysis to identify PD severity using the MDS-UPDRS total score. The results developed six models using machine learning algorithms (Linear Regression and Random Forest), with Model 1 performing the best; spatiotemporal variables from gait analysis were crucial in identifying PD severity. We aim to identify important features correlated with MDS-UPDRS and expect to be applied in clinical settings to monitor the severity of PD
ACUTE EFFECTS OF FOOTWEAR AND FOOTSTRIKE PATTERN ON ACHILLES TENDON LOADING DURING RUNNING
Get PDFThe study aimed to investigate the effect of footwear and foot strikes on Achilles tendon (AT) loading during running. Eleven male recreational runners with rearfoot strike pattern were recruited. The ground reaction force, kinematics, and kinetics of the ankle joint at 10 km/h were collected using an instrumented split-belt treadmill and a motion capture system. The morphological and mechanical characteristics of AT were recorded and calculated with a synchronous ultrasonic imaging instrument. The results showed a significantly greater peak AT force in minimalist shoes and forefoot strike pattern. The peak force and length change of the AT significantly increased when forefoot striking. It suggested that immediate use of minimalist shoes and/or transitioning to forefoot strike could provide higher tendon loading intensity to improve the loading characteristics of the AT
EFFECT OF ENHANCED ABDUCTOR HALLUCIS CONTRACTION ON FOOT BIOMECHANICS IN GAIT
Get PDFThis study aimed to investigate the effect of enhancing abductor hallucis (AbH) contraction by electrical stimulation (es) on foot biomechanics in gait. Ten healthy adults were recruited for this study. Ground reaction forces (GRFs) and navicular tuberosity (NAV) movement were recorded with and without AbH es during walking. The results showed that enhancing the AbH contraction reduced the range of motion of the NAV height (p=0.030). Meanwhile, the medial GRF was higher in the final stance and the center of pressure (COP) was laterally shifted in the whole stance phase. In conclusion, enhancing AbH contraction could stiffen the foot arch in gait and aid the body shift to the contralateral side in the final stance which may have the potential to inspire the intervention for individuals with arch collapse
REPORTING THE LOADING AND MOVEMENT PROFILES OF CHASSE-STEP AND ONE-STEP FOOTWORK IN TABLE TENNIS
Get PDFThis study aimed to analyze the biomechanical characteristics of athletes with two typical table tennis footwork. Eighteen elite athletes performed chasse-step and one-step. Kinematic and kinetic data were collected using the Vicon and AMTI. Hip joint flexion during one-step increased significantly in the backward swing (p=0.045) while knee joint extension with chasse-step increased greatly (p\u3c0.001) in the forwarding swing. The hip joint contact force of one-step increased in the ant-post direction (p\u3c0.001), though the chasse step contact force of the hip joint increased in the med-lat direction (p\u3c0.001). The findings suggested that the chasse-step had greater quality performance and preparation for the next successive stroke while the one-step showed faster performance which tended to direct score. This information may help coaches develop training programs, athletes improve performance, and prevent injuries
WORK SMARTER NOT HARDER: MECHANICAL WORK AS A MEASURE OF ATHLETE WORKLOAD
Get PDFA thorough understanding of competition workloads is necessary to optimize athlete readiness. The purpose of this study was to investigate the contribution of mechanical work within a measure of workload (session-RPE) in women’s rugby sevens. Data from 22 international athletes, participating in 103 matches were gathered, with a total of 1108 complete datasets available for analysis. GPS-monitors worn by athletes gathered data on time and speed. Overall absolute game mechanical work and session-RPE (sRPE) values were calculated. A linear mixed model evaluated the contribution of overall game work to sRPE by athlete. A strong significant association was found between sRPE and overall game work (R2conditional=69.3,
THE FOOT STRIKE ANGLE PREDICTS THREE-DIMENSIONAL KNEE JOINT MOMENTS IN PREPLANNED AND UNPLANNED SIDESTEP CUTS
Get PDFThis study investigated if knee joint moments are related to the foot strike angle in preplanned and unplanned handball-specific sidestep cuts performed by n = 51 female handball players. Canonical correlation analysis (CCA) with the foot strike angle as predictor variable was performed on the knee joint moment vector field (Mxyz). Subsequently, post-hoc tests using CCA for moment couples and linear regression for individual moment components were performed. In both conditions, the foot strike angle was related to Mxyz. However, the relationship remains partially unexplained when the three-dimensionality of the moment vector remains unaccounted for, especially in the unplanned cut. Given the time periods in which correlations exist, the foot strike angle shows potential to reduce multi-plane knee loading associated with ACL injury
AN EMG PREPROCESSING PIPELINE AND A GUI FOR PARALYMPIC CROSS-COUNTRY SKIING SITTING POSITION ASSESSMENT
Get PDFAn efficient sitting position and the sledge design are crucial for the success of para-athletes in cross-country sit skiing. However, there is a lack of studies on the effects of sitting positions on the performance of para-athletes. This study introduces an EMG preprocessing pipeline and a GUI to analyse and compare muscle activation in different sitting positions, as well as identify key factors to quantify the optimal sitting position. As desired by the coaches, this provides the opportunity to compare muscle activation during different sitting positions and conditions immediately after measurements. Test measurements were conducted with non-disabled athletes to validate the functionality of the EMG preprocessing pipeline and the developed GUI. This could allow coaches to quickly gain insights into the specific requirements of each athlete and make informed decisions on how the sitting position should be adjusted to improve performance and prevent injuries
THE EFFECTS OF RESTRICTING THORAX MOTION DURING FIXED-SEAT ERGOMETER ROWING
Get PDFThis study assessed the biomechanical effects of restricted thorax motion during fixed-seat ergometer rowing. Eleven able-bodied participants performed 2 bouts of 4 minutes of submaximal rowing on a custom-made fixed seat. First, the participants were strapped at the waist, allowing thorax motion (“Free thorax”), then strapped around the chest, preventing thorax motion (“Fixed thorax”). Kinematic analysis and force exerted on the ergometer chain were recorded. The “Fixed thorax” setup had lower total power output (p=0.011, Cohen’s d=1.61), total average joint power (p=0.006, Cohen’s D d=1.32) and VO2 (p=0.005, Cohen’s d=2.00). No differences existed in the elbow and shoulder power between the setups. The results suggest that restricting the thorax has a negative effect on submaximal effort rowing performance, which could have implications for competitions
CHARACTERISTICS OF HAMSTRING ELECTROMYOGRAPHIC ACTIVITY AND BREAK-POINT ANGLE DURING NORDIC HAMSTRING EXERCISE AT DIFFERENT ANKLE POSITIONS
Get PDFTo compare the electromyographic (EMG) activity of the biceps femoris long head (BFlh), and semitendinosus (ST) muscles during the Nordic Hamstring Exercise (NHex) while setting the ankle joint positions at plantar flexion, dorsiflexion (neutral), and dorsiflexed (neutral) position with support. Male volunteers randomly performed the following exercise: NHex with ankle dorsiflexion (DF), NHex with ankle dorsiflexion with sole support (DFS), and NHex with ankle plantarflexion (PF). The BFlh and ST EMG activities were measured. A repeated measures ANOVA was performed to compare the EMG activity during NHex with the ankle variations. The results showed that EMG activity was significantly higher during PF (p \u3c 0.05) compared to DF and DFS for the BFlh in the dominant leg. This study revealed that NHex activated higher BFlh activity in PF than in DF and DFS
AMATEUR BOXING COACHES PERCEPTIONS OF THE TECHNICAL COMPONENTS OF STRAIGHT PUNCHES
Get PDFBoxing coaches’ experiential knowledge from a variety of environments can be used to affirm quantitative findings and shed light on areas for future investigation. Five interviews were conducted with expert amateur boxing coaches on straight punch technique in amateur boxing. Reflexive thematic analysis derived higher order themes regarding the contributing body segments to straight punches, including the lower body, core and upper body. Coaches described punches as starting from the ground and transitioning toward the upper body ending upon impact via the fist. Coaches identified that important components of straight punches include stepping in, rotating the rear foot, rotating the hips and pronating the hand as well as bringing the shoulder up to protect the chin. They also stated that straight punch technique may change when used in combinations compared to single punches. This research highlights the important technical components of straight punches, this can help to inform boxing coaches, strength and conditioning staff and boxers of straight punching technique. Movements identified in this study can be observed in future kinetic and kinematic analysis of punching technique to better understand and interpret findings