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What if We\u27re on the Wrong Side? : Police Brutality, Protest, and Player Culpability in Heavy Rain and Detroit: Become Human
Get PDFChoice-based video games have often been called “interactive movies” for their unique position as a genre that lets players craft a unique story by making decisions that alter the game’s narrative. Two well-known examples in this genre, Quantic Dream’s Heavy Rain and Detroit: Become Human, offer a variety of possible story lines and outcomes for players to experience. However, because these two narratives are steeped in themes of police brutality, systemic racism, and protest, the way a player shapes a story does not exist in a relatively “moral-free” vacuum. Rather, the legal and social precedents that are often used to absolve police misconduct of blame by indicating an absence of choice are accentuated in these two video games. Through the lens of ludonarratology, which emphasizes both the played experience and the narrative of a video game, I will explain how both Heavy Rain and Detroit: Become Human demonstrate both the presence of personal choice and the institutional frameworks which inhibit agency in order to maintain power. In addition, the racial tones of Detroit: Become Human offer at times subversive readings of police brutality while maintaining dominant narratives of protest that protect white comfort
PILOT STUDY: OPTICAL TRACKING OF BARBELL KINEMATICS FOR LOW-COST STRENGTH TRAINING PERFORMANCE MONITORING
Get PDFVelocity based training (VBT) is a promising method to quantify and direct resistance training. Recent advances in computer science have opened the way for low-cost methods to measure VBT using video data from a smartphone. This work introduces and analyses the feasibility of a computer vision-based Python application in tracking barbell kinematics during VBT, compared against Vicon data during the back squat in one subject. As input into the algorithm, sagittal-plane video data is needed with the barbell plate in focus. Time of the concentric part of the squat and vertical barbell displacement are then automatically tracked using OpenCV libraries. The time parameter was accurately assessed using two different OpenCv Tracker, the KCF (r=0.83, SEE=0.02s) and the MOSSE (r=0.81, SEE=0.02s) tracker, respectively. For the vertical displacement, a lower accuracy was obtained using KCF (r=0.36, SEE=0.02m) and MOSSE (r=0.62, SEE=0.01m). Tracking errors could be explained by the camera set-up, as well as differences in frame rates between the video and the Vicon data. It might be possible to correct these errors in future work using machine learning techniques. This pilot study shows the feasibility of a computer vision-based Python application to measure barbell kinematics in a low-cost manner and might play a part towards advancing VBT monitoring technologies for widespread use
CONCURRENT ASSESSMENT OF SYMMETRY, VARIABILITY, AND COMPLEXITY OF STRIDE DURING PROLONGED OUTDOOR RUNNING
Get PDFThe aim of this study was to analyse the influence of acute fatigue on the asymmetry, variability, and complexity of the running pattern. We equipped 11 half-marathon participants with an inertial measurement unit (IMU) on each foot and a global navigation satellite system (GNSS)-IMU sensor on chest. Every 10 minutes of the race, the participant pronounced their perceived rating-of-fatigue (ROF) on a scale of 1 to 10. We divided the race into 8 equal segments, with one ROF score per segment, and included only the flat running parts. Temporal gait parameters were extracted using validated algorithms, followed by the computation of their asymmetry, and the variability and complexity of the cycle time (CT). Gait asymmetry increased significantly toward the end of the race and at higher perceived fatigue; faster runners showed a greater increase in asymmetry. CT variability increased significantly at the beginning of the race and then remained stable for all participants, but faster runners showed up to 20% less variability. No significant change was observed in CT complexity. This study highlights the increase in asymmetry and variability due to acute fatigue, with differences between fast/slow runners, and the importance of simultaneously measuring perceived fatigue and gait parameters under real-world conditions
BENEFITS OF DRAFTING ON THE LEADING CYCLIST: A PRELIMINARY FIELD STUDY
Get PDFThe effect of drafting on the aerodynamic drag of a trailing cyclist has been widely investigated. However, no experimental field study has quantified under field conditions the potential benefit of this strategy on the leading cyclist, which is the purpose of the present study. Therefore, a protocol based in a previous study performed in velodrome (García-López et al., 2014) was designed. Results indicate that drafting decrease the leading cyclist’s drag area (CdA) by 2.6 and 3.3%, and the trailing cyclist’ CdA by 31.9 and 19.3%, depending on the trailing cyclist position on the bicycle (i.e., aero vs. upright position, respectively). Although Rate of Perceived Exertion (RPE) values behaved similarly to CdA (i.e., when CdA decreased RPE also decreased), RPE method was not sensitive enough to detect small changes in aerodynamic drag
CHANGES IN UPPER LIMB JOINT POWER DURING ROUND-OFF IN FEMALE GYMNASTICS
Get PDFThe aim of the current study was to investigate joint power changes in upper limb joints during the support phase of three round-off (RO) techniques (reverse, parallel, T-shape). Twenty young female gymnasts performed 18 RO trials in three different techniques. Kinematic and kinetic data were collected for each trial. Statistical parametric mapping of mean joint power was performed to compare differences between techniques. Results demonstrated that the reverse technique had lower joint powers during the absorption and propulsion phases of the skill compared to the other techniques. The T-shape technique elicited greater wrist absorption, and elbow power generation. Wrist and elbow joint power absorption-propulsion peaks follow a distal-proximal pattern which reversed to a proximal-distal sequence of movement coordination across all techniques
ASSESSING KINEMATICS AND KINETICS OF HIGH-SPEED RUNNING USING INERTIAL MOTION CAPTURE: A PRELIMINARY ANALYSIS
Get PDFThe purpose of this study was to determine whether inertial motion capture (IMC) in combination with musculoskeletal modeling is a suitable method to assess lower limb kinematics and kinetics during high-speed running. Optical motion capture (OMC), IMC and ground reaction forces (GRF) were used as input for musculoskeletal models. Kinematics showed excellent correlations (knee: ρ=0.98, rRMSE=21.0%, hip: ρ=0.95, rRMSE=18.5 %, ankle: ρ=0.93, rRMSE=46.6%). The ground reaction force predictions showed varying results (anteroposterior: ρ=0.77, rRMSE=33.4%, mediolateral: ρ=0.04, rRMSE=69.1%, vertical: ρ=0.78, rRMSE=25.7%). The examined IMC and musculoskeletal modeling approach was proven a useful alternative to OMC and force plates for outdoor measurements in high-speed running
EFFECT OF TWO KINESIO TAPE TECHNIQUES ON KNEE KINEMATICS DURING A DROP JUMP TEST
Get PDFThis study investigated the effects of Kinesio® Tape on knee kinematics during a drop jump (DJ) test in 20 young women that had or were currently participating in competitive basketball or volleyball. Three taping conditions were randomly applied to the dominant leg of each participant: no tape (NT), gluteus medius (GM) facilitation, and spiral technique (ST). Multiple 3 x 2 RMANOVAs assessed the differences in peak knee flexion and abduction, and time to peak (TTP) angles, between taping conditions. No significant differences were found for peak knee angles or TTP, suggesting that GM and ST Kinesio® Tape applications did not alter measured knee kinematics during a DJ test. Any mitigation strategy should not depend on Kinesio® Tape alone and take a comprehensive approach that includes strength and neuromuscular training
HIGH LEVELS OF ENDURANCE TRAINING MITIGATE AGE-RELATED CHANGES IN RUNNING BIOMECHANICS – A LONGITUDINAL STUDY
Get PDFVery few studies to date examined lower body and joint stiffness in ageing endurance runners, the majority cross-sectionally. The present study longitudinally examined age-related changes in leg and joint stiffness regulation in consistently trained master endurance runners, as well as the contribution of individual joints in resisting collapse and generating propulsion. Highly trained master endurance runners (N=10) were studied over a period of seven years whilst maintaining their training regime. Data was collected at mean age 53.54 ± 2.56 and 60.49 ± 2.56 following an identical overground running protocol, using a Kistler force plate and a 12-camera Vicon motion capture system. Following seven years of ageing, leg stiffness was unchanged. The athletes maintained similar magnitudes of joint stiffness and moment at the ankle and the hip whilst knee joint stiffness at amortisation increased by 0.60o-1 (
THE ANALYSIS OF FORWARD ACCELERATION ASYMMETRIES DURING ON-WATER SPRINT KAYAKING
Get PDFThe study’s aims were to (1) determine normative values of the critical features of forward acceleration asymmetries in sprint kayaking, and (2) to investigate the effect of stroke rate (SR) on these asymmetries. Fifteen national-to-world class level sprint kayak athletes completed four, 30-second on-water trials at four different SR’s (60, 80, 100, and maximum strokes per minute). Critical features (i.e., maximum, minimum and range) from forward acceleration waveforms were extracted from ten single stroke cycles (i.e., five left and five right) for each trial. An asymmetry index (ASI) was used to determine the amount of asymmetry between left and right strokes for each critical feature. ASI’s of at least 8.0±11.7% up to 19.3±12.4% existed for all critical features combined. A one‑way repeated measures ANOVA with linear trend analyses showed all critical feature ASI’s increased with SR. These results provide appropriate asymmetry benchmarks for coaches to assess technical efficiency during on‑water sprint kayaking and exude the importance of analyzing left and right single strokes separately
INVESTIGATION OF A THEORETICAL MODEL FOR THE ROTATIONAL SHOT PUT TECHNIQUE
Get PDFThis study aimed to investigate the causal relationships among biomechanical variables for achieving high release velocity in male shot putter and create a theoretical model for the rotational shot put technique. The throwing motions of 22 male shot putters were videotaped and analysed using the 3D DLT method. Path analysis was used to examine causal relationships among biomechanical variables. The examined model consisted of three kinetic and eight kinematic variables that significantly related to a higher release velocity directly or indirectly. Two key factors were identified in shot put performance with the rotational technique: (1) increasing of impulse of the shot at delivery phase, and (2) creating greater linear and angular momentum before delivery. Future research should confirm or extend this potential causal mechanism of contributors to shot release velocity