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BALL SPEED PREDICTORS IN SLIDE ATTACKS IN FEMALE VOLLEYBALL PLAYERS
Get PDFThe purpose of this study was to investigate ball speed predictors of slide attacks and provide direct parameters for their proper execution. Healthy collegiate female volleyball players (n = 8) were recruited. After a warm-up, 3 successful slide attacks per participant and their ball speed were recorded using an 8-camera motion capture system and a radar gun. COM approach speed, maximum angular velocity of pelvis and torso rotation in the arm cocking phase, and maximum angular velocity of torso rotation, shoulder IR, and elbow extension in the arm acceleration phase were calculated for the trial with the fastest ball speed. The multiple stepwise regression was not statistically significant (p = .098). The findings indicate that peak torso rotation angular velocity in the arm cocking phase and peak shoulder IR and peak elbow extension angular velocities in the arm acceleration phase may be important contributors to the ball speed in slides
VARIABILITY OF BALL RELEASE PROPERTIES AND PITCH LENGTH ACCURACY IN CRICKET FAST BOWLING
Get PDFAccurate ball pitch length in cricket fast bowling is potentially achieved from a redundant combination of four ball release parameters. Yet, it is unknown how parameter co-variations affect pitch accuracy. This study investigates whether pitch length variance is determined by coordinated ball release parameter co-variability. Twelve fast bowlers performed 18 trials at a target length and ball kinematics were captured from an indoor 3D camera setup. Multi-linear regression analysis showed that the four release parameters accounted for 79% of pitch length variance, where vertical velocity variance accounted for the most variance. When each release parameter was independently shuffled across trials, a pitch length model showed no indication of coordinated co-variability between input parameters. Therefore, pitch length accuracy was achieved by independent control of vertical velocity
EVALUATION OF ACL AND MCL STRAIN UNDER NON-CONTACT LOADING OF LOWER EXTREMITIES USING A HYBRID CADAVERIC SYSTEM
Get PDFThe purpose of this study was to determine the strain in the ACL and MCL under simulated athletic activities using a novel hybrid robotic/cadaveric simulator. Four cadaveric knees, with ACL and MCL instrumented with strain transducers, were tested under simulated jump landing conditions from a height of 30 cm with various degrees of valgus orientation (fixed hamstring and quadricep forces) and various Quadriceps (Q) and Hamstring (H) force levels (fixed degrees of valgus). The response of Anterior Cruciate Ligament (ACL) and Medial Collateral Ligament (MCL) were monitored and assessed during the dynamic loading conditions. 4 – 5 tests were completed for each cadaveric leg, totalling 48 – 64 total tests. Analysis of data revealed that muscle activation (Q&H), in anticipation of landing, reduces the ACL strain even under severe valgus orientations. However, MCL strain is not influenced heavily by muscle activation
THE CONTRIBUTION OF HIP STRENGTH TO HIP ADDUCTION DURING RUNNING IS INFLUENCED BY STEP RATE, ANKLE DORSIFLEXION AND INJURY STATUS
Get PDFPeak hip adduction angle is frequently associated with running related injuries. The purpose of this study was to identify how clinical assessment measures interact to determine the presence of high or low peak hip adduction angles during running. A mixed sex sample of runners (n=125) comprising both injured and healthy controls were assessed for hip abduction strength and range of movement of the hip and ankle. Each runner then ran on a treadmill whilst 3D kinematic data was recorded, with peak hip adduction angles isolated from the data. All interest variables were analysed using a classification and regression tree procedure. This produced a model which was able to classify runners with either high or low peak hip adduction angles with an accuracy of 83.2%. The contribution of hip abductor strength to peak hip adduction angles was influenced by step rate, ankle dorsiflexion range of movement and injury status. This adds to our understanding of the relationship between hip strength and peak hip adduction
IMPLEMENTING FACULTY DEVELOPMENT MODULES TO INCREASE READINESS FOR ADDRESSING SOCIAL DETERMINANTS OF HEALTH, IMPLICIT BIAS AND EQUITY IN COURSE CONTENT
Get PDFImplicit bias is viewed as an unconscious and involuntary attitude that lies below the surface of consciousness but can influence behavior, and cognitive processes (Maina et al., 2018). Social determinants of health are considered to be the conditions in which people are born, grow, live, work, and age; these circumstances are usually shaped by the distribution of money, power, and resources at global, national, and local levels, which in turns determines the distribution of the value of medical care. Existing literature on implicit bias has been fragmented in different fields such as; cognitive psychology, business ethics, and higher education, but underexplored in health professions education (Joseph et al., 2018). Despite increasing attention to implicit bias recognition and management in health professions education, many programs struggle to meaningfully integrate these topics into curricula (Sukhera & Watling, 2018). The aim of this project is multifaceted. First; define social determinants of health and implicit bias and its impact on preparing teaching materials, allowing participants the ability to teach and demonstrate equitable and inclusive care to diverse populations. Secondly, to improve awareness among participants about the value of using preferred language and content when discussing social determinants of health. Lastly; provide participants with tools to identify and address implicit bias in content so participants can increase readiness for addressing social determinants of health when working with colleagues, students, and patients
ESTIMATING GIRAFFE (GIRAFFA CAMELOPARDALIS) POPULATION SIZE AND SURVIVAL RATES IN SOUTH LUANGWA VALLEY, ZAMBIA
Get PDFGiraffe populations across their range have declined significantly over the past 40 years. Recent studies of these declines noted that conservation efforts often lack basic population estimates and descriptions of demographic parameters such as sex- and age-specific survival rates. I addressed those research needs for a geographically-isolated population of giraffes (Giraffa camelopardalis) in South Luangwa Valley, Zambia. During 2016 to 2018, collaborators opportunistically photographed giraffes throughout South Luangwa National Park and adjacent Lupande and Lumimba Game Management Areas. Given that each giraffe has a unique spotting pattern, I created a photo inventory of the population and developed an extensive giraffe encounter database. I used this database with associated geographic and demographic data to: 1) develop a mark-recapture based population estimate in each of the three sampled years [mean = 555] for the Luangwa Valley giraffe population, and 2) estimate annual sex- and age- specific survival rates. Photographs will continue to be submitted in subsequent years, so the database developed for this study will form a substantial base for future demographic and ecological studies. The demography results gathered for this giraffe population will be used to inform status updates to the International Union of Conservation of Nature Red List and assist Zambian wildlife management agencies in decisions that affect the South Luangwa Valley giraffe population
Causes, processes, and effects of academic reorganization at public master’s universities in the United States
Get PDFThere is a wide-spread perception that universities reorganise their academic units frequently, although there is little beyond anecdote to support this. Similarly, the literature contains some speculation about what affects the success of such efforts, but there is almost no data to support various views. This study assesses the perceptions of academic reorganisations using survey responses from mid-level university administrators, deans and department heads. Relying on a random sample of administrators from Carnegie master’s institutions, we examine their perceptions of reorganisation success, as well as the processes and factors that influence reorganisation. Ultimately, we model dependent variables such as overall satisfaction with the process and perceptions of its benefits of reorganisation in order to explore associations between the nature of the reorganisation, the presence of planning, the role of institutional politics, and individual and institutional level control variables and these variables
ELITE FEMALE CRICKET POWER-HITTING BATTING TECHNIQUE DIFFERS BETWEEN FAST AND SPIN BOWLING DELIVERIES
Get PDFThe purpose of this study was to determine if elite female cricket batters’ body or bat kinematics differed when facing fast or spin bowling in a power-hitting task. Six elite female cricket batters completed a straight drive power hitting task against both fast and spin bowling, captured by a 3D motion capture system. Select kinematic variables were analysed using Visual 3D software. Elite female batters may use the increased movement time afforded by the slower spin bowling speed to enhance bat-ball impact, bat speed and launch angle through reducing distance from the pitch of the ball to impact, and increasing thorax-pelvis separation (X-Factor) and top wrist ulnar deviation compared with facing fast bowling
EVALUATION OF A TIME-FREQUENCY LOW-PASS FILTER METHOD FOR ASSESSING KNEE JOINT MOMENTS AND ACL INJURY RISK
Get PDFTime-frequency low-pass filters may enable more precise assessment of knee joint kinetics and help identify athletes at risk of ACL injury. The aim of this study was thus to evaluate use of a fractional Fourier filter (FrFF) for estimating knee joint moments during unanticipated sidestepping. 3D kinematic and GRF data were collected from 11 team sports athletes performing 45° cutting manoeuvres and knee moments were derived in five different low-pass filter conditions. The FrFF produced peak abduction moments similar to ‘unmatched’ Butterworth low-pass filter conditions (0.7 – 1.2 Nm/Kg) and larger than the ‘matched’ conditions (0.1 – 0.5 Nm/Kg). This preliminary evidence suggests time-frequency filters can help researchers identify athletes at risk from sustaining ACL injury
AGREEMENT AMONG COUNTERMOVEMENT JUMP FORCE-TIME VARIABLES OBTAINED FROM A WIRELESS DUAL FORCE PLATE SYSTEM AND AN INDUSTRY GOLD STANDARD SYSTEM
Get PDFThe purpose of this study was to explore the agreement between a wireless and portable dual force plate system, and an in-ground force plate system, which is an industry gold standard. The countermovement jump (CMJ) was compared across the two systems because it is the most popular force plate test in sports settings. Recreationally active adults (n=20) performed three maximal-effort CMJs on the portable force plates which were placed atop two adjacent in-ground force plates to enable simultaneous collection of raw force-time data (1000 Hz) over five seconds. Popular CMJ force-time variables were analysed for each system using a custom Microsoft Excel spreadsheet using criterion methods. Ordinary least products regression (OLPR) showed no fixed or proportional bias between the force plate systems for all variables. Thus, the portable force plate system may be considered a valid alternative to an industry gold standard for the assessment of CMJ force-time variables