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JOINT DISPLACEMENTS AND PEAK ACHILLES TENDON FORCE DURING IRISH DANCING-SPECIFIC LANDING TASKS
Get PDFAchilles tendinopathy is prevalent among Irish dancers, thought to be due to the high impact, stiff-style landing tasks associated with the sport. This study aimed to investigate the relationship between sagittal plane joint displacements, at the ankle, knee, hip and thorax segment, and peak Achilles tendon force during an Irish dancing ‘leap over’ landing task. Kinetic and kinematic data were collected for 12 participants performing the ‘leap over’, and used to calculate peak Achilles tendon force and joint displacements. Results of the study found a statistically significant positive correlation between ankle dorsiflexion and peak Achilles tendon force during the ‘leap over’. These findings can be used to inform future research into the effect of joint displacement on peak Achilles tendon force, and to develop strategies to help dancers reduce their risk of developing Achilles tendinopathy
RELATIONSHIP BETWEEN HIP RANGE OF MOTION AND PITCHING KINEMATICS IN HIGH SCHOOL BASEBALL PITCHERS
Get PDFThe purpose of this study was to examine the association of hip rotational range of motion (ROM) with lower extremity and trunk kinematics in high school baseball pitchers. Twenty-five healthy high school baseball pitchers volunteered (15.9 ± 1.1 years). Passive hip internal rotation (IR) and external rotation (ER) ROM was measured with the pitchers seated using a digital inclinometer. Total hip ROM (IR + ER) was calculated for the stride leg and drive leg. Biomechanical data were collected with a 3-D electromagnetic tracking system while pitchers threw three fastballs. Simple linear regression analysis determined drive and stride leg hip IR, ER, and total ROM did not predict pitching kinematics. Future research should continue identifying parameters associated with altered biomechanics that may place baseball pitchers at increased risk of injury
KINEMATIC AND KINETIC ANALYSIS OF THE HORIZONTAL HANG CLEAN PERFORMED WITH A VARIETY OF LOADS AND THEIR COMPARISON TO THE SPRINT START
Get PDFThis study evaluated kinetic and kinematic aspects of the horizontal hang clean (H-HC) at a variety of loads and also compares these results to the standing sprint start (SSS). Subjects were tested during the H-HC at 30%, 50% and 70% of their five-repetition maximum (5RM), and during the SSS, using two force platforms. Analysis revealed significant differences for the H-HC conditions for the propulsive phase vertical GRF (p ≤ 0.001), propulsive phase horizontal to vertical GRF ratio (H:V) (p = 0.001), subject/barbell displacement (p ≤ 0.001), and velocity (p ≤ 0.001). The propulsive H:V of the H-HC at 30% of the 5 RM was correlated to the propulsive H:V of the first step of the SSS (p = 0.04, r = 0.55). To maximize subject anterior displacement and velocity and propulsive H:V, practitioners should use the H-HC with loads of 30% of the 5 RM. Training in this manner offers specificity for sprinting starts
LINEARITY OF THE RATIO OF FORCES-VELOCITY RELATIONSHIP IS NOT RELATED TO INITIAL ACCELERATION PERFORMANCE IN SPRINTING
Get PDFThe relationship between the linearity of the ratio of forces (RF)-horizontal velocity (vH) profile and initial acceleration (IA) performance was investigated in trained sprinters. Ground reaction force data from the IA phase of a maximal sprint from a block start were analysed. The coefficient of determination of the linear trendline fitted to four step-averaged values of RF and vH provided a measure of linearity. Semi-partial correlations (sr) accounting for block phase performance revealed a weak negative relationship between linearity of the RF-vH profile and performance over the first four steps (sr = -0.11), while mean RF displayed a very strong positive relationship with performance (sr = 0.80). Sprinters and coaches should therefore prioritise the production of a high RF during IA above trying to ensure a consistent decline in RF as velocity increases
DEFINING MOVEMENT STRATEGIES IN SOCCER INSTEP KICKING USING THE RELATIONSHIP BETWEEN PELVIS AND KICK LEG ROTATIONS
Get PDFThe aim of this study was to examine the relationship between pelvis and kick leg rotation strategies during soccer instep kicking. Twenty semi-professional players performed kicks for maximal speed and accuracy. A strong relationship was shown between pelvis transverse rotation (i.e. speed of rotation of kick side hip towards the ball upon impact) and kick leg (i.e. thigh-knee angular velocity ratio upon impact) strategies (r = 0.760,
BIOMECHANICAL ANALYSIS OF LOADED PLYOMETRIC EXERCISES
Get PDFPlyometric intensity and specificity are determined by the exercises performed. This study assessed ground reaction forces (GRF) in the frontal (F), horizontal-anterior (H), and vertical (V) planes, and the ratio of H to V GRF (H:V) of plyometric exercises and load conditions. Subjects (N=15) performed five plyometric variations with five handheld loads on two force platforms. A two-way RM ANOVA was used. Analysis of F GRF revealed main effects for plyometric exercise (p = 0.004). Analysis of H GRF revealed main effects for plyometric load (p = .042) and plyometric exercise (p ≤ 0.001). Analysis of V GRF revealed main effects for plyometric load (p ≤ 0.001) and plyometric exercise (p ≤ 0.001). Analysis of H:V revealed main effects for plyometric exercise (p ≤ 0.001). Practitioners should use the plyometric exercises and loads that optimize the kinetics and transfer of training
Evaluating Pika Colonization Through Parasite Histories
No full textPikas, small lagomorphs that live at high elevations across western North America and Central Asia, have a complex history of intercontinental exchange. Previous work on the tapeworms (genus Schizorchis) of pikas suggested that there were two separate waves of colonization into North America from Asia. One of these colonizations occurred during the Pliocene and another occurred during the Late Pleistocene. However, this earlier study did not include complete sampling of Schizorchis diversity. Depending on the phylogenetic placement of Schizorchis species that were not previously sampled, the timing of the earliest pika colonization of North America could be called into question, potentially suggesting that North American Schizorchis arrived in a single colonization event. To evaluate this possibility, I am adding new DNA sequence data - collected from Asia - that represents additional Schizorchis lineages. By doing so, we are reconstructing the evolutionary history of these lineages and providing a more complete picture of the history of pika colonization between Asia and North America
ENGAGING SECONDARY STUDENTS: THE BENEFICIAL INTERSECTION OF YOUNG ADULT AND CLASSIC LITERATURE
Get PDFThe positive attributes of both classic and young adult (YA) literature are significant, even when read separately. However, the benefits of pairing classic and YA literature together are even greater; yet, teachers often avoid integrating YA literature for a variety of reasons (Velazquez). Both administrators and the parents of students may question the use of YA literature, but that doesn’t mean educators should give up on using it as an instructional tool. Many of those in opposition to using YA literature would still agree that students struggle to find motivation to read classic literature. Students often have difficulty comprehending the classics in comparison to YA literature, which they read with ease. In Using Young Adult Literature to Increase Student Success and Using Young Adult Literature to Increase Student Success and Teach Multiculturalism Kirsten Toscano discusses classic literature, stating, “these texts are difficult for students to relate to and therefore engage in meaningful and purposeful reading of” (2). As a way to increase student motivation and comprehension of the classics, teachers should find a YA novel that has a similar theme or plot and teach them side by side, or one after the other. In turn, students’ motivation and comprehension of the YA novel will also improve when paired with a classic text (Velazquez). The two forms of literature will build up and strengthen one another, making pairing classic and YA literature an extremely effective educational method
Human As We All Are: Posthuman Subjectivity in The Paper Menagerie and The Three-Body Problem
No full textThe purpose of this thesis is to examine the formulation of posthuman subjectivity in contemporary science fiction through stories that collapse the distinction between humans and machines. I draw upon contemporary research on the sociological implications of such technologies as artificial intelligence, virtual reality, and brain-computer interfaces (BCI), to analyze the ways in which literature that depicts these technologies disrupt the humanist subject. I also consider the ways in which the disruption of the human subject serves to write against imperialist and techno-Orientalist discourses in science fiction and the study thereof. Chapter One compares the representations of technology and magic in the stories of Ken Liu’s The Paper Menagerie, particularly the way technology magnifies humanity through the effects of algorithmic bias. Throughout the collection, Liu’s stories communicate with one another through “questions” and “answers” about humanism. Chapter Two focuses on how representations of virtual reality and BCI in Cixin Liu’s The Three-Body Problem both extend, and reveal the ultimate shortcomings of, human subjectivity
Amor fati
No full textThe Abstract is meant, despite what its name suggests, to make a given work definite and knowable, to map its parameters in order that the reader, scholarly or otherwise, can determine the worth of a given work – relative to their needs or interests – without having the inconvenience of reading the work itself. In the world of literary publishing, a paragraph like this is meant to convey the most compelling – read: saleable – features of a text in order to entice consumers to purchase one book over another, to take a certain path within the networks of global capital, changing a few ones and zeroes in a sales database that – amalgamated with other, similar changes – might increase, ever so slightly, the satisfaction of an executive board whose goodwill might be passed-on, in reasonable measures, to their underlings who, at best, will get a small holiday bonus, but who, more likely, will just be glad to have another day where they can be fairly certain they will not be fired for having written jacket copy that displeased The Market. The work of fiction contained herein is different, because it knows that either you are the type of person who will read it or you are not – and which type of person you are has already been determined by so many other infinitesimal decisions like this one – binaries, ones and zeroes. There is no point in trying to convince you; you have always already decided – amor fati