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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.

The technical assessment of individual performance in rugby union players

Green, Andrew Craig January 2016 (has links)
A thesis submitted to the Faculty of Health Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree Doctor of Philosophy. Johannesburg, 2016 / Performance in Rugby Union relies on a wide variety of contributions of different individual skills. Individual tasks, such as passing, kicking or scrummaging are dependent on an individual’s ability and may vary according to a player’s playing position. The focus of this thesis is a series of studies which have assessed the performance of individual rugby players (particularly related to the assessment of passing, kicking and scrummaging) and to evaluate such performance in relation to factors (most often kinematic factors) which have been identified and correlated to better performance. The main body of this thesis includes seven studies, in the form of original papers, which firstly describe the factors which contribute to rugby passing accuracy (two studies), thereafter two studies which focus on kicking success are described. The final three studies describe the development of a new device for measuring individual scrummaging performance. These studies also investigated: the role of body positioning in the generation of scrummaging force; and assessed how such factors may respond to the fatigue experienced over the duration of a rugby game. One skill that all rugby players require is the ability to effectively pass the ball to another player. Two original research studies are presented in this thesis that describe multiple approaches to accomplishing passes in rugby players. A target frame was constructed, and the ball position relative to the centre of the target frame was recorded and reported as the accuracy error distance. The first study of this thesis assessed the accuracy of the running pass using self-selected passing strategies. Two strategies were identified: in-step passing and out-of-step passing, although differences in the step sequence resulted in no change in the pass accuracy. The second study evaluated the differences in accuracy and kinematic strategies used to execute the ground pass. Passes performed using a side-on body orientation were more accurate than those performed using a front-on body orientation. The two body orientations utilised different kinematic strategies: front-on relied on torso and pelvic rotations, whereas the side-on relied less on trunk rotations and utilised greater extension angles of the stance arm. Match victory can also be determined by individual kicking success, but in this case is reliant on the role of individual kickers in a team. In the third study, kinematic predictors of place kicking accuracy and distance were explored. Larger axial torso and pelvic rotations were related to further place kicks, and greater extensions of the stance arm was related to more accurate place kicks. However larger torso rotations, which were positively related to kicking distance, were negatively related to kick accuracy. The fourth study was devised to compare the kinematic sequences of two points scoring kicking types. The comparisons suggest that the body kinematics used during the place and drop kicks were not different, although kicking distances were further in the place kick. The fifth study of this thesis evaluated the feasibility of a custom individual scrummaging ergometer. The design, calibration, and measurement accuracy of the individual scrum ergometer are presented. Application of the ergometer revealed differences in individual scrummaging attributes, such as position of force application and centre of pressure variation, of players in different playing positions. No differences were observed in the force magnitude between playing positions. The sixth study investigated individual kinematic scrum performance using conventional kinematic techniques and the custom individual scrum ergometer. The results highlight the role of a lower body height and wider stance in the attainment of greater individual scrummaging forces. No static kinematic variables were related to individual scrum performance. The final study investigated the effects of fatigue resulting from a simulated rugby match on individual scrummaging kinetics and kinematics. Although an increase in psychological and physiological markers of fatigue were observed, no scrummaging v differences were noted in peak forces or in body kinematics at peak force following the rugby match simulation. In conclusion, the identification of performance related factors and the invalidation of others which have been identified in this body of work, may provide an opportunity for performance tailoring strategies of individual players, selection strategies for teams or even the tailoring of training practices to optimise performance. As an initial set of studies, however, many of these factors still need reassessment and validation by subsequent research and therefore this work has provided a number of research possibilities for later studies. To this end, a suggested topic of ensuing research may be to assess the repeatability of predictive power of the variables identified here, whether they are uniformly predictive over time or in different subject groups and lastly whether the individual performances (which were the focus of these studies) are translatable into team performance. / MT2017

The biomechanical and physiological predictors of golf drive performance, before and after a hole-to-hole distance walk

Green, Andrew 03 1900 (has links)
Dissertation submitted to the Faculty of Health Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree Master of Science in Medicine (Physiology). Johannesburg, 2012. / The game of golf requires players to strike a ball towards a distant target in as few as possible shots. One key component to the successful completion of this goal is a proficient golf swing. The golf swing is composed of a sequence of highly complex biomechanical movements requiring coordinated body movements and postural control. In addition, walking (a fundamental part of the game of golf) may have interesting effects on golf drive performance however, to date, this is largely unknown. The objective of the study was to identify the physiological and biomechanical variables that predict golf drive performance and to assess the effects of a hole-to-hole distance walk on golf drive performance. Twenty-one amateur golfers volunteered to take part in the study. The golfers were divided into two groups based on their recent average scores: More Competitive Group ((MCG) n=13, scores≤88) and Irregular Social Group ((ISG) n=8, scores>89). Drive distance (resting ball position) and accuracy (perpendicular distance from target) were directly measured. Balance and hand-eye coordination were assessed using a modified stork test and a customised three dimensional maze respectively. Lean mass was determined using bioimpedance. To determine walking effects participants hit ten golf balls and then walked 500m before repeating the tests. Average balance duration of both legs (r=0.45 p=0.048) the left leg (r=0.44 p=0.041) and the right leg (r=0.44 p=0.041) were all significantly correlated to drive distance. The hand and eye coordination task was correlated with total drive distance (r=-0.60 R2=0.36 p=0.008), but was not significantly associated with the centre of hit between the club face and ball. Significant contributors to a physiological model predictive of drive distance (R2=0.667; p=0.001) included age (β=1.228) lean mass percentage (β=1.899) and left leg balance (β=1.542). A corresponding biomechanical model (R2=0.9996; p=0.025; n=5) shows that leading arm angle (β=16.51), left elbow angle (β=-0.265) and lateral bend (β=-1.297) together significantly predict drive distance. Heart rate was significantly elevated following iv the walk for all golfers but was not significantly different between the groups before or after the walk. The MCG had significantly longer drives following the walk (p=0.018). The changes in drive distance were correlated to the changes in right leg balance with eyes closed (r=-0.62 R²=0.38 p=0.003). When considering changes in kinematic variables as a result of the walk, the change in the left knee angle at backswing (r=0.84 R²=0.71 p=0.017) and the right femur aspect angle at contact were correlated to the change in drive distance (r=0.87 R²=0.75 p=0.025). The physiological and biomechanical models described variables that predict golf drive performance, highlighting the importance of balance and the kinematics of the upper body segments during the swing. Furthermore this study identifies the beneficial effects of walking early in a round to golfers of better golf ability and the effects that such a hole-to-hole walk has on the physiological and biomechanical attributes of the golfer.

Les fédérations sportives : le droit administratif à l'épreuve de groupements privés /

Mollion, Grégory. Ribot, Catherine, January 1900 (has links)
Texte remanié de: Thèse de doctorat--Droit public--Grenoble, 2004. / Bibliogr. p. 375-396. Index.

Sport and the state : ideology and practice.

Willey, David Leonard. January 1988 (has links)
Thesis (Ph. D.)--Open University. BLDSC no. DX77536.

Collegiate athletes' perceptions of sport psychology a qualitative investigation /

Williams, Bradley Axson. January 2003 (has links)
Thesis (M.S.S.S.)--Miami University, Dept. of Physical Education, Health, and Sport Studies, 2003. / Title from first page of PDF document. Document formatted into pages; contains vii, 92 p. Includes bibliographical references (p. 84-88).

An insight into the acceptable use and assessment of lower-limb running prostheses in disability sport

Dyer, Bryce T. J. January 2013 (has links)
Sports technology can be any product or system used to facilitate, train or influence an athlete’s performance. The role of prostheses used for disability sport was initially to help facilitate exercise and then ultimately, competition. In able-bodied sport, controversy has occasionally been caused through the adoption or introduction of sports technology. However, scant attention has been paid to sport with a disability with respect to such concerns. This research project provides a novel contribution to knowledge by investigating the use of lower-limb running prostheses in competition by trans-tibial amputees. A novel study using a mixed method approach has investigated the nature, use and assessment of lower-limb running prostheses. It has proposed that the unchecked introduction of such technology has affected the sport negatively. From this, the study conducted a stakeholder assessment of the sport and provided a proposed series of guidelines for lower-limb prostheses technology inclusion. Finally, the recommendation was made that a proactive approach to such technologies’ inclusion in the future should be implemented. These guidelines were further developed by assessing symmetrical and nonsymmetrical lower-limb function and proposed that single and double lowerlimb amputees should be separated in competition in the future. To this end, it was proposed that lower-limb symmetry, stiffness and energy return were important means of monitoring prosthesis performance. Ultimately, a dynamic technique which assesses these qualities was proposed as an assessment strategy for further development in the future.

American sports (1785-1835)

Holliman, Jennie, January 1931 (has links)
Thesis (Ph. D.)--Columbia University, 1931.

Sport development in Kuwait perception of stakeholders on the significance and delivery of sport /

Aldousari, Badi, January 2004 (has links)
Thesis (Ph. D.)--Ohio State University, 2004. / Title from first page of PDF file. Document formatted into pages; contains xi, 133 p. : ill. Advisor: Packianathan Chelladurai, College of Education. Includes bibliographical references (p. 112-115).

Significance and delivery of sport in Belize perceptions of selected experts /

Cuellar, Clara R. January 2002 (has links)
Thesis (Ph. D.)--Ohio State University, 2002. / Title from first page of PDF file. Document formatted into pages; contains xii, 147 p. Includes abstract and vita. Advisor: Packianathan Chelladuria, Dept. of Education. Includes bibliographical references (p. 101-106).

Sport involvement as a function of social class and ethnic group background

Martindale, Colin A., January 1971 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1971. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

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