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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.
201

Isokinetic muscular strength and performance in youth football : relationships with age, seasonal variation and injury

Forbes, Hollie Samantha January 2012 (has links)
The primary aim of the current project was to investigate the isokinetic muscular strength and performance of elite male youth footballers, and the relationships with age, seasonal variation and injury. A secondary aim was to use the information gathered to target muscle strain injury prevention strategies to particular age groups and times, and evaluate the effect. The primary aim was achieved by establishing normative patterns for muscular strength and performance of elite male youth footballers (grouped according to chronological and biological age) across a competitive season of youth football in Chapters Four and Five. Isokinetic muscular strength (characterised by peak torque (PT) and peak torque relative to body weight (PTBW)) of the hamstrings (H) and quadriceps (Q) using both concentric (CQ, CH) and eccentric muscle actions (EH) was evaluated. Muscular performance of the same muscle groups (characterised by H:Q ratios (conventional (CHQ) functional (FHQ)), asymmetry (dominant (dom):non dominant (ndom) leg ratios (e.g. CQ:CQ)), and angle of peak torque (AoPT)) was also investigated which necessitated an isokinetic speed of 60 °/s. Isokinetic evaluation was completed three times over the course of a regular playing season (start of season (SS) mid season (MS) and end of season (ES)). Participants were grouped according to chronological age (n=152, under 12 (U12) - under 18 (U18)) and biological maturation (according to Pubertal Development Scale (PDS 1 - 5) n=134). Forty seven participants completed SS, MS and ES isokinetic evaluation. Bilateral isokinetic evaluation consisted of five maximal repetitions of CQ and CH, followed by five repetitions of EH, leg dominance was counter-balanced. Repetitions two-four were used to calculate PT, PTBW, dom:ndom and AoPT for CQ, CH and EH, CHQ and FHQ; these measures were compared across chronological and biological age groups using a mixed model ANOVA. Dom:ndom CQ, CH and EH were compared across chronological and biological age groups using a one way ANOVA, while the relationship between AoPT and PT/PTBW was considered using a Pearson’s correlation. Additionally, the relationship between chronological and biological age, and PT/PTBW was investigated using a mixed model ANOVA within PDS group three. For analysis of seasonal variation a mixed model ANOVA was applied for all isokinetic measurements which considered time (SS, MS, ES), leg dominance (dom, ndom) and age group (U12 -U15) with a further mixed model ANOVA performed on CQ:CQ, CH:CH and EH:EH. Where appropriate SIDAK corrections were applied and the level of significance was accepted at p≤0.05. The main findings were that youth footballers did not increase their PT and PTBW EH in-line with CQ and CH as chronological and biological ageing progressed, this lead to a significant FHQ imbalance at U18. Dom:ndom CH comparisons identified that the chronologically younger and biologically less developed groups displayed a significantly stronger dom leg which may be explained through the concepts of skill acquisition and trainability. Biological age was not found to exert any additional effect over and above that of chronological ageing as significant differences in muscle strength still existed according to chronological age group within PDS group three. Additionally, AoPT EH and PT EH were found to be significantly negatively correlated on both legs which supported a potential mechanism for non contact hamstring muscle strain injury during running. Analysis of seasonal variation revealed that all PTBW measures showed a MS decrease. This may be related to breaks in normal training activity and links appropriately to times of peak injury incidence highlighted in youth football. In order to achieve the secondary aim of the current project Chapters Four, Five and Six investigated the relationship between isokinetic muscular strength and performance, muscle strain injury of the thigh, and injury risk attenuation. A retrospective and prospective injury audit was undertaken for the elite male youth football participants. For the retrospective approach participants were grouped according to chronological age (n=147) or biological age (n=128) and indicated using a self-report injury form their history (ever, (Hx)) or recent history (12 months, (Hx12)) of hamstring, quadriceps and adductor injuries. Approximately each player had an Hx of muscle strain injury and 0.56-0.59 of players had an Hx12. The hamstrings were the most commonly injured muscle group and the prevalence of muscle strain injury Hx and Hx12 increased with chronological and biological age. The prospective audit (n=50) identified that 0.16 of players sustained a muscle strain injury during the season, 0.08 of these being to the hamstrings. Between group comparisons (one way ANOVA with SIDAK correction) were also performed to investigate the difference in isokinetic measures between those participants who had an Hx12 of muscle strain injury and those who did not. It was discovered that for Hx12 of an injury to the dom hamstrings the injured group had less PTBW CH and EH on the dom leg. The injured group also had more inner range AoPT CH. These findings linked appropriately to the reported mechanisms and risk factors for hamstring injury but the exact direction of cause and effect could not be established. To this end a logistic regression analysis was undertaken in an attempt to predict which group (injured vs. non injured the 50 participants would belong to, using evidenced based risk factors in the experimental model. No predictive relationship between risk factors (including altered isokinetic muscular strength and performance) could be established. The information regarding the relationship between injury and muscular strength and performance may highlight a role for isokinetic screening to ensure adequate rehabilitation from injury. Injury risk attenuation strategies were investigated through an exercise intervention using the U18 age group following a break from football activity. The participants were split based on their FHQ at initial isokinetic evaluation (via odd and even placing) to form control (n=8) and intervention groups (n=8). Isokinetic evaluation was conducted as previously outlined and the exercise intervention targeted the hamstrings. Only six of the control group and seven of the intervention group completed the study and were compared using a mixed model ANOVA. Results showed that the intervention group were not significantly different to the control group post intervention for any of the isokinetic muscular strength and performance measures, though both groups significantly improved over time for the ndom leg CHQ and PTBW EH, and FHQ improved for both legs. Contamination of the control group may explain the lack of significant difference between groups. However, the exercise intervention was not targeted to individuals who displayed prior alterations to isokinetic muscular strength and performance, and this approach was discussed using the results of one member of the intervention group. In summary, the current project achieved the stated aims by discovering normative patterns of isokinetic muscular strength and performance according to age and seasonal variation. Injury risk attenuation strategies were targeted appropriately to the U18 age group following a break from football activity. However, the applied evidence based exercise may have been more effective if targeted to ‘risk’ after isokinetic screening.
202

A transtheoretical model intervention to help Greek students adopt and maintain a physically active lifestyle

Tzormpatzakis, Nikolaos January 2012 (has links)
Physical activity is positively related to a number of health benefits that influence morbidity and mortality during childhood, adolescence and adulthood. However, an epidemic of physical inactivity is quickly expanding worldwide and particularly affecting the Greek population. Early life periods and especially transitional ones leading to young adulthood are considered critical to intervene to help people adopt and maintain an active lifestyle. Well-designed longitudinal interventions are recommended for these ages. The main objective of this study was to design, implement and assess an intervention to help students adopt a more active profile according to the Transtheoretical model. This theory was selected due to its practicality and adaptability. The intervention materials consisted of a set of five printed manuals based upon the Transtheoretical model and encouraging physical activity. The study design was quasi-experimental (n=665, mean age=15.8 years, 57% girls) with a stratified assignment of the intervention (nInt=263) and control group (nCon=402). The intervention consisted of the administration of one printed manual to each student according to his/her current stage and its use for the next four months. Greek secondary students were measured longitudinally in the course of three years extending from two years before their graduation until one year after their graduation. The first two measurements were performed in the second grade of Lyceum (Greek high school) one just before and one just after the intervention. The last two measurements were conducted one year after and two years after the intervention. The research questionnaires measured stages of change, processes of change, decisional balance and self-efficacy, which are the main components of the Transtheoretical model. These instruments assisted firstly with the implementation and secondly with the assessment of the intervention. The research hypotheses examined the various intervention effects. The main analysis of the stage data was performed with latent transition analysis, which was considered as appropriate and advantageous. The latent stage results revealed positive intervention effects in the short-term, which were neutralised in the mid- and long-term. A comparison of the observed stage data pre- and post-intervention confirmed that in the short-term the intervention had successfully helped more students to progress and fewer students to regress along the stages of change continuum compared to the control group. Regarding self-efficacy, decisional balance and processes of change, within-group longitudinal comparisons of the observed data disclosed positive comparative short-term effects. In general, these effects were also reversed or neutralised in the midterm and remained neutral in the long-term. In most cases the above-mentioned trends of the whole sample were also confirmed for each gender separately making the intervention successful only in the short-term. Several shortcomings identified in the literature were addressed by the current study by implementing a longitudinal design, conducting a long-term investigation of the intervention effects and specifically adapting and validating the research instruments for the studied population. The “less is more” approach encapsulates the philosophy behind this intervention. In fact, the resources used were kept in a minimum regarding students’ time and schools’ involvement. Together with the easiness of the administration of the intervention contributed to the potential of being easily generalisable to wider populations. Additionally, the development and implementation of the Greek adolescent stages of change manuals was a pioneer work for Greece. It is recommended that a number of successive interventions be implemented to accomplish a longer duration of positive results. Another recommendation was to expand the public impact of this intervention by attempting it on a larger, even national scale and in different settings. Finally, the positive conclusions of the current study confirmed its success in helping young people adopt and maintain an active lifestyle and also it provided similar future studies with validated tools and added experience to continue in the search for more efficient PA interventions.
203

Training load monitoring in soccer : the dose-response relationships with fitness, recovery and fatigue

Akubat, Ibrahim January 2012 (has links)
The congested fixture schedules in elite soccer leagues around the world has bought the issue of recovery between games and subsequent performance to the fore in soccer related research. Studies have described the time-course of recovery for numerous biochemical and physiological measures of performance, fatigue and recovery from match-play. However, the research also suggests that there is individual variation in the external load both between players and between matches. The external load measured as distance in match-play has been shown to vary by ~30% between games. However it is the internal training load that will determine the magnitude of the physiological responses on an individual basis. Therefore the major aim of this thesis was to examine the dose-response relationships between measures of training load and the physiological and biochemical responses used as markers of recovery from match-play. The thesis also assessed the relationships between these proposed markers of recovery and soccer specific performance. In meeting the aims of the thesis a number of preliminary studies were conducted. The study in section 3 assesses the extent of fixture congestion in the English Premier League. The results showed over 30% of games for the most successful teams are played with 3 days recovery time, justifying the need for investigating recovery from soccer match-play. Given the variation in soccer match-play section 4 examines the reliability and validity of the modified BEAST90 soccer simulation. A measure of performance with less variance would allow changes in soccer specific performance to be identified with greater certainty in section 7. Section 5 assesses the influence of intermittent exercise on the blood lactate response. Given that the new iTRIMP method of measuring internal training load weights exertion with the blood lactate response it was important to assess the influence exercise mode may have on the calculation of internal training load. The results showed that at higher intensities intermittent exercise produced significantly higher blood lactate responses. Section 6 assesses the dose-response relationships between training and fitness using numerous measures of internal training load over a 6 week training period. The results showed only the iTRIMP method showed a significant relationship with changes in fitness. Section 7 assesses the dose-response relationships between exertion in soccer match-play and various physiological measures of fatigue and recovery. The relationships between these measures and changes in soccer specific performance were also assessed. Finally the internal and external load were integrated and the relationships of this ratio assessed with measures of fitness and performance. The results showed that changes in any of the physiological and biochemical measures used to assess recovery did not relate to changes in performance with the exception of testosterone which showed significant positive relationships with changes in distance covered from the 1st trial of the modified BEAST protocol to 2nd. Testosterone also was the only measure to show a significant relationship during the recovery period with any measure of training load (sRPE). Finally, the novel findings of this thesis is the relationships between the integrated ratio’s of internal and external training load with measures of aerobic fitness is also presented in section 7. The studies provided in this thesis have made a major contribution in demonstrating how data that is routinely collected at elite levels of soccer can be used more appropriately. It has also shown limitations of some the methods currently employed to measure training load. Furthermore changes in many of the markers used to assess recovery of soccer players do not seem to relate to changes in soccer specific performance. This may point to a change in paradigm which is required in both research and practice.
204

Exercise behaviour change among a sample of Malay students living in northern England : an application of the transtheoretical model

Omar Fauzee, Mohd Sofian Bin January 1999 (has links)
This programme of research was concerned with an examination of the exercise behaviour change of a sample of Malay students living in five different cities in Northern England (Bradford, Leeds, Manchester, Newcastle-upon-Tyne and Sheffield). The research methods used were a cross-sectional study (Study 1), an in-depth interview (Study 2) and a longitudinal study, divided into two parts - quantitative (Study 3A) and qualitative (Study 3B). These three studies were conducted in order to answer four main Research Questions: I. To what extent is Prochaska and DiClemente's (1983)Transtheoretical Model usefuli n examiningt he exerciseb ehaviouro f the students? A cross-sectional study (Study 1) was employed to answer the first research question. The respondents (N = 123) were drawn from two annual meetings of the Malaysian Students Societies at Leeds Metropolitan University and Leeds University. The results showed that there was a relationship between the stages of change and the processes of change, self-efficacy and decisional balance. On the basis of the findings of this initial study (Study 1), two new contributions to the field of exercise behaviour were made: a culture-specific exercise intervention programme was devised, and evidence was provided that the Transtheoretical Model is a wholly suitable vehicle for explaining the exercise behaviour of the students. 2. What factors influenced the exercise behaviour of the students? To answer the second research question, Study 2 (an in-depth interview) was employed, using 20 of the students from Study 1. Study 2 identified the factors that inhibit and those that enhance exercise participation. The nine inhibiting factors were: time constraints, attitude-related factors, lack of guidance, lack of exercise partner, lack of interest, poor weather, lack of child-care facilities, unhealthy physical condition and lack of experience. The five enhancing factors were: health and fitness, sociological factors, psychological benefits, good facilities and a history of exercise. The study also enabled the researcher to make three more contributions in the area of exercise behaviour. These were: the discovery of the "Proselytizing" stage, the fact that the Processes of Change Instrument fails to take into account "involuntary" factors and a proposal for revising the Stages of Change Instrument. 3. Is there any identifiable pattern of change in their exercise behaviour, over a period of time? Study 3A, which employeda longitudinals tudy,o ver an eight-monthp eriodw as able to provide an answer to the third research question. The respondents (N=110), Malay students newly-arrived in England, were contacted through the Malaysian Students' Societies in five different cities in Northern England (Bradford. Leeds. Manchester, Newcastle-upon-Tyne and Sheffield). There were three data collection during the eight-month period of investigation (baseline, follow-up and third data collections). The results revealed that the processes of change scores increased in the Adopters groups, decreased in the Relapsers group, and remained substantially the same in the Stable Inactive and Stable Active groups. Study 3A highlighted the limitations of the Processes of Change Instruments used in earlier studies and revealed that the Marcus et al., (1996c) method of identifying Adopters and Relapsers was inadequate. It also suggested that "Stable Preparers" group should be identified as an additional group, apart from Stable Active and Stable Inactives groups. 4. What are the factors that caused the newly-arrived Malay students to relapse from exercise the over four-month period? Thirty students who were found to have relapsed, in the follow-up data collection (Study 3A) were invited to participate in this study. Of the thirty students, nineteen agreed to participate in the qualitative, longitudinal study. Study 3B revealed that weather conditions, lack of time and lack of exercise partner were among the most prominent reasons why recently-arrived students relapsed from exercising. Furthermore, the study also demonstrated that cultural and religious differences contributed to their relapse from exercise. Recommendations for future research, in this area also, are advanced.
205

Why we're all going on a summer holiday : the role of the working-class organisations in the development of popular tourism, 1850-1950

Barton, Susan January 1999 (has links)
No description available.
206

Biomechanics and quality of life in transtibial amputees during and following rehabilitation : a longitudinal study

Barnett, Cleveland Thomas January 2011 (has links)
Following surgery, amputees must re-learn how to perform various movement tasks using altered lower limb mechanics. In order to optimise the process of re-learning these tasks and inform rehabilitation practice, an understanding of the longitudinal adaptations that occur both during and following a period of rehabilitation must be established. Scientific literature has reported the biomechanical, balance and quality of life (QOL) characteristics of transtibial amputees. However, no studies to date have outlined how these characteristics develop over time. The aim of this thesis, therefore, was to investigate the longitudinal changes that occurred in unilateral transtibial amputee movement, balance and QOL from their first treatments following amputation up to six months post-discharge from rehabilitation. Studies one and two assessed the kinematic and psychological adaptations that occurred during the rehabilitation of 15 unilateral transtibial amputees. The amputees were randomly allocated into two groups, differing by early walking aid (EWA) used. One group used the Amputee Mobility Aid (AMA), which incorporated an articulation at the knee joint. The other group used the Pneumatic Post-Amputation Mobility Aid (PPAM) with no articulation at the knee joint. Amputee�s gait and quality of life (QOL) were assessed at five standardised time points using three-dimensional motion capture and the SF-36 questionnaire, respectively. Overall, amputee�s gait improved with walking velocity increasing over time (p
207

The motives of endurance athletes to participate in cause-related or non-cause-related sport events

Rundio, Amy Susan 05 October 2011 (has links)
Many non-profit organizations in need of funding have turned to using endurance athletic events as fundraisers. These events, also known as cause-related sport events, can fulfill the many needs and desires of athletes. This study was designed to compare the motives of athletes in cause-related and non-cause-related sport events. Using the Motives of Marathoners Scales (MOMS), participants were asked to rate their motivations for attending either a cause-related sport event or non-cause-related sport event. Multiple motivations were found for attending both cause-related and non-cause-related sport events. Being associated with a cause provided cause-related sport events with an attribute that attracted participants for self-esteem, recognition/approval, personal goal achievement, and competition reasons. Non-cause-related events attracted participants motivated by general health motives. Overall, motives to attend events can be affected by the event’s attributes, such as affiliation with a cause, and these event attributes can fulfill more than one motive. / text
208

Documentation of the clothing styles of American women in tennis, golf, and swimming from 1870 to 1970

O'Brien, Jane Alice, 1949- January 1972 (has links)
No description available.
209

Coping with interpersonal sport stress in female adolescent soccer players: the role of perceived social support, cognitive appraisal, and trait social anxiety

Cayley, Clare 05 1900 (has links)
Stress in sport is complex and can lead to a number of undesirable consequences such as burnout, performance difficulties, interpersonal problems, and injury. Lazarus’s (1991, 1999) Cognitive-Motivational-Relational model holds that stress is best understood as a transactional relationship between a person and their environment. Stress is a process which is influenced by appraisals and coping. Appraisals are influenced by personal factors as well as environmental demands and the availability of external resources. Coping involves constantly changing cognitive and behavioral efforts to manage the perceived external and internal demands of a stressful situation (Lazarus & Folkman, 1984). The present study examined how appraisal processes mediated (or were possibly moderated by) the effects of social anxiety and perceptions of teammate social support on how high school female soccer players thought they would cope with a hypothetical interpersonal stressor. The study also examined simple relationships among variables. The participants were 181 female high school soccer players from Greater Vancouver. The athletes first completed two questionnaires designed to measure social anxiety (Interaction Anxiousness Scale; Leary, 1983a) and perceived social support from teammates (modified Social Provisions Scale; Weiss, 1974). After reading the scenario, the athletes indicated their appraisal of threat and challenge (Stress Appraisal Measure; Peacock & Wong, 1990) and how they thought they would cope (Coping Functions Questionnaire; Kowalski & Crocker, 2001). . The initial findings indicated that challenge appraisals were moderately correlated with both emotion-focused (r = .41) and problem-focused coping (r = .51), whereas threat had a weak association with avoidance coping (r = .19). Using mediation analysis, the results indicated that challenge fully mediated the relationship between social support and emotion-focused coping, and partially mediated the relationship between social support and problem-focused coping. Threat appraisals mediated the relationship between social anxiety and avoidance coping. Contrary to hypotheses, there was no evidence that social anxiety or threat were related to emotion-focused coping. There was also no support that person variables (social anxiety, social support) moderated the effects of appraisal on coping. The findings suggest that challenge appraisals and social support were key predictors of coping with interpersonal stress in this population.
210

Leadership Theory and Practice in Sport Management: What Constitutes Ethical Leadership According to Student-Interns?

Clack, Justin Tyler 16 December 2013 (has links)
Due to the multitude of widely publicized scandalous acts exhibited by managers in the sport industry, there is a pressing need for leadership philosophies and styles that embody ethical behavior. The standard for effective leadership among scholars and practitioners has recently shifted to include ethical behavior as a valuable asset. Thus, the purpose of this thesis is to understand what constitutes ethical leadership in contemporary sport organizations and academic curricula geared toward sport management. This qualitative study explored ethical leadership from the perspective of 13 undergraduate students (e.g., student-interns) majoring in sport management who have acquired experience in an academic environment and business setting. Semi-structured, face-to-face interviews were conducted with each of the student-interns. Bandura’s (1977) social learning theory, which is grounded in the notion that individuals learn by observing the behaviors of dependable models, was utilized to construct interview questions for this study. Findings revealed the ethical attitudes and behaviors of student-interns are heavily influenced by leaders in academic and organizational settings. Essentially, the ethical standards held by student-interns reflected the opinions and actions of valued faculty members and sport managers. In contrast to the widespread unethical leadership on display in contemporary sport, participants in this study indicated ethical conduct was the prevailing norm within academic and business settings. However, after analyzing data, there were notable discrepancies between theoretical and practical dimensions of ethical leadership in the sporting realm. This thesis contributes to the ongoing discourse concerning the level of continuity between theory and practice as it pertains to ethical leadership in sport. Findings from this study are discussed as it relates to the future ethical climate in the sport industry and academic environment.

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