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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.
221

The Catastrophe Artists: Understanding America’s Unaccountable Foreign Policy Elite

Fraser, Samuel 01 January 2019 (has links)
The 2003 U.S. invasion of Iraq was a foreign policy action that violated international law, was based on false premises, and came to represent a clear and costly political disaster for the United States and Iraq. Why then, did none of the top policymakers responsible for the decision to invade face meaningful consequences – be they professional consequences, or legal ones? Why too have so many of the media figures who helped sell this war to the American public remained in their prestigious positions, with massive platforms to influence the American people? This paper argues that the above groups, referred to as the foreign policy elite or foreign policy establishment, are granted a general impunity for their actions. It seeks to explain this condition of elite impunity, and how it operates, through Robert Putnam’s theory of “elite integration.” It also examines the role of congressional marginalization and public disengagement in enabling the foreign policy elite to escape accountability. The subsequent chapters offer case studies of how each of these factors has helped advance and preserve the careers of two prominent members of the foreign policy elite, Elliott Abrams and Henry Kissinger. Finally, the conclusion explores further questions on the matter of elite impunity, and offers some basic steps towards creating a more accountable foreign policy elite.
222

The validation of physiological field testing in elite orienteers

Rattray, Benjamin, n/a January 2002 (has links)
The complex physiology of orienteering performance is not well understood but recent advances in technology allow for more in-depth investigation. The purpose of this study was to develop and validate physiological field tests for elite orienteers in Australia. Seven male and three female elite orienteers volunteered to take part in the study. Subjects completed an incremental fixed-distance (803m) trial in Australian forest terrain, paced by a bicycle equipped with a speedometer. This was replicated in the laboratory using a 4.5% grade for treadmill running. Subjects also completed four (males) or three (females) laps of a 1340m terrain loop incorporating uphill, track and downhill sections. Subjects then repeated this test in the laboratory, with treadmill grade manipulated to replicate the gradient profile of each section. Heart rate (HR) and oxygen uptake (VCh) were recorded continuously with telemetry during each stage/lap. Blood [La] and RPE were recorded after each stage/lap. In the incremental tests, no significant differences (p=0.05 level) were observed in HR, VO2, blood [La] or RPE between the Field test, and its Laboratory replication over the entire range of speeds tested. The actual speeds run during the Field tests were significantly faster than the Laboratory test at the slowest speed (8 kmh- 1 ) attempted, and slower at the fastest speed (18 km-h-1) attempted. In the time-trial tests, no significant differences were observed in HR, VO2, blood [La] or RPE between the Field test and its Laboratory replication. The running speeds in the Field tests were significantly slower than the Laboratory tests. Running speed appeared inversely related to the course profile and the terrain also affected the speeds that could be achieved. Despite the changes in the course profile, the physiological responses to the course were maintained within a narrow range at a high level (-95% of maximal heart rate, 80-90% of VO2max, blood [La] -10 mM) for the duration of the 20-25 minute test. The Field tests that were developed in this study for elite orienteers in Australian forest terrain were successfully validated by replicating the protocols in a Laboratory setting.
223

The organisation and structure of elite junior sport in the ACT

Campbell, Joseph, n/a January 1993 (has links)
None Provided.
224

Performance and Physiological Monitoring of Highly Trained Swimmers

Anderson, Megan, n/a January 2006 (has links)
This thesis examined the benefits of physiological and performance testing of elite swimmers. The study considered the following research questions: the degree to which physiological and performance measures in training contribute to swimming performance; sources and magnitude of variability in testing, training and competition performance; the magnitudes of changes in test measures during routine training; and the reliability, validity and utility of miniaturised and automated smart sensor technology to monitor the stroke and performance times of swimmers in training. The experimental approach involved the retrospective analysis of five years of physiological and performance testing of elite level swimmers, the development of a new accelerometry-based smart sensor device to monitor swimmers in the pool, a cross-sectional study comparing the physiological and performance responses of swimmers of different levels, and the effects of an intensive 14-day training program on submaximal physiological and performance measures. Collectively, the outcomes of these studies provide a strong justification for the physiological and performance testing of elite swimmers, a quantitative framework for interpreting the magnitude of changes and differences in test scores and sources of variation, and highlight the potential utility of new smart sensor technology to automate the monitoring of a swimmer�s training performance. The first study (Chapter 2) characterises the changes and variability in test performance, physiological and anthropometric measures, and stroke mechanics of swimmers within and between seasons over their elite competitive career. Forty elite swimmers (24 male, 16 female) performed a 7 x 200-m incremental swimming step test several times each 6-month season (10 � 5 tests, spanning 0.5 to 6.0 y). Mixed linear modeling provided estimates of change in the mean and individual responses for measures based on submaximal performance (fixed 4-mM lactate), maximal performance (the seventh step), and lean mass (from skinfolds and body mass). Submaximal and maximal swim speed increased within each season from the pre to taper phase by ~2.2% for females and ~1.5% for males (95% confidence limits �1.0%), with variable contributions from stroke rate and stroke length. Most of the gains in speed were lost in the off-season, leaving a net average annual improvement of ~1.0% for females and ~0.6% for males (�1.0%). For submaximal and maximal speed, individual variation between phases was �2.2% and the typical measurement error was �0.8%. In conclusion, step test and anthropometric measures can be used to confidently monitor progressions in swimmers in an elite training program within and between seasons. The second study (Chapter 3) quantified the relationship between changes in test measures and changes in competition performance for individual elite swimmers. The primary question addressed was whether test measures could predict a swimmers performance at the major end-of-season competition. The same sample group as in Study 1 was examined. A 7 x 200-m incremental swimming step-test and anthropometry were conducted in up to four training phases each season. Correlations of changes in step-test and anthropometric measures between training phases between and within seasons, with changes in competition performance between seasons, were derived by repeated-measures mixed modeling and linear regression. Changes in competition performance were best tracked by changes in test measures between taper phases. The best single predictor of competition performance was skinfolds for females (r = -0.53). The best predictor from the step-test was stroke rate at 4-mM lactate (females, r = 0.46; males, r = 0.41); inclusion of the second-best step-test predictor in a multiple linear regression improved the correlations marginally (females, r =0.52 with speed in the seventh step included; males, r = 0.58 with peak lactate concentration included). Changes in test measures involving phases other than the taper provided weak and inconclusive correlations with changes in performance, possibly because the coaches and swimmers took corrective action when tests produced poor results. In conclusion, a combination of fitness and techniques factors are important for competitive performance. The step test is apparently a useful adjunct in a swimmer�s training preparation for tracking large changes in performance. These initial studies identified stroke mechanics as a major determinant of a swimmer�s performance. Chapter 4 details the development of a small tri-axial accelerometry-based smart sensor device (the Traqua) that enables continual monitoring of various performance/stroke characteristics in swimming. The initial focus was to develop a device that automated the detection of a swimmer�s movements, specifically lap times, stroke rate and stroke count. The Traqua consists of a tri-axial accelerometer packaged with a microprocessor, which attaches to the swimmer at the pelvis to monitor their whole body movements while swimming. This study established the failure/error rate in the first generation algorithms developed to detect the swimming-specific movements of stroke identification, laps (start, turn and finish), and strokes (stroke count and stroke rate) in a cohort of 21 elite and sub-elite swimmers. Movements were analysed across a range of swimming speeds for both freestyle and breaststroke. These initial algorithms were reasonably successful in correctly identifying the markers representing specific segments of a swimming lap in a range of swimmers across a spectrum of swimming speeds. The first iteration of the freestyle algorithm produced error-rates of 13% in detection of lap times, 5% for stroke rate, and 11% for stroke count. Subsequent improvements of the software reduced the error rate in lap and stroke detection. This improved software was used in the following two studies. The next study (Chapter 5) evaluated the reliability and validity of the Traqua against contemporary methods used for timing, stroke rate and stroke count determination. The subjects were 14 elite and 10 sub-elite club-level swimmers. Each swimmer was required to swim seven evenly paced 200-m efforts on a 5-min cycle, graded from easy to maximal. Swimmers completed the test using their main competitive stroke (21 freestyle, 3 breaststroke). Timing was compared for each 50-m lap and total 200-m time by electronic touch pads, video coding, a hand-held manual stopwatch, and the Traqua. Stroke count was compared for video coding, self-reported counting, and the Traqua, while the stroke rate was compared via video coding, hand-held stopwatch, and the Traqua. Retest trials were conducted under the same conditions 7 d following the first test. All data from the Traqua presented in this and the subsequent studies were visually inspected for errors in the automated algorithms, where the algorithms had either failed to correctly identify the start, turn, finish or individual strokes and corrected prior to analysis. The standard error of the estimate for each of the timing methods for total 200 m was compared with the criterion electronic timing. These standard errors were as follows: Traqua (0.64 s; 90% confidence limits 0.60 � 0.69 s), Video (0.52 s; 0.49 � 0.55 s); Manual (0.63 s; 0.59 � 0.67 s). Broken down by 50-m laps, the standard error of the estimate for the Traqua compared with the electronic timing for freestyle only was: 1st 50-m 0.35 s; 2nd and 3rd 50-m 0.13 s; 4th 50-m 0.65 s. When compared with the criterion video-coding determination, the error for the stroke count was substantially lower for the Traqua (0.6 strokes.50 m-1; 0.5 � 0.6 strokes.50 m-1) compared to the self-reported measure (2.3 strokes.50 m-1; 2.5 � 2.9 strokes.50 m-1). However, the error for stroke rate was similar between the Traqua (1.5 strokes.min-1; 1.4 � 1.6 strokes.min-1) and the manual stopwatch (1.8 strokes.min-1; 1.7 � 1.9 strokes.min-1). The typical error of measurement of the Traqua was 1.99 s for 200-m time, 1.1 strokes.min-1 for stroke rate, and 1.1 strokes.50 m-1 for stroke count. In conclusion, the Traqua is comparable in accuracy to current methods for determining time and stroke rate, and better than current methods for stroke count. A substantial source of error in the Traqua timing was additional noise in the detection of the start and finish. The Traqua is probably useful for monitoring of routine training but electronic timing and video are preferred for racing and time trials. Having established the reliability and validity of the Traqua, Chapter 6 addressed the ability to discriminate the pattern of pacing between different levels of swimmers in the 7 x 200-m incremental step test. This study also sought to quantify the differences in pacing between senior and junior swimmers. Eleven senior elite swimmers (5 female, 6 male) and 10 competitive junior swimmers (3 female, 7 male) participated in this study. Each swimmer was required to swim seven evenly paced 200-m freestyle efforts on a 5-min cycle, graded from easy to maximal. The Traqua was used to measure time, stroke rate and stroke count. The senior swimmers were better able to descend in each of the 200-m efforts. Overall the senior swimmers were ~2-3 s per 50 m faster than the junior swimmers. Both groups were fastest in the first 50-m lap with the push start. The senior swimmers then descended the 50- m time for each of the subsequent laps, getting ~0.5 s faster per lap, with the final lap the fastest. In contrast, the junior swimmers swam a similar time for each of the subsequent laps. The junior swimmers were marginally more variable in their times (coefficient of variation: ~2%) compared with the senior swimmers (~1.8%). In comparison to junior swimmers, the senior swimmers in this study were faster, adopted a more uniform negative split strategy to pacing within a 200-m effort, and were more consistent in reproducing submaximal and maximal swimming speeds. The final study (Chapter 7) analysed the effect of 14-d of intensive training on the reproducibility of submaximal swimming performance in elite swimmers. Submaximal physiological and performance testing is widely used in swimming and other individual sports but the variability in test measures, and the effects of fatigue, during intensive training have surprisingly not been quantified systematically. Seven elite swimmers (3 male and 4 female) participated in an intensive 14-d training camp one month prior to the National championships. The aim of the study was to characterise the intra-session, daily and training block variability of submaximal swimming time, physiological and stroke characteristics in elite swimmers. The swimmers performed a specified submaximal 200-m effort in most sessions, after the warm-up and at the end of the session for both morning and afternoon sessions. During the efforts, swimming time and stroke mechanics were measured and physiological measures were recorded immediately on completion. The Traqua was worn by all swimmers in every training session. Mixed linear modeling was used to provide estimates of changes in the mean and individual responses (within-athlete variation as a coefficient of variation) for all measures. The swimmers were moderately slower (1.4%; �1.4%) over the 14-d training camp. The mean submaximal 200-m effort was very likely to be faster (0.7%; confidence limits �0.7%) in the afternoon compared with the morning session. The females were more variable in their submaximal performance times (CV=2.6%) than the male swimmers (1.7%). Blood lactate concentration was almost certainly lower (-23%; �10%) following higher volume in the previous session; however a higher intensity workout the previous session almost certainly leads to higher lactate (21%; �15%) in the current session. Considered together, these results indicate that the 200-m submaximal test is useful in monitoring submaximal physiological and performance measures and the negative effects of cumulative fatigue. In conclusion, changes in the physiological and performance measures derived from the poolbased progressive incremental step test are moderately correlated with changes in end-ofviii. season competition performance. The magnitudes of changes and differences in test measures between phases within a season, from season to season, and between males and females, established in this study can be applied to similar elite level swimmers preparing for major competition. The quantification of typical error of the same measures demonstrates that coaches and scientists can distinguish real and worthwhile improvements using the 7 x 200-m step test. Continual pool-based monitoring with the automated smart sensor Traqua device may provide more accurate and detailed information about a swimmer�s training adaptation than current fitness tests and monitoring methods. Finally, submaximal testing in trained swimmers is useful in monitoring progress in physiological and performance measures, and the impact of cumulative fatigue during an intensive period of training. Collectively, the outcomes of these studies indicate that routine physiological and performance testing can provide measurable benefits for elite swimmers and their coaches.
225

Crossing Boundaries: Suzuki Bokushi (1770-1842) and the Rural Elite of Tokugawa Japan

T.Moriyama@murdoch.edu.au, Takeshi Moriyama January 2008 (has links)
This thesis centres on a member of the rural elite, Suzuki Bokushi (1770-1842) of Echigo, and his social environment in Tokugawa Japan (1603-1868). Through a case study of the interaction between one individual’s life and his social conditions, the thesis participates in the ongoing scholarly reassessment of Tokugawa society, which had an apparently rigid political and social structure, yet many features that suggest a prototype of modernity. Bokushi’s life was multifaceted. He was a village administrator, landlord, pawnbroker, poet, painter, and great communicator, with a nation-wide correspondence network that crossed various social classes. His remote location and humble lifestyle notwithstanding, he was eventually able to publish a book about his region, Japan’s ‘snow country’. This thesis argues that Bokushi’s life epitomises both the potentiality and the restrictions of his historical moment for a well-placed member of the rural elite. An examination of Bokushi’s life and texts certainly challenges residual notions of the rigidity of social boundaries between the urban and the rural, between social statuses, and between cultural and intellectual communities. But Bokushi’s own actions and attitudes also show the force of conservative social values in provincial life. His activities were also still restrained by the external environment in terms of geographical remoteness, infrastructural limitation, political restrictions, cultural norms and the exigencies of human relationships. Bokushi’s life shows that in his day, Tokugawa social frameworks were being shaken and reshaped by people’s new attempts to cross conventional boundaries, within, however, a range of freedom that had both external and internal limits.
226

Makten på Öland och i Möre : Järnålderns elit i ett lokalt perspektiv

Karlsson, Simon January 2008 (has links)
<p>The social elite on Öland and in Möre in the south east of Sweden during the Iron Age is described on the basis of the archaelogical record, such as graves, settlements and traces of pre-Christian central places. The material is discussed to see if traces of an elite are to be found. The power configuration between Öland and Möre is also discussed.</p><p> </p>
227

GIS - A Potential Tool for Development in Babati

Andersson Wargert, Gunnar January 2009 (has links)
<p>The Geographical Information System (GIS) is a popular tool among landscape plannersas well as administration departments on both local as well as national level. It is asystem that can store and manipulate spatial data and its potential has increased ascomputers have grown to be more and more sophisticated. However the system is notwithout its controversy. Maps and geographical information has been accused of helpinggovernment maintaining its power thus leading to increased surveillance in society. As arespond to this critique Public Participatory Geographical Information System (PPGIS)was developed. PPGIS quickly grew and has been implemented in a wide variety ofprojects. The purpose of this paper is to explore to what extent these aspect plays a partin the implementation of GIS and PPGIS in Babati, Tanzania. More specifically, couldBabati handle a complex and resource demanding system such as GIS? To clarify howGIS could play a beneficial part in Babati development, a high rate in population growthas well as department clashes will be illustrating examples. In Babati there have beenrepeatedly conflicts between the water department and the Babati town council and someof them are directly related to communication issues. A hypothesis suggests that GIS haspotential in creating cohesion and a communication tool operating through geographicaldata. In generally results show that GIS could lead to better development, but at the sametime risk alienating people from participating in the decision making. Consequently ifGIS would be effective in Babati, it would have to be adapted to the region it is appliedto, funded on the towns’ resources and knowledge. If it does not it risks failing in thelong term as well as not living up to expected standard. PPGIS could possibly avoid someof the issues that might appear when implementing GIS but it is unlikely that it has all theanswers. PPGIS can improve the situation for marginalized people but a societyundemocratic issue is more likely to stem from several of different aspects.</p>
228

Análisis descriptivo de la evolución de la élite cruceña en élite regional (periodo 1952 - 2005)

Verduguez Linares, René Efrain January 2010 (has links)
Se presenta a continuación la investigación denominada “Análisis Descriptivo de la Evolución de la Élite Cruceña en Élite Política Regional (1952 – 2005)”, misma que pretende clarificar todas las dudas surgidas en base a los grupos de poder del oriente del país, y especialmente del departamento cruceño. El estudio contempla las categorías conceptuales pertinentes para comprender la temática, así como la identificación de un problema de investigación solucionado, provisionalmente, por una hipótesis de trabajo que se someterá a prueba a lo largo del marco práctico a través de sus variables dependiente e independiente. Finalmente, los requisitos metodológicos y las fuentes de información disponibles conforman parte indispensable para lograr los niveles de calidad científica a los que se desean arribar con la temática seleccionada, misma que se encuentra motivada por la imperante necesidad de conocer otra de las facetas de la realidad boliviana
229

The relationship of gymnastics participation in childhood and adolescence to skeletal development and maintenance

Erlandson, Marta Christine 25 January 2011
Osteoporosis, through its association with age-related fracture, is a major public health concern worldwide. Although osteoporosis was once considered a disease of the elderly, it is now recognized as a condition that has childhood antecedents. The capacity of bone to adapt is the greatest before puberty because of a higher rate of modeling and remodeling. Therefore, the amount of bone gained during childhood and adolescence has the potential to impact lifetime skeletal health. Children who participate in greater amounts of physical activity have greater bone mineral accrual in adolescence as well as a greater peak bone mass in young adulthood. Structured impact loading during growth also positively influences bone parameters. However, the intensity, duration and frequency of loading that is required to elicit skeletal benefits are not well established. Furthermore, although structured physical activity during growth has been hypothesized to delay or prevent the risk of osteoporosis and related fracture later in life there is no clear evidence of a persisting benefit once the loading stimulus has been removed. Therefore, the objective of this thesis was to investigate low-level impact loading during growth and skeletal development as well as to determine the influence of the withdrawal of the loading stimulus on adult bone parameters. Two studies were necessary to realize this objective. The findings should help to determine whether adolescent and adult bone health benefits from structured physical activity during growth. If this is found to be the case then structured gymnastic activity could be promoted as an effective means to optimize adult bone mass, structure and estimated strength.<p> Study 1: The purpose of study one was to investigate whether the differences previously reported in the skeleton of competitive female gymnasts (high level gymnastics exposure) are also demonstrated in young children with a current or past participation history in recreational or precompetitive gymnastics (low level gymnastics exposure). One hundred and sixty three children (30 gymnasts, 61 ex-gymnasts, and 72 non-gymnasts) between 4 and 6 years of age were recruited and measured annually for four years. Total body (TB), lumbar spine (LS) and femoral neck (FN) bone mineral content (BMC) was measured by dual energy x-ray absorptiometry (DXA) at each measurement occasion. Bone mass, density, structure and estimated strength was determined using peripheral quantitative computed tomography (pQCT) at the radius and tibia during the third measurement occasion. Multilevel random effects models were constructed and used to predict differences in TB, LS and FN BMC between groups while controlling for differences in body size, physical activity and diet. Analysis of covariance (covariates of sex, age and height) was used to investigate differences in bone content, density, area, and estimated strength at the radius and tibia. Gymnasts had 3% more TB and 7% more FN BMC than children participating in other recreational sports at the fourth measurement occasion (p<0.05). Gymnasts were also found have 6-25% greater adjusted BMC, volumetric bone mineral density and estimated strength at the distal radius compared to non-gymnasts (p<0.05). These findings suggest that recreational and precompetitive gymnastics participation (low level gymnastics exposure) is associated with greater bone parameters. This is important as beginner gymnastics skills are attainable by most children and do not require a high level of training. Low-level gymnastics skills can easily be integrated into school physical education programs potentially impacting skeletal health.<p> Study 2: The purpose of study 2 was to assess whether the previously reported greater bone mineral content in premenarcheal gymnasts was maintained 10 years after the cessation of participation and removal of the gymnastics loading stimulus. In 1995, thirty elite premenarcheal female gymnasts were recruited into a study investigating the role of high impact physical activity on bone mass in childhood and compared to 30 non-gymnasts. In 2009-2010 gymnasts and non-gymnasts (n=60) were re-contacted and 25 retired gymnasts and 22 non-gymnasts consented to participate. Total body, LS, and FN BMC was assessed at both measurement occasions by DXA. Bone geometric and densitometric parameters were measured by pQCT at the radius and tibia in 2009/10. ANCOVA was used to compare gymnasts and non-gymnasts bone parameters while controlling for differences in age, body composition and maturation. Gymnasts had significantly greater size adjusted TB, LS, and FN BMC (15, 17, and 12%, respectively) at 12 years of age (1995) (p<0.05). At follow-up, retired gymnasts also had significantly greater size adjusted TB, LS, and FN BMC (13, 19 and 13%, respectively) (p<0.05). Furthermore, retired female gymnasts had greater bone area, content and estimated strength at the radius and greater BMC and estimated strength at the tibia compared to non-gymnasts (p<0.05). Premenarcheal gymnasts have bone benefits that were apparent in adulthood after long-term removal of the gymnastics loading stimulus. Low level gymnastics exposure was associated with greater bone parameters in childhood. If these benefits can be maintained, as is suggested in retired competitive gymnasts, recreational gymnastics participation has the potential to positively impact lifetime skeletal health.
230

The relationship of gymnastics participation in childhood and adolescence to skeletal development and maintenance

Erlandson, Marta Christine 25 January 2011 (has links)
Osteoporosis, through its association with age-related fracture, is a major public health concern worldwide. Although osteoporosis was once considered a disease of the elderly, it is now recognized as a condition that has childhood antecedents. The capacity of bone to adapt is the greatest before puberty because of a higher rate of modeling and remodeling. Therefore, the amount of bone gained during childhood and adolescence has the potential to impact lifetime skeletal health. Children who participate in greater amounts of physical activity have greater bone mineral accrual in adolescence as well as a greater peak bone mass in young adulthood. Structured impact loading during growth also positively influences bone parameters. However, the intensity, duration and frequency of loading that is required to elicit skeletal benefits are not well established. Furthermore, although structured physical activity during growth has been hypothesized to delay or prevent the risk of osteoporosis and related fracture later in life there is no clear evidence of a persisting benefit once the loading stimulus has been removed. Therefore, the objective of this thesis was to investigate low-level impact loading during growth and skeletal development as well as to determine the influence of the withdrawal of the loading stimulus on adult bone parameters. Two studies were necessary to realize this objective. The findings should help to determine whether adolescent and adult bone health benefits from structured physical activity during growth. If this is found to be the case then structured gymnastic activity could be promoted as an effective means to optimize adult bone mass, structure and estimated strength.<p> Study 1: The purpose of study one was to investigate whether the differences previously reported in the skeleton of competitive female gymnasts (high level gymnastics exposure) are also demonstrated in young children with a current or past participation history in recreational or precompetitive gymnastics (low level gymnastics exposure). One hundred and sixty three children (30 gymnasts, 61 ex-gymnasts, and 72 non-gymnasts) between 4 and 6 years of age were recruited and measured annually for four years. Total body (TB), lumbar spine (LS) and femoral neck (FN) bone mineral content (BMC) was measured by dual energy x-ray absorptiometry (DXA) at each measurement occasion. Bone mass, density, structure and estimated strength was determined using peripheral quantitative computed tomography (pQCT) at the radius and tibia during the third measurement occasion. Multilevel random effects models were constructed and used to predict differences in TB, LS and FN BMC between groups while controlling for differences in body size, physical activity and diet. Analysis of covariance (covariates of sex, age and height) was used to investigate differences in bone content, density, area, and estimated strength at the radius and tibia. Gymnasts had 3% more TB and 7% more FN BMC than children participating in other recreational sports at the fourth measurement occasion (p<0.05). Gymnasts were also found have 6-25% greater adjusted BMC, volumetric bone mineral density and estimated strength at the distal radius compared to non-gymnasts (p<0.05). These findings suggest that recreational and precompetitive gymnastics participation (low level gymnastics exposure) is associated with greater bone parameters. This is important as beginner gymnastics skills are attainable by most children and do not require a high level of training. Low-level gymnastics skills can easily be integrated into school physical education programs potentially impacting skeletal health.<p> Study 2: The purpose of study 2 was to assess whether the previously reported greater bone mineral content in premenarcheal gymnasts was maintained 10 years after the cessation of participation and removal of the gymnastics loading stimulus. In 1995, thirty elite premenarcheal female gymnasts were recruited into a study investigating the role of high impact physical activity on bone mass in childhood and compared to 30 non-gymnasts. In 2009-2010 gymnasts and non-gymnasts (n=60) were re-contacted and 25 retired gymnasts and 22 non-gymnasts consented to participate. Total body, LS, and FN BMC was assessed at both measurement occasions by DXA. Bone geometric and densitometric parameters were measured by pQCT at the radius and tibia in 2009/10. ANCOVA was used to compare gymnasts and non-gymnasts bone parameters while controlling for differences in age, body composition and maturation. Gymnasts had significantly greater size adjusted TB, LS, and FN BMC (15, 17, and 12%, respectively) at 12 years of age (1995) (p<0.05). At follow-up, retired gymnasts also had significantly greater size adjusted TB, LS, and FN BMC (13, 19 and 13%, respectively) (p<0.05). Furthermore, retired female gymnasts had greater bone area, content and estimated strength at the radius and greater BMC and estimated strength at the tibia compared to non-gymnasts (p<0.05). Premenarcheal gymnasts have bone benefits that were apparent in adulthood after long-term removal of the gymnastics loading stimulus. Low level gymnastics exposure was associated with greater bone parameters in childhood. If these benefits can be maintained, as is suggested in retired competitive gymnasts, recreational gymnastics participation has the potential to positively impact lifetime skeletal health.

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