Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2008. / Source: Dissertation Abstracts International, Volume: 69-05, Section: B, page: 2883. Advisers: Karl Rosengren; Elizabeth Hsiao-Wecksler. Includes bibliographical references (leaves 133-142) Available on microfilm from Pro Quest Information and Learning.

Cam femoroacetabular impingement (FAI) is caused by decreased concavity of the femoral head-neck junction which results in a jamming of the proximal femur into the acetabulum within normal range of motion (ROM). This condition is known to decrease hip ROM, and has been reported to cause hip pain in a variety of daily activities including sitting and walking, and activities requiring large hip mobility. It is important to determine the effect of cam FAI on self-generated dynamic ROM and common daily activities in order to ascertain its influence on hip functionality. This study measured the effect of cam FAI on total dynamic hip ROM, and the biomechanics of the hip and pelvis during walking, sitting, standing and maximal depth squats. A cam impingement group (n = 17) was compared to a matched control group (n = 14) using between-group one-way ANOVAs. The level of variability for sitting and standing strategies was also compared between the two groups using F-tests. For maximal dynamic hip mobility, the FAI group had a decreased flexed internal rotation, external rotation and total transverse ROM, as well as decreased hip abduction and total sagittal ROM compared to the matched control group. For walking, the FAI had significantly lower peak hip abduction, frontal ROM, and sagittal ROM than the controls, as well as attenuated pelvic frontal ROM. Reduced hip mobility during gait may be caused by soft tissue restriction, and FAI participants may have decreased pelvic mobility in the frontal plane. For the sit-to-stand and stand-to-sit manoeuvres there were no significant differences in peak kinematic or kinetic values of the hip and pelvis between the two groups. However, the cam FAI group had significantly higher variability in peak angles in the frontal plane, and peak hip extension moments of force during both sitting and standing. This likely resulted from the FAI group having varying sit and stand compensatory strategies. For the 2 maximal depth squat the FAI group had decreased sagittal pelvic range of motion and could not squat as deep as the control group. Limited pelvic ROM in FAI patients reduces their capacity to perform motions requiring large amplitudes at the hip joint such as maximum squat. Restricted pelvic sagittal ROM could represent a key factor in the pathomechanics of FAI.

In this thesis, I focus on Southern African peer educators' experiences in facilitating HIV/AIDS education activities within the Kicking AIDS Out network. By utilizing Foucault's (1975) conception of "subjugated knowledges," I work towards four main objectives. In chapter one, I aim to surface a sample of young people's subjugated knowledges pertaining to the "lack of evidence" discourse of sport for development. In chapter two, my objective was to understand better what tools peer educators need to be more effective in their HIV/AIDS education efforts in a sport environment. Chapter three suggests steps to encourage knowledge exchange on sport for development across geographical and cultural boundaries to further national HIV/AIDS education and health goals with Aboriginal communities. I meet my fourth objective, to provide recommendations to the Kicking AIDS Out network regarding the training and support needs of peer educators in a field report, which is not contained in this thesis.

Impact mass and inbound velocity are important parameters defined in helmet standards, which represent the total energy transferred during a hit to the head. The purpose of this study was to determine the influence that impact mass and inbound velocity had on energy attenuation characteristics of polymeric materials used in helmet design. Materials consisted of three densities of expanded polystyrene, expanded polypropylene, and vinyl nitrile foam. Each sample was impacted once at 25 different levels of energy using a monorail drop test. Significant main effects were observed for impact mass, inbound velocity, and material density on peak linear acceleration and impulse (p<0.05). Using peak linear accelerations as the determinant for risk of injury, head mass and inbound velocity played a significant role in helmet material performance.

The purpose of this thesis was to explore young Shia Muslim Canadian women's discursive constructions of physical activity in relation to Islam and the Hijab. The aims of the study were primarily informed by feminist poststructuralist and postcolonial theories. Qualitative methods were favored and poststructuralist discourse analysis was used to analyze the transcripts of conversations with 10 young Hijab-wearing Shia Muslim women residing in the Ottawa or Toronto regions. The results show that the participants discursively constructed physical activity in terms of being physically active (involved in fitness activities rather than sport), feeling good about themselves (i.e., being physically and mentally healthy), and losing weight or remaining "not fat." The participants were extremely heterogeneous in their ideas and experiences but, nevertheless, a majority mentioned that they would choose Islam over physical activity if they had to make a choice between the two. Wearing the Hijab while participating in physical activity was seen by most as difficult and limiting but, in the end, neither the Islamic religion nor the Hijab were considered barriers to physical activity. Participants strongly resisted the Islamophobic discourse present in Canada, they appealed to a discourse dominant in their own communities that presents a relatively progressive interpretation of the Quran and they constructed themselves as modern Muslim subjects yet they located themselves within a dominant gendered/religious discourse on women and physical activity. In the end, the young Shia Muslim women appropriated an intersectional discourse that legitimates their refusal to choose between their right to religious freedom and their right to physical activity.

The majority of children in the United States do not attain the recommended sixty minutes of daily physical activity. Opening up school facilities outside of school hours for use by the community has been suggested to increase opportunities for physical activity. The purpose of this research was to identify social and environmental factors that influence community use policies and practices in Massachusetts school districts. Paper 1 developed a quantitative index to describe differences in community use policies. Written community use policies from Massachusetts school districts were collected and double-coded. Analysis of variance was used to identify differences between template vs. unique policies. Districts that developed unique policies had significantly higher scores than districts that adopted the template (mean 20.8 vs. 16.5, P < 0.05). Paper 2 aimed to identify how community use policy presence and sociodemographic characteristics were associated with access to low- and no-cost recreation areas in Massachusetts school districts. Geographic information systems software was used to identify key variables. Linear regression was used to determine if geographic location or district-level sociodemographic characteristics were associated with recreational area availability. In adjusted analyses, metropolitan districts had 2.51 more acres of recreational area surrounding schools per 1000 residents compared to non-metropolitan districts (P = 0.003). Paper 3 utilized a mixed methods approach to identify differences in community use practices in high-use vs. low-use districts. An online survey of school district administrators was conducted, and a subset of these administrators participated in follow-up telephone interviews. The online survey results showed that high-use districts provided a significantly wider variety of services through community use agreements compared to low-use districts (P = 0.02). Both high-use and low-use districts cited cost, maintenance, and upkeep as the biggest barriers to community use. This dissertation created an index that provides a systematic and reliable way to assess school district community use policies. Additionally, it identified disparities in access to recreational and school facilities for physical activity in non-metropolitan school districts in Massachusetts, and identified cost, maintenance, and upkeep as significant barriers to increasing community use. Training, technical assistance, and future research should focus on these areas.

Indoor group cycling (IGC) is a popular type of aerobic activity performed on a stationary bike, combining both mental and physical aspects of training through the use of imagery (Johnny G. Spinning Instructor Manual, 1999). Thompson, Durand-Bush, & O'Sullivan, (2003) investigated the different types of imagery cues provided by instructors and their effects on the overall IGC experience. However, the purpose of this study was to examine the effectiveness of imagery cues provided by IGC instructors, as perceived by class participants. The sample included four certified IGC instructors and 15 class participants. The instructors were videotaped while teaching their IGC class, after which class participants completed a questionnaire, took part in a stimulated recall session (Calderhead, 1981), and participated in a semi-structured interview to assess the effectiveness of the imagery cues provided by the instructors. Nine categories and three sub-categories of cues were provided in varying frequencies by the instructors however, the class participants found only certain types to be effective. They preferred simple cues that were given following a logical progression and were synchronized with the music. Several practical implications and suggestions for future research are discussed.

Purpose. Study #1 examined the responses to facial immersion under states of altered cardiac filling. Study #2 sought to examine changes in postexercise hemodynamics and skin blood flow (SkBF) when lower blood pooling was manipulated using lower body pressure. Methods. Study #1---Six male subjects participated. They performed 30-s apneic facial immersions under: LBNP, LBPP, during post-exercise hypotension (PEH); & Control. MAP, HR, and SkBF were measured. Study #2---Subjects were exposed to LBNP, LBPP; or no pressure after 15-mins of cycle exercise at 70% of VO2 peak. HR, CO, SV, MAP, TPR, & SkBF, skin and esophageal temperature were recorded. Conclusions. Study #1---Cardiac parasympathetic response during facial immersion can be attenuated when cardiac filling is compromised. Study #2---(1) LBPP accelerates recovery of baseline hemodynamics while LBNP exacerbates the postexercise hemodynamic state relative to control. (2) Altering postexercise hemodynamics via LBPP may affect thermal responses.

Il a été démontré que l'intensité de l'exercice influence l'apport énergétique chez les hommes. L'objectif principal de cette étude portrait sur l'investigation des effets de l'intensité de l'exercice sur la prise alimentaire, la préférence macronutritionnelle, l'appétit et le profil hormonal chez des jeunes femmes. Treize jeunes femmes de poids normal et modérément actives ont participé à trois conditions expérimentales: Contrôle (C) sans exercice et deux sessions d'exercice équicaloriques (350 kilocalories), soit à faible (EFI) et haute (EHI) intensité, pratiquées à 40% et 70% de la consommation maximale d'oxygène (VO 2 peak), respectivement. À la suite de chacune de ces sessions, deux buffets (dîner et souper) ainsi que des collations (en après-midi et en soirée) ont été offerts aux participantes, qui pouvaient manger à volonté les aliments qui leurs étaient présentés. (Abstract shortened by UMI.)

We compared changes in thigh muscle cross sectional area (CSA), strength, VO2peak, and HbA1c following aerobic training (A), resistance training (R), or their added combination (AR) in 115 sedentary type 2 diabetic men and women. Participants aged 40 to 70 years, mean BMI of 33.5 kg/m2, were randomly assigned to 6 months of 3x/wk A only (17 M, 11 W), R only (17 M, 11 W), combined AR (17 M; 12 W), and waiting-list control (C) (17 M, 13 W). All exercising men increased mid-thigh CSA (all p &lt; 0.05). Mean increases in VO2peak were exhibited in A and AR men (8.4% and 7.3%; p &lt; 0.05). Strength increases were similar for exercising men and women. Absolute HbA1c decreased in AR men (1.22%) and women (0.62%), and A men (0.80%) (all p &lt; 0.05). R men exhibited a greater relative reduction in HbA1c as compared to R women (p = 0.033 between sexes). Exercising men had modestly greater improvements in HbA1c than women.