Kinesiology Theses and Dissertations
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- ItemSIMILAR VASCULAR RESPONSES TO A HIGH-FAT MEAL, REGARDLESS OF RACE AND SOCIAL DETERMINANTS OF HEALTH(2022) Weiner, Cynthia Marie; Ranadive, Sushant M; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Black individuals are at a higher risk for developing cardiovascular disease (CVD), including hypertension, compared to white individuals. Chronic low-grade inflammation contributes to hypertension by causing vascular dysfunction, including increased vascular resistance. Young, healthy, normotensive black individuals exhibit heightened inflammatory biomarkers at rest, a possible factor in the higher prevalence of hypertension seen within this population. Vascular function decreases transiently as a result of an acute inflammatory stimulus, such as with consumption of a high-fat meal (HFM). However, there is limited evidence regarding the racial differences in inflammatory and vascular responses to a HFM in young, healthy black and white individuals. Furthermore, there are limited data regarding the association between social determinants of health (SDH) factors and the physiological components of inflammation and vascular responses. Therefore, the goal of the present study was twofold: to evaluate the racial differences in inflammatory and vascular responses to a HFM and to evaluate the potential impact of SDH factors on these relationships. Five black individuals (5 males, 21.2 ± 1.5 yrs) and 14 white individuals (7 males/7 females, 25 ± 4.1 yrs) completed the study. White individuals were significantly older than black individuals, but were similar in fitness status (VO2peak; 43.4 ± 10.8 ml/kg/min vs. 40.5 ± 5.9 ml/kg/min) and BMI (22.6 ± 2.9 kg/m2 vs. 23.5 ± 3.3 kg/m2). Black and white individuals exhibited similar vascular function, arterial stiffness, wave reflection, and hemodynamic variables (BP, HR) at baseline and following the HFM. Black individuals had a significantly lower total SDH score compared to white individuals, indicating lower SDH across seven domains assessed in the SDH questionnaire. However, SDH was not associated with any of the vascular measurements at baseline or following the HFM. Inflammation was not detected at baseline and following the HFM, as measured by a multiplex immunoassay. Therefore young, healthy black and white individuals maintain vascular function following a HFM, regardless of SDH status.
- ItemWrestling With the Angels: Synthesizing Assemblage Theory and Conjunctural Analysis In Examining the Korean Sport Context(2022) Yang , Junbin; Andrews, David; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Given the increase of ambiguities and uncertainties in contemporary society in general—and in sport and physical culture in particular—it is essential to explore diversified elements simultaneously rather than fixate on only a single factor (Anderson, 2014; Horton, 2020; Law et al., 2014; Ryan, 2021). Accordingly, this thesis introduces Manuel DeLanda’s (2006a, 2006b, 2011, 2016) “Deleuzian-inspired” (Andrews, 2021b, p. 72) assemblage theory as a novel approach to understanding our complex society and its continuous transformations as “assemblages of assemblages” (DeLanda, 2016, p. 3). More importantly, just as DeLanda (2006, 2011, 2016) reorganized Deleuze’s notions when he suggested his own unique assemblage theory, I reconceptualize DeLanda’s assemblage theory by adopting certain vital concepts within conjunctural cultural studies, including the notions of conjuncture and articulation, to propose my own conjunctural analysis-based assemblage theory. Additionally, on a basis of my own version of assemblage theory, I then analyze three representative conjunctures that can be found within Korean history—a longstanding period of totalitarian regimes, the national economic crisis, and contemporary Korean society—in order to discern both dominant and overlooked assemblages within them as well as their endless mutations. Considering the conspicuous paucity of theoretical and conceptual discussions concerning an assemblage and assemblage theory despite the growing academic attention paid to these concepts (Dewsbury, 2011; Savage, 2020), my clarification and reinterpretation of DeLanda’s (2006, 2011, 2016) assemblage theory will make another meaningful contribution to the advancement of its theoretical and conceptual clarification. Analyzing three particular conjunctures within Korean history using assemblage theory will also ascertain the methodological and empirical potential of the concept by illuminating certain “more-than-human aspects of the socio-material world” (Müller & Schurr, 2016, p. 217) without adhering to anthropocentrism, thereby effectively bridging the scholarly gap that exists in the field of sport and physical culture, especially between the United States and South Korea (Andrews, 2019; Coakley, 2021; Tian & Wise, 2020). Ultimately, the critical engagement with and extension of DeLanda’s (2006, 2011, 2016) assemblage theory will provide a valuable opportunity to strengthen the architecture of the complex contextual relations that can critically delineate how society has been formed and how it has come into being by offering a fundamental addendum to the contextual cultural studies approach while also investigating the structure and function of contemporary sport as multifaceted assemblages (Andrews, 2019; King, 2005).
- ItemCardiac Mitochondrial Function and Exertional Tolerance in a Rat Model of Pressure-Overload Induced Heart Failure(2022) Li, Harry Zichen; Kuzmiak-Glancy, Sarah; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Heart failure (HF) is characterized by the inability of the heart to provide adequate cardiac output to meet their body’s demand for fuel and oxygen, particularly during periods of exertion. In fact, a hallmark characteristic of HF is exertional intolerance where performing activities brings about, or exacerbates, symptoms of dyspnea and/or fatigue. This exercise intolerance has been attributed to altered cardiac and skeletal muscle function. The myocardium of the heart is reliant upon cardiac mitochondria to generate sufficient ATP to fuel this highly metabolically active tissue. Therefore, reduced mitochondrial ATP production may play a role in myocardial dysfunction and contribute to reduced cardiac output in HF. Mitochondria react to intracellular signals to respond to energetic demands, and therefore, mitochondrial function is a product of both the mitochondria itself and the environment in which it resides. Intracellular Ca2+ and Na+ are of particular interest as they play a role in regulating mitochondrial function and the intracellular concentrations are elevated in ventricular myocytes in HF. Therefore, a goal of these investigations was to evaluate how altered Na+ and Ca2+ can impact the ability of cardiac mitochondria to respond to an increase in demand in mitochondria isolated from young healthy rat hearts, as well as rats with pressure-overload induced HF. A second goal of these investigations was to determine if pressure-overload induced heart failure altered exercise capacity, as well as in vivo and ex vivo skeletal muscle strength. In the first study, mitochondria were isolated from the ventricular tissue of young, healthy male rats, and oxygen consumption and mitochondrial activation by Ca2+ was assessed in the presence of elevated Na+ to mimic the cellular environment of HF. Ca2+ effectively activated mitochondrial ATP production, despite elevated Na+, suggesting that the ionic conditions of HF ventricular myocytes alone are not sufficient to disrupt mitochondrial function. In the second study, mitochondrial function was assessed under the same ionic conditions as the previous study, however, mitochondria were isolated from male rats with pressure-overload induced hypertrophy or sham-operated controls. Ca2+ was able to activate mitochondrial function regardless of Na+ concentration in both HF and sham mitochondria; however, failing mitochondria exhibited depolarized mitochondrial membrane values across these respiration rates, implicating an impaired potential for ATP production in failing ventricular mitochondria. In the third study, HF and sham male and female rats were evaluated for their exertional tolerance, and the results indicated that HF rats tolerated treadmill running and showed no deficits in grip exercise; however, solei muscle from female heart failure rats exhibited diminished contractile capacity, suggesting female skeletal muscle may respond differently than male skeletal muscle to heart failure. These findings indicate that failing mitochondria may be intrinsically dysfunctional regardless of an altered ionic environment and that there may be sexual dimorphism in the skeletal muscle function and its role in exercise intolerance in HF.
- ItemCONCENTRATION- AND TIME-DEPENDENT EFFECTS OF PROGESTERONE ON ENDOTHELIAL CELLS(2022) Kim, Katherine In-Wha; Prior, Steven J; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)The termination of endogenous sex hormone release is thought to account for increases in cardiovascular disease (CVD) incidence in postmenopausal women. Thus, hormone replacement therapy may be a preventive measure against cardiovascular disease. To date, most research has been focused on estrogen treatment, but the effects of progesterone, a vasoactive hormone with effects on the endothelium, have received less attention. Two progesterone receptor subtypes, nuclear and membrane, are known to enact the effects of progesterone in endothelial cells which mediate the release of nitric oxide (NO). There is also some evidence that the two subtypes function in a coordinated manner. The aims of this thesis study are to assess the effects of different concentrations of progesterone on endothelial cells and isolate the actions of the progesterone receptor subtypes. Outcomes of this study include migration and proliferation assays to assess endothelial cell function and Western blotting to quantify endothelial nitric oxide synthase expression and phosphorylation. Progesterone and the membrane progesterone receptor agonist were found to inhibit migration and proliferation of human umbilical vein endothelial cells (HUVECs), while progesterone alone or in combination with the membrane progesterone receptor agonist increased endothelial nitric oxide synthase (eNOS) phosphorylation in HUVECs after 24 hours of incubation. While increased eNOS phosphorylation is thought to be beneficial to HUVEC function, other factors released in the presence of progesterone or progesterone receptor agonists may be scavenging bioavailable NO, thus reducing the angiogenic potential of HUVECs.
- ItemProtection for whom? A critical examination into the governance of women athletes through policies(2022) Posbergh, Anna; Jette, Shannon L; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Women’s sport remains a contested realm that frequently features standards and regulations implying women are “lesser than,” “different from,” or “derivative of” men (Cahn, 2015, p. 222). As such, a range of protective policies have been introduced as techniques to ensure the safety and health of women, defend “fair competition” in women’s sport, and/or prevent women from violating social and medical boundaries that identify them as women. However, because protective policies rely on divergent rationales in their creation and justification, they elicit different impacts for individuals who are categorized (or wish to be categorized) as women. Previous scholarship has analyzed the underlying issues of science, race, gender, and nationality in individual protective policies and indicated the potential for specific policies (i.e., female eligibility policies) to elicit dangerous health, social, and mental consequences on black and brown women from the Global South. However, there a paucity of research that investigates protective policies as a broad category to understand their similarities, differences, and nuances. To fill this gap, I examine multiple protective policies to conduct a critical, qualitative inquiry into how protective policies are created in elite women’s sports. I focus on how such policies regulate women’s bodies and how different versions of “woman” are constructed by interpreting and selectively drawing from myriad forms of evidence to determine who is protected (and who is excluded), how “protection” is understood, what evidence is mobilized, and how protective policy consequences are justified.I investigate three policies as case studies: the International Olympic Committee’s (IOC) 2014 consensus statement on relative energy deficiency in sport (RED-S), World Athletics’ 2019 policy on female eligibility, and World Athletics’ 2019 policy on transgender eligibility. These three policies are selected for analysis because they reflect the range of science-supported protective policies. While all seek to protect women, each adopts a different stance on the importance of sex differences, in the process demonstrating the social construction of “sex” and malleability of scientific evidence. Guided by feminist, critical race, and Foucauldian-inspired governmentality studies approaches, I center the relevant discourses, knowledges, and power relations within policy rationales to better understand how protective policies regulate (women’s) bodies and maintain social norms. Each case study analysis consists of two data sets: the actual policy texts and nine semi-structured interviews with policy authors, scientists, and other relevant administrators involved in the creation, drafting, and implementation of the three policies. I analyze the data through thematic analysis followed by Foucauldian discourse analysis, informed by a governmentality studies perspective. Using this two-step analytic framework, I first determine what was said in document texts and by participants, followed by a deeper level of analysis and contextualization of how dominant discourses, knowledges, and power relations were created and mobilized to protect (some) women athletes. My findings are organized into four empirical chapters. In the first empirical chapter, I examine the document texts to provide a broad examination into the contexts surrounding their creation, as well as the unproblematized logics that inform their dominant discourses, ways of knowing, and power hierarchies. Based on my analysis, I bring to light the implications of the logics underpinning the documents, including the use of elite medical discourses, the construction of “suspicious” athletes, biologizations of race and gender, and individual diagnoses that lack attention to broader social, political, and cultural dimensions. In the second empirical chapter, I focus on the interviews, or “expert knowledge,” with those involved with researching, drafting, and implementing the three case studies to understand how they draw from (certain) forms of evidence, interpret and/or circulate dominant discourses and knowledges, and navigate the (often) contentious process of creating protective policies (see Wells, 2020). In the third and fourth empirical chapters, I examine both sets of data (policy and interview). In the first of these two empirical chapters, I provide an overview of the “start-to-finish” process behind creating and implementing protective policies and investigate the “tensions” that emerge at each step in the process: from explaining why protective policies exist, to finding or constructing appropriate forms of evidence, to determining the necessity of a separate women’s category, to methods of governing. In the latter empirical chapter, I more closely parse through these “tensions” behind and within the rationales and strategies of protective policies to reveal the complexity reality of such documents, particularly with consideration to (protected) participation, (controlled) unfairness, and (felt) policy implementation. This dissertation is significant as it elucidates how, if, and when women’s rights and bodies are protected through policies. As sport shapes and is shaped by society, this research illuminates on a societal scale how science and policy shape dominant ways of knowing, particularly regarding gender, sex, race, and human rights. Especially in a time when legal protections of women’s autonomy, bodies, and rights are in question, this project provides insight into how protective policies enact a range of measures to safeguard (some) women’s bodies through regulation, discipline, or even exclusion. By investigating how sociocultural and scientific knowledges intersect to determine who qualifies as “woman,” who is considered in need of “protection,” and how protection is implemented, the findings from this dissertation will hopefully inform organizational and administrative efforts to create more equitable, compassionate, and inclusive policies, both in sport and society.