Kinesiology Theses and Dissertations

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    A Healthy Relationship? The Entanglement of State, Corporate, and Labor Interests in Gender-based Violence Sport Policies
    (2023) Drafts-Johnson, Lilah; Jette, Shannon; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Gender-based violence (GBV) within professional sports made headlines in 2014 following the Ray Rice domestic violence incident, prompting a Congressional hearing with the four major men’s sports leagues in the United States. This hearing resulted in the implementation of several sport industry-wide policies addressing off-field conduct for players and employees, including ones specifically focused on interpersonal relationships. Despite the cultural prominence of corporate sport entities such as the National Football League, National Basketball Association, and Major League Baseball, in addition to the fervor for institutional accountability in the wake of the #MeToo movement, there has been limited academic scholarship examining the scope and efficacy of these policies (see Brown, 2016; Augelli & Kuennen, 2018) Drawing upon the findings of a thematic analysis of Senate Hearing 113-725: Addressing Domestic Violence in Professional Sports, this thesis utilized a governmentality analytic to critically analyze the motivations, assumptions, and tensions which underpinned the institutionalization of GBV policies in corporate sport. The findings demonstrate that while the parties present at the hearing problematized sport culture at large as a producer of GBV, their remarks characterized professional male athletes as perpetrators, reifying the idea of the “violent (Black) male athlete” and violence as an inherent trait in professional sport more generally. Instead of critically interrogating the structure of professional sport, legislators instead focused on expanding the governing capacity of sport leagues, and effectively the state, to discipline and punish perpetrators of GBV by encouraging the implementation of new extra-legal policies. I argue that this hearing reinforced the neoliberal entanglement of state, corporate, and non-profit actors in the movement to reduce GBV in society, strengthening the dependency that the state has on corporate social responsibility to solve leading public health issues, and compelling GBV advocates, activists, and scholars to engage with corporations in order to receive critical funding and legitimacy in their work. Meanwhile, suggested legislation to improve economic and workplace conditions for survivors was ignored as labor issues were positioned as oppositional to GBV accountability efforts. Through articulation and radical contextualism, this thesis sheds new insight into the origins and methods of corporate GBV policies in sport as well as the intricacies of contemporary neoliberal governance, and ultimately argues that the state response to GBV must shift from one of punishment and surveillance to one of preventative care through improved economic and labor conditions for all workers.
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    (2023) Burnett, Jenna K; Shim, Jae Kun; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Individuals with transfemoral amputation commonly develop chronic health problems due to decreased physical activity as a result of the missing musculature and tissue on the amputated side, and the poor imitation of the intact limb provided by the prosthesis. In addition, the indirect and semi-rigid connection of the socket to the body may increase interlimb asymmetries, as well as lead to pain and discomfort on the residual limb. Recent innovations have introduced a bone-anchored or osseointegrated (OI) implant which connects the prosthesis to the skeleton, and removes most of the socket related pain and discomfort complaints, as well as providing a rigid connection which may reduce the interlimb asymmetries. However, the direct bone and prosthesis connection may also introduce longitudinal bone health concerns due to the repetitive loads during walking. This dissertation investigated the effect of walking speed on the loads placed on the lower limbs of 11 individuals who use an OI prosthesis at 3 different anatomical levels, including the whole limb through interlimb ground reaction force, the joints through interlimb joint kinematics and kinetics, and finally the residual limb bone through implant input forces, finite element analysis of bone strain, and the probability of bone injury with a simulated lifetime of use.In study 1, the interlimb ground reaction force asymmetries were found to be moderate to large at all walking speeds, and to have a general increase as individuals walked faster, indicating there is an intact limb reliance strategy which may be used to compensate for the limitations of the amputated limb. Similarly, in study 2, the interlimb joint kinematics and kinetics were found to have moderate to large asymmetries at each joint level, with a general increase in asymmetry at faster walking, with this increase largely due to limitations within the prothesis. In study 3, the abutment force decreased in magnitude with walking speed, but the peak strain on the bone, and the probability of injury was greater for the preferred speed and fast speed walking when compared to slow speed walking. However, the overall probability of injury was low for all speeds, indicating the ability of the bone to repair and adapt with sustained loading likely provides effective protection over a lifetime of simulated OI prothesis use. The findings of this dissertation suggest that the more rigid connection afforded by the OI implant cannot fully remove the interlimb asymmetries which occur as a result of the poor imitation of the intact limb provided by the prosthesis and prosthesis components, but that there is minimal risk to the bone due to a lifetime of sustained walking with an OI prosthesis as a result the inherent ability of the bone to repair and adapt to variable loads over time. Therefore, while an OI prosthesis may not fully mitigate the interlimb asymmetries which occur as a result of the prosthesis limitations, individuals who use an OI prosthesis may feel confident that there is minimal longitudinal risk to the bone as a result of walking over their lifetime.
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    (2023) Bell, Elizabeth M; Miller, Ross H; Shim, Jae K; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Clinical evidence suggests that experiencing pregnancy increases a woman’s risk of knee osteoarthritis, a painful and mobility limiting disease that results from cartilage deterioration. While understanding the underlying causes and the association with pregnancy is complex, the mechanical load on cartilage during walking appears to be important to the initiation and progression of the disease, especially if walking mechanics are abnormal. Pregnancy involves various changes in mechanical factors like mass, center of mass, and joint laxity which are known to progressively change walking mechanics throughout gestation. However, it is unknown if mechanical changes associated with pregnancy, which may be substantial in magnitude but may be limited in duration, can explain the osteoarthritis risk since osteoarthritis is diagnosed later in life. Given that women typically experience pregnancy early in their lifetime and will need healthy knees for decades after they become mothers, this research aimed to model the mechanical consequences of pregnancy on knee joint loading and knee joint health over the lifetime. Specifically, this dissertation sought to (i) determine how pregnancy influences variables like resultant knee joint kinetics, which more directly indicate the load on cartilage over a range of walking speeds (ii) estimate the impact of pregnancy on internal knee joint forces and tibiofemoral cartilage load during walking and (iii) evaluate the isolated effect of altered loading experienced during pregnancy on cartilage degeneration and the risk of knee osteoarthritis throughout a woman's lifetime. Results suggest that (i) 3D knee joint moments over a range of walking speeds are greater in pregnant vs. non-pregnant individuals and knee adduction moments are altered as pregnant women walk faster. Similarly, pregnant women experience greater total knee joint loading and greater medial knee joint loading which results in additional and altered peak strain on knee cartilage with greater walking speed. Finally, the elevated and altered compressive load experienced over one or more pregnancies resulted in a greater cartilage failure probability, with differential effects when women experience multiple pregnancies later in their lifetime. These findings support the notion that the mechanical factors associated with pregnancy significantly alter knee joint loading and mechanical changes may, in part, contribute to the known association between pregnancy and risk for knee osteoarthritis risk over a woman’s lifetime. Further, present-day American mothers who are conceiving at later stages of life compared to previous generations may be more susceptible to knee osteoarthritis. Future investigations are needed to explore effects postpartum and for populations beyond healthy, active pregnant women. Further research could also investigate if biomechanical adjustments could be used as potential interventions to lessen knee joint loading and potentially decrease the risk of knee osteoarthritis among this population.
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    (2023) Ginsberg, Andrew A; Hatfield, Bradley D; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    The dissertation describes a programmatic research effort involving a series of studies (study one, two, three) to address the phenomenon of cognitive strategies facilitating and contributing to enhanced motor performance. Cognitive strategies consist of various mental approaches used before or during the execution of a motor task to improve performance. Psyching, one of the common strategies, typically involves a combination of elements intended to modify arousal and attentional focus to enhance performance. Prior findings within the sport psychology literature have revealed positive effects of psyching on performance, however, the underlying mechanisms of effect are not well understood. To further understand changes in musculoskeletal performance as a result of psyching, the present research used a multidimensional approach (psychological + psychophysiological + kinetic) by employing the measures of electroencephalography (EEG) - cortical activity, electromyography (EMG) - muscle activity, and isokinetic dynamometry - peak torque during maximal exertion to achieve peak torque of a dynamic knee-extension skeletal muscle action. In each of the three studies, participants performed the psychomotor task under three different preparatory strategies, a task-related attentional focus strategy and for comparative purposes mental arithmetic (MA) and reading comprehension (RC) strategies serving as attentional distractions. Participants were characterized as untrained. The results of Study One provide evidence that task-related attentional focus, compared to distracting attentional strategies, is associated with increased force production. The EEG results of study two provide further evidence suggesting that during preparation for movement, the task-related attentional focus distributed neural resources toward task-related regions and away from task-irrelevant regions. Such a phenomena is consistent with the notion of the alpha (i.e., inhibitory) gating as described by Jensen and Mazaheri (2010). A novel contribution of study two was the experimental manipulation of cognitive strategies (RC, MA, PSY) in order to isolate on the element of task-related attentional focus. The primary focus of the program of research was Study Three. Participants were characterized as expert (highly strength trained athletes) with a training status identified as advanced. An additional comparative “resting” condition was implemented to engage the degree of cortical arousal during the three kicking conditions. Individualized alpha power (IAF) as an index as inhibition was subjected to a 4 Strategy (EO, MA, RC, PSY) x 6 ROI (central, frontal, left temporal, right temporal, parietal, occipital) x 4 Time (-20 to -15 s, -15 to -10 s, -10 to -5 s, and -5 to 0 s relative to knee extension initiation) repeated-measures ANOVA. Integrated EMG (iEMG) was subjected to a 3 Strategy (MA, RC, PSY) x 3 Muscle (rectus femoris (RF), vastus medialis (VM) and vastus lateralis (VL)) x 2 Time (-1 to 0 s, 0 to +1 s, respectively corresponding to “pre” and “post” initiation of the knee extension) repeated-measures ANOVA. Peak Torque was subjected to a 4 Strategy (BL, MA, RC, PSY) one-way repeated-measure ANOVA. The BL strategy consisted of maximal exertion during an orientation session in the absence of attentional manipulation. Study three replicated and extended the results of study one and study two suggesting that the use of task-related attentional focus leads to better performance, via the influence of brain and muscle activity. More specifically, enhanced motor performance was achieved via the task-focus cognitive strategy through heightened localized brain activity. In the evaluation of elite athletes, it appears that motor cortex activation is robustly elevated compared to rest across all three strategies in the motor region. Accompanied by heightened inhibition in non-motor regions as a results of the task-related focus. EMG revealed that task-related attentional focus was associated with an increase of neuromuscular activation of the quadriceps muscles. Although beyond the scope of this research, a cascade of events provides a model for explaining the influence of cognitive strategies on maximal skeletal muscle performance. Namely, the focused brain dynamics associated with the task-related focus leads to elevated motor unit recruitment which translates to heightened musculoskeletal performance (peak torque). The findings of this research program extend the neural efficiency model of human performance and support the gating-by-inhibition phenomenon as a central factor. That is, the attentional focus translated to heightened localization of motor activity in the brain resulting in elevated performance.
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    Effects of a High-Fat Meal on the Inflammatory Phenotype and Function of Monocytes
    (2023) Shoemaker, Madison; Prior, Steven J; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Cardiovascular disease (CVD) remains the leading cause of mortality throughout the world. Atherosclerosis, the buildup of plaque within the arteries, is the main cause of CVD. An early and essential step in the pathogenesis of atherosclerosis is the formation of foam cells, derived from lipid-laden macrophages that become trapped within the tunica intima. Macrophages, through the scavenger receptor CD36, take up a modified form of cholesterol, oxidized low-density lipoprotein (oxLDL), at a rapid rate, which causes them to become lipid-laden and trapped. Chronic inflammation causes endothelial damage and dysfunction, increasing the permeability to circulating LDL, which becomes oxidized within the arteries. Due to the difficulty of studying the macrophages within atherosclerotic plaque, recent research has shifted to the study of their biological precursor: monocytes. A high-fat meal (HFM), an experimental model used to assess postprandial inflammation, was used to assess the role of this HFM-induced inflammation on the likelihood of monocytes to eventually become foam cells. We also included an additional oxLDL ex vivo treatment to gain further insight into the potential “priming” effect of a single HFM. While there was a significant increase in the inflammatory cytokine tumor necrosis factor alpha (TNF-a) in response to the HFM, there were no significant changes in monocyte oxLDL uptake or cell surface marker expression. Future studies may want to examine the inflammatory role that higher concentrations of oxLDL may have or examine other postprandial markers of inflammation in an older or at-risk population.
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    Associations between Classical Music, Physical Activity and Symptoms of Depression in Older Adults during the COVID-19 Pandemic
    (2023) Arnold-Nedimala, Naomi A; Smith, J Carson; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Background: The initial lockdown in March 2020 due to COVID-19 rattled the residents of North America as normalcy came to a standstill, freedom was stripped away, and people were forced to adapt to new restrictions and regulations, simply to survive. The elderly population was greatly affected by the lockdown as it prohibited those living in assisted living facilities to physically interact with family and friends highlighting the need to identify protective behaviors against mental health and depression. The neurological benefits of listening to classical music is an emerging area of research. A few studies suggest the positive outcomes of listening to classical music in reducing symptoms of depression. Additionally, while the cardiovascular benefits of exercise are well known, the impact of exercise on affect continues to be an emerging area of research. Purpose: The purpose of this study is to understand the efficacy of listening to classical music in attenuating symptoms of depression in older adults (50 – 90+) utilizing data collected from 3 separate time points during the COVID-19 pandemic, and to determine if physical activity is associated with providing additional benefit to lowering symptoms of depression Methods: A survey including the Geriatric Depression Scale (GDS), the Physical Activity Scale for the Elderly (PASE), and questions about listening to music (classical, Broadway, Christian music), and the frequency of listening to music was generated and distributed to people living in the United States and Canada immediately following the initial COVID-19 lockdown in April 2020. Informed consent was obtained prior to completing the survey, and participants who were interested in receiving a follow-up survey were asked to provide their email addresses. The follow-up surveys were generated 4-months (August 2020) and one year (April 2021) after the initial survey. Results: At the initial onset of the COVID-19 lockdown in April 2020, significant associations were observed between classical music listening (CML) and lower symptoms of depression, physical activity (PA) and lower symptoms of depression, music listening frequency, and lower symptoms of depression. In August 2020 and April 2021, significant associations were found between physical activity and lower symptoms of depression. However, no associations were observed between classical music listening and lower symptoms of depression, and music listening frequency and lower symptoms Additionally, significant associations were observed between age and lower symptoms of depression, sex, and lower symptoms of depression at all three time points. Conclusion: The results from our study suggest that there is an association between classical music listening and symptoms of depression, physical activity and symptoms of depression, music listening frequency and symptoms of depression in older adults (50+) during the early stages of the COVID-19 pandemic (April 2020). Additionally, the association between physical activity and symptoms of depression was maintained throughout the first year of the pandemic as supported by the data collected in August 2020 (4 months) and April 2021 (12-months).
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    The Effect of Variability of Practice on the Performance of the Layout Squat Vault
    (1989) Khayat-Mofid, Fariborz; Church, Kenneth; Physical Education; Digital Repository at the University of Maryland; University of Maryland (College Park, MD)
    This study focuses on Schema Theory which maintains that the practice of motor skiIIs store a set of general memory of movements. This memory guides the performance of demands specifically made from the environment as well as the objective or goal of the performer. The layout squat vault was selected as the motor task to be studied, since it is a basic vault of gymnastics. The most important factor of a good vault is the angle of the hips and shoulders to the horse at the moment of contact by the hands. It was hypothesized that if Schema Theory is applicable, subjects who practice vaulting at varying heights will achieve a better angle of contact with the horse than wiII subjects who practice when the vault remains at a constant height. The investigation examined the effects of varied heights of the vault during practice to the transfer of new tasks. The study specifically studied the Schema Theory in the performance of the layout squat vault at the time of contact with the horse. Subjects were 38 females, aged 9 to 11 years, who were randomly assigned to two groups. One group practiced at a single height; the other group practiced vaulting at varying heights for 36 practice trails over a period of two days. When this was completed, three consecutive vaults were assigned at a new height for each subject of both groups. At the same time, the subjects were video-taped. Using the tape, four qualified judges scored each of the subjects. The highest and lowest scores for each vault were eliminated. The two remaining scores were averaged to produce the final score. The Students t test for the difference of means was used to determine the differences between the groups. The results showed that the high variability practice group was superior to the non variability practice group. It was concluded that Schema Theory could be applied to closed skills such as vaulting in gymnastics and that there was support for the Schema Theory.
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    (2023) Evans, William Stuart; Prior, Steven J; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Chronic inflammation is a hallmark of cardiovascular disease; however, there is a lack of understanding of how systemic inflammation affects the peripheral skeletal muscle to potentially hasten frailty and functional declines in patients. The overarching objective of this dissertation was to determine whether this systemic inflammation is accompanied by macrophage infiltration of skeletal muscle and reductions in skeletal muscle capillarization and fiber size. Using animal models of a) heart failure (HF) induced by transverse aortic constriction (TAC), and b) skeletal muscle ischemia, this work illuminates changes that occur in skeletal muscle with cardiovascular disease-related inflammation. The first study demonstrated that pressure overload resulted in cardiac hypertrophy in male rats consistent with heart failure with preserved ejection fraction (HFpEF), while females did not show cardiac hypertrophy or HF. The second study demonstrated sex-specific differences in skeletal muscle, with TAC male rats exhibiting smaller fiber sizes and greater capillarization, and female TAC rats exhibiting lower capillarization than Sham counterparts. This study then investigated skeletal muscle macrophages to determine whether they might underly or contribute to these differences. There were fewer macrophages in the skeletal muscle of male TAC rats than male Sham rats, and macrophage conditioned medium from TAC rats produced less-developed capillary networks in an ex vivo, experimental assay. Finally, the third study investigated whether an acute bout of systemic inflammation, in the absence of HF, could alter the infiltration of macrophages, or skeletal muscle fiber size or capillarization. Hindlimb ischemia was used to induce acute, systemic inflammation that peaked after 1 day. This systemic inflammation increased the infiltration of macrophages into remote, non-ischemic skeletal muscle by day 7; however, muscle structure was preserved over this short time course. This dissertation demonstrates that cardiovascular disease-associated inflammation is linked with tissue-level changes in macrophages in a sex-specific manner. These changes accompany and may, over time, contribute to skeletal muscle fiber atrophy and changes in capillarization in cardiovascular disease patients.
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    (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.
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    Wrestling 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).
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    Cardiac 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.
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    (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.
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    Protection 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.
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    America's Sweethearts? A Feminist Discourse Analysis of Dallas Cowboys Cheerleaders: Making The Team
    (2022) Nowosatka, Lauren Riley; Jette, Shannon L.; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    The “often imitated, never equaled” Dallas Cowboys Cheerleaders (DCCs) are self-proclaimed as “the premier cheerleading squad in the world,” universally setting the stage (field) for professional cheerleading. In 2006, “America’s Sweethearts” launched a hit reality television (TV) show, Dallas Cowboys Cheerleaders: Making The Team (DCCs: MTT), where the squad director positions the organization as empowering women in the opening the series’ 13th season. Taking this seemingly contradictory statement—made during the #MeToo moment of 2018—as a department point, this thesis examines the constructions of femininity and empowerment on offer in season 13 of DCCs: MTT. A textual analysis adopted from Johnson et al.’s (2004) reading for dominance methodology, with a theoretical foundation in feminist discourse analysis and intersectionality, was used to examine season 13 of DCCs: MTT, answering the following questions: 1. What versions of femininity are on offer to viewers of Dallas Cowboys Cheerleaders: Making The Team? How do they intersect with race, sexuality, class, ability, etc.? 2. How is empowerment constructed through Dallas Cowboys Cheerleaders: Making The Team? Findings suggest that performances of femininity are aligned with emphasized femininity and ambassadorship, offering a homogenous image to viewers that idealizes and reinforces hegemonic beauty standards, the thin-ideal, and the objectification of women, paired with displays of emotional expressions, “intelligence,” and poise that subjectively position the cheerleaders within the larger patriarchal, late-capitalist Dallas Cowboys and NFL structures. Supposedly empowering to the cheerleaders, the discursive practices, enforced performativities, and productional strategies displayed on season 13 of DCCs: MTT, frames the institution as faux-empowering, endorsing empowerment as the product of making “correct” individual choices. Consequently, cheerleaders and viewers who do not make these decisions are rendered disempowered and made to feel shameful, contradicting the spirited nature of the sport. This thesis seeks to fill the gap created by the lack of critical, sociological discussions of professional cheerleading as a spectacle of late-capitalist, uber sport, permeated through popular culture and which analyzes professional cheerleading through the site of reality TV.
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    (2021) Mascone, Sara Elizabeth; Ranadive, Sushant M; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Black individuals are predisposed to an earlier onset and higher prevalence of cardiovascular disease, such as hypertension. Hypertension may be caused by inflammation and heightened levels of reactive oxygen species (ROS). At rest, Black and White individuals exhibit divergent in vivo and in vitro inflammation, ROS production, and ROS clearance. This study investigated racial differences in ROS production and ROS clearance following induced inflammation in human plasma and HUVECs from Black (B HUVECs) and White (W HUVECs) individuals. W HUVECs, but not B HUVECs, exhibited significantly greater ROS production with increased exposure to TNF-α. Further, W HUVECs alone experienced a significant increase in SOD activity with increased time that was abolished with TNF-α. The HUVEC data were also analyzed for sex differences. HUVECs from females exhibited significantly lower ROS production than HUVECS from males basally and following TNF-α treatment. Female HUVECs alone exhibited significantly greater SOD activity with increased exposure to TNF-α. The findings suggest a ‘priming’ for lower ROS production via greater total antioxidant status (from non-SOD antioxidants) in B HUVECs. Further, male HUVECs may be predisposed to a pro-inflammatory state due to higher androgen exposure in fetal umbilical cord blood.
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    (2021) Lu, Calvin; Hatfield, Bradley D; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Research in performance optimization aims to improve cognitive-motor performance under arduous conditions. From a kinesiology perspective, effectiveness in performance optimization can be quantified through the neurophysiological economy of goal-directed motor behavior. Derived from the psychomotor efficiency hypothesis, the cognitive-affective-motor (CAM) model discusses the brain's complex intersections of cognitive-motor and cognitive-affective processes. The CAM model subscribes to the principle that superior performance is achieved by minimizing nonessential motoric processes, such as mental stress management. When stress response becomes unmanageable, there will be an elevation in nonessential motoric processes and negatively impact motor preparation. The resulting disfluency within the central nervous system will ultimately manifest in the motor and autonomic sections of the peripheral nervous system. To combat the disruptive effects of mental stress, employing autonomic regulation techniques such as Vagus nerve neuromodulation can remedy the inefficiencies of the nervous systems and promote an adaptive state for performance. This dissertation aimed to assess the CAM model empirically by investigating the integrative model of the cortical, autonomic, and motor nervous systems during a precision motor task (i.e., dart-throwing). A thorough examination was conducted on preserving the nervous system’s efficiency and positive impacts on the quality of motor performance through Vagus nerve neuromodulations. Specifically, the study focused on varying levels of mental stress to determine inoculation capabilities. Twenty-three participants were enrolled in a repeated-measures within-subjects design. Neurophysiological measures of nervous system activity were captured before motor execution to determine the amalgamated influence of Vagus nerve neuromodulation and mental stress. The observed results revealed an elevation in psychomotor efficiency through the Vagus nerve neuromodulations. Participants exhibited improved performance, as seen through a reduction of accuracy variability. This was accompanied by nervous system alterations of increased left temporal alpha power, reduced motor unit engagements, and reduced mental workload during the preparation of motor execution. In summary, the observed effects of Vagus nerve neuromodulation techniques successfully promoted nervous system efficiency and an adaptive state for goal-directed motor behavior. The dissertation outcomes provide evidence on the benefits of ergonomic aids such as Vagus nerve neuromodulation on facilitating an adaptive nervous system to enhance cognitive-motor performance.
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    (2021) Won, Junyeon; Smith, J. Carson; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    BACKGROUND: Age-related cholinergic dysfunction within the basal forebrain (BF) is associated with cognitive decline and Alzheimer’s disease (AD) in older adults. Accumulating evidence suggests that higher cardiorespiratory fitness (CRF) is linked to neuroprotective effects. However, we have yet to understand the associations between CRF, BF cholinergic function, and cognitive function in older adults. In humans, resting state functional connectivity (rsFC) using functional MRI (fMRI) is useful to characterize the functional aspect of the BF cholinergic connectivity. PURPOSE: 1) To investigate the relationships between CRF-BF rsFC, CRF-cognitive performance, and BF rsFC-cognitive performance in older adults; 2) To investigate the moderating effects of CRF in the relationship between BF rsFC and cognitive function; 3) To investigate the possibility of BF rsFC as a neurophysiological mechanism underpinning the association between CRF and cognitive function in older adults. METHODS: We utilized a publicly available dataset from the Nathan Kline Institute Rockland Sample in which CRF, cognitive test scores (e.g., Rey Auditory Verbal Learning Test, Delis-Kaplan color-word Interference test, and D Delis-Kaplan trail making test), and fMRI data are available in a large sample of older adults. Resting-state fMRI were preprocessed using a rigorous method and valid image processing software. Linear regression models were used to assess the associations between CRF, BF rsFC, and cognitive performance in Specific Aim 1. Sex-dependent differences in the BF rsFC were also investigated as a post-hoc analysis. The interaction between CRF and BF rsFC on cognitive performance was tested using linear regression and analysis of covariance (ANCOVA) for Specific Aim 2. Mediation analysis was administered to examine the possible mediating role of BF rsFC in the relationship between CRF and cognitive function (Specific Aim 3). RESULTS: There was an association between higher CRF and greater NBM rsFC in older adults. There were significant correlations between CRF, CRF-related NBM rsFC, and trail making test performance only in women. Importantly, higher CRF was associated with better Trail Making performance through greater NBM rsFC in females. Lastly, higher CRF was associated with a greater positive association between NBM rsFC and Color-Word Interference performance in older women. CONCLUSION: Higher CRF is associated with greater NBM rsFC in older adults. The association between higher CRF and better executive function performance, however, was evident only in females. Our results further provide evidence that the NBM rsFC may be an underlying neural mechanism in the relationship between CRF and executive function specifically in older women. Hence, sex differences may exist within the CRF-related neuroprotective effects on the NBM functional network and executive function.
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    Cerebral Cortical Networking for Mental Workload Assessment during Practice of a Novel Motor Skill
    (2021) Galway, William; Gentili, Rodolphe; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Although many studies have investigated mental workload during performance, its examination through functional connectivity during motor practice/learning is limited thus requiring further investigations. Therefore, this work aims to examine performance and functional connectivity dynamics underlying mental workload during motor practice by combining a robust computational method to derive connectivity and a human-machine interface which mitigates the use of participants’ prior motor experience since it can bias the acquisition process. Participants practiced reaching with a robotic arm through a head-controlled interface while kinematics and EEG were collected. The robotic end-effector kinematics quantified the performance and the Weighted Phase Lag Index indexed the connectivity during movement planning. Although performance improved during practice, the functional connectivity dynamics suggest that the recruitment of cognitive- motor resources decreased to a certain extent but that further training is likely needed to attenuate the mental workload. The work can also inform the training and design of assistive devices.
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    Weighing the Body: Olympic Weightlifters' Negotiations of Weight Class & Body Ideals
    (2021) Nelson, Monica; Jette, Shannon; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    Despite the demanding physical requirements of the sports in which they compete, the bodily practices of competitive athletes are informed and constrained by the athletic and dominant discourses that they are surrounded by. Gendered discourses of the ideal body may induce female athletes to avoid development of “masculine” muscle (Krane et al., 2004); dominant healthist discourses that demonize body fat can contribute to physiological impairments among athletes participating in lean-sport cultures (Ackerman et al., 2020). Through feminist poststructuralist analysis of semi-structured, in-depth interviews with eight male and eight female competitive Olympic Weightlifters, this thesis examines how male and female strength athletes negotiate multiple discourses about acceptable and “athletically-functional” bodies when choosing their weight classes. This study also observes how athletes manipulate (and are manipulated by) their bodies in order to accommodate and resist dominant discourses, offering a demonstration of the social and biological construction of the athletic body.
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    Will there be a season? The impact of COVID-19 on anxiety within NCAA student athletes compared to non-athlete university students
    (2021) Peterman, Kirsten; Smith, J. Carson; Kinesiology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    COVID-19 triggered psychological stress. College aged students and student athletes are among those vulnerable to mental health. The purpose of this study was to compare anxiety and potential moderators between student athletes and non-athlete students during the pandemic. Data were retrieved using survey methodology via Qualtrics. Student/athlete status was not related to anxiety (p=0.503). CF (p=<0.001), FFC (p=<0.001), and TFC (p=0.016) were associated with anxiety. There were no differences in coping between groups, however, greater TFC was related to greater anxiety in non-athlete students (p=< 0.001). Communication from AD’s (p=0.010) and teammates (p=0.033), as well as access to resources (p=0.036) were associated with anxiety in student athletes. Communication from coaches did not impact anxiety (p=0.545). Overall, anxiety during the pandemic was high. FFC may act as a protective factor, whereas TFC may worsen anxiety. Social support, access, and communication are crucial in times of uncertainty.