Kinesiology Research Works
Permanent URI for this collectionhttp://hdl.handle.net/1903/1635
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Item Arterial function in response to a 50 km ultramarathon in recreational athletes(Wiley, 2024-06-11) Ranadive, Sushant M.; Weiner, Cynthia M.; Eagan, Lauren E.; Addison, Odessa; Landers-Ramos, Rian Q.; Prior, Steven J.This study was performed to determine whether prolonged endurance running results in acute endothelial dysfunction and wave-reflection, as endothelial dysfunction and arterial stiffness are cardiovascular risk factors. Vascular function (conduit artery/macrovascular and resistance artery/microvascular) was assessed in 11 experienced runners (8 males, 3 females) before, during and after a 50 km ultramarathon. Blood pressure (BP), heart rate (HR), wave reflection, augmentation index (AIx) and AIx corrected for HR (AIx75) were taken at all time points—Baseline (BL), following 10, 20, 30 and 40 km, 1 h post-completion (1HP) and 24 h post-completion (24HP). Flow-mediated dilatation (FMD) and inflammatory biomarkers were examined at BL, 1HP and 24HP. Reactive hyperaemia area under the curve (AUC) and shear rate AUC to peak dilatation were lower (∼75%) at 1HP compared with BL (P < 0.001 for both) and reactive hyperaemia was higher at 24HP (∼27%) compared with BL (P = 0.018). Compared to BL, both mean central systolic BP and mean central diastolic BP were 7% and 10% higher, respectively, following 10 km and 6% and 9% higher, respectively, following 20 km, and then decreased by 5% and 8%, respectively, at 24HP (P < 0.05 for all). AIx (%) decreased following 20 km and following 40 km compared with BL (P < 0.05 for both) but increased following 40 km when corrected for HR (AIx75) compared with BL (P = 0.02). Forward wave amplitude significantly increased at 10 km (15%) compared with BL (P = 0.049), whereas backward wave reflection and reflected magnitude were similar at all time points. FMD and baseline diameter remained similar. These data indicate preservation of macrovascular (endothelial) function, but not microvascular function resulting from the 50 km ultramarathon.Item Acute cycling exercise and hippocampal subfield function and microstructure in healthy older adults(Wiley, 2023-08-01) Callow, Daniel D.; Kommula, Yash; Stark, Craig E.L.; Smith, J. CarsonAging is associated with deterioration in dentate gyrus (DG) and CA3, both crucial hippocampal subfields for age susceptible memory processes such as mnemonic discrimination (MD). Meanwhile, a single aerobic exercise session alters DG/CA3 function and neural activity in both rats and younger adults and can elicit short-term microstructural alterations in the hippocampus of older adults. However, our understanding of the effects of acute exercise on hippocampal subfield integrity via function and microstructure in older adults is limited. Thus, a within subject-design was employed to determine if 20-min of moderate to vigorous aerobic exercise alters bilateral hippocampal subfield function and microstructure using high-resolution functional magnetic resonance imaging (fMRI) during an MD task (n = 35) and high angular resolution multi-shell diffusion imaging (n = 31), in healthy older adults, compared to seated rest. Following the exercise condition, participants exhibited poorer MD performance, particularly when their perception of effort was higher. Exercise was also related to lower MD-related activity within the DG/CA3 but not CA1 subfield. Finally, after controlling for whole brain gray matter diffusion, exercise was associated with lower neurite density index (NDI) within the DG/CA3. However, exercise-related differences in DG/CA3 activity and NDI were not associated with differences in MD performance. Our results suggest moderate to vigorous aerobic exercise may temporarily inhibit MD performance, and suppress DG/CA3 MD-related activity and NDI, potentially through neuroinflammatory/glial processes. However, additional studies are needed to confirm whether these short-term changes in behavior and hippocampal subfield neurophysiology are beneficial and how they might relate to long-term exercise habits.Item Arterial stiffness and blood pressure are similar in naturally menstruating and oral contraceptive pill-using women during the higher hormone phases(Wiley, 2022-02-24) Eagan, Lauren E.; Chesney, Catalina A.; Mascone, Sara E.; Ranadive, Sushant M.New Findings What is the central question of this study? Are there differences in blood pressure, arterial stiffness and indices of pressure waveforms between young oral contraceptive pill-using and naturally menstruating women during lower and higher hormone phases of their cycles? What is the main finding and its importance? Blood pressure, arterial stiffness and indices of pressure waveforms are influenced similarly by exogenous and endogenous hormones. However, lower levels of exogenous hormones moderately increase blood pressure among oral contraceptive pill-using women. Elevations in blood pressure (BP) are understood as having a bidirectional relationship with stiffening of central and peripheral arteries. Arterial stiffness is mitigated by oestrogen, which aides in arterial vasorelaxation. To evaluate whether BP, stiffness, and pressure waveforms were different between young healthy naturally menstruating (non-OCP) and oral contraceptive pill (OCP)-using women, we measured brachial and aortic BPs, carotid-to-femoral pulse wave velocity, carotid β-stiffness, elastic modulus, central augmentation index and augmentation index normalized to a heart rate of 75 bpm, and forward and backward pressure waveforms in 22 women (22 (1) years, OCP: n = 12). To assess phasic differences, women were studied during the early follicular (≤5 days of menstruation onset) and early luteal (4 (2) days post-ovulation) phases of non-OCP and compared to the placebo pill (≤5 days of onset) and active pill (≤5 days of highest-dose active pill) phases of OCP. During the lower hormone phases, OCP users had significantly higher brachial systolic blood pressure (SBP) (119.3 (8.3) vs. 110.2 (8.3) mmHg, P = 0.02) and aortic SBP (104.10 (7.44) vs. 96.80 (6.39) mmHg, P = 0.03) as compared to non-OCP users; however, during the higher hormone phases, there were no differences in measures of brachial or aortic BP, arterial stiffness, or indices of BP waveforms between OCP and non-OCP users (P ≥ 0.05). In conclusion, exogenous and endogenous hormones have similar influences on BP and arterial stiffness; however, lower levels of exogenous hormones augment both central and peripheral BPs.Item Race and sex differences in ROS production and SOD activity in HUVECs(PLoS, 2023-10-04) Mascone, Sara E.; Kim, Katherine I.; Evans, William S.; Prior, Steven J.; Cook, Marc D.; Ranadive, Sushant M.Black individuals and men are predisposed to an earlier onset and higher prevalence of hypertension, compared with White individuals and women, respectively. Therefore, the influence of race and sex on reactive oxygen species (ROS) production and superoxide dismutase (SOD) activity following induced inflammation was evaluated in female and male human umbilical vein endothelial cells (HUVECs) from Black and White individuals. It was hypothesized that HUVECs from Black individuals and male HUVECs would exhibit greater ROS production and impaired SOD activity. Inflammation was induced in HUVEC cell lines (n = 4/group) using tumor necrosis factor-alpha (TNF-α, 50ng/ml). There were no between group differences in ROS production or SOD activity in HUVECs from Black and White individuals, and HUVECs from Black individuals exhibited similar SOD activity at 24hr compared with 4hr of TNF-α treatment (p>0.05). However, HUVECs from White individuals exhibited significantly greater SOD Activity (p<0.05) at 24hr as compared to 4hr in the control condition but not with TNF-α treatment (p>0.05). Female HUVECs exhibited significantly lower ROS production than male HUVECs in the control condition and following TNF-α induced inflammation (p<0.05). Only female HUVECs exhibited significant increases in SOD activity with increased exposure time to TNF-α induced inflammation (p<0.05). HUVECs from White individuals alone exhibit blunted SOD activity when comparing control and TNF-α conditions. Further, compared to female HUVECs, male HUVECs exhibit a pro-inflammatory state.Item Physical Activity and Brain Function in Older Adults at Increased Risk for Alzheimer’s Disease(MDPI, 2013-01-14) Smith, J. Carson; Nielson, Kristy A.; Woodard, John L.; Seidenberg, Michael; Rao, Stephen M.Leisure-time physical activity (PA) and exercise training are known to help maintain cognitive function in healthy older adults. However, relatively little is known about the effects of PA on cognitive function or brain function in those at increased risk for Alzheimer’s disease through the presence of the apolipoproteinE epsilon4 (APOE-ε4) allele, diagnosis of mild cognitive impairment (MCI), or the presence of metabolic disease. Here, we examine the question of whether PA and exercise interventions may differentially impact cognitive trajectory, clinical outcomes, and brain structure and function among individuals at the greatest risk for AD. The literature suggests that the protective effects of PA on risk for future dementia appear to be larger in those at increased genetic risk for AD. Exercise training is also effective at helping to promote stable cognitive function in MCI patients, and greater cardiorespiratory fitness is associated with greater brain volume in early-stage AD patients. In APOE-ε4 allele carriers compared to non-carriers, greater levels of PA may be more effective in reducing amyloid burden and are associated with greater activation of semantic memory-related neural circuits. A greater research emphasis should be placed on randomized clinical trials for exercise, with clinical, behavioral, and neuroimaging outcomes in people at increased risk for AD.Item The Influence of Family Dog Ownership and Parental Perceived Built Environment Measures on Children’s Physical Activity within the Washington, DC Area(MDPI, 2017-11-16) Roberts, Jennifer D.; Rodkey, Lindsey; Grisham, Cortney; Ray, RashawnSedentary behavior and physical inactivity are significant contributors to youth obesity in the United States. Neighborhood dog walking is an outlet for physical activity (PA). Therefore, understanding the relationship between built environment, dog ownership, and youth PA is essential. This study examined the influence of dog ownership and parental built environment perceptions on children’s PA in the Washington, D.C. area. In 2014, questionnaires were mailed to 2000 parents to assess family dog ownership; children’s outdoor dog walking or playing; and parental perceived built environment measures. Chi-square analyses examined differences in parental perceived built environment measures between children with and without family dogs. The sample included 144 children (50% female; average-age 9.7 years; 56.3% White; 23.7% African-American; 10.4% Asian-American; 29.9% owned dog). Only 13% and 5.6% of the children walked or played outdoors with the dog daily, respectively. A significantly greater proportion (p-value < 0.05) of parents who owned dogs recognized and observed some home built environment measures (e.g., traffic speed on most streets is 30 mph or less) that were PA -promoting for their children. Findings suggest that dog ownership may provide more positive parental perceptions of the neighborhood built environment, which supports children’s outdoor PA through dog walking and playing.Item Examining the Influence of a New Light Rail Line on the Health of a Demographically Diverse and Understudied Population within the Washington, D.C. Metropolitan Area: A Protocol for a Natural Experiment Study(MDPI, 2018-02-13) Roberts, Jennifer D.; Hu, Ming; Saksvig, Brit Irene; Brachman, Micah L.; Durand, Casey P.Approximately two-thirds of adults and youth in Prince George’s County, Maryland, a suburb of Washington, D.C. are overweight or obese and less than half are achieving daily physical activity recommendations. Active transportation (AT), such as walking, biking or using public transportation (PT), is a strategic pathway to improving physical activity levels and thus reducing excess weight. Utilizing an expansion of the Washington, D.C. area transportation system with a new light rail line, the Purple Line Outcomes on Transportation (PLOT) Study will exam pre- and post-Purple Line PT use, AT behaviors and attitudes and physical activity among Prince George’s County adults and youth. The PLOT Study will take advantage of this natural experiment in an area enduring significant racial/ethnic and gender-based overweight or obesity and physical inactivity disparities. While similar natural experiments on AT have been conducted in other U.S. cities, those studies lacked diverse and representative samples. To effectively evaluate these physical activity outcomes among this population, efforts will be used to recruit African American and Latino populations, the first and second most common racial/ethnic groups in Prince George’s County. Finally, the PLOT Study will also examine how contextual effects (e.g., neighborhood built environment) impact PT, AT and physical activity.Item Between Privilege and Oppression: An Intersectional Analysis of Active Transportation Experiences Among Washington D.C. Area Youth(MDPI, 2019-04-12) Roberts, Jennifer D.; Mandic, Sandra; Fryer, Craig S.; Brachman, Micah L.; Ray, RashawnThe use of active transportation (AT), such as walking, cycling, or even public transit, as a means of transport offers an opportunity to increase youth physical activity and improve health. Despite the well-known benefits of AT, there are environmental and social variables that converge on the AT experiences of low-income youth and youth of color (YOC) that have yet to be fully uncovered. This study uses an intersectional framework, largely focusing on the race-gender-class trinity, to examine youth AT within a context of transportation inequity. Theoretically guided by the Ecological Model of Active Transportation, focus groups were completed with two groups of girls (15 participants) and two groups of boys (nine participants) ranging between the ages of 12–15 years who lived within the Washington D.C. area. This research found race, gender, and class to be inhibitors of AT for both boys and girls, but with more pronounced negative influences on girls.Item The Color of Health: Residential Segregation, Light Rail Transit Developments, and Gentrification in the United States(MDPI, 2019-09-30) Tehrani, Shadi O.; Wu, Shuling J.; Roberts, Jennifer D.As the modern urban–suburban context becomes increasingly problematic with traffic congestion, air pollution, and increased cost of living, city planners are turning their attention to transit-oriented development as a strategy to promote healthy communities. Transit-oriented developments bring valuable resources and improvements in infrastructure, but they also may be reinforcing decades-old processes of residential segregation, gentrification, and displacement of low-income residents and communities of color. Careful consideration of zoning, neighborhood design, and affordability is vital to mitigating the impacts of transit-induced gentrification, a socioeconomic by-product of transit-oriented development whereby the provision of transit service “upscales” nearby neighborhood(s) and displaces existing community members with more affluent and often White residents. To date, the available research and, thus, overall understanding of transit-induced gentrification and the related social determinants of health are limited and mixed. In this review, an overview of racial residential segregation, light rail transit developments, and gentrification in the United States has been provided. Implications for future transit-oriented developments are also presented along with a discussion of possible solutions.Item Environments, Behaviors, and Inequalities: Reflecting on the Impacts of the Influenza and Coronavirus Pandemics in the United States(MDPI, 2020-06-22) Roberts, Jennifer D.; Tehrani, Shadi O.In the past century, dramatic shifts in demographics, globalization and urbanization have facilitated the rapid spread and transmission of infectious diseases across continents and countries. In a matter of weeks, the 2019 coronavirus pandemic devastated communities worldwide and reinforced the human perception of frailty and mortality. Even though the end of this pandemic story has yet to unfold, there is one parallel that is undeniable when a comparison is drawn between the 2019 coronavirus and the 1918 influenza pandemics. The public health response to disease outbreaks has remained nearly unchanged in the last 101 years. Furthermore, the role of environments and human behaviors on the effect and response to the coronavirus pandemic has brought to light many of the historic and contemporaneous inequalities and injustices that plague the United States. Through a reflection of these pandemic experiences, the American burden of disparity and disproportionality on morbidity, mortality and overall social determinants of health has been examined. Finally, a reimagination of a post-coronavirus existence has also been presented along with a discussion of possible solutions and considerations for moving forward to a new and better normal.
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