Browsing by Subject "Body composition"

Now showing 1 - 3 of 3
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    Application of Network Meta-Analysis in The Field of Physical Activity and Health Promotion: A Case Study
    (2020-08) Su, Xiwen
    Continued advancement in the field of kinesiology and health promotion relies heavily on the synthesis of rigorous quantitative scientific evidence. As such, meta-analyses of randomized controlled trials have led to a better understanding of what intervention strategies are superior (i.e., produce the greatest effects) in physical activity-based health behavior change interventions. Indeed, standard meta-analytic approaches have allowed researchers in the field to synthesize relevant experimental evidence using pairwise procedures which produce reliable estimates of the homogeneity, magnitude, and potential biases in the observed effects. However, pairwise meta-analytic procedures are only capable to discerning differences in effects between a select intervention strategy and a select comparison condition or control condition. In order to maximize the impact of physical activity interventions on health-related outcomes, it is necessary to establish evidence concerning the comparative efficacy of all relevant physical activity intervention strategies. The development of network meta-analysis (NMA)—most commonly used in medical-based clinical trials—has allowed for the quantification of indirect comparisons, even in the absence of direct, head-to-head trials. Thus, it stands to reason that NMA can be applied in the physical activity and health promotion research to identify the best intervention strategies. Given this analysis technique is novel and largely unexplored in the field of kinesiology and health promotion, care must be taken in its application to ensure reliable estimates and discernment of the effect sizes between interventions. Therefore, the purpose of this study is to first comment on the potential application and importance of NMA in the field of kinesiology and health promotion, then describe how to properly and effectively apply this technique using a specific case study evaluating the effects of different lifestyle interventions on children’s body composition, and lastly suggest important considerations for its appropriate application in this field. In this paper, overviews of the foundations of NMA and commonly used approaches for conducting NMA are provided, followed by assumptions of NMA, opportunities and challenges in NMA, and a case study example of the development and conduct of an NMA, as well as the interpretation of the analysis results. The case study collect original data from published randomized controlled studies investigating on some type of intervention on variables including body mass index (BMI), BMI z-score (BMIz), and body fat percentage, divided the used intervention into ten categories in total, from simple single intervention to multiple components mixed intervention (more than three), and used pre-processed data to carry out network meta-analysis. Results of analysis using mean difference (SD) between baseline and immediate post-intervention data showed that PA intervention ranked top two of the most effective approaches among other types of lifestyle interventions in all three variables, suggesting that promoting PA participation is crucial in children’s health status and childhood obesity control. While based on the analysis using combined original pre-and-post data (SE), multiple component interventions were predicted to be the best ranked intervention approach among all ten types of intervention, indicating that taking care of more aspects in children’s lifestyle may also result in an important impact for children to keep healthy and fit.
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    Body composition, nutrient intake and MTHFR genotype in patients with peripheral arterial disease
    (2014-05) Brostow, Diana P.
    Background: Peripheral artery disease (PAD) is a progressive disease characterized by its impact on physical mobility, and a high rate of vascular comorbidities and events. Despite its inclusion in the same grouping of conditions as cardiovascular (CVD) and cerebrovascular diseases, PAD garners much less attention, both in a clinical setting and in research. There is a significant body of research on the roles of nutrition and lifestyle in CVD and stroke etiology, yet the equivalent data for PAD is sparse. The impact of nutrition and related factors on PAD is poorly understood, and in need of expansive clarification.Methods: We conducted a literature review of all available research on nutrition and body composition in PAD, and used our assessments to design a cross-sectional study of these variables in a sample of PAD patients. We created a conceptual model of how nutrition-related variables may be associated with various aspects of PAD severity, and examined these associations within recruited participants.Results: Participants diets' were characterized by relatively high intakes of fat, sugar and sodium, as well as by low or inadequate intakes of crucial micronutrients. Several dietary factors were found to be significantly associated with more severe physical or psychosocial PAD symptoms. The majority of participants were also overweight or obese, and total body weight and abdominal obesity were associated with worse scores on tests of PAD severity. Additionally, we encountered several key obstacles to identifying and recruiting patients for this study. Conclusions: Although our sample size was relatively small, there is evidence to suggest that there are nutrition-related factors that are associated with the severity of PAD patients' symptoms and overall quality of life. Recruitment methods are in need of revision to obtain larger, more statistically powered samples, and we have outlined potential approaches for doing so. Lastly, this study establishes a precedent for future studies to implement interventions in PAD patients using already-established vascular guidelines for nutrition.
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    Quantification of visceral fat using dual energy X-ray absorptiometry
    (2014-05) Bosch, Tyler A.
    Accumulation of visceral adipose tissue is an independent marker for cardiovascular risk and insulin resistance in both children and adults (Gower et al, 1999; Neeland et al. 2012; Owens et al. 1998). As the accumulation of visceral adipose tissue increases the risk of cardiovascular also increases independently of total obesity (Nakamura et al. 1993). Given its location surrounding the visceral organs, accurate measurement of visceral adipose tissue presents a challenge. The first reliable methods for quantifying visceral adipose tissue were computed tomography and magnetic resonance imaging. These procedures, while valid and reliable, are associated with several limitations and generally rely on a single slice to estimate visceral adipose tissue. Recently, dual energy x-ray absorptiometry (DXA) has been validated against computed tomography as a valid and reliable estimate of visceral adipose tissue (Kaul et al. 2012) and a significant marker of cardiometabolic risk in adults (Katzmarzyk, et al. 2013; Rothney et al. 2013). This dissertation will investigate the use of this novel method in three distinct populations: children; adults; and professional football players. We hypothesize that DXA will provide a valid estimate of visceral adipose tissue in children and be associated with cardiometabolic risk factors. Secondly, we hypothesize that differences in regional body composition exist in professional football players. Finally, we hypothesize that a threshold exists in distribution of fat to the visceral region and that this threshold is associated with increased cardiometabolic risk. The results of this dissertation will provide further insight into the reliability and clinical utility of DXA for estimating visceral adipose tissue.