16 Clinical Trials for Various Conditions
Metabolic flexibility is the capacity to adapt fuel oxidation to fuel availability so that ATP synthesis can match its cellular demands. Thus, for example, increases in glucose availability after a meal would increase glucose oxidation, while increases in lipid availability during fasting would increase lipid oxidation. Enhanced metabolic flexibility has been proposed to protect humans from metabolic diseases. Nevertheless, most studies examining associations between metabolic flexibility and metabolic health outcomes have used cross-sectional designs. Whether impaired metabolic flexibility causes or results from metabolic health impairment is thus unclear. In this study, the investigators will use the data from a study conducted approximately 16 years ago in healthy participants without obesity. Using the data already collected in that study, the metabolic flexibility of each participant will be calculated. To test the association between metabolic flexibility and the change in metabolic health, the investigators will call back all the participants for a single follow-up visit to reassess several metabolic health outcomes. Thus, the main aim of the study is to test the association between metabolic flexibility and the change in metabolic health outcomes after 16 years in humans.
The purpose of this study is to determine the impact of real-world shiftwork on metabolic flexibility.
This study is designed to test the reliability of a novel procedure for measuring metabolic flexibility, i.e., the ability to quickly adapt macronutrient oxidation to macronutrient availability, in a respiratory chamber. The investigators will compare paired measurements of metabolic flexibility determined 5-7 days apart in a metabolic chamber to assess reliability. The investigators will also compare their novel method of measuring metabolic flexibility in a respiratory chamber with a more convention method, metabolic flexibility during a hyperinsulinemic clamp.
The purpose of the study is to determine if a 6-week exercise training program promotes exercise-induced metabolic flexibility, that is, the ability to switch fuel sources for energy, in older prediabetic adults.
The overarching aim of this study: To determine the effect of different meal compositions (high- vs. low-fat) on metabolic flexibility as it relates to meal-stimulated change in respiratory quotient (ΔRQ1) and sleep (ΔRQ2) metabolic flexibility, as well as the time course changes in respiratory quotient, RQ (i.e., peak RQ, time to peak RQ, nadir RQ, time to nadir, slope).
This study will explore differences in energy metabolism and metabolic flexibility under various conditions in older men and women.
Consumption of slowly digestible carbohydrates can elicit higher satiety feeling compared to rapidly digestible carbohydrates, however not all individuals respond the same. The physiological mechanism that accounts for the satiety effect and the lack of consistency among subjects is not fully understood. The overall aim of this research is to determine if consumption of slow digestible carbohydrates can induce non-responding subjects (i.e., with rapid gastric emptying) to activate the ileal brake and delay rate of gastric emptying.
The purpose of this study is to measure the metabolic phenotype of a range of body weights in individuals with and without type 1 diabetes.
The investigators hypothesize that a dietary intervention aimed at increasing unsaturated fatty acids (UFA) consumption is feasible and has the potential to improve cardiorespiratory fitness, metabolic flexibility and glucose tolerance in symptomatic obese heart failure with preserved ejection fraction (HFpEF) patients.
The investigators propose in this project to determine the effect of 3 days of frequent interruption of prolonged sitting on metabolic health in healthy overweight sedentary adults (n=24), as compared to 3 days including a single long bout of isocaloric exercise or a control condition where subjects do not exercise but are subjected to prolonged sitting. The investigators believe that this proposed project will provide an initial evidence base for the health benefits of breaking up prolonged sitting with short bursts of moderate-intensity activity, like walking.
The objective is to develop a new metabolic flexibility biomarker, which has application in the study of changes diet and exercise on fuel management in humans. The new biomarker involves the characterization of an individual's metabolic flexibility utilizing room calorimeters rather than the current method, which is based on glucose clamp data. It is hypothesized that this new metabolic flexibility method will be a useful and noninvasive biomarker for measuring adaptation to exercise and diet challenges.
Briefly, this study involved 2 trials: baseline (Trial 1) and post-astaxanthin intervention (Trial 2). Both trials included participants completing a graded exercise test while connected to a metabolic cart, to measure cardiorespiratory measures. Between trials, participants were supplemented with either 12 mg of astaxanthin or placebo for 4 weeks. It was hypothesized astaxanthin supplementation would increase rates of fat oxidation, while decreasing carbohydrate oxidation and blood lactate accumulation.
This is a pilot study in 10 men to test the hypothesis that perturbations in substrate flux and the circulating metabolic and pro-inflammatory milieus during a high-fat diet paradigm will modulate DNA methylation of genes in sperm associated with obesity and cardiometabolic dysfunction.
African American women have a high prevalence of obesity and type 2 diabetes and do not optimally burn fat and carbohydrates in response to changes in these nutrients in their diets. This research project seek to determine if high intensity interval training (HIIT) exercise training can help healthy, but inactive, premenopausal, non-diabetic women increase their bodies' use of fat and carbohydrates when provided with a high fat or low fat diets. In this study, investigators will measure the rate at which fat is burned in response to weight maintaining low-fat and high-fat diets and how exercise may affect these responses.
This study, at the Western Human Nutrition Research Center (WHNRC), will focus on whether or not achieving and maintaining a healthy body weight is the most important health promoting recommendation of the Dietary Guidelines for Americans (DGA).The investigators hypothesize that improvement in cardiometabolic risk factors resulting from eating a DGA style diet will be greater in people whose energy intake is restricted to result in weight loss compared to those who maintain their weight. The investigators further propose that during a state of energy restriction, a higher nutrient quality diet such as the DGA style diet pattern, will result in greater improvement in cardiometabolic risk factors compared to a typical American diet (TAD) pattern that tends to be lower nutrient quality (more energy-dense and less nutrient-rich.)
The purpose of this study is to determine the impact of consuming cocoa on blood glucose levels, glucose metabolism, and other markers of pre-diabetes in overweight and/or obese individuals. Our hypothesis is that consumption of cocoa improves insulin sensitivity and glucose metabolism in subjects at risk for developing type-2 diabetes.