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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Glucose and insulin responses to a carbohydrate snack in carbohydrate cravers and non-carbohydrate cravers

Aberle, Susan E. 31 October 1990 (has links)
The controversial condition of carbohydrate craving is believed by some researchers to be a defect in the regulation of food intake by an individual. This defect is believed to be responsible for the inability of some persons to control their food intake and therefore their weight. Research was conducted to test the hypothesis that, given a group of carbohydrate cravers and a group of noncravers, the cravers will experience a greater plasma insulin response (concentration and area under the curve) than will the noncravers, and that, because of this higher response, the cravers will experience equal or lower plasma glucose levels during a carbohydrate load. A second hypothesis was that, because of cephalic insulin response due to sensory stimuli, cookies would elicit a greater plasma insulin response than would a glucose solution. This higher plasma insulin response may in part explain the uncontrollable snacking that some individuals experience. The purpose of this research was to attempt to identify a biochemical distinction between persons who crave carbohydrates and persons who do not crave carbohydrates. Eleven overweight female subjects, age 30 to 40, were recruited and divided into two groups, five carbohydrate cravers and six noncravers, based on scores received on a questionnaire that was devised for this study to attempt to distinguish between the groups. A Restrained Eating questionnaire was also administered to the subjects. Both groups had similar, but high, restrained eating scores, indicating that all of the subjects were probably restrained eaters. The eating restraint, as supported by the reported frequency of dieting among the subjects, may well have influenced the subjects' responses to the carbohydrate craving questionnaire. Utilizing these two groups of subjects, two tests were administered. The oral glucose tolerance test was administered, utilizing 75 g of carbohydrate each in the forms of glucose solution and cookies, which were administered in a random order. The tests were administered during the premenstrual phase of the subjects' menstrual cycles, 0-10 days prior to the onset of menstruation. Blood was drawn and assayed for plasma glucose and insulin. The research showed that the cravers experienced a significantly greater plasma insulin concentration and area under the curve than the noncravers, particularly at the 30, 60 and 120 minute time points with the glucose treatment. For the glucose treatment, the cravers experienced plasma insulin concentrations that were 32% to 50% greater than those of the noncravers in the early portion of the test. This supports the hypothesis which states that cravers will experience a greater plasma insulin response to a carbohydrate load than will noncravers. This elevated plasma insulin level may be responsible for the carbohydrate cravings that the individuals experience. There was no significant difference in plasma glucose levels at any time point in either of the tests as compared between the cravers and noncravers, thus supporting the expectation that these levels would be similar between the groups. The hypothesis that cookies would elicit a greater plasma insulin response than would a glucose solution was not supported. Any cephalic insulin response which may have resulted from the sight and smell of the cookies, while not specifically measured, was not strong enough to override the physiological factors that control insulin release. Therefore, the glucose solution elicited a significantly greater plasma insulin concentration than did the cookies in the cravers during the first two hours of the tests, and a significantly greater area under the curve for the cravers at 60 minutes and both groups at 120 minutes. However, the cookies did have an effect on insulin release at the fasting point, causing elevated (x = 79%) plasma insulin levels in three of five subjects who were waiting while others were eating the cookies, as compared with these subjects' fasting insulin levels when they were not exposed to the cookies prior to their glucose test. Another finding was a difference between the groups in fasting plasma insulin concentrations over the 10 day premenstrual portion of their menstrual cycles. The noncravers experienced fasting plasma insulin concentrations that decreased as the onset of menstruation was approached, which would parallel the decrease in progesterone levels. However, the cravers experienced first a decrease in fasting plasma insulin levels to day 3 premenstrual, and then an increase to the level of that found 8-10 day premenstrual. This pattern is contrary to what would be expected as progesterone levels drop, and suggests an altered pattern of progesterone levels in the cravers, although progesterone was not measured in this study. To summarize, in a group of overweight women, carbohydrate cravers and non cravers, the cravers experienced a greater plasma insulin response than did the noncravers for the glucose treatment but not for the cookie treatment, and there was no significant difference between the groups for plasma glucose concentration for either treatment. / Graduation date: 1991
2

Supercompensated Glycogen Loads Persist 5 Days in Resting Trained Cyclists

Arnall, David A., Nelson, Arnold G., Quigley, Jack, Lex, Stephen, DeHart, Tom, Fortune, Peggy 01 February 2007 (has links)
Research data indicates a persistence of elevated muscle glycogen concentration 3 days post-supercompensation in resting athletes. This study expands our earlier findings by determining whether muscle glycogen remains elevated 3, 5, or 7 days post-supercompensation. Seventeen trained male cyclists underwent one bout of exhaustive exercise to deplete muscle glycogen. This was followed by a 3-day consumption of a high carbohydrate/low protein/low fat diet (85:08:07%). Three post-loading phases followed with subjects randomly assigned to either a 3-day, 5-day, or 7-day post-loading maintenance diet of 60% carbohydrate and limited physical activity. Biopsies (50-150 mg) of the vastus lateralis were obtained pre-load (BASELINE), at peak-load (PEAK), and either at 3-day, 5-day, or 7-day post-load (POST). On average, PEAK to POST muscle glycogen concentrations decreased 34, 20 and 46% respectively for the 3-, 5-, and 7-day POST groups. Only the 7-day post-load group's PEAK to POST mean muscle glycogen concentration decreased significantly. In addition, multi-regression analysis indicated that the PEAK glycogen level was the main determinant of the number of days that glycogen levels remained significantly greater than BASELINE. Thus, trained athletes-supercompensated glycogen levels can remain higher than normal for up to 5 days post-loading. The amount of carbohydrate consumed, the level of physical activity, and the magnitude of the glycogen supercompensation determine the interval for which the glycogen levels are elevated.
3

Praktické aspekty vysokosacharidové diety ve vrcholovém sportu / Practical aspects of high-carbohydrate dieting in top sport

Jurková, Kateřina January 2019 (has links)
Topic: Practical aspects of high-carbohydrate dieting in top sport The topic of this thesis is sports nutrition. After a comprehensive summary of current scientific and generally accepted guidelines, the practical part is based on an example of the current state of sports nutrition in one concrete men's basketball team. Subsequently, the practical part combines the knowledge of theory and results of diet analysis of the current nutritional status in the team. The aim of the analytical part of the thesis was to find out the individual and subsequently average data of the monitored file through the registration of weekly eating diaries, both in terms of macro and micronutrients. These data were statistically processed using the program Sportvital-Nutrition (http://www.bonfit.cz/), whose database contains the most comperhensive information about the composition of individual foods and meals, allowing analysis of up to 30 nutritional parameters. The main aim of the application part of the thesis was to design and calculate a sample menu for seven whole days for top athletes based on predetermined and defined criteria based on theoretical background and analysis of collected eating diaries. These criteria were to follow the principles of healthy nutrition, i.e. primarily the variety, regularity and...
4

Effects of high-carbohydrate and low-fat versus high-protein and low-carbohydrate diets on high-intensity aerobic exercise /

Toma, Kumika. January 2009 (has links)
Thesis (Ph.D.)--Ohio University, August, 2009. / Release of full electronic text on OhioLINK has been delayed until September 1, 2012. Includes bibliographical references (leaves 157-195)
5

Effects of high-carbohydrate and low-fat versus high-protein and low-carbohydrate diets on high-intensity aerobic exercise

Toma, Kumika. January 2009 (has links)
Thesis (Ph.D.)--Ohio University, August, 2009. / Title from PDF t.p. Release of full electronic text on OhioLINK has been delayed until September 1, 2012. Includes bibliographical references (leaves 157-195)
6

Carbohydrate utilization in selected strains of British Columbia chinook salmon

Mazur, Carol Nelson January 1990 (has links)
Digestible carbohydrate is commonly encountered by chinook salmon {Oncorhynchus tshawytscha) in practical culture diets, although little is known regarding its utilization. This study was undertaken to examine (1) the effects of a high carbohydrate diet and (2) glucose tolerance in chinook salmon of selected British Columbia strains. Yearling chinook salmon of three strains were fed to satiation either a high or a low carbohydrate diet for 63 days. The diets were isonitrogenous, and contained respectively 30 % gelatinized wheat starch or an equicaloric amount of herring oil. There was an overall reduction in growth of chinook fed the high-carbohydrate diet over the 63-day feeding period. Although specific growth rates declined initially in the high carbohydrate-fed groups, they were comparable to those of control groups in the final third of the trial, indicating an adaptation response. Chinook fed the high carbohydrate diet had increased carcass protein and ash, and decreased carcass fat levels relative to controls. Feed intake was generally lower in these groups, and differences in feeding response were observed between diets and strains. Although feed and energy efficiencies were reduced in chinook fed the high carbohydrate diet, protein utilization was comparable on the two diets, indicating a protein-sparing effect of the carbohydrate. Consumption of the high carbohydrate diet led to significant elevations in hepatosomatic indices (HSI) and liver glycogen (LG) concentrations. In Quesnel chinook, LG levels exceeding 10 % did not appear to have any detrimental effects on feeding, growth or health. LG concentrations and HSI fell to basal levels in all groups 21 days after feed withdrawal. Some strain differences were evident. For example, Big Qualicum chinook fed the high carbohydrate diet exhibited the lowest liver glycogen accumulation, highest rate of carcass fat deposition, and best energy efficiency ratios relative to control groups, suggesting a difference in carbohydrate metabolism in this strain. On the other hand, Quesnel chinook exhibited the highest relative growth on the high carbohydrate diet. Mortality, although unaffected by diet in the Quesnel and Robertson Creek chinook, appeared to be higher in high carbohydrate-fed Big Qualicum chinook. In the second part of the study, chinook salmon subjected to an oral glucose tolerance test displayed pronounced and persistent hyperglycaemia, indicative of poor glucose tolerance. Strain differences were evident in the magnitude of response. Acclimation to a high carbohydrate diet prior to testing resulted in a significantly reduced elevation of blood glucose, indicating an adaptation response. While plasma glucose concentrations approached 500 mg/dl in some trials, plasma insulin concentrations exhibited a two-fold rise, with indistinct peaks. Plasma glucose and plasma insulin concentrations were poorly correlated, indicating that glucose is a poor insulin secretagogue in chinook salmon. / Land and Food Systems, Faculty of / Graduate
7

Carbohydrate loading and its effect on ECG responses

Karam, Christopher January 1983 (has links)
Six white volunteer males less than 35 years old, who ran less than 35 miles per week completed a loading regimen. This consisted of a succession of mixed, high-fat and highCHO diets for at least 72 hours each. Subjects ran to exhaustion after each diet stage. Mean times to exhaustion were 61, 63 and 95 minutes for the mixed, high-fat, and high-CHO diets, respectively. Since questions have been raised concerning a detrimental effect of CHO-loading on heart function, subjects were closely examined for evidence of negative effects associated with this procedure. An incomplete right bundle branch block (RBBB), sinus arrhythmia, and early repolarization after the mixed diet was noted in three of the six subjects. These changes were not observed during the high-fat nor high-CHO diets. Prior to the high-CHO exhaustive run, it was also found that the width of the QRS complex was significantly more narrow than the mixed and high-fat diets. The above electrocardiographic (ECG) changes were noted as not being clinically significant by an internal medicine physician. No changes were noted in blood pressures, serum free fatty acids (FFA) and post exhaustive run body weights for diets not pre/post exercise bouts. Serum glucose was significantly higher for the pre-run high-CHO diet when compared to the mixed and high-fat diets pre-run values, yet it remained within normal limits. Body weight following the high-CHO diet was significantly greater than during the high-fat and mixed periods. This may be due to water retention occurring with increased glycogen storage. This probably explains the longer time to exhaustion for the high-CHO diet as compared to the mixed and high-fat trials which both yielded similar times to exhaustion. Although research indicates that a mixed diet prolongs the onset of exhaustion more than a high-fat diet, the similar endurance capacity for the high-fat and mixed diets could be related to a learning effect on the treadmill and/or psychological considerations of consuming a high-fat diet. Also since heart rate and blood pressure were not significantly different for the first 30 minutes of exercise while rate of perceived exertion (RPE) indicated the mixed diet trial most demanding and the high-CHO trial least, one might suspect that some other factor besides physiological values, may cause fatigue. In summary, CHO-loading appeared to enhance endurance of the novice runner with no apparent detrimental effects on cardiac function in these six subjects. / Master of Science
8

Calories vs. composition : the effects of dietary alterations on anthropometric measures and biochemical parameters in overweight women / Effects of dietary alterations on anthropometric measures and biochemical parameters in overweight women

Riggs, Amy Jo January 2002 (has links)
TITLE: Calories vs. Composition: The effect on dietary alterations on anthropometric measures and biochemical parameters in overweight women.LEARNING OUTCOME: To determine if a high-protein, low-carbohydrate, ad-libitum diet is more effective than an energy-restricted diet in promoting weight loss and improving blood lipid and insulin levels.ABSTRACT TEXT: Thirty overweight/obese (BMI: 25-35kg/m2), premenopausal women were matched for Body Mass Index (BMI) and randomly assigned to one of the two diets: (1) High Protein (HP) (30-40% protein, 40-55% fat, 10-20% CHO); (2) Energy Restricted (ER) (1200kcal/d, 20-25% fat, 15-20% protein, 55-60% CHO). Subjects were given weekly menus matching their assigned macronutrient and/or energy requirements to aid in meal planning and dietary compliance. Baseline and post-diet measures included height, weight, body composition, blood lipids (total cholesterol (TC), HDL, LDL< and triglycerides (TG)], and plasma insulin levels. There were no significant differences found among the two groups in any of the above-listed variables prior to the study. Twenty-three women completed the 6-week study (HP=11, ER= 12). Compliance to the diets was adequate as indicated by weekly 24-hour recalls and daily urinary ketone levels. Both groups lost a significant amount of weight and body fat (P<0.05), andweight and body fat losses were not significantly different between the groups. In addition, both groups experienced similar decreases in TG, TC, LDL, HDL, and insulin levels. These results indicate that a HP diet is no more effective than an ER diet in promoting favorable changes in body weight, body composition, blood lipids, and insulin levels. / Department of Family and Consumer Sciences
9

Effects of a high protein diet on weight loss, markers of health, and functional capacity in senior-aged females participating in the Curves [Registered] fitness program

Galbreath, Melyn. Kreider, Richard B., January 2008 (has links)
Thesis (Ph.D.)--Baylor University, 2008. / Includes bibliographical references (p. 161-180)
10

Efeitos da dieta hipoproteica-hiperglicídica sobre o metabolismo desiodativo e as ações periféricas dos hormônios tireóideos

Mezaroba, Deise Fátima 30 April 2015 (has links)
Submitted by Valquíria Barbieri (kikibarbi@hotmail.com) on 2018-04-18T21:12:08Z No. of bitstreams: 1 DISS_2015_Deise Fátima Mezaroba.pdf: 1567664 bytes, checksum: 67bbe66382033d0b60709a1c450df069 (MD5) / Approved for entry into archive by Jordan (jordanbiblio@gmail.com) on 2018-04-27T17:30:42Z (GMT) No. of bitstreams: 1 DISS_2015_Deise Fátima Mezaroba.pdf: 1567664 bytes, checksum: 67bbe66382033d0b60709a1c450df069 (MD5) / Made available in DSpace on 2018-04-27T17:30:42Z (GMT). No. of bitstreams: 1 DISS_2015_Deise Fátima Mezaroba.pdf: 1567664 bytes, checksum: 67bbe66382033d0b60709a1c450df069 (MD5) Previous issue date: 2015-04-30 / CAPES / A dieta hipoproteica-hiperglicídica (LPHC), administrada a ratos machos por 15 ou 45 dias, logo após o desmame, altera vários parâmetros metabólicos e hormonais. Sabe-se também que os hormônios produzidos pela glândula tireoide têm um papel fundamental a nível tecidual para a manutenção da homeostase do organismo. Diante disto, o objetivo deste trabalho foi investigar os efeitos da dieta LPHC a longo prazo e da troca da dieta LHPC por dieta balanceada sobre o metabolismo desiodativo em diferentes tecidos, assim como algumas das ações atribuídas aos hormônios tireóideos. Ratos Wistar machos (~100g) foram randomicamente divididos em grupos conforme segue: 1) controles - alimentados com uma dieta com 17% de proteínas e 63% de carboidratos por 45 dias (C45); 2) LPHC - alimentados com dieta contendo 6% de proteínas e 74% de carboidratos por 45 dias (LPHC45) e; 3) reversão - alimentados por 15 dias com a dieta LPHC e por mais 30 dias com a dieta controle (R) (ANOVA-1 via; p<0,05). A quantificação da concentração do hormônio tireoestimulante no sangue dos animais do grupo R mostrou um aumento de 11,7% e 11,6%, se comparado ao grupo C45 e ao grupo LPHC45, respectivamente (C45: 8439,58 ± 59,46; LPHC45: 8448,06 ± 105,86; R: 9428,39 ± 48,96 pg/mL). A análise da expressão proteica da iodotironina desiodase 1 em fígado, rins e tireoide e da iodotironina desiodase 2 em tecido adiposo marrom, músculos extensor digital longo e sóleo, hipotálamo e hipófise mostrou alteração somente no fígado do grupo LPHC45, com aumento de 17,38% da isoforma 1, em relação aos animais controles. Este grupo também apresentou aumento de 27,02% no conteúdo do receptor hepático para hormônio tireóideo β1, comparando-se ao grupo C45. A avaliação do perfil lipídico de jejum mostrou redução do colesterol total (C45: 97,35 ± 7,87; LPHC45: 65,41 ± 4,78; R: 94,32 ± 5,25 mg/dL), colesterol HDL (C45: 56,58 ± 3,90; LPHC45: 36,74 ± 1,28; R: 54,21 ± xvii 4,30 mg/dL), colesterol VLDL (C45: 22,92 ± 1,44; LPHC45: 15,89 ± 1,50; R: 22,07 ± 1,70 mg/dL) e triglicerídeos (C45: 114,61 ± 7,18; LPHC45: 79,46 ± 7,49; R: 110,36 ± 8,48 mg/dL) nos animais submetidos à dieta LPHC por 45 dias. A expressão hepática da enzima 7α-hidroxilase e da proteína de ligação ao elemento de resposta aos esteróis aumentou 43,96% e 36,27%, respectivamente, no grupo LPHC45, quando comparadas ao grupo C45. A atividade das enzimas málica (C45: 85,92 ± 9,01; LPHC45: 171,63 ± 14,98; R: 159,09 ± 13,16 nmol.mg prot-1.min-1) e ATP-citrato liase (C45: 290,88 ± 11,57; LPHC45: 444,98 ± 20,79; R: 386,75 ± 23,47 nmol.mg prot-1.min-1) foi maior nos grupos LPHC45 e R, em relação ao grupo C45. A análise conjunta destes dados demonstra que a dieta hipoproteica-hiperglicídica administrada por 45 dias leva a alterações no metabolismo desiodativo hepático, modulando o perfil lipídico e que talvez possam resultar em um futuro quadro de esteatose hepática. / The low-protein, high-carbohydrate diet (LPHC) administered to male rats for 15 or 45 days after weaning, change various metabolic and hormonal parameters. It is also known that the hormones produced by the thyroid gland have a key role to tissue level to maintain body’s homeostasis. Thus, the objective of this study was to investigate the effects of the LPHC diet long-term and exchange of LHPC diet for balanced diet on the deiodinative metabolism in different tissues, as well as some of the actions attributed to thyroid hormone. Male Wistar rats (~100g) were randomly divided into the following groups: 1) controls - fed a diet containing 17% protein and 63% carbohydrates for 45 days (C45 group); 2) LPHC - fed a diet containing 6% protein and 74% carbohydrates for 45 days (LPHC45 group), and 3) reversal - fed for 15 days with LPHC diet and for 30 days with the control diet (R group) (ANOVA-one way; p<0.05). The quantification of the concentration of thyroid-stimulating hormone in the blood of the animals of the R group showed an increase of 11.7% and 11.6%, compared with the C45 group and LPHC45 group, respectively (C45: 8439.58 ± 59.46; LPHC45: 8448.06 ± 105.86; R: 9428.39 ± 48.96 pg/mL). Analysis of protein expression of iodothyronine deiodinase 1 in liver, kidney and thyroid, and protein expression of iodothyronine deiodinase 2 in brown adipose tissue, long digital extensor and soleus muscles, hypothalamus, and pituitary only showed alteration in liver of the LPHC45 group, with an increase of 17.38% in the isoform 1, compared with the control animals. This group also showed an increase of 27.02% in the content of liver receptor for thyroid hormone β1 compared with the C45 group. The fasting lipid profile showed a reduction in total cholesterol (C45: 97.35 ± 7.87; LPHC45: 65.41 ± 4.78; R: 94.32 ± 5.25 mg/dL), in HDL cholesterol (C45: 56.58 ± 3.90; LPHC45: 36.74 ± 1.28, R: 54.21 ± 4.30 mg/dL), in VLDL (C45: 22 92 ± 1.44; LPHC45: 15.89 ± 1.50; R: 22.07 ± 1.70 mg/dL), xix and triglycerides (C45: 114.61 ± 7.18; LPHC45: 79.46 ± 7 49; R: 110.36 ± 8.48 mg/dL) in animals subjected to LPHC diet for 45 days. The hepatic expression of 7α-hydroxylase enzyme and the binding protein sterol response element had an increase of 43.96% and 36.27%, respectively, in LPHC45 group when compared with the C45 group. The activity of malic enzyme (C45: 85.92 ± 9.01; LPHC45: 171.63 ± 14.98; R: 159.09 ± 13.16 nmol.mg prot-1 .min-1) and ATP-citrate lyase (C45: 290.88 ± 11.57; LPHC45: 444.98 ± 20.79; R: 386.75 ± 23.47 nmol.mg prot-1 .min-1) was higher in LPHC45 and R groups, compared with C45 group. The analysis of these data shows that the low-protein, high-carbohydrate diet administered for 45 days leads to alterations in hepatic deiodinative metabolism by modulating the lipid profile and that may perhaps result in a future framework of hepatic steatosis.

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