• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 382
  • 255
  • 67
  • 30
  • 15
  • 9
  • 8
  • 7
  • 7
  • 7
  • 7
  • 7
  • 7
  • 6
  • 5
  • Tagged with
  • 960
  • 960
  • 338
  • 331
  • 163
  • 146
  • 103
  • 99
  • 95
  • 94
  • 92
  • 92
  • 88
  • 85
  • 76
  • 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.
101

The influence of BMI on the relationship between heart rate reserve and VOb2s reserve / Influence of body mass index on the relationship between heart rate reserve and oxygen uptake reserve

Thatcher, Laura M. January 2005 (has links)
The American College of Sports Medicine advocates the use of a percentage of maximal oxygen uptake reserve (%VO2R) for exercise prescription purposes because it's thought to provide a close match with percentage of heart rate reserve (%HRR) than a given percentage of maximal oxygen uptake (%VO2max). However, some recent studies have challenged the validity of this matching. The purpose of this study was to assess the association of body mass index (BMI) with the matching of %HRR and %VO2R during graded exercise testing. The study sample included 626 subjects (281 men; 345 women); mean age of 45.5+11.7 years; mean BMI of 27.9+5.4 kg .m-2) who completed a maximal treadmill test to volitional fatigue using the BSU/Bruce Ramp protocol. The distribution of BMI measures within the sample was 31.4% <25; 38% between 25.0 and 29.9; 17.9% between 30 and 34.9%; 8.8% between 35 and 39.9%; and 3.1% were > 40 kg•m"2. Subjects were excluded from the analysis if they failed to achieve a peak RER > LO during the maximal exercise test, possessed pulmonary or cardiovascular disease (excluding hypertension), or incomplete/erroneous submaximal heart rate and/or V02 data that was unable to be retrieved from subject's existing file. Heart rate and VO2 data from minutes 3, 6, and 9 were converted into %HRR and %VO2R, with 3.5 ml•kg-'•min' serving to represent resting VO2. The relative exercise intensity for minutes 3, 6, and 9 represented 39.7 +12.2, 62.9 ± 15.6, and 80.8 ± 12.5% of VO2R, respectively and 43.1 f 12.6, 64.7 ± 14.9, and 83.5 + 10.6% of HRR. %HRR significantly overestimated %VO2R at each measurement point during the exercise test with mean differences 3.3, 2.0, and 3.8%, respectively (p<0.05). The association of BMI with the matching of %HRR and %VO2R was assessed by correlation with the difference the scores (AHRRVO2R) at each specified time during exercise test. Correlations for BMI and AHRRVO2R were -0.102, -0.175, and -0.231 for minutes 3,6, and 9, respectively (p<0.05). These results demonstrate a low association between BMI and the matching of HRR and VO2R. / School of Physical Education, Sport, and Exercise Science
102

Within-Day Energy Balance and Protein Intake Affect Body Composition in Physically Active Young Adult Females

Hanson, Heather 09 June 2014 (has links)
Title: Within-Day Energy Balance and Protein Intake Affect Body Composition in Physically Active Young Adult Females Background: Past studies suggest that individuals who eat smaller, more frequent meals are at a metabolic advantage when compared to those who eat larger, less frequent isocaloric meals. Studies also suggest that consumption of small amounts (~ 20 to 30 g) of protein evenly distributed during the day, may be a superior strategy for satisfying the protein requirement and improving muscle protein synthesis. It was, therefore, the purpose of this study was to assess the relationship between body composition and the distributed consumption of energy and protein in physically active young adult females. Methods: Using an IRB approved protocol, physically active female volunteers were measured for height using a standard wall mount stadiometer; body composition and weight were measured using a multi-current 8-mode segmental bioelectrical impedance device (Tanita, Arlington Heights, Illinois USA, Model BC-418). The volunteers kept a food and activity journal for one day, which was assessed to determine hourly energy balance and hourly protein intake. Exertion was assessed using a relative intensity activity MET value scale that produces multiples of resting energy expenditure, which was predicted using the Harris-Benedict equation. Results: The 28 females who volunteered for this study ranged in age from 19-24 years. Significant inverse associations were found between protein (grams/kg) consumption and fat mass (r=-0.42; p=0.026); and FFM and the ratio of protein to energy balance at 4pm (r=-0.376; p=0.049). There was a significant positive association between FFM and the ratio of protein to energy balance at 12pm (r=0.390; p=0.040) and 9pm (r= 0.379; p=0.047). There was also a significant positive association between the ratio of FFM to height and the ratio of protein to energy balance at 12 pm (r=0.423; p=0.025). There was a significant association between highest daily peak energy balance and FFM to height ratio (r=0.402; p=0.034). Regression analysis determined that independent EB and protein variables could be used to predict the dependent variable FFM to Height ratio (r=.727; p=0.019). Conclusions: These findings demonstrate a significant positive association between highest daily EB and FFM to height ratio. The results also suggest that higher protein consumption per kg is inversely associated with fat mass. Similarly, when protein is consumed when in ±400 kcal energy balance, is associated with higher FFM. Additionally, energy balance and protein variables can be used to predict FFM to height ratio using a regression equation that accounts for 52.9% of variance. These data indicate that subjects spent far more hours in an energy balance deficit than surplus, making it difficult to assess the impact of protein intake distribution on body composition. It does appear that, from a relatively small subsample (n=28) who did achieve a positive within-day energy balance and adequate protein intake, consumption of protein while in good energy balance may help physically active adult females achieve a body composition that is low in fat mass and high in lean muscle mass.
103

Alterations in the macronutrient content of the diet and the effects on body composition, cardiovascular disease risk and the control of energy metabolism in obese patients with type 2 diabetes mellitus

Gryka, Anna January 2011 (has links)
Background/Objective: Several studies have shown that a low carbohydrate diet (LCHOD) can improve glycaemic control in type 2 diabetes (T2DM). The objective of the current study was to compare two ways of administration of a LCHOD: self-prepared meals versus ready-made meals, and their effects on weight loss, glycaemic control, body composition, cardiovascular risk and resting metabolic rate over 12 months. Research design and methods: Forty-one volunteers with the mean body mass index of 38.8 kg/m2 and poorly controlled T2DM (glycosylated haemoglobin, HbA1c > 7.5%) were randomized to either protein sparing modified fast (< 40g of carbohydrate daily, self-cooked; PSMF) or Go Lower (readymade meals; GL) diet. Both groups received multivitamin supplementation and attended monthly visits. The main outcome was weight loss and its composition. Results: Fourteen (34 %) participants completed 12 months of the intervention. There were no differences in the weight or any other changes between the diet groups at 12 months. Overall, body mass and fat mass decreased (-5.5 ± 7.3 kg, P < 0.001 and -5.1 ± 6.7 kg, P < 0.001 respectively) but fat free mass did not change. There was an overall reduction in HbA1c (-0.4 ± 1.1 %, P < 0.001), increase in HDL-cholesterol (+0.07 ± 0.18 mmol/L, P < 0.001) and decrease in triacylglycerol (-0.6 ± 2.4 mmol/L, P = 0.014). Resting metabolic rate significantly decreased (-137 ± 265 kcal/d, P < 0.001). Conclusion: LCHOD, independently of the approach taken, led to weight loss and improvements in glycaemic control in obese volunteers with poorly controlled T2DM. The results confirm that lifestyle modification using LCHOD is effective for improving T2DM and suggest that the type of approach to the diet can be matched to an individual’s preferences.
104

A Study of Lean Body Mass in Estimating Basal Metabolic Rate

Lachenbruch, Charles 05 1900 (has links)
The primary purpose of the study was to determine if measured LBM could be used as a more powerful predictor of BMR than could surface area (SA) as calculated by the formula of DuBois and DuBois (1916). It was also of interest to develop a prediction equation for BMR using multiple regression analysis. Data from 82 women and 76 men were included in the study. Pearson product-moment correlations indicated that LBM was a better predictor for BMR than SA on either of the principal SA prediction equations, those of Aub and DuBois (1917) and Harris and Benedict (1919). Age, sex, and fat weight were not found to contribute significantly to prediction when included by multiple regression analyses. Linear equations for BMR as a function of LBM were developed for each sex. Tables based on these equations were also generated as a quick reference for clinicians.
105

HUMAN BODY COMPOSITION DURING ONTOGENESIS

Koukou, Aikaterini January 2015 (has links)
1. ABSTRACT This diploma thesis refers to human body composition and its alterations by physiological and pathological processes that occur during different stages of life. Fat mass, fat free mass and total body water represent the major components of the human body which are modified during infancy, childhood, puberty, pregnancy and adulthood. Bioelectrical Impedance Analysis (BIA), Dual Energy Absorptiometry (DEXA), Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) are some methods which are utilized for the qualitative and quantitative assessment of the body composition according to nutritional and pathological state of each individual, targeting the optimal clinical outcome. During growth, the amount of total body water elevates through infancy but it gradually declines in the next stages of life. Fat mass or total body fat possesses higher values during infancy, pregnancy and aging whereas it increases preferentially in female population at puberty. Muscle mass is elevated significantly in males during puberty and declines gradually due to aging. Osteoporosis, obesity and wasting diseases such as anorexia, cachexia and sarcopenia provoke severe disturbances in body composition compartments resulting in high rates of morbidity and mortality of the population.
106

Energetický výdej a utilizace nutričních substrátů u pacientů se sepsí v průběhu hospitalizace na JIP / Energy expenditure and utilization of nutritive substrates in septic patients during hospitalization in ICU

Hladová, Eliška January 2014 (has links)
The aim of this work were examinations of septic patiens to determinate energy expenditure and the utilization of nutritional substrates and to compare results of examinations to standart recommendations of ESPEN for patient's nutrition. For investigations was used indirect calorimetry. Our group of septic patients consisted of three men and three women from 58 to 73 years old. The lenght of the hospital stay was different, so the group was heterogenous and each patient was in different phase of sepsis. Five of six patients were in hypermetabolism. The value of energy expenditure was from 87,3 % to 176,2 %. Average energy expenditure was 1790,3 ± 414,9 kcal/ kg/ day and average energy of nutrition was 2080,2 ± 754,7kcal/ kg/ day. As for nutritional substrates, average income of carbohydrates was 257,9 ± 109,9 g/ den. Average utilization of carbohydrates was 83,9 ± 62,1 g/ day. So the intake of carbohydrates were significantly higher, than the utilization. Average income of lipids was 63,6 ± 15,7 g/ day and average utilization was 102,1 ± 61,8 g/ day. There was also significant diference between lipid utilization and lipid intake. Average income of proteins was 127,4 ± 61,7 g/ day. Average utilization of proteins was 132,5 ± 53,6 g/ day. To conclusion, the results of examinations, measured by...
107

Composição corporal de mulheres no climatério

Oliveira, Pablo Gustavo de January 2017 (has links)
Objetivos: Avaliar o efeito da menopausa sobre a composição corporal, a distribuição de gordura abdominal, o índice de massa corporal, a circunferência cintura, os percentuais de gordura androide, ginoide e a relação androide/ginoide, o consumo calórico total da alimentação diária e o nível de atividade física de mulheres climatéricas. Modelo: Estudo transversal com mulheres climatéricas recrutadas através de divulgação nas mídias eletrônica e impressa e realizado de março de 2014 a outubro de 2015. Local: Centro de Pesquisa Clínica do Hospital de Clínicas de Porto Alegre (CPC/HCPA), RS/Brasil. Amostra: A amostra foi constituída por mulheres na pré e pós-menopausa com idade entre 44 e 52 anos. Medidas de avaliação: Os instrumentos utilizados foram: Executive summary of the Stages of Reproductive Aging Workshop + 10 (STRAW +10, para a classificação de mulheres em relação ao estadiamento menopausal); Recordatório alimentar de 24 horas (para medir o consumo alimentar); um questionário semiestruturado sobre aspectos de saúde, hábitos de vida, familiares e parâmetros socioeconômicos; o Questionário Internacional de Atividade Física (IPAQ – versão curta, para a mensuração de atividade física da última semana); o Questionário de Avaliação da Menopausa (MRS, para quantificar a severidade dos sintomas da menopausa); avaliações antropométricas (estatura, peso, índice de massa corporal – IMC, circunferência abdominal e circunferência do quadril); absorciometria de raios-x de dupla energia (DEXA, para avaliação da composição corporal, estimativas de massa magra e gorda); e a Escala Visual Analógica de Apetite (para quantificação do nível de fome). Amostras sanguíneas foram coletadas para a análise de níveis de hormônios (estradiol e folículo estimulante – FSH) e parâmetros bioquímicos de metabolismo (colesterol total e frações – triglicerídeos, HDL, LDL – e glicemia de jejum). O banco de dados foi digitado e analisado no programa SPSS versão 18.0. Testes univariados (Teste t de Student e de Mann-Whitney) foram aplicados para comparações de médias/medianas entre os grupos, conforme normalidade da variável contínua pelo teste de Shapiro-Wilk. Análises de distribuições (Qui-quadrado com análises de valores residuais ajustados) foram aplicadas para comparações de frequências de variáveis categóricas entre os grupos. Correlações de Spearman foram aplicadas entre todas as variáveis analisadas. O nível de significância adotado para todas as análises foi fixado em 5%. Resultados: Avaliaram-se 114 mulheres, categorizadas em pré-menopausa (n=60), mediana de idade [Intervalo de Confiança – IC95%] de 47,5 [47,01–48,35 anos] e na pós-menopausa (n=54) com mediana de idade de 49 anos [48,29–49,56]. O tempo de pós-menopausa foi (mediana [95%IC] de 1,50[1,63–2,41] anos) e as mulheres na pré-menopausa classificadas como -3b segundo os critérios de STRAW+10. A maioria das participantes apresentava ensino médio ou superior (35,96% e 39,47%, respectivamente), era solteira ou sem parceiro (57,02%), não tabagista (97,37%) e não consumia álcool (57,89%). Quanto ao IMC, foram categorizadas como eutróficas (31,86%) ou obesas (40,71%), sem doença hipertensiva (98,25%), tireoidiana (97,37%) ou cardiovascular (100%). Em relação à atividade física, a maioria das mulheres apresentava nível ativo (51,75%). Na avaliação do apetite, as mulheres na pós-menopausa apresentaram escores maiores do que as prémenopáusicas (p=0,013). Níveis de colesterol total e de HDL foram maiores nas mulheres na pós-menopausa (p=0,040 e p≤0,0001, respectivamente). Não houve diferenças estatísticas entre os grupos quanto à massa corporal total, gordura androide e ginoide, conteúdo mineral ósseo, massa magra, consumo calórico, triglicerídeos e glicemia de jejum (p>0,05). Quanto aos sintomas climatéricos, as mulheres na pósmenopausa apresentaram mais queixas de fogachos e ressecamento vaginal (de moderado a extremamente severo) (p=0,056 e p=0,007, respectivamente) e significância marginal em relação aos problemas sexuais (p=0,086). O IMC, os triglicerídeos séricos e a glicemia de jejum foram positivamente correlacionados à circunferência da cintura, massa corporal, massa adiposa, massa magra e gorduras androides e ginoide. Colesterol HDL foi negativamente relacionado à circunferência da cintura, massa corporal, massa adiposa, massa magra e gordura androide. A escala visual analógica de apetite foi positivamente relacionada a humor deprimido, problemas sexuais e fogachos. Conclusões: Não houve diferenças estatisticamente significativas quanto à massa corporal total, gordura androide e ginoide, conteúdo mineral ósseo, massa magra, consumo calórico, triglicerídeos e glicemia de jejum, possivelmente, porque no início da pós-menopausa as possíveis modificações na composição corporal não sejam impactantes, o que permite considerar esse período como uma janela de oportunidade para intervenções precoces direcionadas ao estilo de vida, prevenindo-se agravos como perfil aterogênico e aumento do risco cardiovascular. / Objetives: To evaluate the effect of menopausal transition on body composition, abdominal fat distribution, body mass index, waist-hip circumference, percentages of android, gynoid and android/gynoid fats ratio, total daily caloric intake and the level of physical activity of climacteric women. Model: A cross-sectional study with climacteric women recruited by electronic and printed media and carried out from March 2014 to October 2015. Place: Clinical Research Center of Clinical Hospital of Porto Alegre (CPC/HCPA), RS/Brazil. Sample: The sample consisted of pre and postmenopausal women aged between 44 and 52 years. Measures of evaluation: The instruments used were: the Executive Summary of the Stages of Reproductive Aging Workshop + 10 (STRAW +10, for the classification of women in relation to menopausal staging); 24- hour food recall (to measure food consumption); a semi-structured questionnaire on aspects of health, life habits, family and socioeconomic parameters; the International Physical Activity Questionnaire (IPAQ – short version, for the measurement of physical activity of the last week); the Menopause Rating Scale (MRS, to quantify the severity of menopausal symptoms), anthropometric assessments (height, weight, body mass index – BMI, waist circumference and hip circumference); Dual-energy x-ray absorptiometry (DXA, to evaluate body composition, estimates of leand and fat mass); and the Visual Analogue Appetite Scale (to quantify the level of hunger). Blood samples were collected for the analysis of female hormone levels (estradiol and follicle-stimulating – FSH) and biochemical parameters of metabolism (total cholesterol and triglyceride fractions – HDL, LDL – and fasting glycemia). The database was entered and analyzed in SPSS version 18.0. Univariate tests (Student’s t test and Mann-Whitney test) were applied for comparisons of means/medians between groups, according to the normality of the continuous variable by the Shapiro-Wilk test. Distribution analyzes (Chi-Square with adjusted residual values) were applied for comparisons of frequencies of categorical variables between the groups. Spearman’s correlations were applied among all analyzed variables. The level of significance adopted for all analyzes was set at 5%. Results: A total of 114 women, pre-menopausal women (n=60) with median age [95% Confidence Interval – CI] of 47.5[47.01–48.35] years and postmenopausal women (n=54) with median age [95%CI] of 49.0[48.29–49.56]. Postmenopausal time median [95%CI] time was of 1.50[1.63–2.41] years and premenopausal women were classified as -3b, according to the STRAW + 10 criteria. The majority of participants had high school education (35.96% and 39.47%, respectively), was single or without partner (57.02%), non-smoker (97.37%) and did not consume alcohol (57.89%). Regarding BMI, they were categorized as either eutrophic (31.86%) or obese (40.71%), without hypertensive (98.25%), thyroid (97.37%) or cardiovascular (100.0%) diseases. In relation to physical activity, the majority of women had an active level (51.75%). In the evalution of appetite, postmenopausal women had higher scores than premenopausal women (p=0.013). Total cholesterol and HDL levels were higher in postmenopausal women (p=0.040 and p≤0.0001, respectively). There were no statistical differences between the groups regarding total body mass, android and gynoid fats, bone mineral content, lean mass, caloric intake, triglycerides and fasting glycemia (p>0.05). Considering the climacteric symptoms, postmenopausal women presented more complaints of hot flashes and vaginal dryness (moderate to extremely severe, p=0.056 and p=0.007, respectively) and marginal significance in relation to sexual problems (p=0.086). BMI, serum triglycerides, and fasting glycemia were positively correlated with waist circumference, body mass, adipose mass, lean mass, android and gynoid fats. HDL cholesterol was negatively related to waist circumference, body mass, adipose mass, lean mass and android fat. The visual analogue scale of appetite was positively related to depressive mood, sexual problems and hot flashes. Conclusions: There were no statistically significant differences in total body mass, android and gynoid fats, bone mineral content, lean mass, caloric intake, triglycerides and fasting glycemia, possible because at the the beginning of postmenopausal period the possible changes in body composition are not impacting, which allows us to consider this period as a time window of opportunity for early interventions directed to lifestyle, preventing ailments such as atherogenic profile.
108

Are Bioelectrical Impedance and Skinfolds Considered Valid Measures for Tracking Body Composition Following Resistance Training when DEXA is the Criterion Measure?

Inglis, J. Greig 01 August 2001 (has links)
The present study was designed to determine if BIA and skinfolds could track changes in body composition like DEXA. Fifty male volunteers participated in a 12-week high-intensity resistance-training program. Body composition was assessed using DEXA, skinfolds (SF), and BIA. Results indicate when DEXA was used as the criterion measure; BIA and SF may not be appropriate assessment techniques. BIA and SF significantly overestimated percent fat and fat-weight pre- and post-treatment (p<0.05). Although SF and BIA exhibited acceptable r-values, significant differences were observed between DEXA and BIA and SF (p < 0.0001). These results indicate that DEXA’s ability to track changes in body composition may be more appropriate compared to BIA and SF during and following a resistance-training program. Future studies using hydrostatic weighing are needed to determine if differences observed are the results of DEXA’s accuracy in tracking fat free-weight or the inability of BIA and skinfolds to track changes.
109

A COMPARISON OF BODY COMPOSITION ESTIMATES BETWEEN THE NORLAND DXA, THE IDXA, AND THE BODPOD® IN OVERWEIGHT TO OBESE ADULTS

Mason, Jalyn 01 January 2019 (has links)
Background: Body composition measures include fat mass (FM), fat free mass (FFM), and percent body fat (%BF), which are markers of health status and disease risk. Accurate body composition assessment is needed to evaluate an individual’s health and the efficacy of treatment strategies. Objective: Compare body composition estimates obtained from the Norland DXA, BodPod®, and iDXA before and after a 12-week exercise intervention. Subjects/setting: Overweight to obese (BMI 25–35 kg/m2) sedentary men and women (n=30) aged 18 to 40 years were recruited from central KY. Main outcome measure: Agreement in FM, FFM, and %BF between Norland DXA, iDXA, and BodPod®. Statistical analysis: Bland Altman plots evaluated mean bias and limits of agreement between iDXA vs Norland DXA, BodPod® vs Norland, and BodPod® vs iDXA. T-tests determined if each mean bias was different from zero. Results: Compared to the iDXA, Norland DXA overestimated BF% and FM at baseline and post intervention (P < 0.01), without differences in FFM (P > 0.05). The BodPod® underestimated BF% and FM and overestimated FFM compared to both DXA machines(all P < 0.01). Conclusion: The Norland and iDXA produce different measures of FM but similar measures of FFM. As well, the BodPod® measures FM and FFM differently than either DXA machine.
110

The Role of TRPM5 in Dietary Fat Preference, Intake, and Body Composition

Minaya, Dulce M. 01 May 2014 (has links)
We recently showed a critical role of Trpm5 in the transduction pathway for long chain polyunsaturated fatty acids. In the present study, I have begun to investigate dietary fat preference and the propensity to develop dietary-induced obesity in Trpm5-/- mice. My preliminary data shows that in male mice placed on a high fat diet, Trpm5-/- mice did not enhance their caloric intake as observed in wild type mice. Most surprisingly, however, was that I did not observe the same differences in between female mice, which posits a potential gender effect of this pathway on dietary fat intake. Also, I show that the preference for dietary fat is not disrupted in Trpm5-/- mice since there is no difference in dietary fat preference between Trpm5-/- and wild type mice. Wild type and Trpm5-/- mice both have a strong preference for the high fat diet, as demonstrated by the fact that they solely consumed the high fat diet. Consistent with our original hypothesis that these responses are specific for high fat feeding, I did not observe any differences in caloric intake in male mice on a high sucrose diet. Again, gender differences were observed, with Trpm5-/- female mice displaying a higher caloric intake than wild type female mice. Furthermore, I used a paired-feeding approach via oral gavage to delve further into whether the effect of Trpm5 disruption was due to pre- or post-ingestive effects. The results from this experiment show that all animals have a reduction in body weight and body fat with no significant difference between wild type and Trpm5-/- mice. This result suggests that the expression of Trpm5 in the oral cavity is necessary for the changes in body weight and composition observed during ad libitum feeding. Also, the fact that Trpm5-/- mice lost body weight and fat mass is contrary to our previous observations. When these animals consume the roughly same number of calories on a high fat diet ad libitum, we observe an increase in body weight and fat mass. This suggests that there might be another mechanism accountable for the response observed in Trpm5-/- mice when fed ad libitum. In conclusion, the results from these experiments suggest a link between dietary fat consumption and development of adiposity.

Page generated in 0.1278 seconds