La balance énergétique (dépense énergétique et ingestion calorique) est au centre du contrôle de la masse corporelle. L’activité physique peut par ailleurs réduire l’appétit et l’ingestion calorique, un phénomène qu’on appelle aussi l’effet anorexigène de l’activité physique. Cependant, l’hormone orexigénique, liée à une diminution de l’appétit, diminue pendant l’exercice pour remonter rapidement après l’effort. Le but de ce mémoire était de déterminer si l’ingestion calorique est réduite quand l’exercice précède immédiatement le repas comparativement à une condition où il y a une pause entre l’exercice et le repas. Pour ce faire, douze garçons non obèses (15-20 ans) ont pris part à l’étude. Chaque participant était évalué individuellement pour les deux tâches suivantes, et ce, dans un ordre aléatoire : 1) Ex = 30 minutes d’exercice (70% VO2max) suivi immédiatement par un buffet à volonté à midi; 2) Expause = 30 minutes d’exercice (70% VO2max) suivi d’une pause de 135 minutes et d’un buffet à volonté à midi. Les visites étaient précédées par un déjeuner standard et complétées avec une collation à volonté durant l’après-midi et un souper type buffet à volonté pour souper. Alors que les résultats ont révélé que la faim était similaire en tout temps, l’ingestion calorique au diner était plus basse pour la condition Ex que pour la condition Expause (5 072 vs 5 718 kJ; p < 0,05). Aucune différence significative n’a été notée pour la collation de l’après-midi et le souper. Chose intéressante, l’ingestion calorique des lipides était plus basse au diner avec une ingestion de 1 604 kJ pour la condition Ex versus 2 085 kJ pour la condition Expause (p < 0,05). Cette étude est la première à investiguer l’effet du positionnement optimal de l’activité physique pour réduire l’ingestion calorique et elle révèle qu’être actif physiquement juste avant le repas joue un rôle sur la diminution de l’ingestion calorique indépendamment des sensations d’appétit. L’absence d’une compensation durant le reste de la journée suggère de plus qu’une balance énergétique négative, incluant une réduction de la consommation de lipides, peut être plus facilement atteinte en positionnant l’activité physique juste avant un repas. / Energy balance (energy expenditure and energy intake) is the central of body weight control. Interestingly, physical activity can suppress appetite and energy intake, a phenomenon also called exercise-induced anorexia. However, orexigenic hormone, which decrease appetite, decreases during exercise to rapidly increase following the effort. Until now, no study has examined the optimal timing of physical activity to maximize this anorexigenic effect and this was the goal of the present thesis. Concretely, this project aimed to determine if energy intake is reduced when exercise immediately precedes the meal compared to a condition in which a pause is present between the exercise and the meal. To do so, twelve non-obese boys (15-20 years old) took part in the study. Each subject was individually evaluated performing the two following tasks in a randomized order: 1) Ex=30-minute exercise bout (70% VO2max) followed immediately by an ad libitum buffet at noon; 2) Expause=30-minute exercise bout (70% VO2max) followed by a 135-minute waiting period and an ad libitum buffet at noon. The visits were preceded by a standardized breakfast and completed with an ad libitum snack in the afternoon and a buffet-type dinner. While results shown that hunger was similar at all times, energy intake at lunch was lower for the Ex condition than for the Expause condition (5,072 vs. 5,718 kJ; p<0.05). No significant difference was noted for the afternoon snack and dinner. Interestingly, caloric intake of fat was lower at lunch, with 1,604 kJ for the Ex condition versus 2,085 kJ for the Ex pause condition (p<0.05). This study is the first to investigate the effect of the timing of physical activity on energy intake, and it reveals that being physically active right before a meal does play a role in energy intake reduction independently of pre-meal appetite sensations. Also, the absence of compensation during the rest of the day suggests that a negative energy balance, including a reduction in lipid consumption, could be more easily obtained by positioning physical activity before a meal.

Background Modern neonatal care has improved the survival rate of extremely preterm infants. These infants are at high risk of malnutrition and growth failure during 3-4 months of hospital care. The objectives of this study was to investigate nutritional intakes during hospitalization and explore associations between nutritional intakes, postnatal growth and retinopathy of prematurity (ROP). Perioperative nutrition in infants undergoing surgery for patent ductus arteriosus (PDA) was also investigated. Methods This is a population-based study of Swedish extremely preterm infants (&lt;27 weeks) born during 2004-2007 (n=602). Detailed data on nutritional supply and anthropometric measurements during hospitalization were retrospectively retrieved from hospital records. Comprehensive data on cohort characteristics, neonatal morbidity and infant mortality were obtained from the Extremely Preterm Infants in Sweden Study (EXPRESS). Results During the first 70 days of life, intakes of energy, protein and several micronutrients, with the exception of iron and some vitamins, were less than estimated requirements, and infants showed severe postnatal growth failure. Energy and protein intake predicted growth in all anthropometric outcomes even when adjusting for severity of illness, and fat intake was positively associated with head growth. Low folate intake was positively correlated with poor weight and length gain while high iron intake, mainly explained by blood transfusions, was negatively associated with poor length gain. Furthermore, a low energy intake was associated with severe ROP (stage 3-5). An increased energy intake of 10 kcal/kg/d was associated with 24% decrease in severe ROP (p=0.01). During the first month, 99% of the infants were exclusively fed human milk. Infants who underwent surgery for PDA (n=140) were malnourished, with energy and macronutrient intakes below minimum estimated requirements before, during and after surgery. Conclusions The severe postnatal growth failure observed in Swedish extremely preterm infants may be prevented by improved intakes of energy, protein, fat and folate and a reduction of the number of blood transfusions. Human milk is the main enteral food source and analyses of human milk macronutrient contents facilitates individualized fortification. Provision of adequate energy intakes during the first four weeks of life may be an effective way to reduce the risk of severe ROP. Perioperative nutrition in infants undergoing PDA surgery needs to be improved. The study results have important implications for nutritional regimens, postnatal growth and health outcome in this new generation of survivors.

Introdução: As doenças cardiovasculares são a principal causa de morte no Brasil. Um dos principais contribuintes para as doenças cardiovasculares é a obesidade, que se apresenta em ascensão no Brasil. A densidade energética da dieta (DED) poderia ser um possível instrumento auxiliar na prevenção do ganho de peso e na avaliação da qualidade geral da dieta, com critérios de cálculo independentes dos hábitos alimentares e procedimento de cálculo mais simples que indicadores de qualidade da dieta. Objetivo: analisar a associação da DED com o risco cardiovascular e averiguar a relação entre DED e índice de qualidade da dieta, em adultos e idosos do município de São Paulo. Métodos: Utilizaram-se dados de participantes do estudo transversal de base populacional denominado Inquérito de Saúde de São Paulo (ISA-Capital - 2008/2009): 357 indivíduos (30 a 74 anos), na análise entre DED e risco cardiovascular, e 941 indivíduos (20 anos ou mais), entre DED e indicador de qualidade da dieta. O recordatório de 24h replicado foi utilizado para aferir o consumo alimentar. A ingestão habitual de alimentos e nutrientes e DED foi estimada pelo Multiple Source Method. A DED foi determinada pelo método foods only, o qual exclui todos alimentos ingeridos na forma de bebidas; a qualidade da dieta, pelo índice de qualidade da dieta revisado (IQD-R), adaptado para a população brasileira, e o risco cardiovascular, a partir de equações preditivas do escore de risco cardiovascular de Framingham. A relação entre a DED e o IQD-R e componentes foi verificada por modelos lineares generalizados, utilizando o modelo gaussiano e a relação entre DED e risco cardiovascular, por modelo de regressão gama, ambos com função de ligação logarítmica. As análises foram realizadas utilizando o módulo survey do Stata, versão 11. Resultados: O valor médio observado da DED, em todas as idades, supera o valor máximo recomendado, pelo World Cancer Research Fund de 1,25kcal/g. A DED apresentou relação significante com o escore de risco em adultos de 45 a 59 anos e em idosos, de 60 a 74 anos, independentemente dos valores de trigliceróis séricos, da energia proveniente de bebidas, categoria de renda familiar per capita e intervalo de tempo entre R24h. Em todas as faixas de idade a ingestão média de fibras, reduziu conforme o aumento de DED, enquanto que as quantidades ingeridas de gorduras totais e trans elevaram-se. A pontuação do IQD-R, bem como da maioria dos seus componentes, foi 7 significativamente menor no maior tercil de DED em relação ao primeiro. Conclusão: A DED apresentou relação positiva significativa com o escore de risco em indivíduos de 45 a 74 anos e com os nutrientes relacionados ao aumento do risco cardiovascular. A relação significativa com o IQD-R, e a maioria dos seus componentes, viabiliza a utilização da DED como um instrumento auxiliar na avaliação da qualidade da dieta. É evidente a necessidade de ações para melhoria da qualidade da alimentação da população estudada, com a finalidade de reduzir a DED apresentada, podendo auxiliar na redução da prevalência da obesidade e mortes por doenças cardiovasculares. / Introduction: Cardiovascular diseases have been the main cause of death in Brazil. Obesity is a major contributor to cardiovascular diseases and it has been increasing in Brazil. The dietary energy density (DED) could be a possible aid tool to weight gain prevents and for assessing the overall quality of the diet, with independent calculation criteria of eating habits and calculation procedures simpler than diet quality indicators. Objective: To analyze the association between DED and cardiovascular risk, and to investigate the relationship between DED and the diet quality index of adults and elderly in the city of São Paulo. Methods: It was used data from participants in the cross-sectional population-based survey entitled Inquérito de Saúde de São Paulo - ISA - Capital 2008/2009: 357 subjects (20-74 years), for analysis between DED and cardiovascular risk , and 941 subjects (20 years or more), for analysis between DED and the diet quality index . The replicated 24-hour recall was used to assess dietary intake. The usual intake of foods, nutrients and DED was calculated by the Multiple Source Method. Caloric and noncaloric beverages were excluded from the calculation of DED (foods only method); the diet quality was analyzed by Brazilian Health Eating Index Revised (BHEI-R), and cardiovascular risk, by predictive equations from the Framingham cardiovascular score risk. As análises foram realizadas utilizando o módulo survey do Stata, versão 11. The relationship between the DED and IQD-R and components was verified by generalized linear models, by gaussian model and the relationship between DED and cardiovascular risk by gamma model, both with log link function. The analyzes were performed using the survey module in Stata, version 11. Results: DED mean exceeded the maximum recommended value of 1.25kcal/g, by World Cancer Research Fund, in all age groups. The DED showed a significant relationship with cardiovascular risk score in 45-59 years-old adults and elderly, independent of serum triglycerides, energy from beverages, category of per capita household income and change of eating habits. The average intake of total fiber decreased with the DED increases, whereas intakes of total fat and trans increased in all category of ages. The BHEI-R score and the scores of most of its components were significantly lower in the highest DED tertile compared with the 9 first. Conclusion: The DED has significant and positive relationship with the Framingham score in 45-74 years-old subjects and the nutrients related to the increase of cardiovascular risk. A significant relationship with BHEI-R, and most of its components, enables the use of DED as an aid instrument in the assessment of diet quality. It is clear the need of actions to improve the quality of the diet in the studied population, in order to reduce the DED, and this could help to decrease the cardiovascular diseases deaths and obesity prevalence.

Introdução: A densidade energética (DE) de alimentos e dietas é apontada como importante fator na regulação do peso corporal e está intimamente relacionada ao consumo energético. Objetivos: Estimar a DE de refeições ofertadas em amostra de empresas inscritas no Programa de Alimentação do Trabalhador (PAT), e analisar a DE da dieta de trabalhadores da cidade de São Paulo e sua associação com características sócio-demográficas. Métodos: A dissertação é composta por dois manuscritos, que analisaram a DE utilizando como métodos de cálculo: a inclusão de todos os alimentos sólidos e das bebidas, excluindo apenas água (DE1); inclusão de todos os alimentos sólidos e bebidas calóricas que contém, no mínimo, 5 kcal/100g (DE2); e a inclusão de todos os alimentos sólidos e exclusão de todas as bebidas (DE3). O primeiro manuscrito avaliou refeições de 21 empresas, pelos métodos DE1 e DE3. Os valores para energia e peso dos alimentos/bebidas foram obtidos pela avaliação do cardápio do almoço em três dias consecutivos. Utilizaram-se testes não-paramétricos nas análises estatísticas. O segundo manuscrito avaliou a dieta de 852 trabalhadores, por meio de recordatório de 24 horas, considerando os três métodos de cálculo da DE. Na análise da relação entre DE e variáveis sócio-demográficas utilizou-se regressão linear. Resultados: Para as refeições oferecidas, a mediana da DE1 foi 1,10 kcal/g e da DE3 foi 1,43 kcal/g. Para a dieta dos trabalhadores, os valores observados foram 1,18 kcal/g (+0,08), 1,22 kcal/g (+0,08) e 1,73 kcal/g (+0,16), considerando os métodos de cálculo DE1, DE2 e DE3, respectivamente. Nos modelos múltiplos de regressão, apenas a variável idade apresentou associação negativa com todos os métodos de DE. Para a DE3, houve incremento da DE para indivíduos não-brancos. Conclusão: Observou-se que a densidade energética das refeições oferecidas pelas empresas estudadas, assim como a dieta dos trabalhadores, em especial dos mais jovens, apresentaram valores elevados. Esses achados sinalizam a necessidade de intervenções nutricionais para promoção de dietas com menor densidade energética, a fim de prevenir a obesidade entre trabalhadores / Introduction: Energy density (ED) of food and diets is considered as an important factor in the regulation of body weight and is intimately tied to energy intake. Aims: To estimate ED of meals offered in a sample of companies enrolled in the Workers Food Program (WFP), and to analyze ED of the diet of workers from the city of São Paulo and its association with socio-demographic characteristics. Methods: The dissertation consists in two manuscripts, which have analyzed ED utilizing as methods of calculation: including all solid food and beverages, excluding water (ED1); including all solid food and beverages containing at least 5 kcal/100g (ED2); including all solid food and excluding all beverages (ED3). The first manuscript evaluated meals from 21 companies, using methods ED1 and ED3. The values for energy and weight of food/beverages were obtaining through the evaluation of the lunch menu during three consecutive days. Non-parametric tests were used for the statistical analyses. The second manuscript evaluated the diet of 852 workers using a 24-hour recall, taking into account the three methods for calculating ED. In the analysis of the relation between ED and socio-demographic variables linear regression was used. Results: For the meals the median of ED1 was 1.10 kcal/g and ED3 1.43 kcal/g. For the workerss diet the ED values observed were 1.18 kcal/g, 1.22 kcal/g and 1.73 kcal/g, considering respectively ED1, ED2, ED3 methods. In the multiple regression models only the age variable was maintained in the final model and showed inverted association with all methods of ED. For ED3 there was an increase of ED for non-white individuals. Conclusion: It was observed that both the energy density of the meals offered by the companies as well as the energy density of the workerss diet, in special the younger ones, showed high values. These findings point out to the necessity of nutritional interventions for promoting diets with lower energy density in order to prevent workerss overweight

O gasto energético total (GET) pode ser usado como medida da ingestão energética (IE). Existe um constante sub-relato da IE obtida por métodos de avaliação do consumo alimentar, mas poucos estudos o investigaram em nações em desenvolvimento. Objetivos: a) comparar a validade das estimativas de IE de um questionário de freqüência alimentar, três recordatórios alimentares e um diário alimentar de três dias, segundo a água duplamente marcada; b) determinar a influência da prática de atividade física, do índice de massa corporal e de fatores psicossociais no sub-relato e; c) comparar as taxas de sub-relato entre agrupamentos de padrões alimentares. Métodos: Sessenta e cinco mulheres responderam aos métodos de inquérito supracitados, a partir dos quais foi estimada a IE. O GET foi medido pela água duplamente marcada. A prática de atividade física, índice de massa corporal, escolaridade, renda, idade, conhecimento nutricional, insatisfação corporal, restrição dietética, compulsão alimentar e o desejo de aceitação social foram correlacionados ao sub-relato. Os padrões alimentares foram obtidos pela análise de cluster. Resultados: O GET foi de 2.622 ± 490 kcal, enquanto que a IE, mensurada respectivamente pelo recordatório, diário e questionário, foi de 2.078 ± 430 kcal; 2.044 ± 479 kcal e 1.984 ± 832 kcal. A proporção de sub-relatores foi de 24,6% para o recordatório, 29,2% para o diário e 53,8% para o questionário (p < 0,005). Os sub-relatores apresentaram menores médias de renda e escolaridade e maiores valores de idade, insatisfação corporal e desejo de aceitação social. O sub-relato foi mais comum no padrão alimentar mais frugal. Conclusão: Os três métodos de avaliação do consumo alimentar apresentaram erros sistemáticos, embora o questionário de freqüência alimentar tenha tido o pior desempenho. O sub-relato foi influenciado por diversos fatores psicossociais e variou conforme o padrão alimentar relatado, o que pode comprometer a avaliação do consumo / Total energy expenditure (TEE) may be used as a measure of energy intake (EI). There is a constant underreporting of EI obtained by dietary assessment methods, but few studies have investigated it in developing nations. Objectives: a) to compare the validity of EI estimates obtained by a food-frequency questionnaire, three diet recalls and a three-day food record; b) to determine the influence of physical activity, body mass index and psychosocial factors on underreporting and; c) to compare underreporting rates between dietary pattern\'s clusters. Methods: Sixty-five women completed the dietary assessment methods, which were used to estimate EI. TEE was measured by doubly labeled water. Physical activity practice, body mass index, education, income, age, nutritional knowledge, body dissatisfaction, dietary restraint, binge eating and social desirability were correlated to underreporting. Dietary patterns were obtained by cluster analysis. Results: TEE was 2,622 ± 490 kcal, while EI, measured respectively by the diet recall, food record and food-frequency questionnaire, was 2,078 ± 430 kcal; 2,044 ± 479 kcal and 1,984 ± 832 kcal. Proportion of underreporters was 24.6% (recall), 29.2% (record) and 53.8% (questionnaire) (p < 0.005). Underreporters had smaller income and education and greater age, body dissatisfaction and social desirability. Underreporting was more common in the \'frugal foods\' pattern. Conclusions: The three dietary assessment methods presented systematic errors, although the foodfrequency questionnaire had the worst performance. Underreporting was influenced by psychosocial factors and varied according the reported dietary pattern, which may compromise dietary assessment

<p>Low calorie sweeteners (LCS) provide sweetness with little to no energy. Each sweetener has a unique chemical structure that possesses unique sensory and functional characteristics. While LCS are generally considered in aggregate, these unique chemical structures have potential implications for sensory, metabolic, and behavioral differences that may impact body weight and glycemia. Therefore, two, twelve-week experiments were conducted to determine the effect of chronic LCS consumption on body weight, glycemia, and ingestive behaviors. </p> <p>The first experiment investigated the differential effects of four LCS (saccharin, aspartame, rebaudioside A, and sucralose) and sucrose consumed for twelve weeks on body weight, glycemia, and ingestive behaviors among healthy adults with overweight or obesity (body mass index (BMI) between 25 and 40 kg/m²). In a parallel-arm design, 154 participants were randomly assigned to consume 1.25 to 1.75L of beverage sweetened with 1 of the 5 sweeteners daily for 12 weeks. Body weight was measured every two weeks; energy intake, energy expenditure, and appetite were assessed every 4 weeks; and glucose tolerance was measured at baseline and week 12. Every four weeks, participants completed 24-hour urine collections to determine study compliance via PABA excretion. Sucrose and saccharin consumption led to increased body weight across the 12-week intervention (Δ weight = +1.85 and +1.18kg, p ≤ 0.02) and did not differ from each other. While there was no significant change in body weight with consumption of the other LCS treatments compared to baseline, changes in weight in comparison to the sucrose treatment (sucrose – LCS) were significantly different for aspartame, rebA, and sucralose after 12 weeks (weight difference = 1.13, 1.25, 2.63kg, respectively; p ≤ 0.03). In addition, change in body weight at week 12 was significantly lower between sucralose and all other LCS (weight difference ≥ - 1.37 kg, p=0.008).</p> <p>The second experiment investigated the effect of daily aspartame ingestion on glycemia, body weight, and appetite. One hundred lean (BMI between 18 and 25 kg/m²) adults were randomly assigned to consume 0, 350, or 1050 mg aspartame/day for twelve weeks in a parallel-arm design. This experiment followed a similar protocol but measured body weight and blood pressure weekly and contained a 240-min glucose-tolerance test (OGTT) with measurements of selected hormones at baseline and week 12. Participants also collected 24-h urine samples every four weeks. There were no group differences for glucose, insulin, resting leptin, glucagon-like peptide 1, or gastric inhibitory peptide at baseline or week 12. There also were no effects of aspartame ingestion on appetite, body weight, or body composition. </p> <p>These trials demonstrate that all LCS contribute negligible energy but should not be aggregated because of their differing effects on body weight. Sucrose and saccharin consumption significantly increased body weight compared to aspartame, rebA, and sucralose. This differential change in body weight among LCS indicates individual LCS likely exert different physiological responses beyond the contribution of sweetness with negligible energy. Saccharin, rebA, sucralose, and aspartame (ingested at three doses) for twelve weeks had no effect on glycemia. These data do not support the view that LCS are problematic for the management of glycemia. If substantiated through additional testing, findings from this trial have implications for consumers, food industry, clinicians, and policy makers. Some LCS may not hold the anticipated beneficial effects on body weight (e.g., saccharin) and positive effects of one LCS (sucralose) may be attenuated if combined with select other LCS. Going forward it will be important to consider each LCS as a distinct entity with respect to its potential health effects.</p>

Introdução: A densidade energética (DE) de alimentos e dietas é apontada como importante fator na regulação do peso corporal e está intimamente relacionada ao consumo energético. Objetivos: Estimar a DE de refeições ofertadas em amostra de empresas inscritas no Programa de Alimentação do Trabalhador (PAT), e analisar a DE da dieta de trabalhadores da cidade de São Paulo e sua associação com características sócio-demográficas. Métodos: A dissertação é composta por dois manuscritos, que analisaram a DE utilizando como métodos de cálculo: a inclusão de todos os alimentos sólidos e das bebidas, excluindo apenas água (DE1); inclusão de todos os alimentos sólidos e bebidas calóricas que contém, no mínimo, 5 kcal/100g (DE2); e a inclusão de todos os alimentos sólidos e exclusão de todas as bebidas (DE3). O primeiro manuscrito avaliou refeições de 21 empresas, pelos métodos DE1 e DE3. Os valores para energia e peso dos alimentos/bebidas foram obtidos pela avaliação do cardápio do almoço em três dias consecutivos. Utilizaram-se testes não-paramétricos nas análises estatísticas. O segundo manuscrito avaliou a dieta de 852 trabalhadores, por meio de recordatório de 24 horas, considerando os três métodos de cálculo da DE. Na análise da relação entre DE e variáveis sócio-demográficas utilizou-se regressão linear. Resultados: Para as refeições oferecidas, a mediana da DE1 foi 1,10 kcal/g e da DE3 foi 1,43 kcal/g. Para a dieta dos trabalhadores, os valores observados foram 1,18 kcal/g (+0,08), 1,22 kcal/g (+0,08) e 1,73 kcal/g (+0,16), considerando os métodos de cálculo DE1, DE2 e DE3, respectivamente. Nos modelos múltiplos de regressão, apenas a variável idade apresentou associação negativa com todos os métodos de DE. Para a DE3, houve incremento da DE para indivíduos não-brancos. Conclusão: Observou-se que a densidade energética das refeições oferecidas pelas empresas estudadas, assim como a dieta dos trabalhadores, em especial dos mais jovens, apresentaram valores elevados. Esses achados sinalizam a necessidade de intervenções nutricionais para promoção de dietas com menor densidade energética, a fim de prevenir a obesidade entre trabalhadores / Introduction: Energy density (ED) of food and diets is considered as an important factor in the regulation of body weight and is intimately tied to energy intake. Aims: To estimate ED of meals offered in a sample of companies enrolled in the Workers Food Program (WFP), and to analyze ED of the diet of workers from the city of São Paulo and its association with socio-demographic characteristics. Methods: The dissertation consists in two manuscripts, which have analyzed ED utilizing as methods of calculation: including all solid food and beverages, excluding water (ED1); including all solid food and beverages containing at least 5 kcal/100g (ED2); including all solid food and excluding all beverages (ED3). The first manuscript evaluated meals from 21 companies, using methods ED1 and ED3. The values for energy and weight of food/beverages were obtaining through the evaluation of the lunch menu during three consecutive days. Non-parametric tests were used for the statistical analyses. The second manuscript evaluated the diet of 852 workers using a 24-hour recall, taking into account the three methods for calculating ED. In the analysis of the relation between ED and socio-demographic variables linear regression was used. Results: For the meals the median of ED1 was 1.10 kcal/g and ED3 1.43 kcal/g. For the workerss diet the ED values observed were 1.18 kcal/g, 1.22 kcal/g and 1.73 kcal/g, considering respectively ED1, ED2, ED3 methods. In the multiple regression models only the age variable was maintained in the final model and showed inverted association with all methods of ED. For ED3 there was an increase of ED for non-white individuals. Conclusion: It was observed that both the energy density of the meals offered by the companies as well as the energy density of the workerss diet, in special the younger ones, showed high values. These findings point out to the necessity of nutritional interventions for promoting diets with lower energy density in order to prevent workerss overweight

La production endogène ou la prise exogène d’hormones sexuelles chez la femme génère un climat hormonal qui lui est propre. Ces particularités endocriniennes influent sur la composition corporelle et modifient les sécrétions et/ou la sensibilité de certaines hormones clés du métabolisme énergétique pouvant conduire à une utilisation spécifique des substrats énergétiques à l’exercice. L’objectif de ce travail était d’étudier l’influence d’une contraception orale (CO : mini dosée monophasique), de la prise alimentaire pré-exercice et de la localisation des graisses sur les réponses métaboliques et hormonales de la femme préménopausée et normo-pondérée à l’exercice (45 min à 65% de O2max). Nos résultats ont montré que la prise d’une CO ne modifiait pas les réponses métaboliques et hormonales et l’utilisation des substrats énergétiques à l’exercice quel que soit le statut nutritionnel des sujets (exercice à jeun ou en situation postprandiale). Cependant, à l’exercice, une situation de jeûne a favorisé une augmentation de l’oxydation lipidique et cela quel que soit le statut hormonal des sujets (CO+ ou CO-). En situation postprandiale, l’exercice physique a stimulé l’activité lipolytique chez des femmes CO+ et CO- sans distinction entre les deux groupes. Enfin, quand l’utilisation des substrats énergétiques à l’exercice est appréhendée en fonction du rapport de la masse grasse abdominale/masse grasse des membres inférieurs (A/MI), nos travaux ont montré une augmentation de la mobilisation et de l’oxydation des lipides chez les femmes présentant un plus faible rapport A/MI (malgré des masses corporelles et des tours de taille normaux). Ainsi, au sein d’une population féminine normo-pondérée, les CO minidosées monophasiques ne semblent pas influer sur l’utilisation des substrats énergétiques à l’exercice, alors que la prise alimentaire pré-exercice et la localisation des graisses semblent avoir un impact plus important sur le métabolisme énergétique à l’exercice. / In the female population, sexual hormones (endogen production or exogenous consumption) induce particular hormonal status leading to specific body composition and metabolic and hormonal responses at rest and during exercise. The aim of this work was to determine the influence of oral contraception (low dose monophasic combined OC), pre-exercise food intake and body fat mass localization on metabolic and hormonal responses during exercise (45 min at 65% of O2max) in normal weight premenopausal women. Our results showed that OC did not alter substrate mobilization and oxidation during exercise (in fast and postprandial conditions). However, during exercise performed in fast condition, women exhibited greater lipid oxidation rates whatever their hormonal status (OC+ vs OC-). In postprandial condition, exercise increased lipolytic activity in OC+ and OC- women without differences between both groups. Finally, it has been observed that abdominal to lower body (A/LB) fat mass ratio influenced substrate mobilization and oxidation in premenopausal women with normal weights and waist circumferences. Subjects with a lower ratio exhibited greater lipid mobilization and oxidation than those with a higher ratio. Therefore, in normal weight women, low dose monophasic combined OC do not appear to influence substrate oxidation whereas pre-exercise food intake and body fat mass localization may have an important impact on substrate metabolism during exercise.

Diss. (sammanfattning) Linköping : Univ., 2005. / Härtill 4 uppsatser.

No description available.