Collegiate and elite female athletes have been identified as a subpopulation at heightened risk for disordered eating and pathogenic weight management practices. It was hypothesized that this increases risk may be related to sport specific pressures (such as team conducted weigh-ins), or the use and frequency of self-weighing. It appears that mandatory, team conducted weigh-ins are not salient to female athletes in regards to experiencing internalization, body image concerns, dietary restraint, negative affect, and bulimic symptomatology. Results, however, indicate that frequency of engagement in self-weighing may be influential in the engagement of disordered eating symptoms. Specifically, athletes who weighed themselves three or more times per week reported significantly more internalization of general societal ideals and athletic body ideals. For body image concerns, athletes who weighed three or more times per week reported being more concerned with their body size/shape than all others. With respect to dietary behaviors, athletes who weighed themselves three or more times per week reported engaging in significantly more caloric restriction than did those who weighed less frequently. For negative affect, the athletes who weighed themselves three or more times per week reported significantly higher levels of both anger and guilt. Finally for bulimic symptomatology, athletes who weighed themselves three or more times a week had significantly higher levels than those who weighed once or twice or not at all.

Cette étude porte sur une intervention de groupe basée sur la thérapie cognitivo-comportementale pour l’hyperphagie boulimique (HB), dont les effets potentiels sur la qualité de vie reliée au poids, la fréquence et la sévérité des crises de boulimie, les symptômes dépressifs, l’image corporelle et le poids corporel ont été mesurés, et le degré d’acceptation par les participantes a été documenté. Ainsi, 11 femmes avec un surplus de poids et répondant aux critères diagnostiques de l’HB ont été recrutées du printemps 2012 à l’hiver 2013, dans la région de Montréal. Le programme comportant huit séances hebdomadaires était dispensé par une nutritionniste et une psychothérapeute. La qualité de vie reliée au poids (Impact of Weight on Quality of Life), la fréquence des crises de boulimie (rappel des sept derniers jours), la sévérité des crises de boulimie (Binge Eating Scale), les symptômes dépressifs (Inventaire de Beck pour la dépression), l’insatisfaction corporelle (Body Shape Questionnaire) et le poids corporel ont été mesurés avant et à la fin de l’intervention. Puis, un questionnaire pour mesurer l’acceptation par les participantes était soumis au terme du programme. Le taux de participation aux séances était aussi colligé. Les résultats montrent que notre programme a permis une amélioration significative du score global de la qualité de vie reliée au poids de 8,4 ± 13,3, ainsi qu’en termes d’estime de soi et de travail. Aussi, une diminution significative de la fréquence des crises de boulimie de 2,1 ± 2,1 jours, de la sévérité des crises de boulimie dont le score a diminué de 10,9 ± 7,7, des symptômes dépressifs dont le score a diminué de 8,3 ± 5,7 et de l’insatisfaction corporelle dont le score a diminué de 32,8 ± 17,1, ont été observées. Toutefois, il n’y a pas eu de perte de poids au terme de l’intervention. Puis, le programme a été bien accepté par les participantes tel que démontré par le taux de participation aux séances de 93,8 % et la satisfaction mesurée par l’appréciation des divers éléments du programme de 4,6 sur 5 et la pertinence de ceux-ci de 4,8 sur 5. Ces données suggèrent que l’intervention de groupe semble être prometteuse pour améliorer les symptômes et conséquences de l’HB, à l’exception du poids. / This study focuses on a group intervention for binge eating disorder (BED), by measuring its potential effects on the quality of life related to weight, frequency and severity of binge episodes, depressive symptoms, body dissatisfaction and body weight, and documenting the degree of acceptance of the intervention by the participants. Thus, 11 overweight women that met the BED diagnostic criteria were recruited from spring 2012 to winter 2013, in Montreal. The program includes eight weekly sessions based on Cognitive Behavioral Therapy provided by a nutritionist and a psychotherapist. Quality of life related to weight (Impact of Weight on Quality of Life), binge eating frequency (recall of the last seven days), binge eating severity (Binge Eating Scale), depression (Beck Inventory for depression), body dissatisfaction (Body Shape Questionnaire) and body weight were measured before and after the intervention. Then, a questionnaire to assess the acceptance by the participants was submitted at the end of the program. The rate of participation was also collected. The results showed that our program has resulted in significant improvements in the overall quality of life score related to weight of 8.4 ± 13.3, and in terms of self-esteem and work. We also observed a decrease in binge eating frequency by 2.1 ± 2.1 days as well as in binge eating severity, depressive symptoms and body dissatisfaction whose scores decreased by 10.9 ± 7.7, 8.3 ± 5.7 and 32.8 ± 17.1 respectively. However, there was no significant difference in weight at the end of the intervention. Also, the program was well accepted by the participants with a participation rate of 93.8%. Satisfaction and relevance of the program scored respectively 4,6 and 4,8 out of 5. These data suggest that the group intervention seems to be a promising method to improve the symptoms and consequences of HB, except for weight.

Title: Lifestyle changes to lifestyle modification for people with multiple sclerosis Aim: Designing a program that affects lifestyle, fitness and physiological parameters in subjects of different age and different sex of people who have a diagnosis of multiple sclerosis (MS). Method: A literary review to make a summary of knowledge on MS and use of physical activities as opportunities to influence the overall lifestyle of people with MS. Results: The result is an overview of the programs and its evaluation - changes in physiological parameters, condition and subjective feelings. We found that when respecting the state of health programs may be implemented in the long term. Conclusion: The success of interventions depends on collaboration, time availability, but also the respecting of the designed programs of people involved. At the same time, however, assumes that an active lifestyle affects the mental aspect of individuals and their subjective feelings. Keywords: Multiple sclerosis, physical condition, subjective feelings, body fat percentage, body water percentage, body weight, muscle dysbalance

Les PBDEs appartiennent à la famille des retardateurs de flamme bromés, substances massivement utilisés ces dernières décennies. Ces molécules sont aujourd’hui retrouvées de façon ubiquitaire dans l’environnement extérieur et intérieur. L’Homme est exposé à ces polluants par le biais de l’alimentation et de l’ingestion/inhalation de poussières ménagères ou industrielles contaminées. Leurs propriétés lipophiles et leur persistance sont à l’origine de leur bioaccumulation dans les matrices abiotiques et biologiques (lait, sérum…). Les travaux de recherche de cette thèse ont eu pour objectif d’évaluer l’impact d’une exposition à un polluant environnemental toxique et très répandu, le BDE-99, administré dans des conditions reflétant l’exposition humaine. Ainsi, les effets d’une administration de longue durée à des doses réalistes de BDE-99 (0,15, 1,5 et 15 µg/kg/j) ont été évalués au plan neurocomportemental et physiologique chez le rat mâle de souche Sprague-Dawley. Aucune altération de l’activité, de l’anxiété et des fonctions cognitives n’a été mise en évidence que les animaux aient été traités à l’âge adulte, à partir du sevrage ou à partir du 8ème jour de vie postnatale. Les seules variations comportementales significatives observées ont été des troubles transitoires de la coordination locomotrice ainsi qu’un retard d’une journée de l’ouverture des yeux chez les animaux traités avec le BDE-99 depuis l’âge de 8 jours. Au plan physiologique, aucune variation significative de l’évolution pondérale, des prises hydrique et alimentaire ainsi que du poids de plusieurs organes (foie, cerveau, reins, rate et thymus) n’a été observée quelle que soit la dose de BDE-99 administrée et la période d’exposition considérée. Ces résultats montrent donc que ce polluant administré chez le rat à des doses réalistes, reflétant celles auxquelles l’Homme est réellement exposé, n’est pas à même d’induire une toxicité neurocomportementale que les animaux aient contaminés à l’âge adulte ou bien lors de différentes phases du développement postnatal. Le fait d’avoir utilisé des doses correspondantes au niveau d’exposition environnemental est sans aucun doute à la base des discordances observées entre les résultats de ce travail et ceux des études publiées par ailleurs, soulignant ainsi la nécessité de réaliser des modèles d’exposition les plus pertinents possibles de la réalité humaine pour pouvoir conclure au mieux quant au risque lié à cette famille de contaminants pour la santé humaine. / PBDEs belong to flame retardants, substances heavily used in recent decades. These molecules are now found ubiquitously in the environment outside and inside. Humans are exposed to these pollutants through diet and ingestion/inhalation of household dust or contaminated industrial dust. Their lipophilic properties and their persistence are the cause of their bioaccumulation in abiotic and biological matrices (milk, serum ...). The research works of this thesis was aimed to assess the impact of exposure to a toxic environmental pollutant and very prevalent, BDE-99, administered in conditions reflecting the human exposure. Thus, the effects of long-term exposure to realistic doses of BDE-99 (0.15, 1.5 and 15 µg/kg/day) were evaluated in terms neurobehavioral and physiological in male Sprague-Dawley rats. No alteration of the activity, anxiety and cognitive function has been highlighted that the animals were treated in adulthood, from weaning or from the 8th day of postnatal life. The only significant behavioral variations observed were transient locomotor coordination disorders and a delay of one day of eye opening in animals treated with BDE-99 from the age of 8 days. On a physiological level, no significant variation in body weight change, food and water consumption and weight of several organs (liver, brain, kidneys, spleen and thymus) was observed whatever the dose of BDE-99 administered and the exposure period considered. These results show that this pollutant administered to rats at realistic doses, reflecting those to which humans are actually exposed, is not able to induce neurobehavioral toxicity that the animal are contaminated in adulthood or at different phases of postnatal development. The fact to have used corresponding the level of environmental exposure is undoubtedly the basis of discrepancies observed between the results of this work and those of the published studies elsewhere, underscoring the necessity to realize exposure models the most possible relevant in order to able to conclude at best about risk associated with this family of contaminants to human health.

9 Abstract Aim of the study. In mammals, including humans, the dominance of maternal influence on fetal size is manifesting. The main known limits from non-genetic components causing the physiological variation of the birth weight are maternal skeletal dimensions (body height and weight) and parity. The main aim of our study is to analyze the relationships between maternal height, maternal weight at the beginning and at the end of gravidity, and anthropometric parameters of a newborn. Data and Methods. Our study is based on transversal anthropometric data of 201 newborns (92 boys, 109 girls) born in Regional Hospital Kladno during one year (from September 2010 till August 2011), and their mothers. In one set of newborns (n = 156) 24 different body sizes were measured in detail. In the second group (n = 45) only birth weight, birth length and head circumference of the newborn were registered. Somatic characteristic of mothers were gathered by questionnaire. Results. The average value of the birth weight of newborns (boys: x = 3 318 g, girls: x = 3 232 g), maternal height ( x = 167,3 cm) and maternal pregravid weight ( x = 64,7 kg) correspond to the reference values. The maternal average age is 29,9 years. Statistically significant dependence can be seen between the birth weight and birth length of a newborn...

Aim: To examine the relationship between reported vigorous physical activity (VPA) and body mass index (BMI) in children (6–7 years) and adolescents (13–14 years). Methods: In the International Study of Asthma and Allergies in Childhood Phase Three, 75 895 children's parents and 199 502 adolescents answered questions relating to VPA, height and weight. The association between VPA and BMI was analysed using general linear models, adjusting for country gross national index. Results: Compared to children who undertook no VPA, those in the infrequent group (once or twice per week) and those in the frequent group (three or more times per week) had mean (95% CI) BMI values 0.07 kg/m 2 (0.03–0.11) and 0.09 kg/m 2 (0.03–0.15) greater, respectively (p = 0.001). Compared to adolescents reporting no VPA, those in the infrequent group had a BMI 0.19 kg/m 2 (0.15–0.23) greater while those in the frequent group had a BMI 0.01 kg/m 2 (−0.03–0.05) greater (p < 0.0001). Conclusion: Reported VPA is not associated with lower BMI among children and adolescents. Investigation of VPA and BMI may be best undertaken in conjunction with other variables in the energy expenditure equation. A focus on VPA alone may be an inefficient way to manage BMI. / Revisión por pares

Introdução: O nascimento de recém-nascidos pré-termo tardios (RNPT-T), geralmente tratados como \"quase termo\", vem aumentando nas últimas décadas. Vários fatores são atríbuídos à sua etiologia e contribuem para aumentar as taxas de morbimortalidade perinatal e infantil. Atualmente se dispõe de poucos estudos sobre esses recém-nascidos, especialmente sobre o seu crescimento. Objetivos: Analisar o crescimento de RNPT-T nos seis primeiros meses de idade corrigida. Métodos: Estudo observacional, analítico de uma coorte de 64 RNPT-T, coletados nos quatro maiores hospitais de Cuiabá, entre janeiro e setembro de 2013 e acompanhados até 6 meses de idade corrigida. Os dados foram coletados ao nascer, às 40 semanas, 3 e 6 meses de idade corrigida. Foram realizadas análises de correlação entre os parâmetros antropométricos perímetro braquial (PB) e prega cutânea tricipital (PCT) em função dos índices antropométricos PB/PC (perímetro cefálico), peso/comprimento (P/C) e Índice de Massa Corpórea (IMC) e realizada regressão linear múltipla. Resultados: Ao nascimento, 81,3% foram classificados como adequados para a idade gestacional, com a média de peso de 2343,80g ± 430,50. Todos os recém-nascidos apresentaram crescimento contínuo nos seis meses de idade corrigida para os valores de peso, comprimento e perímetro cefálico (PC). Já os valores médios de PCT, de PB/PC e de IMC não mostraram diferença aos 6 meses de idade corrigida. Todos os coeficientes de correlação (r) dos parâmetros PCT e PB em relação aos índices antropométricos apresentaram significância estatística, sendo os valores mais altos para PB versus PB/PC e P/C e menores para PB versus IMC. No modelo final da regressão linear múltipla da PCT, o PB/PC contribuiu significantemente para predizer o depósito de gordura ao nascimento, às 40 semanas e aos 3 meses de idade corrigida (33,8%%, 46,07% e 18,08% respectivamente); aos 6 meses o melhor preditor foi a razão P/C (10,45%). O melhor preditor para o PB foi o PB/PC, que permaneceu no modelo com valores de 73,71%% em todos os tempos avaliados. Conclusão: Os parâmetros peso, comprimento, perímetro cefálico e perímetro braquial e a relação P/C aumentaram nos quatro tempos de aferição, enquanto o PCT e as relações PB/PC e IMC não se modificaram do primeiro para o segundo trimestre e o PB/PC foi o melhor preditor do depósito de gordura subcutânea tricipital (PCT) e de massa gorda e muscular (PB) / Introduction: The birth of newborns late preterm (RNPT -T), usually treated as \"near term\", has been increasing in recent decades. Several factors are attributed to its etiology and contribute to increased rates of perinatal and infant morbidity and mortality. Currently there are few studies of these newborns, especially about their growth. Objectives: To analyze the growth pattern of late preterm infants from birth to six months of corrected age. Methods: This cohort study included 64 RNPT-T, in four major hospitals in Cuiabá, between January and September 2013 and followed until 6 months corrected age. Data were collected at birth, at 40 weeks, 3 and 6 months corrected age. Correlation analyzes between anthropometric parameters mid- arm circumference (MAC) and triceps skinfold (TS) on the basis of anthropometric indices MAC / HC (head circumference), weight / length (W / L) and body mass index (BMI) were performed multiple linear regression. Results: At birth, 81.3 % were classified as appropriate for gestational age, with the average weight of 2343.80 ± 430.50 g. All newborns had a continuous growth in the six months corrected age for the values of weight, length and head circumference (HC). The average value of TS values of MAC / HC and BMI showed no difference at 6 months of corrected age. All correlation coefficients (r) of the TS and MAC parameters in relation to anthropometric indices showed statistically significant, with the highest values for MAC versus MAC / HC and W / L and lower for MAC versus BMI. At the end of the TS model of multiple linear regression, the MAC / HC contributed significantly to predict the deposition of fat at birth, at 40 weeks and at 3 months\' corrected age (33.8 %, 46.07 % and 18.08 % respectively); at 6 months was the best predictor of the ratio W/ L (10.45%). The best predictor for the MAC was the MAC / HC, which remained in the model with values of 73.71 % at all evaluated times. Conclusion: The parameters weight, length, head circumference and arm - circumference and the ratio W / L increased in the four times of measurement, while the TS and MUAC / HC relations and BMI did not change from the first to the second quarter and MAC / HC was the best predictor of subcutaneous fat deposit triceps (TS) and fat and muscle (MAC) mass

Foi comparada a massa óssea e a composição corporal dos hemicorpos dominante e não dominante de um grupo (A) de 16 pessoas com paralisia cerebral com hemiplegia espástica, e de um grupo (B) de 29 voluntários normais por meio da mensuração da massa corporal, estatura e densitometria óssea do corpo total com composição corporal. Foi encontrada diferença estatística significante no conteúdo mineral ósseo dos membros superiores do grupo A e dos membros superiores e inferiores, tronco e total do grupo B; na massa magra dos membros inferiores do grupo A e dos membros superiores e inferiores, tronco e total do grupo B; na massa adiposa dos membros inferiores do grupo A e dos membros superiores e inferiores, tronco e total do grupo B; e no conteúdo mineral ósseo dos membros superiores e inferiores, e total e na massa magra dos membros superiores e inferiores entre os hemicorpos não dominantes dos grupos A e B. Foi encontrada também correlação estatística significante entre o conteúdo mineral ósseo e a massa magra nos grupos A e B em todos os sítios, exceto no tronco dominante do grupo A; e o conteúdo mineral ósseo e a massa corpórea no tronco dominante do grupo A e no membro inferior dominante e bilateral do grupo B / Were compared the bone mass and body composition of the dominant and nondominant hemi bodies in a group (A) of a 16 spastic hemiplegic cerebral palsy and in a group (B) of 27 normal volunteers by weight, height, and densitometry of total body with body composition measure. Were observed significant statistical difference in the bone content mineral of the upper limbs of the group A and of the upper and lower limbs, trunk and total of the group B; in the lean mass of the lower limbs of the group A and of the upper and lower limbs, trunk and total of the group B; in the mass fat of the lower limbs of the group A and of the upper and lower limbs, trunk and total of the group B; and in the bone mineral content of the upper and lower limbs, and total, and in the lean mass of the upper and lower limbs between the hemi bodies no dominant of the A and B groups. Were observed too statistical correlation between the bone mineral content and lean mass in the groups A and B in all locals, except in the trunk of group A; and between the bone mineral content and body mass in the trunk of group A and lower limb dominant and bilateral of group B

Durante a vida intrauterina, o desenvolvimento do embrião e do feto é suscetível a mudanças ambientais que podem alterar o fenótipo do indivíduo na vida pós-natal. Eventos que ocorrem durante períodos críticos de rápida divisão celular, nos quais são formados os diversos órgãos e tecidos, podem alterar a estrutura e função de sistemas orgânicos gerando consequências precoces (baixo peso ao nascimento) e tardias (doenças na vida adulta). Os protocolos experimentais da maior parte dos estudos sobre a programação fetal reduz o tamanho da ninhada logo após o nascimento. Essa abordagem dificulta a interpretação e reprodutibilidade dos resultados observados. O objetivo deste estudo foi determinar se a pressão sanguínea, o metabolismo de carboidratos e gasto energético em proles adultas é influenciado pelo tamanho da ninhada. Ratas Wistar foram alimentadas com ração padrão ad libitum e foram acasaladas com ratos machos com 12 semanas de idade. Após o nascimento, a prole foi dividida em três grupos: tamanho da ninhada sem redução (Gc), proles reduzido a oito filhotes (G8) e proles reduzidos a quatro filhotes (G4). Ao fim de 12 semanas de idade, o peso corporal, pressão arterial, consumo de ração, glicemia, insulina, colesterol e triacilgliceróis, massa de tecido adiposo marrom, índice de adiposidade, massa renal e cardíaca foram determinados. O peso corporal, índice de adiposidade, glicemia, nível de insulina e índice HOMA foram maiores em machos e fêmeas no grupo G4 do que nos grupos G8 e Gc. No entanto, o consumo de ração foi menor no grupo G4. A pressão arterial foi maior no grupo Gc em machos e fêmeas. Em resumo, a redução do tamanho da ninhada está relacionada com a obesidade, resistência à insulina e possíveis alterações no gasto energético na prole adulta / During intrauterine life, the developing fetus is susceptible to environmental changes that can alter the phenotype of the individual in postnatal life. This phenomenon is called fetal programming. Events that occur during critical periods of rapid cell division may alter the structure and function of organ systems, resulting in consequences both early (low birth weight) and late (diseases in adulthood) in life. The experimental protocols of most of the studies on fetal programming involve a reduction in litter size soon after birth. This approach hampers the interpretation and reproducibility of the observed results. The purpose of this investigation was to determine if blood pressure, carbohydrate metabolism and energy expenditure in adult offspring are influenced by litter size. Female Wistar rats were fed standard rat chow ad libitum and were mated with male rats at 12 weeks of age. After birth, the offspring were divided into three groups: unchanged litter size (GU), culled to eight neonates (G8) and culled to four neonates (G4). At 12 weeks of age, the body weight; blood pressure; food intake; glucose, insulin, cholesterol and triacylglycerol levels; brown adipose tissue mass; adiposity index; renal mass; and cardiac mass were determined. The body weight, adiposity index, glucose level, insulin level and HOMA index were higher in males and females in the G4 group than in the G8 and GU groups. However, food consumption was lower in G4 males. The blood pressure was higher in the GU group. In summary, a small litter size is related to obesity, possible alterations in energy expenditure and insulin resistance in adult offspring

O objetivo deste trabalho foi avaliar o efeito do uso de volumosos com valor nutricional distinto sobre as exigências e a eficiência de uso da energia e da proteína por ovinos ½ Dorper × ½ Santa Inês, em crescimento. Para isso, 84 cordeiros, machos não castrados, foram desmamados aos 56 dias de idade (PV inicial = 18,0 ± 3,3 kg) e confinados em baias individuais, sendo distribuídos em dois grupos: VBVN cordeiros alimentados com dieta composta por volumoso de baixo valor nutricional (bagaço de cana in natura); e VAVN cordeiros alimentados com dieta composta por volumoso de alto valor nutricional (feno de coastcross). Destes, sete animais de cada grupo foram aleatoriamente selecionados e abatidos após um período de adaptação de 10 dias (animais referência). Dentre os remanescentes, 21 animais de cada grupo foram alimentados ad libitum e abatidos aos 25, 35 ou 45 kg de peso vivo (sete animais por grupo) sendo, os 28 demais animais, submetidos a dois níveis de restrição alimentar, de forma a obterem-se diferentes níveis de consumo de energia metabolizável (EM): 70 e 50% do consumo ad libitum. Foram determinadas as concentrações e as retenções corporais de gordura, nitrogênio e energia. Adicionalmente, seis animais ½ Dorper × ½ Santa Inês (PV médio = 52,3 ± 6,9 kg), machos não castrados canulados no rúmen, foram mantidos em gaiolas de estudo de metabolismo para avaliação da digestibilidade das dietas e estimativa das concentrações dietéticas de EM e do consumo de proteína metabolizável. A degradabilidade das dietas experimentais foi avaliada in vitro. O consumo de matéria seca e o ganho de peso médio diário foram mais elevados para os animais alimentados com a dieta contendo feno de coastcross. Por outro lado, melhor eficiência alimentar foi observada para aqueles alimentados com a dieta contendo bagaço de cana. Não houve efeito do nível de consumo sobre o teor de energia metabolizável da dieta, mas este foi maior na dieta contendo bagaço de cana in natura (3,18 vs 2,94). Os animais recebendo a dieta contendo bagaço de cana apresentaram maiores concentrações corporais de gordura e energia, o que foi reflexo de um maior acúmulo de gordura visceral. O uso de volumosos de baixo valor nutricional, em dietas com alta concentração energética, não resulta em incremento das exigências energéticas de mantença. No entanto, a elevação do teor de concentrado da ração resulta em aumento da eficiência de uso da energia metabolizável para ganho de peso, o que está diretamente associado à maior retenção de gordura visceral. Sob o ponto de vista da produção de carne, todavia, esta maior eficiência nutricional deve ser vista com cautela, uma vez que está relacionada à deposição de tecidos não destinados ao consumo humano. As exigências protéicas para ganho de peso de cordeiros ½ Dorper × ½ Santa Inês podem ser acuradamente preditas pelas equações do AFRC (1993). Nenhum dos sistemas nutricionais atuais, contudo, é capaz de predizer as exigências energéticas destes animais entre os 15 e 45 kg de peso corporal. / The objective of this study was to evaluate the effect of using roughages with different nutritive value on requirements and efficiency of energy and protein use of growing ½ Dorper × ½ Santa Inês sheep. For this purpose, eighty four non-castrated male lambs were weaned at 56 days of age (initial BW = 18.0 ± 3.3 kg) and penned in individual stalls, being divided into two groups: VBVN - lambs fed diet containing roughage with low nutritive value (sugarcane bagasse in natura); and VAVN - lambs fed diet containing roughage with high nutritive value (coastcross hay). From these lambs, seven animals from each group were randomly selected and slaughtered after a 10-day adaptation period (reference animals). Twenty one animals in each group were then fed ad libitum and slaughtered at 25, 35, or 45 kg of live weight (seven animals per group), and the remaining 28 animals were submitted to one of two levels of feed restriction: either 70 or 50% of the ad libitum intake. Concentrations and retentions of body fat, nitrogen, and energy were determined. Additionally, six non-castrated males (PV mean = 52.3 ± 6.9 kg), canulated in the rumen, were kept in metabolic cages to evaluate diets digestibility, and to estimate metabolizable energy concentrations of the diets and the metabolizable protein intake. Diet degradability was assessed by an in vitro assay. Dry matter intake and average daily weight gain were higher for animals fed the diet containing coastcross hay. On the other hand, better gain-to-feed ratio was observed for those fed the diet containing sugarcane bagasse. There was no effect of intake level on metabolizable energy content of the diet, but it was higher in the diet containing sugarcane bagasse (3.18 vs. 2.94). Animals receiving the diet containing sugarcane bagasse presented higher body fat and energy concentrations, as a response of a larger visceral fat deposition. Using roughages with low nutritive value in high energy diets for growing lambs, does not increases energy requirements for maintenance. However, increasing concentrate proportion in the diet improves the efficiency of metabolizable energy use for weight gain, which is directly associated with a larger retention of visceral fat. Under a meat production perspective, however, that increased nutritional efficiency should be took with caution, since it is related to the deposition of tissues not intended to human consumption. Protein requirements for growth of lambs ½ Dorper × ½ Santa Inês are accurately predicted by the AFRC (1993) equations. None of the current nutritional systems, however, is able to predict energy requirements of these animals from 15 to 45 kg of body weight.