Obesity is a growing problem globally. Currently 2.3 billion adults are overweight, and this number is rising. The most common method for weight loss is calorie counting, in which to lose weight a person should be in a calorie deficit. Basal Metabolic Rate accounts for the majority of calories a person burns in a day and it is therefore a major contributor to accurate calorie counting. This paper uses a Dynamic Bayesian Network to estimate Basal Metabolic Rate (BMR) for a sample of 219 individuals from all Body Mass Index (BMI) categories. The data was collected through the Lifesum app. A comparison of the estimated BMR values was made with the commonly used Harris Benedict equation, finding that food journaling is a sufficient method to estimate BMR. Next day weight prediction was also computed based on the estimated BMR. The results stated that the Harris Benedict equation produced more accurate predictions than the metabolic model proposed, therefore more work is necessary to find a model that accurately estimates BMR.

Propósito: Observar obesas pré e pós-dieta hipocalórica moderada, mais treinamento em circuito ou caminhada. quanto a variáveis nutricionais. Métodos: Grupos: treinamento em circuito, CIRC, n = 26, índice de massa corporal (IMC, kg/m2) = 33,2 ± 7,9 (Média±desvio padrão); idade = 32,6 ± 9,7 anos; e treinamento em caminhada, CAM, n = 24, IMC = 29,2±3,4; idade = 38,8 ± 10,5 anos. Avaliações: a composição corporal, coleta de urina e sangue, calorimetria indireta e testes físicos eram obtidos no inicio (M1) e final (M2) do estudo. Treinamento: mês 1 = 1 h x 3 d/semana; e mês 2 = 1 h x 4 d/semana. Dieta: foi adaptada do registro alimentar de uma semana, ajustado ao gasto energético de repouso (GER) e balanceada, com a seguinte proporção: 20% de proteínas; 20% de gorduras; e 60% de carbohidratos. Resultados: Pré-intervenção: 76% tinham algum familiar obeso; havia sintomatologia indicativa de: 60% ansiosas, 12% depressivas, 34% compulsivas e 32% distúrbio do sono, avaliadas por questionário no exame clínico. Foram encontrados níveis alterados de colesterol total (CT, mg/dL), e ou frações em 22% das sujeitas. O peso, IMC, o índice abdômem/quadril (IAQ), a soma de oito pregas cutâneas (SP8) se correlacionaram significativamente a quatro variáveis bioquímicas, e a circunferência do abdômen (CAb), e o percentual de gordura por antropometria (%GAntro) a cinco. Intervenção: O peso, IMC, %GAntro, endomorfia, massa gorda por bioimpedância (MGBia) e percentual de gordura por bioimpedância (%GBia), foram reduzidos significativamente nos dois grupos. O CIRC melhorou significativamente em todos (seis) e o CAM em três testes físicos. O CIRC teve significância para: ¯glicose (Gli), ¯AU, ¯CT, ¯Tg (todos em mg/dL), ­glóbulos vermelhos (GV) (mm3) e ­hematócrito (Ht) (%); e o CAM para: ¯Gli, ¯AU, ¯HDL, ­CT/HDL, ­GV, ­Ht. O GER não teve diferença em ambos os grupos. Conclusões: Pré-intervenção: Os dados antropometricos indicam boa correlação com os fatores bioquímicos de risco, mas não tem uma tendência constante. A taxa CT/HDL apresentou correlação com todas as medidas antropométircas e a Gli com nenhuma. A obesidade destas mulheres parece ter múltiplos fatores e o estilo de vida papel determinante. Intervenção: A atividade física per se foi importante para causar modificações nutricionais e da composição corporal nestas obesas. O CIRC teve melhor associação com o incremento da performance física e dados bioquímicos sanguineos e ambos os grupos preservaram o GER. / Purpose: To observe obese women before and after a low-calorie diet plus circuit training or jogging regarding nutritional parameters. Methods: Groups: circuit training, CIRC, n = 26, body mass index (BMI, kg/m2) = 33.2 ± 7.9 (Mean±SD), age = 32.6 ± 9.7 years; and jogging training, JOGG, n = 24, BMI = 29.2 ± 3.4; age = 38.8 ± 10.5 years. Evaluations: body composition, collection of urine and blood samples, indirect calorimetry and physical tests were performed at the beginning (M1) and at the end (M2) of the study. Training: month one: 1 h x 3 d/week; month two: 1 h x 4 d/week. Diet: was adapted on the basis of a one week feeding record feed and adjusted to the resting metabolic rate (RMR) measured by indirect calorimetry, with the following proportion: 20% protein, 20% fat; and 60% carbohydrate. Results: Pre-intervention: 76% had one or more obese family members; there were symptoms indicating that 60% were anxious, 12% depressive, 34% compulsive, and 32% had sleep disorders, evaluated by a questionnaire during clinical examination. Altered levels of total cholesterol (TC) and/or fractions were found in 22% of the subjects. Weight (W), BMI, waist/hip ratio (WHR), and the sum of eight skin folds (8SF), were significantly correlated with four biochemistry variables, and abdominal circumference (AbC), and anthropometric fat percentage (%FAnthro) were correlated with five. Intervention: Weight, BMI, %FAnthro, endomorphy, body fat mass by bioimpedance (BFMBia) and percent body fat by bioimpedance (%FBia) were reduced in both groups. CIRC significantly increased performance in all (six) tests and the JOGG in three physical tests. CIRC showed significant differences for: ¯glucose (Glu), ¯UA, ¯TC (TC), ¯Tg (all in mg/dL), ­red blood cells (RBC) (mm3) and ­hematocrit (Ht) (%); and JOGG for: ¯Glu, ¯UA, ¯HDL, ­CT/HDL, ­RBC, ­Ht. The RMR was not significantly reduced in both groups. Conclusions: Pre-intervention: Anthropometric data indicated a good correlation with biochemical factors, but did not show a constant tendency. CT/HDL showed correlation with all anthropometric measurements and Glu with none. The obesity of these women appears to have multiple factors, with life style playing a determinant role. Intervention: Physical activities were determined to favor body composition, reduced weight and blood markers. CIRC were better in terms of physical performance and blood markers. Both types of training were sufficient to prevent a fall of RMR.

Background: Cerebral Palsy is usually divided into three subgroups: ataxic, spastic and dyskinetic, where children and adolescents can, because of misestimation in nutrition and energy intake, suffer from weight problems. Aim: To compare calculations with equations with the individual's measured RMR in the subgroups, to see if any equation is more suitable. This could be used as a tool to calculate the resting metabolism at times when it is not possible to perform clinical measurements. Method: The RMR has been measured in 37 children and adolescents aged 3-15 years through indirect respiratory calorimetry. Those values have been compared with calculations from five equations. The results were then analyzed in order to find if any equation is better to apply for calculating resting metabolism for each subgroup. Results: The ataxic group was overestimated by 56.5% of the calculated values. WHO/FAO/UNU’s equation indicates a significantly strong correlation between the measured and calculated values (r=0.85, p<0.05). The spastic group was underestimated by 53.3%. There is significance for all equations, however it is a relatively low correlation (r=0.63–0.66, p=0.02–0.03). The dyskinetic group was underestimated by 95%. There was no significant association between clinically measured values and the calculated resting metabolism (r=0.21–0.45, p=0.26–0.61). Conclusion: The equations are not reliable for calculation of energy need for all subgroups. There is a substantial risk of over- and underestimation, therefore awareness of the equations insufficiency is needed. Studies should be performed with additional basic data, and with more equations. Especially equations including further variables that involves the body composition. / Bakgrund: Cerebral Pares brukar delas in i undergrupper: ataktisk, spastisk och dyskinetisk, där barn och ungdomar kan, beroende på felskattningar av näringsintag och energiberäkning, lida av över- eller undervikt. Syfte: Att jämföra uträkningar med ekvationer med individernas uppmätta vilometabolism i de tre undergrupperna, för att se om någon ekvation lämpar sig bättre. Detta skulle kunna ge ett verktyg för att kunna räkna ut vilometabolismen vid de tillfällen då det inte är möjligt att utföra kliniska mätningar. Metod: Mätningar av vilometabolismen har utförts på 37 barn och ungdomar i åldern 3-15 år genom indirekt respiratorisk kalorimetri. Värdena har jämförts med uträkningar från fem ekvationer. Resultatet har sedan analyserats, för att hitta någon ekvation som är bättre lämpad för att räkna ut vilometabolismen, för respektive undergrupp. Resultat: Den ataktiska gruppen överskattades i 56,5% av uträkningarna av vilometabolism. WHO/FAO/UNUs ekvation påvisar ett signifikant starkt samband mellan det uppmätta och uträknade värdena (r=0,85, p<0,05). Den spastiska gruppen underskattades 53,3% av de uträknade värdena. Det föreligger signifikans för alla ekvationer, dock ett relativt lågt samband (r=0,63–0,66, p=0,02–0,03). Den dyskinetiska gruppen underskattades i 95 %. Det förelåg inget signifikant samband mellan kliniskt uppmätt och uträknad vilometabolism (r=0,21–0,45, p=0,26–0,61). Slutsats: Ekvationerna är inte tillförlitliga för uträkning av energibehov för alla undergrupper. Risk för över- och underskattning är överhängande, och en ökad medvetenhet om ekvationernas ofullständighet måste belysas. Studier bör göras med större underlag och med fler ekvationer. Framförallt ekvationer med fler variabler som tar hänsyn till kroppssammansättning.

Obesity in children and adolescents is on the rise and is a major risk factor for chronic disease, thus posing one of the greatest public health challenges for the 21st century. Although adolescent obesity is increasing in all ethnic groups, its prevalence is higher in non–Caucasian populations. A possible explanation for ethnic differences in the development of obesity could be ethnic differences in resting metabolic rate (RMR). A low RMR would pre–dispose an ethnic group to obesity. In South Africa limited research has been published with regards to body composition (BC) and RMR in adolescents and the possible association of RMR with BC. The first aim of this study, therefore, was to determine differences in BC and RMR between 14 year old black and Caucasian South African adolescents from the Tlokwe municipality of the North West Province, South– Africa. The second aim was to investigate whether significant relationships between the body composition characteristics body mass index (BMI), percentage body fat (%BF), fat free mass (FFM) and RMR exist in this group. The baseline data of participants in the Physical Activity and Health Longitudinal Study (PAHLS) was used. Anthropometric measurements included stature, body mass, triceps and subscapular skinfolds, and waist girth to determine BMI, %BF, FFM and waist–to–height ratio (WHTR). RMR was measured by the FitMate Pro Indirect Calorimetry (Cosmed). An independent t–test was used to compare the two groups (black vs. Caucasian, boys and girls respectively) with regards to body composition and RMR. Pearson correlation coefficients (adjusted for gender and ethnicity) were calculated, to study the relationship between RMR and body composition. Significant difference levels were set at p<0.05. The present cross–sectional results revealed significant differences in BC and RMR in black and Caucasian adolescents of the Tlokwe municipality, with Caucasian adolescents of both genders having a higher RMR and FFM compared to their counterpart black adolescents. The results further indicated that Caucasian adolescents were significantly (p<0.05) taller, heavier and had a higher %BF, WHTR, FFM and RMR than the black adolescents of both genders. Boys of both ethnicities had a higher RMR than the girls, with black girls having the lowest RMR. Both underweight and overweight/obesity were present in both ethnic groups and genders emphasizing the double burden of disease prevalent in South Africa. The overweight/obese group of both ethnicities had a higher FFM and RMR than the normal and underweight group. After adjusting for gender and ethnicity a high non–significant negative relationship was observed between RMR and FFM in the overweight group. The reasons for these persistent differences in ethnic groups for RMR in adolescents are not clear. A positive association between anthropometric indicators of BC and RMR influenced by gender and ethnicity was indicated. Whether the observed ethnic differences in RMR predict future weight gain and obesity awaits the results of longitudinal analyses. It is suggested that intervention programmes be implemented focusing on the prevention of obesity in adolescents, but especially black adolescent girls, as they are indicated to be the group more prone to obesity. These results supported the literature findings and identified the need for longitudinal data regarding RMR and BC in adolescents. The PAHL–Study will continue to follow–up these adolescents over a period of time as some of the conclusions made will further be cleared, including whether the observed ethnic differences in RMR predict future weight gain and obesity. / Thesis (M.Sc. (Biokinetics))--North-West University, Potchefstroom Campus, 2012.

Obesity in children and adolescents is on the rise and is a major risk factor for chronic disease, thus posing one of the greatest public health challenges for the 21st century. Although adolescent obesity is increasing in all ethnic groups, its prevalence is higher in non–Caucasian populations. A possible explanation for ethnic differences in the development of obesity could be ethnic differences in resting metabolic rate (RMR). A low RMR would pre–dispose an ethnic group to obesity. In South Africa limited research has been published with regards to body composition (BC) and RMR in adolescents and the possible association of RMR with BC. The first aim of this study, therefore, was to determine differences in BC and RMR between 14 year old black and Caucasian South African adolescents from the Tlokwe municipality of the North West Province, South– Africa. The second aim was to investigate whether significant relationships between the body composition characteristics body mass index (BMI), percentage body fat (%BF), fat free mass (FFM) and RMR exist in this group. The baseline data of participants in the Physical Activity and Health Longitudinal Study (PAHLS) was used. Anthropometric measurements included stature, body mass, triceps and subscapular skinfolds, and waist girth to determine BMI, %BF, FFM and waist–to–height ratio (WHTR). RMR was measured by the FitMate Pro Indirect Calorimetry (Cosmed). An independent t–test was used to compare the two groups (black vs. Caucasian, boys and girls respectively) with regards to body composition and RMR. Pearson correlation coefficients (adjusted for gender and ethnicity) were calculated, to study the relationship between RMR and body composition. Significant difference levels were set at p<0.05. The present cross–sectional results revealed significant differences in BC and RMR in black and Caucasian adolescents of the Tlokwe municipality, with Caucasian adolescents of both genders having a higher RMR and FFM compared to their counterpart black adolescents. The results further indicated that Caucasian adolescents were significantly (p<0.05) taller, heavier and had a higher %BF, WHTR, FFM and RMR than the black adolescents of both genders. Boys of both ethnicities had a higher RMR than the girls, with black girls having the lowest RMR. Both underweight and overweight/obesity were present in both ethnic groups and genders emphasizing the double burden of disease prevalent in South Africa. The overweight/obese group of both ethnicities had a higher FFM and RMR than the normal and underweight group. After adjusting for gender and ethnicity a high non–significant negative relationship was observed between RMR and FFM in the overweight group. The reasons for these persistent differences in ethnic groups for RMR in adolescents are not clear. A positive association between anthropometric indicators of BC and RMR influenced by gender and ethnicity was indicated. Whether the observed ethnic differences in RMR predict future weight gain and obesity awaits the results of longitudinal analyses. It is suggested that intervention programmes be implemented focusing on the prevention of obesity in adolescents, but especially black adolescent girls, as they are indicated to be the group more prone to obesity. These results supported the literature findings and identified the need for longitudinal data regarding RMR and BC in adolescents. The PAHL–Study will continue to follow–up these adolescents over a period of time as some of the conclusions made will further be cleared, including whether the observed ethnic differences in RMR predict future weight gain and obesity. / Thesis (M.Sc. (Biokinetics))--North-West University, Potchefstroom Campus, 2012.

Made available in DSpace on 2015-07-22T20:50:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-27 / Introdução/Objetivo: Os fatores orexígenos e anorexígenos e a Taxa Metabólica de Repouso (TMR) desenvolvem um importante papel no controle e regulação do balanço energético e estão diretamente relacionados com a obesidade. Com base nesta relação, o objetivo desta pesquisa foi verificar os efeitos do tratamento multidisciplinar de longo prazo nos fatores orexígenos e anorexígenos e na TMR em adolescentes obesos. Metodologia: No presente estudo foram selecionados 20 adolescentes obesos (11 meninas e 9 meninos), com idade entre 14 e 19 anos. Os critérios de inclusão foram o IMC percentil > 95 de acordo com o Centers for Disease Control and Prevention e estágio de maturação sexual pós púbere. Os fatores orexígenos e anorexígenos foram avaliados por radioimunoensaio. A TMR foi mensurada por calorimetria indireta, a composição corporal por Pletismografia e a gordura visceral e subcutânea por Ultra-sonografia. Resultados: Após 12 meses de intervenção, os adolescentes obesos apresentaram diminuição significativa na massa corporal total, no IMC, na gordura corporal (% e em kg,), na massa magra (kg), e na gordura visceral e subcutânea. O grupo não apresentou diminuição significativa da TMR. Os fatores anorexígenos diminuíram significativamente e o MCH aumentou ao término da terapia. Conclusão: Podemos concluir que a terapia multidisciplinar de longo prazo foi efetiva para melhorar a composição corporal, os fatores orexígenos e anorexígenos, contribuindo para o controle da obesidade e do balanço energético. Palavras-Chave: Fatores orexígenos e anorexígenos; taxa metabólica de repouso; adolescente obeso; terapia multidisciplinar. / Background/Aims: anorexigenic and orexigenic factors and resting metabolic rate (RMR) play an important role in the energy balance and they are directly related to obesity. In this way, it was verified the effects of long-term multidisciplinary therapy on orexigenic and anorexigenic factors and resting metabolic rate in obese adolescents. Methods: Twenty obese adolescents (11 girls and 9 boys) aged between 14 and 19 years, BMI > 95th percentile of CDC, were submitted to intensive long-term multidisciplinary therapy during 12 months. Orexigenic and anorexigenic factors concentrations were measured by a radioimmunoassay (RIA) kit. RMR was measured by indirect calorimetry. Body composition was measured by pletismography, and visceral and subcutaneous fat were analyzed by ultrassonography. Results: After one year of multidisciplinary therapy, the obese adolescents presented a significant decrease in body mass (p<0.001), BMI (p<0.001), fat mass (kg and %), lean mass (kg), subcutaneous and visceral fat. The group did not decrease significantly in RMR and RMR/FFM. The anorexigenic factors (leptin and alpha- MSH concentrations) decreased significantly. The orexigenic neuropeptide (MCH) increased by the end of the multidisciplinary therapy. Conclusion: Our investigation demonstrated that long-term multidisciplinary therapy was effective to improve body composition, anorexigenic and orexigenic factors contributing to obesity control. / TEDE / BV UNIFESP: Teses e dissertações

The oxygen consumption and body temperature were measured in adults and pups of a social Mashona mole-rat(Fukomys darlingi)to test poikilothermic traits in this species and effect of presence of adults on pup´s thermoregulation abilities. The adult´s resting metabolic rate was 0.76 {$\pm$} 0.20 mlO2g-1hod-1 in the thermoneutral zone 27-34°C. We did not confirm poikilotermic traits in this species, because body temperature was stable (33.0 {$\pm$} 0.5°C) at low ambient temperatures. The pups started to thermoregulate in age of one month and they are able to maintain stable body temperature very late in age of three months. My results indicate that presence of adults is necessary for thermoregulation of pups.

The oxygen consumption and body temperature were measured in adults and pups of a social Mashona mole-rat(Fukomys darlingi)to test poikilothermic traits in this species and effect of presence of adults on pup´s thermoregulation abilities. The adult´s resting metabolic rate was 0.76 {$\pm$} 0.20 mlO2g-1hod-1 in the thermoneutral zone 27-34°C. We did not confirm poikilotermic traits in this species, because body temperature was stable (33.0 {$\pm$} 0.5°C) at low ambient temperatures. The pups started to thermoregulate in age of one month and they are able to maintain stable body temperature very late in age of three months. My results indicate that presence of adults is necessary for thermoregulation of pups.

Propósito: Observar obesas pré e pós-dieta hipocalórica moderada, mais treinamento em circuito ou caminhada. quanto a variáveis nutricionais. Métodos: Grupos: treinamento em circuito, CIRC, n = 26, índice de massa corporal (IMC, kg/m2) = 33,2 ± 7,9 (Média±desvio padrão); idade = 32,6 ± 9,7 anos; e treinamento em caminhada, CAM, n = 24, IMC = 29,2±3,4; idade = 38,8 ± 10,5 anos. Avaliações: a composição corporal, coleta de urina e sangue, calorimetria indireta e testes físicos eram obtidos no inicio (M1) e final (M2) do estudo. Treinamento: mês 1 = 1 h x 3 d/semana; e mês 2 = 1 h x 4 d/semana. Dieta: foi adaptada do registro alimentar de uma semana, ajustado ao gasto energético de repouso (GER) e balanceada, com a seguinte proporção: 20% de proteínas; 20% de gorduras; e 60% de carbohidratos. Resultados: Pré-intervenção: 76% tinham algum familiar obeso; havia sintomatologia indicativa de: 60% ansiosas, 12% depressivas, 34% compulsivas e 32% distúrbio do sono, avaliadas por questionário no exame clínico. Foram encontrados níveis alterados de colesterol total (CT, mg/dL), e ou frações em 22% das sujeitas. O peso, IMC, o índice abdômem/quadril (IAQ), a soma de oito pregas cutâneas (SP8) se correlacionaram significativamente a quatro variáveis bioquímicas, e a circunferência do abdômen (CAb), e o percentual de gordura por antropometria (%GAntro) a cinco. Intervenção: O peso, IMC, %GAntro, endomorfia, massa gorda por bioimpedância (MGBia) e percentual de gordura por bioimpedância (%GBia), foram reduzidos significativamente nos dois grupos. O CIRC melhorou significativamente em todos (seis) e o CAM em três testes físicos. O CIRC teve significância para: ¯glicose (Gli), ¯AU, ¯CT, ¯Tg (todos em mg/dL), ­glóbulos vermelhos (GV) (mm3) e ­hematócrito (Ht) (%); e o CAM para: ¯Gli, ¯AU, ¯HDL, ­CT/HDL, ­GV, ­Ht. O GER não teve diferença em ambos os grupos. Conclusões: Pré-intervenção: Os dados antropometricos indicam boa correlação com os fatores bioquímicos de risco, mas não tem uma tendência constante. A taxa CT/HDL apresentou correlação com todas as medidas antropométircas e a Gli com nenhuma. A obesidade destas mulheres parece ter múltiplos fatores e o estilo de vida papel determinante. Intervenção: A atividade física per se foi importante para causar modificações nutricionais e da composição corporal nestas obesas. O CIRC teve melhor associação com o incremento da performance física e dados bioquímicos sanguineos e ambos os grupos preservaram o GER. / Purpose: To observe obese women before and after a low-calorie diet plus circuit training or jogging regarding nutritional parameters. Methods: Groups: circuit training, CIRC, n = 26, body mass index (BMI, kg/m2) = 33.2 ± 7.9 (Mean±SD), age = 32.6 ± 9.7 years; and jogging training, JOGG, n = 24, BMI = 29.2 ± 3.4; age = 38.8 ± 10.5 years. Evaluations: body composition, collection of urine and blood samples, indirect calorimetry and physical tests were performed at the beginning (M1) and at the end (M2) of the study. Training: month one: 1 h x 3 d/week; month two: 1 h x 4 d/week. Diet: was adapted on the basis of a one week feeding record feed and adjusted to the resting metabolic rate (RMR) measured by indirect calorimetry, with the following proportion: 20% protein, 20% fat; and 60% carbohydrate. Results: Pre-intervention: 76% had one or more obese family members; there were symptoms indicating that 60% were anxious, 12% depressive, 34% compulsive, and 32% had sleep disorders, evaluated by a questionnaire during clinical examination. Altered levels of total cholesterol (TC) and/or fractions were found in 22% of the subjects. Weight (W), BMI, waist/hip ratio (WHR), and the sum of eight skin folds (8SF), were significantly correlated with four biochemistry variables, and abdominal circumference (AbC), and anthropometric fat percentage (%FAnthro) were correlated with five. Intervention: Weight, BMI, %FAnthro, endomorphy, body fat mass by bioimpedance (BFMBia) and percent body fat by bioimpedance (%FBia) were reduced in both groups. CIRC significantly increased performance in all (six) tests and the JOGG in three physical tests. CIRC showed significant differences for: ¯glucose (Glu), ¯UA, ¯TC (TC), ¯Tg (all in mg/dL), ­red blood cells (RBC) (mm3) and ­hematocrit (Ht) (%); and JOGG for: ¯Glu, ¯UA, ¯HDL, ­CT/HDL, ­RBC, ­Ht. The RMR was not significantly reduced in both groups. Conclusions: Pre-intervention: Anthropometric data indicated a good correlation with biochemical factors, but did not show a constant tendency. CT/HDL showed correlation with all anthropometric measurements and Glu with none. The obesity of these women appears to have multiple factors, with life style playing a determinant role. Intervention: Physical activities were determined to favor body composition, reduced weight and blood markers. CIRC were better in terms of physical performance and blood markers. Both types of training were sufficient to prevent a fall of RMR.

Bakgrund: En del elitidrottare, exempelvis inom uthållighetsgrenar, genomför högträningsvolym vilket stressar kroppen. Hög träningsvolym resulterar i högenergiförbrukning vilket kräver ett stort energiintag. Ett otillräckligt energiintag påverkarkroppen fysiologiskt på ett flertal sätt och kan leda till syndromet relativ energibrist iidrott (REI - S). Syftet Studiens syfte var att studera samband mellankroppssammansättning och viloomsättning (RMR) korrelerat till relativ energibrist hossvenska elitidrottare. Metod/Urval: Studien följde en tvärsnittsstudiedesign. Mätning avkroppskomposition (fettmassa och fettfri massa) samt viloomsättning (RMR) utfördes.RMRratio beräknades genom mätt RMR (mRMR) delat på beräknad RMR (pRMR).mRMR beräknades under laborationen och pRMR beräknades genom Cunningham1991ekvationen. Urvalet bestod av 23 svenska elitidrottare från olika sporter med ettåldersspann från 18 år - 43 år. Resultat: Procentuell fettfri massa (FFM %) och RMR -värde korrelerade positivt (r = 0,47, p = 0,023). En negativ måttligt stark korrelationberäknades mellan procentuell fettmassa (FM %) och RMR - värde (r = -0,47, p = 0,024). Slutsats Därmed korrelerade kroppssammansättning och viloomsättning hos svenskaelitidrottare. Viloomsättning korrelerade positivt med FFM % och negativt med FM %. / Background Some elite athletes, such as endurance runners, undergo extreme levels of training volume which stresses the body. High training volume results in high energy expenditure which requires a large energy intake. Consequences of insufficient amounts of energy intake are physiological dysfunctions and may lead to relative energy deficiency in sports (RED- S). Purpose The aim of the study was to research relations between body composition (FM, FFM) and resting metabolic rate (RMR) in correlation with RED-S amongst Swedish elite athletes. Method/Subjects This research follows a cross-sectional study design. Measurements to calculate body composition and RMR were performed. RMRratio was calculated by measured RMR (mRMR) divided by predicted RMR (pRMR). The Cunningham1991 equation was used to calculate pRMR. A total of 23 healthy Swedish elite athletes from different sports were measured, age ranging from 18 - 43 year olds. Results The percentage of fat free mass (FFM %) correlated positively with RMR (r = 0,47, p = 0,023). Percentage of fat mass (FM %) correlated negatively with RMR (r = - 0,47, p = 0,024). Conclusion A correlation between body composition and RMR amongst Swedish elite athletes was discovered. RMR correlated positively with FFM%  and negatively with FM%.