The effects of either 12-wk of high-intensity endurance or resistance training on resting metabolic rate (RMR) were investigated in 47 males aged 18-35 y. Subjects were randomly assigned to either a control (C), resistance- trained (RT) or endurance-trained (ET) group. After training both exercise groups showed significant declines in relative body fat either by reducing their total fat weight and maintaining fat-free weight (ET) or by reducing their total fat weight and increasing fat-free weight (RT). RMR did not significantly change after either training regimen although a small decline in energy intake was observed along with an increase in energy expenditure [ET, 2.721 MJ (650 kcal) per training day]. These results suggest that both endurance and resistance training may help to prevent an attenuation in RMR normally observed during extended periods of negative energy balance (energy intake < expenditure) by either preserving or increasing a person's fat-free weight.

A cross-sectional study was designed to determine the relationship between aerobic fitness and resting metabolic rate (RMR) in 69 males exhibiting a wide range of aerobic fitness levels (V̇O2max = 32.8-78.1 mL · kg-1 · min-1). The results of this study indicated that RMR was not significantly different between trained and untrained individuals when expressed in kJ · kg fat-free weight-1 · hr-1 or using an ANCOVA with fat-free weight as the covariate and RMR as the dependent variable (F ratio = 0.353, P < 0.70). In addition, this study also failed to support a previously suggested hypothesis that an elevated RMR may only be observed in those individuals exhibiting both high V̇O2max values and currently training a minimum of 12- 16 h/wk. Thus, the results of this study strongly suggest that RMR is independent of both a person's current aerobic level and training status.

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The two most common methods to measure resting metabolic rate using indirect calorimetry are steady state or time interval. Steady state is commonly defined as the first five minutes in which oxygen consumption and carbon dioxide production vary by <10%. A time interval measurement generally lasts 20-60 minutes. Using steady state criteria is often harder to achieve, but many suggest it more accurately measures resting metabolic rate. Our objective was to determine if there were differences between steady state and time interval measurements in a healthy adult population. Seventy seven subjects were measured for 45 minutes. Inclusion criteria included healthy subjects ages 18-65, excluding pregnant and lactating women. Paired t-tests analyzed differences between measures, and Bland-Altman plots evaluated bias, precision, and accuracy. Of 77 subjects, 84% achieved steady state, and 95% achieved SS by minute 30. Most differences between steady state and time intervals were statistically but not practically significant. Bland-Altman plots showed steady state measurements were generally lower indicating that steady state is more indicative of resting metabolic rate. Minutes 6-25 were most precise, accurate and fairly unbiased compared to steady state. We recommend measuring a subject for 30 minutes and using steady state criteria of <10% variation of oxygen consumption and carbon dioxide production for five minutes if a subject is able to achieve it. However, if a subject cannot achieve steady state, we recommend averaging minutes 6-25.

This study measured total daily energy expenditure (TDEE) in adults at least 50 years of age. The goal was to determine the effect of the estimate of resting metabolic rate (RMR) on the relationship between energy expenditure estimates made using (a) self-reports of physical activity and (b) food intake records. The objectives were to determine if (a) RMR estimates based on body composition, body weight, and the 111 metabolic cart were strongly related to each other, and (b) TDEE estimates based on a 7- day physical activity diary and a 7-day food intake record were more strongly related to each other when an RMR was used that was based on body composition, body weight, or the met cart. This was a three-phase study. In phases I and II, the Pearson r was computed for all combinations of methods . If r > .80, the most practical method for field use was used in the next phase. Phase I: Estimated body composition using bioimpedance (BIA), skinfold (SKF), and girth. Phase II: Measured RMR using a met cart and three equations. Phase III: Computed TDEE using the self-reports. The Pearson r was computed to determine which methods of estimating RMR resulted in the strongest relationships. Forty-four older adults participated. Phase I: r = .88 for SKF, girth; r = .64 for SKF, BIA. Phase II: rs ranged from .47 to .59 between the met cart-RMR and all the other methods; rs ranged from .84 to .98 for the remaining methods. Phase III: r = .41 between the two estimates of TDEE that used a body weight -RMR; r = .59 between estimates using a met cart-RMR; and r = .58 between estimates using a body composition-RMR. Even though r = .59 and r = .58 are similar, the average individual difference between the two estimates for each participant was smaller for the metabolic cart- RMR (372 calories /day) than for the body composition-RMR (1,045 calories /day), which suggests that body composition is not as useful as a met cart when estimating TDEE for older adults . When estimating clients' daily calorie needs, health professionals ought to consider using a met cart to estimate RMR and TDEE instead of other methods .

Orientador: Maria Rita Marques de Oliveira / Banca: Maria Rita Marques de Oliveira / Banca: Maria Jacira Silva Simões / Banca: Rozangela Verlengia / Resumo: A obesidade é uma doença estreitamente relacionada ao desenvolvimento da síndrome metabólica (SM) e é fundamentalmente um problema de balanço energético que se desenvolve quando a ingestão de energia proveniente dos alimentos é maior que o gasto energético total. O gasto energético total compreende a taxa metabólica de repouso, o efeito térmico dos alimentos e os gastos com atividade física e pode ser medido pela calorimetria indireta. O objetivo deste trabalho foi estudar a relação da taxa metabólica de repouso (TMR) em mulheres obesas com os componentes da SM e fatores relacionados. O grupo de estudo foi constituído por 35 mulheres com idade entre 18 e 40 anos, que apresentavam um índice de massa corporal (IMC) maior ou igual a 30 kg/m². Foram excluídas as mulheres portadoras de diabetes mellitus, hipotireoidismo, gestantes, lactantes e aquelas em tratamento (medicamentoso ou não) para obesidade e dislipidemias, além das portadoras de doenças graves. Foram aplicados um questionário para obtenção de dados sócio-demográficos, três recordatórios de 24 horas em dias não consecutivos sendo um final de semana e três diários de atividade física, aplicados no mesmo dia dos recordatórios. O comportamento alimentar foi avaliado pela escala de compulsão alimentar periódica (ECAP). Dentre as variáveis antropométricas foram avaliadas peso, estatura, circunferência de cintura, quadril e braço. A composição corporal (percentual de gordura e massa magra) foi avaliada pela bioimpedância elétrica e a TMR foi avaliada por meio do analisador de gases VO2000 MedGraphicsÒ. Foram ainda dosados em sangue o colesterol total e frações, glicose, insulina, proteína C reativa e triglicérides. As mulheres foram agrupadas quanto à presença ou não de SM e em tercil de TMR ajustada para a massa corporal (TMR/MC)... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: It is known that obesity, a disease closely related to the development of the metabolic syndrome (MS), is basically a problem of energy balance and develops when energy intake exceeds total energy expenditure. Total energetic expenditure includes basal metabolic rate, the thermogenic effect of food and expenditures with physical activity and can be determined by indirect calorimetry. The objective of this study was to relate the basal metabolic rate (BMR) of obese women with MS components and related factors. The studied group included 35 women aged 18 to 40 years with a body mass index equal to or above 30 kg/m². Women with diabetes mellitus, hypothyroidism, severe diseases, women being treated for obesity and dyslipidemias and pregnant and lactating women were excluded from this study. A questionnaire to obtain sociodemographic data, three 24-hour dietary recalls in non-consecutive days one being during the weekend and three physical activity diaries administered on the same day as the 24-hour recalls were administered. Eating behavior was assessed by the binge eating scale (BES). The following anthropometric variables were assessed: weight, height and waist, hip and arm circumferences. Body composition (percentage of fat and lean mass) was determined by electrical bioimpedance and the basal metabolic rate was assessed by the gas exchange testing system MedGraphics VO2000®. The women were divided into groups with and without the MS and in BMR terciles adjusted for body mass (BMR/BM). The results showed that there was no significantly statistical difference between the groups with and without the MS regarding income, physical activity, presence of binge eating disorder, dietary macronutrient and micronutrient composition, energy intake, BMR, respiratory quotient (RQ), BMR/BM or MBR/LM. When the women were divided into BMR/BM terciles, BMR/BM was not associated with MS components... (Complete abstract click electronic access below) / Mestre

The role of divergent climate adaptation in speciation has received surprisingly little scientific attention. My dissertation research focused on how resting metabolic rate (RMR) relates to the build up of prezygotic and postzygotic isolation in a natural Ficedula flycatcher hybrid zone. RMR is the amount of energy an organism needs to run its internal organs. Since RMR is related to life history traits and thermoregulation in other systems, it is likely to affect speciation processes at secondary contact. I found that adult collared flycatchers displace pied flycatchers into increasingly poor habitats (Paper I). Pied nestlings exhibit lower RMR in poor environments (Paper II), which may promote regional coexistence and habitat isolation by making it possible for pied flycatchers to escape competition from collared flycatchers and reduce the risk of hybridization by breeding in the poorer habitats. Further, I found that while collared flycatcher nestling RMR was not environmentally-dependent (Paper II, Paper III), those collared flycatcher nestlings that had a lower RMR in poor environments tended to have higher condition (Paper III). Further, RMR was genetically linked to a sexual ornament in collared males that has previously been shown to be beneficial in poor environments. Lastly, I found that by seven days old, nestlings increase their metabolic rate when listening to song, indicating that they are listening, and by 9 days they can discriminate between songs (Paper IV). Taken together, RMR could affect pre-zygotic isolation via correlations with life history strategies, song and sexual ornaments. RMR is also related to post zygotic isolation in Ficedula flycatchers. I found that flycatcher hybrids tended to have a higher RMR than the parental species (Paper V), and that there were many differentially expressed genes in energetically expensive organs in hybrids that were related to metabolic function (Paper VI). Thus, metabolic dysfunction, possibly caused by genetic incompatibilities, in Ficedula flycatcher hybrids could be a factor leading to infertility and postzygotic isolation between the parental species. Overall, I find that RMR could be a general physiological trait that affects both pre- and postzygotic isolation in hybridizing species at secondary contact, and ought to be more thoroughly considered in speciation research.

Resting metabolic rate (RMR) represents the lowest level of aerobic metabolism in a resting individual. By contrast, maximal metabolic rate (MMR) reflects the upper limit of aerobic metabolism achieved during intensive exercise. As RMR and MMR define the boundaries of the possible levels of metabolism expressed by a normothermic individual, a key question is whether RMR and MMR are correlated. To evaluate the relationship between RMR and MMR, I took repeated paired measurements of RMR and MMR on 165 white-footed mice (Peromyscus leucopus) during the summer of 2018. Repeatability (R±se) was significant for both RMR and MMR (RRMR=0.15±0.07 and RMMR=0.27±0.12). At the residual level (within-individual), RMR and MMR were significantly and positively correlated (re=0.20, 95% confidence intervals: 0.04, 0.34). Such a positive residual correlation could be result of correlated phenotypic plasticity. By contrast, RMR and MMR were significantly and negatively correlated at the among-individual level (rind=-0.87, 95% confidence intervals: -0.99, -0.28). The negative among-individual correlation suggests there are trade-offs between the maintenance and active components of the energy budget (allocation model). Future research should investigate the relationship between RMR and other energetically expensive behaviours and activities to understand how energy is allocated among individuals.

Introduction: Changes in eating habits and incorporation of physical activities remain to be the main methods in treating obesity. To set an adequate calorie intake, which would lead to weight loss, it is necessary to determine energy needs of an individual. For that energy intake and energy expenditure need to be determinate. However, energy expenditure is difficult to determine since it is contributed of three components. Basal, respectively resting metabolic rate (RMR), which is affected by a body composition, has the greatest influence on a total energy expenditure. Indirect calorimetry (IC) is considered to be a gold standard to determine RMR. When RMR is calculated by prediction equations instead, such as Harris-Benedict (H-B) equation, energy needs are overestimate or underestimate for people with abnormal body composition. Objectives: The aim of this study is to analyse data of RMR obtained using IC in connection to body composition. The main aim is to determine how fat free mas (FFM) and fat mass (FM) are affecting RMR in obese patients. There is also a comparation of RMR measured by the IC and RMR calculated using H-B equation as a part of this study, while IC is considered to be a reference method. Methods: Patients new to ambulance of obesitology at General University Hospital in Prague...

The purpose of this study was to investigate the role exercise intensity plays in reducing body weight and percent body fat in overweight women. Subjects were randomized to either a high intensity interval training group (IT) or a lower intensity steady state training group (ST). Each group exercised 3 times per week for 8 weeks and expended 300 kcal per exercise session. VO2max, body composition, and resting metabolic rate (RMR) were measured pre and post training. RMR was measured after exercise at week 2 to see if intensity levels affected RMR. VO2max and body composition improved in IT but not in ST. Neither group showed a change in RMR from pretest to posttest; however, IT had an increase in RMR 24 hours post-exercise whereas ST did not. These findings show that high intensity interval exercise produces improvements in body composition, fitness, and acute RMR compared to low intensity steady state training.