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Klaas R. Westerterp - One of the best experts on this subject based on the ideXlab platform.
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Nutrition Research Methodologies - Energy Expenditure and Intake Methods
Nutrition Research Methodologies, 2015Co-Authors: Klaas R. WesterterpAbstract:The main components of total Energy Expenditure are Energy Expenditure for maintenance or basal metabolic rate, the thermic effect of food or diet-induced Energy Expenditure (DEE), and the Energy cost of physical activity or activity-induced Energy Expenditure (AEE). This chapter describes methods to measure Energy Expenditure, determinants of Energy Expenditure and the application of Energy Expenditure measurements for the evaluation of intake methods. The methods section includes techniques, methods to measure separate components of daily Energy Expenditure, and measuring substrate utilisation. The determinants section describes the subject characteristics involved, such as body composition, age and gender, and behavioural aspects including food intake and physical activity. Evaluation of intake methods is based on principles of Energy requirement and techniques to assess Energy homeostasis. In the adult population, the prevalence of overweight has increased and at the same time reported Energy intake and %Energy from fat have decreased.
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Measurement of Energy Expenditure
Translational Research Methods for Diabetes Obesity and Cardiometabolic Drug Development, 2014Co-Authors: Klaas R. WesterterpAbstract:At the present state of the art, Energy Expenditure is measured with indirect calorimetry, where Energy production is calculated from oxygen consumption, carbon dioxide production and urine-nitrogen loss. Daily Energy Expenditure consists of three components, i.e., maintenance Expenditure, diet-induced Energy Expenditure and activity-induced Energy Expenditure. Designing studies to evaluate intervention effects on Energy Expenditure, including drugs, should be based on the Energy Expenditure component as targeted. The indicated method for the measurement of maintenance Expenditure and diet-induced Energy Expenditure is a respiration chamber or a ventilated hood. Activity-induced Energy Expenditure is measured under free-living conditions with doubly labelled water. Energy Expenditure can additionally be estimated with prediction equations for maintenance Expenditure, based on height, weight, age and gender; doubly labelled water validated accelerometers to assess activity-induced Energy Expenditure; and measurements of food intake as evaluated with the doubly labelled water technique.
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Limits in Energy Expenditure
Energy Balance in Motion, 2012Co-Authors: Klaas R. WesterterpAbstract:The research on the ceiling value of four times resting Energy Expenditure, as observed in birds, got support from observations on endurance performance in man. House Martins, Sand Martins and Swallows reach a performance ceiling in the most active phase of the annual cycle: the time when they are feeding chicks at the nest. Man nowadays reaches a ceiling during performances like endurance sport events. Here, limits in Energy Expenditure are illustrated with typical examples: endurance athletes while participating in the Tour de France; Olympic cross-country skiers during a training stage; and sailors during a leg of the ‘Whitbread race’. Sailing does not seem to be a high intensity exercise, however, there is a continuous need to counterbalance the movements of the boat leading to an unexpectedly high workload. Non-athletes can be trained to reach an Energy ceiling. Here, the examples include: subjects preparing to run a half-marathon; overweight boys training on a cycle ergometer; and men performing weight training in a fitness centre. In all studies, the Energy ceiling is assessed by measurement of total Energy Expenditure with doubly labelled water. In the non-athletes, the effect of training on the activity factor was assessed with measurements before and after the training. The Energy ceiling for non-athletes occurs at an activity factor of 2.0 to 2.5. A further increase in activity is difficult to sustain for more than a week, but if one does so, one loses weight. This loss of weight will eventually result in a loss of performance. Exceptions are professional endurance athletes. They are a selection of the population, born to be athletes, training for many years to reach their high level of performance. The training includes exercise and the maintenance of Energy balance at a high level of Energy turnover. The latter implicates the supplementation of the diet with Energy drinks. Highly trained athletes have learned to eat the maximum amount of food during hard physical work. Endurance athletes like professional cycle racers and Olympic cross-country skiers can reach an activity factor around 4.0 and maintain this value for one or more weeks. Non-athletes reach an Energy Expenditure ceiling at an activity factor of 2.0–2.5. This value is already reached after a 5–10-week endurance training program. Maintaining this high level of Energy Expenditure requires higher and higher training intensities because of the increased movement efficiency. A higher body weight decreases the likelihood of compliance with such a training program, especially when the training involves body displacement as in running.
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Physical activity as determinant of daily Energy Expenditure.
Physiology & behavior, 2008Co-Authors: Klaas R. WesterterpAbstract:Inter-individual variation in Energy Expenditure is mainly a function of differences in body size and physical activity. Intra-individually, the Energy Expenditure associated with physical activity, i.e. muscular contractions to perform body postures and -movements, is the most variable component of total Energy Expenditure. Determinants of activity associated Energy Expenditure (AEE), as derived from observational and intervention studies are presented. Twin studies showed that most of the between subject variation in AEE is explained by genetic factors. AEE of subjects in the confined environment of a respiration chamber was on average halve the value as observed in the same subjects in free-living conditions with doubly labeled water. In young adults, non-training activity was not affected by exercise training. However, in elderly subjects, exercise training induced an equivalent compensatory decline in non-training activity. Similarly, AEE was reduced during Energy restriction and in patients with chronic disease increasing resting Energy Expenditure. Studies with exercise training showed the reduction is difficult to overcome.
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Physical activity as a determinant of total Energy Expenditure in critically ill children.
Clinical nutrition (Edinburgh Scotland), 2007Co-Authors: Martijn Van Der Kuip, Klaas R. Westerterp, Kees De Meer, Reinoud J. B. J. GemkeAbstract:BACKGROUND & AIMS: For adequate nutritional support of critically ill children, knowledge of the patient's Energy Expenditure is required. Steady state measurement by a metabolic monitor are defined as resting Energy Expenditure and may underestimate total Energy Expenditure in clinical practise. The aim of this study was to investigate total Energy Expenditure, resting Energy Expenditure and the relation with physical activity during critical illness and initial recovery. METHODS: We enrolled 20 patients (0-16 yr) with sepsis or following surgery. During the first week following admission, total Energy Expenditure was measured with doubly labelled water, and compared with daily resting Energy Expenditure measurements (metabolic monitor). Activity levels were independently determined by tri-axial accelerometry. RESULTS: Resting Energy Expenditure was not different from Schofield's predicted basal metabolic rate, but was 20% lower than total Energy Expenditure (P=0.006). Overall physical activity level (=total Energy Expenditure divided by resting Energy Expenditure) was 1.22 (95%CI: 1.08-1.36) and activity related Energy Expenditure (=total Energy Expenditure minus resting Energy Expenditure) was associated with accelerometry recordings (R(2)=0.72, P=0.02). CONCLUSIONS: During the week following pediatric intensive care admission, in the individual critically ill patient, activity related Energy Expenditure should be taken into account to prevent a negative Energy balance.
Michael I. Goran - One of the best experts on this subject based on the ideXlab platform.
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Serum Leptin and Energy Expenditure in Children
The Journal of clinical endocrinology and metabolism, 1997Co-Authors: Tim R. Nagy, Barbara A. Gower, Richard M. Shewchuk, Michael I. GoranAbstract:Leptin has been hypothesized to play an important role in Energy balance by affecting both Energy intake and Energy Expenditure. The purpose of our study was to determine the relationship between fasting serum leptin concentrations and measures of Energy Expenditure in prepubertal children. We measured total Energy Expenditure (TEE; by the doubly labeled water technique), resting Energy Expenditure (REE; after an overnight fast), activity Energy Expenditure (AEE; TEE − REE), body composition (by dual Energy x-ray absorptiometry), and fasting serum leptin concentration (by RIA) in 76 children. Simple correlations showed that all measures of Energy Expenditure (TEE, REE, and AEE) were positively related to the serum leptin concentration (r = 0.50, P < 0.001; r = 0.45, P < 0.001; and r = 0.30, P < 0.01, respectively). However, after adjusting for body composition (fat-free mass and fat mass), gender, and ethnicity, serum leptin concentrations were not related to any measure of Energy Expenditure (TEE, P = 0....
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Genetic influences on human Energy Expenditure and substrate utilization.
Behavior Genetics, 1997Co-Authors: Michael I. GoranAbstract:Understanding the genetic factors of obesity requires consideration of the genetic basis of the underlying etiological factors including Energy Expenditure and substrate utilization. Genetic susceptibility studies suggest that altered Energy Expenditure and/or preferential substrate utilization are likely to be involved in the etiology of obesity. Twin and family studies suggest that there is a strongly heritable component to resting Energy Expenditure, substrate utilization, and the thermic response to feeding. Physical activity Energy Expenditure has been less well studied; new data are presented in young sib pairs that suggest moderate heritability of nonresting Energy Expenditure. Only a few candidate gene studies have been performed to examine the role of basic proteins involved in Energy Expenditure (the sodium–potassium ATPase and the uncoupling protein) or substrate utilization (fatty acid binding protein). The lack of information in this area warrants further investigation into genetic aspects of Energy and substrate metabolism.
James A. Levine - One of the best experts on this subject based on the ideXlab platform.
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activity promoting video games and increased Energy Expenditure
The Journal of Pediatrics, 2009Co-Authors: Lorraine Lanninghamfoster, Randal C Foster, Shelly K Mccrady, Teresa B Jensen, Naim Mitre, James A. LevineAbstract:Objectives To test the hypothesis that both children and adults would expend more calories and move more while playing activity-promoting video games compared with sedentary video games. Study design In this single-group study, 22 healthy children (12 ± 2 years; 11 male, 11 female) and 20 adults (34 ± 11 years; 10 male, 10 female) were recruited. Energy Expenditure and physical activity were measured while participants were resting, standing, watching television seated, sitting and playing a traditional sedentary video game, and while playing an activity-promoting video game (Nintendo Wii Boxing). Physical activity was measured with accelerometers, and Energy Expenditure was measured with an indirect calorimeter. Results Energy Expenditure was significantly greater than all other activities when children or adults played Nintendo Wii (mean increase over resting, 189 ± 63 kcal/hr, P P P Conclusion Activity-promoting video games have the potential to increase movement and Energy Expenditure in children and adults.
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Measurement of Energy Expenditure.
Public health nutrition, 2005Co-Authors: James A. LevineAbstract:Measurement of Energy Expenditure in humans is required to assess metabolic needs, fuel utilisation, and the relative thermic effect of different food, drink, drug and emotional components. Indirect and direct calorimetric and non-calorimetric methods for measuring Energy Expenditure are reviewed, and their relative value for measurement in the laboratory and field settings is assessed. Where high accuracy is required and sufficient resources are available, an open-circuit indirect calorimeter can be used. Open-circuit indirect calorimeters can employ a mask, hood, canopy or room/chamber for collection of expired air. For short-term measurements, mask, hood or canopy systems suffice. Chamber-based systems are more accurate for the long-term measurement of specified activity patterns but behaviour constraints mean they do not reflect real life. Where resources are limited and/or optimum precision can be sacrificed, flexible total collection systems and non-calorimetric methods are potentially useful if the limitations of these methods are appreciated. The use of the stable isotope technique, doubly labelled water, enables total daily Energy Expenditure to be measured accurately in free-living subjects. The factorial method for combining activity logs and data on the Energy costs of activities can also provide detailed information on free-living subjects.
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Variability in Energy Expenditure and its components.
Current opinion in clinical nutrition and metabolic care, 2004Co-Authors: William T. Donahoo, James A. Levine, Edward L. MelansonAbstract:Purpose of reviewTo review factors contributing to variation in total daily Energy Expenditure and its primary components: (1) resting metabolic rate; (2) diet-induced thermogenesis; and (3) activity thermogenesis, including exercise Energy Expenditure and nonexercise activity. For each component, t
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Energy Expenditure of nonexercise activity
The American journal of clinical nutrition, 2000Co-Authors: James A. Levine, Sara J Schleusner, Michael D. JensenAbstract:BACKGROUND We found recently that changes in nonexercise activity thermogenesis (NEAT) mediate resistance to weight gain with overfeeding in sedentary adults. A potentially important, yet seldom investigated, component of NEAT is the Energy Expenditure of fidgeting-like activities. OBJECTIVE Our goal was to measure changes in Energy Expenditure with fidgeting-like activities. DESIGN Energy Expenditure was measured in 24 subjects (17 women and 7 men x+/- SD body weight: 76 +/- 21 kg) while recumbent at rest, sitting motionless, standing motionless, partaking of self-selected fidgeting-like movements while seated and while standing, and walking on a treadmill at 1.6, 3.2, and 4.8 km/h (1, 2, and 3 mph). Measurements were performed by using a high-precision, indirect calorimeter connected to the subject via a transparent, lightweight facemask that enabled almost unrestricted movement. RESULTS Compared with metabolic rate in the supine position (5.4 +/- 1.5 kJ/min), Energy Expenditure increased while sitting motionless by 4 +/- 6%, while fidgeting while seated by 54 +/- 29% (P: < 0.0001), while standing motionless by 13 +/- 8% (P: < 0.0001), while fidgeting while standing by 94 +/- 38% (P: < 0.0001), while walking at 1.6 km/h by 154 +/- 38% (P: < 0.0001), while walking at 3.2 km/h by 202 +/- 45% (P: < 0.0001), and while walking at 4.8 km/h by 292 +/- 81% (P: < 0.0001). There was a significant, positive correlation between changes in Energy Expenditure and body weight for fidgeting-like activities while standing (r = 0.43, P: = 0.02) but not while seated. CONCLUSIONS There is marked variance between subjects in the Energy Expenditure associated with self-selected fidgeting-like activities. The thermogenic potential of fidgeting-like and low-grade activities is sufficiently great to substantively contribute to Energy balance.
A Tremblay - One of the best experts on this subject based on the ideXlab platform.
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Genetic influences on Energy Expenditure in humans
Critical reviews in food science and nutrition, 1993Co-Authors: Claude Bouchard, Louis Pérusse, Olivier Dériaz, Jean-pierre Després, A TremblayAbstract:Variations in human Energy Expenditure are partly because of an influence of the genotype, even after control for the well-established concomitants of Energy Expenditure. Using the techniques of genetic epidemiology, we have found that about 40% of the variance in resting metabolic rate, thermic effect of food, and Energy cost of low-to-moderate intensity exercise (< or = 5 times the resting metabolic rate) is explained by inherited characteristics. A significant genetic effect has also been reported for the level of habitual physical activity. The existence of a genotype-environment interaction has also been investigated. Thus, in response to chronic overfeeding, as well as negative Energy balance, changes in the components of Energy Expenditure exhibit significant identical twin pair resemblance. Nutrient partitioning is emerging as a major determinant of the individual differences in metabolic rate responses to overfeeding or negative Energy balance conditions. Taken as a whole, these observations consistently support the hypothesis that heredity plays a significant role in the various components of Energy Expenditure in humans.
Stephen R Bloom - One of the best experts on this subject based on the ideXlab platform.
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Oxyntomodulin analogue increases Energy Expenditure via the glucagon receptor.
Peptides, 2018Co-Authors: Rebecca Scott, James Minnion, Tricia Tan, Stephen R BloomAbstract:The gut hormone oxyntomodulin (OXM) causes weight loss by reducing appetite and increasing Energy Expenditure. Several analogues are being developed to treat obesity. Exactly how oxyntomodulin works, however, remains controversial. OXM can activate both glucagon and GLP-1 receptors but no specific receptor has been identified. It is thought that the anorectic effect occurs predominantly through GLP-1 receptor activation but, to date, it has not been formally confirmed which receptor is responsible for the increased Energy Expenditure. We developed OX-SR, a sustained-release OXM analogue. It produces a significant and sustained increase in Energy Expenditure in rats as measured by indirect calorimetry. We now show that this increase in Energy Expenditure occurs via activation of the glucagon receptor. Blockade of the GLP-1 receptor with Exendin 9-39 does not block the increase in oxygen consumption caused by OX-SR. However, when activity at the glucagon receptor is lost, there is no increase in Energy Expenditure. Glucagon receptor activity therefore appears to be essential for OX-SR's effects on Energy Expenditure. The development of future 'dual agonist' analogues will require careful balancing of GLP-1 and glucagon receptor activities to obtain optimal effects.
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Gastric Bypass Increases Energy Expenditure in Rats
Gastroenterology, 2009Co-Authors: Marco Bueter, Stephen R Bloom, Christian Löwenstein, Torsten Olbers, Maggie Wang, Nina L. Cluny, Keith A. Sharkey, Thomas A. Lutz, Carel W. Le RouxAbstract:Background & Aims Mechanisms underlying weight loss maintenance after gastric bypass are poorly understood. Our aim was to examine the effects of gastric bypass on Energy Expenditure in rats. Methods Thirty diet-induced obese male Wistar rats underwent either gastric bypass (n = 14), sham-operation ad libitum fed (n = 8), or sham-operation body weight-matched (n = 8). Energy Expenditure was measured in an open circuit calorimetry system. Results Twenty-four-hour Energy Expenditure was increased after gastric bypass (4.50 ± 0.04 kcal/kg/h) compared with sham-operated, ad libitum fed (4.29 ± 0.08 kcal/kg/h) and sham-operated, body weight-matched controls (3.98 ± 0.10 kcal/kg/h, P P P P Conclusions Gastric bypass in rats prevented the decrease in Energy Expenditure after weight loss. Diet-induced thermogenesis was higher after gastric bypass compared with body weight-matched controls. Raised Energy Expenditure may be a mechanism explaining the physiologic basis of weight loss after gastric bypass.
