K R Westerterp

..Intestinal malabsorption probably does not play a role in the energy deficit. Even though the sensation of exertion during climbing at high altitude is intense, the actual energy expenditure is not high...

..Exercise training, as a form of high-intensity activity, affects the physical activity level more in younger subjects than in elderly subjects...

..Obesity results from protracted energy imbalance. Whether this comprises excessive energy intake, lowered physical activity or both, remains disputed...

..Physical inactivity is an important determinant of disability and mortality risk. Even a recent increase in activity level can have an important effect, although the benefits are also easily lost when the activity level is again reduced...

..In men, water turnover was determined by energy intake and physical activity, while seasonal effects appeared through energy expenditure. Women showed a higher water turnover that was unrelated to physical activity...

..Physical activity does not seem to affect the age-induced loss of fat-free mass. However, an active life style has positive effects on muscle function and thus is an important determinant of independent living at old age...

..Is trafficking of dietary fat involved in the development of obesity?..

..Activity energy expenditure is the most variable component of total energy expenditure. It was assessed whether the physical activity level in confined conditions is an indicator of free-living physical activity...

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..The objective was to observe the consequence of the age-associated reduction in physical activity for the maintenance of energy balance as reflected in the fat store of the body...

..Bias in the assessment of dietary intake was analysed from studies comparing reported intake with doubly labelled water assessed energy expenditure...

..The results of the present literature review indicate that eating less is the most effective method for preventing weight gain, despite the potential for a negative effect on physical activity when a negative energy balance is reached...

..In conclusion, it was shown that subjects with higher alcohol consumption are habitually more active. This may explain the lack of increasing body weight through additional energy intake from alcohol...

..5 times resting energy expenditure. Devices for the assessment of physical activity validated using labelled water allow the study of activity patterns and strategies to influence the activity level of a sedentary society...

..However, training might delay the age-induced impairment of personal mobility associated with a reduction in physical activity...

..However, there is still little evidence for this form of adaptive thermogenesis from additional studies. The conclusion is that the fat content has an effect on body fat as a function of the effect of dietary fat on energy intake...

..Exercise induces an increase in fat-free mass, especially in women, and a decrease in fat mass. Women tend to preserve energy balance and consequently loss of fat mass is significantly less...

..It is hypothesized that low dietary fat oxidation makes subjects prone to weight gain...

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..Applications of the two techniques are illustrated with the limits of physical activity and energy expenditure and with activity intensity as a determinant of the physical activity level...

..Validations of methods for the assessment of physical activity and studies on the relation between energy expenditure of activity and obesity were reviewed, with suggestions for further research...

..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...

..Overall insensible water loss was unchanged because the increase in respiratory evaporative water loss was counterbalanced by a decrease in metabolic rate that probably limited the hypoxia-induced increase in ventilation...

..05), reaching a new balance on day 13, 7 d afterward. In conclusion, when in energy balance, lean subjects are capable of adjusting fat oxidation to fat intake within 7 d of when dietary fat content is increased...

..Obesity in Prader-Willi syndrome (PWS) seems to be related to a low basal metabolic rate (BMR). In addition, abnormal sleep patterns reported in PWS might affect sleeping metabolic rate (SMR)...

..An easy and cheap method for validating reported energy intake (EI) is needed...

..The aim of the current study was to assess whether postabsorptive respiratory quotient (RQ) is indicative for the food quotient (FQ), with other factors, such as body composition and energy balance, taken into account...

..To study the effect of body composition on average daily metabolic rate (ADMR) and basal metabolic rate (BMR) in adolescence, and to examine current BMR prediction equations...

..Air-displacement plethysmography (ADP) may be a valid and practical technique to assess body composition in a clinical setting...

..To measure activity related energy expenditure in Prader-Willi syndrome (PWS) corrected for body size...

..05). In conclusion, there is objective evidence that sedentary time and activities related to transportation and commuting, such as walking and bicycling, contribute significantly to the average PAL...

..Thus, trained subjects climbing Mount Everest reached PAL values of 2.0-2.7, well below the observed upper limit at sea level...

..In conclusion, in the studied group of highly motivated lean women, under-reporting of habitual food intake (here due to under-eating) could be eliminated by confrontation with the results of this phenomenon...

..Despite the fact that training in elderly humans improves functional capacity, it appears not to compromise antioxidant defense mechanisms...

..Underreporting of food intake is common in obese subjects...

..In conclusion, appetite suppression and fat oxidation were higher on a high-protein diet without than with carbohydrates exchanged for fat. Energy expenditure was not affected by the carbohydrate content of a high-protein diet...

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..85), and "high" (PAL > 1.85) intensity. It is concluded that the Tracmor can be used in free-living subjects to distinguish among interindividual as well as intraindividual levels of daily physical activity...

..In conclusion, all 3 diets resulted in a successful WM period, while a GMP diet does not improve body weight maintenance and related variables after weight loss compared with a SMP and SSMP diet...

..The effect of interventions (dietary or otherwise) on habitual food intake might be confounded by changes in food-reporting behaviour...

..In conclusion, the increased intake of dietary fat and a decreasing physical activity level are the most important environmental factors explaining the increased prevalence of obesity in westernized societies...

..Data was compared with previously obtained data from a group of younger adults...

..The fact that this correlation exists poses the interesting question of whether the results from a test treatment lasting some weeks could be used to predict the long-term effects of hGH...

..The aim of this study was to compare ADP with deuterium dilution and to investigate the effect of using child-specific prediction equations to correct raw body volume from ADP for thoracic gas volume (TGV) and body surface area (BSA)...

..Objective:To determine whether body composition is related to physical activity in both men and women...

..These results suggest that in healthy, non-obese males the PPARgamma ligand RSG influences TAG metabolism, independent of its PPARgamma transcriptional activity in the subcutaneous adipose tissue...

..To investigate the effect of surgically induced weight loss on energy, substrate and protein metabolism of morbidly obese patients...

..Settings in which these environmental changes can be implemented include the urban and transportation infrastructure, schools, and workplaces.'..

..e., sustaining satiety and energy expenditure and sparing fat-free mass, resulting in energy inefficiency. However, the long-term relationship between net protein synthesis and sparing fat-free mass remains to be elucidated...

..In conclusion, in 60-year-old subjects antioxidant supplementation had no effect on the exercise-induced increase in oxidative stress as measured by free radical products of antipyrine...

..To investigate whether efficiency of weight gain during a short period of overfeeding is related to adaptive differences in basal metabolic rate (BMR) and physical activity...

..For the prevention and treatment of obesity an increase in physical activity is necessary, because (long-term) weight loss or weight maintenance is unlikely to occur when people are as sedentary as most people are today...

..Future studies could develop models to objectively assess activity type and intensity to further increase accuracy of the energy expenditure estimation...

..Plasma pyridoxal and plasma total vitamin B-6 concentrations were not influenced by the amount of protein intake in young and elderly subjects.(ABSTRACT TRUNCATED AT 250 WORDS)..

..Altitude-induced weight loss is mainly caused by malnutrition due to hypoxia-related satiety, independent of acute mountain sickness...

..Both findings are related to GH function and physical activity. BMD, especially in the limbs, tends to be reduced in patients with PWS and is related to GH function...

..70, P<0.001) subjects. The explained variation in AEE by the model was higher than the explained variation by MI alone. This shows that a tri-axial seismic accelerometer is a valid tool for estimating AEE under sedentary conditions...

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..We conclude that exposure to hypobaric hypoxia per se appears to be associated with a change in the attitude toward eating and with a decreased appetite and food intake...

..06 and P<0.01, respectively). In conclusion, Muscle(FTD) probably cannot explain why some people are more prone to engaging in physical activities than others...

..These results suggest that knowledge about the individual physical activity level is necessary for the estimation of the energy need of the COPD patient...

..CONCLUSION: Physically active older adults have a reduced exercise-induced oxidative stress than older adults with a lower level of physical activity. It seems that regular physical activity improves the antioxidant defense capacity...

..The postprandial responses in (an)orexigenic hormones and feelings of hunger are characterized by large inter-individual differences. Food intake regulation was shown earlier to be partly under genetic control...

..Reference data for physical activity level (PAL) and activity-related energy expenditure (AEE) are needed for a better understanding of the effect of activity on childhood health, growth and development..

..Accelerometry was used to assess the relationship between the physical activity level (PAL) and time spent on activities of various intensities in children...

..In the present study, activity patterns of GH-treated children were measured and compared to those of healthy controls...

..To compare resting energy expenditure (REE) between Asians and whites after adjusting for fat-free mass measured with a two- or more-compartment model...

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..Thus an active lifestyle may help to maintain or improve mitochondrial capacity...

..Habitual meal frequency was a function of components of EE, namely resting EE and activity-induced EE, only in subjects with a medium to high FFM (men). FFM-related differences in these relationships suggest a role of physical activity...

..This cannot be explained by (possible) differences found in TRP concentrations and TRP:LNAA ratios in the breakfasts and in plasma, as well as in circulating total amino acids, GLP-1 and ghrelin...

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..The results suggest that a difference in appetite ratings between types of protein appears when certain amino acids are above and below particular threshold values...

..The circannual rhythm in SMR could not be explained by changes in body composition, thyroid activity, or leptin. Interindividual variation in SMR was explained by fat-free mass (P < 0.001) and leptin (P < 0.001)...

..The role of dietary protein in short term satiety is of interest with respect to body weight regulation...

..For this purpose, however, non-fasting subjects must be excluded and a regular function check of the ventilated-hood system is recommendable...

..In addition, long-term use of casein may contribute to preservation of fat-free mass...

..The common rs9939609 single nucleotide polymorphism (SNP) in the fat mass and obesity-associated (FTO) gene is associated with adiposity, possibly by affecting satiety responsiveness...

..The aim of this study was to develop models for the detection of type, duration, and intensity of human physical activity using one triaxial accelerometer...

..High-protein diets have been shown to increase energy expenditure (EE)...

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..Maximum GH concentrations found during endocrine tests were not significantly different between good and poor responders. Changes in body composition data, after 6 wk, proved valuable in identifying good responders to GH therapy...

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..An increase in the protein content of a diet results in an increase in satiety and energy expenditure. It is not clear to what extent a specific type of protein has such effects...

..156 x 10(-5) x Tracmor2 average counts day(-1) + 0.978 (r=0.79, P<0.01). In conclusion, Tracmor2 is a valid instrument to measure physical activity in children under free-living conditions...

..We hypothesized that the combined use of accelerometry and HR monitoring, under daily life conditions, could provide a good estimate of physical fitness...

..We investigated if the PPARgamma ligand rosiglitazone influences substrate usage, energy expenditure (EE) and energy intake (EI) and, thereby, how PPARgamma activity contributes to susceptibility to obesity...

..To investigate the ability of a newly developed triaxial accelerometer to predict total energy expenditure (EE) (TEE) and activity-related EE (AEE) in free-living conditions...

..To study whether there are any negative or positive effects of 6 months of increased fluid intake in reasonably healthy elderly men...

..06 (SD 0.09) for elderly which was also different from 1.00 (P<0.001). For adults, BMR is an appropriate measure of OMR. In children, the use of BMR to estimate OMR would introduce an overestimate and for elderly an underestimate...

..Furthermore, the sympathetic nervous system is involved in the regulation of lipolysis, and the sympathetic innervation of white adipose tissue may play an important role in the regulation of total body fat in general...

..We recently reported on a new method to assess physical fitness, based on the combined use of accelerometry and heart rate (HR) registration. This study tested the validity of the prediction formula in a group of healthy young adults...

..To compare overweight and lean subjects with respect to thermogenesis and physiological insulation in response to mild cold and rewarming...

..A genetic control of activity-induced energy expenditure (AEE) may contribute to a genetic susceptibility to obesity...

..39, P=0.007). In conclusion, subjects with a relatively large heat production during cold exposure maintained a relatively high skin temperature but showed a short NSI, independent of differences in body composition...

..However, the validity of the questionnaire remains to be established in males, other age groups, and populations of lower educational levels...

..It is advised to measure SMR based on minimum residual EE during nights following free-living conditions, and to exclude EE measures 1 h before awakening from SMR and OMR calculations to prevent influences of habitual wake-up time...

..The impact of season on energy expenditure and physical activity is not well quantified. This study focused on summer-winter differences in total energy expenditure (TEE) and physical activity...