Low Levels Of Energy Expenditure Research Articles

Sedentary behaviour levels in adults with an intellectual disability: a systematic review and meta-analysis

Background: Sedentary behaviour (SB), which is characterised by low levels of energy expenditure, has been linked to increased cardio-metabolic risks, obesity and mortality, as well as cancer risk. No firm guidelines are established on safe levels of SB. Adults with an intellectual disability (ID) have poorer health than their counterparts in the general population with higher rates of multi-morbidity, inactivity, and obesity. The reasons for this health disparity are unclear however it is known that SB and overall inactivity contribute to poorer health. There is no clear picture of the levels of SB among individuals with ID therefore SB levels in this vulnerable population need to be examined. The aim of this systematic review is to investigate the prevalence of sedentary behaviour in adults with an ID. Methods: The PRISMA-P framework was applied to identify high quality articles. An extensive search was carried out in four databases and grey literature sources . In total, 1,972 articles were retrieved of which 48 articles went forward for full review after duplicate removal and screening by title and abstract. The National Institute of Health’s quality assessment tools were used to assess article quality. Two reviewers independently assessed each article. An excel spreadsheet was created to guide the data extraction process. The final review included 25 articles. A meta-analysis was completed using REVMAN. Results: Different SB assessment types were identified in studies. These included steps, time, questionnaires, and screen time. Studies were heterogeneous. Observed daily steps per individual ranged from 44 to above 30,000, with an average of approximately 6,500 steps. Mean daily time spent in SBs was more than 60% of available time, with observed screen time of more than 3 hours. Conclusion: There is a high prevalence of SB in adults with an intellectual disability. [Registration no: Index CRD42020177225].

Sedentary behaviour levels in adults with an intellectual disability: a systematic review and meta-analysis

Background:Sedentarybehaviour(SB),which is characterised by low levels of energy expenditure,has been linked toincreased cardio-metabolic risks, obesityandmortality, as well as cancer risk.Nofirm guidelinesareestablished on safe levels ofSB. Adults with an intellectual disability(ID)have poorer health than their counterparts in the general population with higher rates of multi-morbidity, inactivity, and obesity. The reasons for this health disparity are unclearhowever it is known thatSBand overall inactivity contribute to poorer health.There is no clear picture of the levels of SB among individuals with ID therefore SBlevels in this vulnerable population need to beexamined.The aim of thissystematic reviewistoinvestigate the prevalence of sedentary behaviour in adults with anID. Methods:The PRISMA-P framework was applied to identify high quality articles. An extensive search was carried out in four databasesand grey literaturesources.In total,1,972 articleswere retrieved of which48 articles went forward for full review after duplicate removal and screening by title and abstract.The National Institute of Health's quality assessment tools were used to assess article quality. Tworeviewers independently assessed each article. An excel spreadsheetwas created to guide thedata extractionprocess.Thefinalreview included25 articles.A meta-analysis was completed using REVMAN. Results:DifferentSBassessment types were identifiedinstudies. Theseincludedsteps, time, questionnaires, and screen time. Studies were heterogeneous.Observeddaily stepsper individualranged from44toabove30,000, with an average of approximately 6,500 steps. Mean daily time spent inSBswas more than 60%of available time,with observed screen time of more than 3 hours. Conclusion:There is a high prevalence ofSBin adultswith an intellectual disability. [Registration no: Index CRD42020177225].

Effects of Circuit Weight-Interval Training on Physical Fitness, Cardiac Autonomic Control, and Quality of Life in Sedentary Workers.

Sedentary behaviors, those that involve sitting and low levels of energy expenditure, have been associated with several adverse cardiometabolic effects. This study evaluated the chronic effects of a combined circuit weight interval training (CWIT) on physical fitness, quality of life, and heart rate variability (HRV), and compared the effects of CWIT-induced autonomic adaptations on different postures in adult sedentary workers. Twenty-seven sedentary workers (age 36.9 ± 9.2 years old, 13 men and 14 women) were divided into two groups: control, who continued their sedentary behavior, and experimental, who were submitted to a CWIT for 12 weeks, completing two ~40 min sessions per week. Monitoring of 8th, 16th, and 24th sessions revealed a moderate training load during sessions. Participants exhibited an improved aerobic capacity (VO2max, 34.03 ± 5.36 vs. 36.45 ± 6.05 mL/kg/min, p < 0.05) and flexibility (22.6 ± 11.4 vs. 25.3 ± 10.1 cm, p < 0.05) after the training period. In addition, they showed greater quality of life scores. However, the CWIT did not change body composition. Interestingly, more HRV parameters were improved in the seated position. The CWIT used in the current study was associated with improvements in several fitness and quality of life parameters, as well as in cardiac autonomic control of HR in adult sedentary workers. Examination of different body positions when evaluating changes in HRV appears to be a relevant aspect to be considered in further studies. Future randomized controlled trials (RCTs) with larger samples of both sexes should confirm these promising results.

Abstract P125: Multiple Measures of Energy Expenditure and Substrate Oxidation in Non-obese White and African American Young Adults

Introduction: African Americans (AA) experience higher rates of obesity and related disorders than the general U.S. population. It has been hypothesized that the increased risk of obesity among AA may be explained, in part, by lower levels of energy expenditure (EE) and lower levels of fat oxidation. However, many different measures of EE and substrate oxidation have been employed across previous studies. Objective: The objective of this study was to compare multiple measures of EE and substrate oxidation among White (W) and AA adults. We hypothesize that AA will have lower EE and lower fat oxidation rates than W. Methods: A sample of 12 young (ages 22 to 35 y), non-obese AA adults was recruited from the local community and pair-matched by age, sex and body mass index (BMI) to a sample of 12 W adults. Height and weight were measured and BMI was calculated (kg/m 2 ). Total fat mass (FM) and fat free mass (FFM) were measured using dual energy x-ray absorptiometry. Resting EE (REE) and respiratory quotient (RQ) were measured in a fasting state using a metabolic cart; 24-hour EE, 24-h RQ, sleep EE and sleep RQ were measured in a whole room calorimeter; and free-living total daily EE (TDEE) was measured over two weeks using doubly labelled water. Physical activity level (PAL) was computed as TDEE/REE. Differences between W and AA were determined using general linear models, adjusting for FFM. Results: The analytic sample had a mean age of 27.0 y (SD 4.3 y) and mean BMI of 22.9 kg/m 2 (SD 2.9 kg/m 2 ). There were no significant differences in age, BMI, FM or FFM between W and AA (all p&gt;0.05). However, W had significantly higher REE (1459 vs 1305 kcal/day; p=0.001), 24-h EE (1826 versus 1737 kcal/day; p=0.02), sleep EE (1509 vs 1405 kcal/day; p=0.005); but not TDEE (2452 vs 2313 kcal/day; p=0.30) compared to AA. There were no race differences in RQ (0.83 vs 0.83; p=0.93), 24-h RQ (0.86 vs 0.88; p=0.24) or sleep RQ (0.86 vs 0.87; p=0.44). On the other hand, AA had higher PAL (1.34 vs 1.26; p=0.04) compared to W. Conclusions: Non-obese W adults demonstrated higher REE, 24-h EE, and sleep EE compared to AA, but had similar levels of free-living TDEE. It appears as though some AA adults may compensate for lower REE by increased physical activity, which may be an effective strategy to prevent weight gain and obesity.

Physical Activity and Sedentary Behavior Relative to Body Mass Index among School Children in Saudi Arabia

Background: Increased time spent on sedentary activities and decreased time spent on physical activities has been linked with lower levels of energy expenditure, overweight, obesity, and increased risk of cardiovascular and metabolic diseases. During the past few years, rapid improvements in living standards, mechanization and urbanization has a profound impact in the Kingdom of Saudi Arabia resulting in low levels of physical activity and sedentary living. Therefore the purpose of the research is to provide basic data of subjectively measured physical activity and sedentary behavior of the Saudi school children in relation with BMI. Methods: This study used cross sectional survey of 357 school children aged 10-16 years (82 boys and 275 girls) recruited from different schools in central Riyadh between 2015 and 2016. Demographic information such as age, gender, weight, height was obtained from each participant. Sedentary behavior was recorded as time spent on activities such as TV viewing, playing video games, computer use and homework, and physical activity was assessed using Physical Activity Questionnaire for Children (PAQ-C), and Godin leisure- time exercise questionnaire. Results: Majority of participants were girls (77%). Values of body fat expressed as percentiles of body mass index of appropriate age and height were used as criteria to stratify the sample. The sample proportion stratified based on percentile of body weight constituted of 5.3% of underweight (19), 54.6% of normal (195), 18.8% of overweight (67) and 23% of obese (76) children. A high proportion (68.3%) of Saudi school children spent more than 2 hours on screen time (TV+PC) daily. PAQ-C reported 26.3% are less active, 51.5% are moderately active and 22.1% are highly active. Using ANOVA, no significant variation was shown in PAQ-C scores in relation to BMI. PA findings by Godin leisure-time exercise questionnaire concluded that 70.3% are insufficiently active, 20.4% are moderately active and 9.2% are active. Analysis done by Kruskal-Wallis test showed significant difference observed in Godin moderate scores (P=0.01) and total scores (P=0.03) but not in other subcategories (strenuous, mild, Sweat) in relation to BMI. Conclusion: Sedentary behaviors, physical inactivity and increased BMI among Saudi school children are the major public health concerns. There is an urgent need for national policy promoting active living and healthy eating and reducing sedentary behaviors among children in Saudi Arabia.

Role of physical activity in regulating appetite and body fat

Recent articles in the press have questioned the role of physical activity in regulating appetite and controlling bodyweight. These articles can be confusing and misleading for the public. Yet this is a complex area and there is disagreement about the importance of physical activity even among academics. Uncertainty and misunderstanding in this area may be related to the heterogeneity of the term ‘physical activity’ which encompasses sporting pursuits with extremely high levels of energy expenditure over prolonged periods of time, as well as everyday tasks involving much lower levels of energy expenditure on an intermittent basis. This latter form of physical activity includes what has been termed ‘non-exercise activity thermogenesis’ (NEAT). In the right circumstances, physical activity can make a major contribution to the maintenance of a healthy weight even in the absence of dietary control although a combination of the two is almost certain to be more effective. In the long-term, evidence suggests that for most people exercise is likely to lead to only modest weight loss. This may be due to an insufficient amount of physical activity being performed together with compensatory changes in eating and exercise behaviours. This is hard to prove because energy intake and energy expenditure are difficult to quantify in free-living situations. Individual differences in the way people respond to exercise due to both environmental (e.g. social class, education level, income, eating and exercise behaviours of family and peers, weather etc.) and genetic factors also contribute to uncertainty about the effectiveness of physical activity for weight control. Nevertheless, physical activity remains a vital component of a healthy lifestyle due to its positive influence on energy balance as well as its potential to reduce the risk of lifestyle-related diseases.

High energy expenditure is not protective against increased adiposity in children.

Low levels of energy expenditure (TEE) may contribute to excess weight during childhood, but limited longitudinal data exist. This is to test whether low TEE during the first 6 years of life could predict excess weight status at 8 years. Total energy expenditure from doubly labelled water, weight, stature, waist circumference and fat mass and fat-free mass (FFM) in children at 0.25, 2, 4 and 6 years of age. This cohort includes individuals at high (n = 27) and low risk (n = 26) for childhood obesity, based upon whether pre-pregnant maternal obesity. A linear mixed effects model was fit to TEE. Individual variation was accounted for as a random effect. Residual TEE was calculated for age and individually averaged across time. Fat-free mass (kg) was highly correlated (R2 = 0.91) with TEE (kcal/day), and waist circumference and sex were also significant predictors of TEE. TEE residual tracked within individuals. TEE residuals did not correlate with either BMI or %fat at age 8 years. Using the residual TEE approach to identify high and low TEE during the first 6 years of life did not explain excess weight at 8 years of life in this cohort of children at high and low risk of obesity based upon maternal obesity status.

Low Levels of Energy Expenditure in Childhood Cancer Survivors

Childhood cancer survivors are at an increased risk of obesity but causes for this elevated risk are uncertain. We evaluated total energy expenditure in childhood cancer survivors using the doubly labeled water method in a cross-sectional study of 17 survivors of pediatric leukemia or lymphoma (median age, 11.5 y). Mean total energy expenditure was 2073 kcal/d, which was nearly 500 kcal/d lower than estimated energy requirements with recommended levels of physical activity. This energy gap is likely to contribute to the risk of obesity in this population and future trials are needed to assess implications and potential treatment strategies.

Abstract P128: A New Device for Objective Measurement of Sedentary Behavior

Objective measurement of sedentary behavior with accelerometers is an important part of epidemiological research. Unfortunately, the definition of sedentary behavior includes both “sitting and low levels of energy expenditure”, which are not usually measured by popular activity monitors. Currently, there is only one research device (ActivPAL) that can objectively measure both body posture and activity for sedentary behavior classification. The purpose of this study was to compare the Lumoback device, a commercial accelerometer-based posture monitor, for sedentary measurement during daily activities to the ActivPAL. The Lumoback also has real-time feedback delivered to the user through their mobile device, which may prove to be instrumental in sedentary intervention research. Subjects (N=33) wore the Lumoback and ActivPAL devices simultaneously during waking hours while continuing with their normal activity patterns. Linear regression showed good correlation between sitting minutes (R2=0.89, p &lt; 0.001) and standing minutes (R2=0.86, p &lt; 0.001) from the devices. There was no significant difference (p &gt; 0.05) between the seconds of sedentary behavior measured with the lumoback and seconds sitting/lying measured with the ActivPAL. The lumoback posture monitor was similar to the ActivPAL for measurement of sedentary behavior, and could be used to measure sedentary behavior over the course of a waking day.

What is Causing the Worldwide Rise in Body Weight?

The worldwide rise in body weight has reached epidemic proportions and this has serious public health consequences. Despite the universal recognition of this problem, its causes are still debated: some attribute it to excess caloric intake; others blame a lack of physical activity (PA); some implicate specific changes to micro- and macro-nutrients. During the past century, government health agencies have developed guidance on healthy eating. These, along with advances in agriculture and food manufacturing, have largely eliminated nutrient deficiencies and helped reduce the consumption of fat. Over the past 60 years, however, technological advances and shifts in the types of occupations prominent in industrialized as well as developing countries have resulted in well-documented decreases in energy expenditure. Energy intake must be balanced with energy expenditure in order to prevent weight gain, and there is increasing evidence that this balance must be at a relatively high level of energy flux. A program that was started in São Paulo in 1996 known as ‘Agita’ has sought to motivate populations to engage in small amounts of physical exercise daily to tackle growing obesity levels. This multi-agency initiative is one example of how to successfully increase exercise within a community and scale both within (e.g. all states in Brazil) and across many nations. Reducing caloric intake in whole populations is challenging especially at relatively low levels of energy expenditure, and evidence suggests that there is a critical energy flux threshold for regulating intake to achieve energy balance. Increasing PA, however, may be more achievable than reducing intake. Activity raises caloric expenditure and can offset excess intake. The implementation of programs to achieve greater PA is therefore vital if the worldwide rise in body weight is to be halted, while we also need to implement programs to help people eat smarter.

What is Causing the Worldwide Rise in Body Weight?

The worldwide rise in body weight has reached epidemic proportions and this has serious public health consequences. Despite the universal recognition of this problem, its causes are still debated: some attribute it to excess caloric intake; others blame a lack of physical activity (PA); some implicate specific changes to micro- and macro-nutrients. During the past century, government health agencies have developed guidance on healthy eating. These, along with advances in agriculture and food manufacturing, have largely eliminated nutrient deficiencies and helped reduce the consumption of fat. Over the past 60 years, however, technological advances and shifts in the types of occupations prominent in industrialised as well as developing countries have resulted in well-documented decreases in energy expenditure. Energy intake must be balanced with energy expenditure in order to prevent weight gain, and there is increasing evidence that this balance must be at a relatively high level of energy flux. A programme that was started in São Paulo in 1996 known as 'Agita' has sought to motivate populations to engage in small amounts of physical exercise daily to tackle growing obesity levels. This multi-agency initiative is one example of how to successfully increase exercise within a community and scale both within (e.g. all states in Brazil) and across many nations. Reducing caloric intake in whole populations is challenging especially at relatively low levels of energy expenditure, and evidence suggests that there is a critical energy flux threshold for regulating intake to achieve energy balance. Increasing PA, however, may be more achievable than reducing intake. Activity raises caloric expenditure and can offset excess intake. The implementation of programmes to achieve greater PA is therefore vital if the worldwide rise in body weight is to be halted, while we also need to implement programmes to help people eat smarter.

Evaluation of N95 Respirator Use with a Surgical Mask Cover: Effects on Breathing Resistance and Inhaled Carbon Dioxide

For pandemic influenza outbreaks, the Institute of Medicine has recommended using a surgical mask cover (SM) over N95 filtering facepiece respirators (FFRs) among healthcare workers as one strategy to avoid surface contamination of the FFR which would extend its efficacy and reduce the threat of exhausting FFR supplies. The objective of this investigation was to measure breathing air quality and breathing resistance when using FFRs with US Food and Drug Administration-cleared SM and without SM. Thirty National Institute for Occupational Safety and Health (NIOSH)-approved FFR models with and without SM were evaluated using the NIOSH Automated Breathing and Metabolic Simulator (ABMS) through six incremental work rates. Generally, concentrations of average inhaled CO(2) decreased and average inhaled O(2) increased with increasing O(2) consumption for FFR+SM and FFR-only. For most work rates, peak inhalation and exhalation pressures were statistically higher in FFR+SM as compared with FFR-only. The type of FFR and the presence of exhalation valves (EVs) had significant effects on average inhaled CO(2), average inhaled O(2), and breathing pressures. The evidence suggests that placement of an SM on one type of FFR improved inhaled breathing gas concentrations over the FFR without SM; the placement of an SM over an FFR+EV probably will prevent the EV from opening, regardless of activity intensity; and, at lower levels of energy expenditure, EVs in FFR do not open either with or without an SM. The differences in inhaled gas concentrations in FFR+SM and FFR-only were significant, especially at lower levels of energy expenditure. The orientation of the SM on the FFR may have a significant effect on the inhaled breathing quality and breathing resistance, although the measurable inhalation and exhalation pressures caused by SM over FFR for healthcare users probably will be imperceptible at lower activity levels.

Youth physical activity and sedentary time and associations with cardiometabolic health

Commentary on: Ekelund U, Luan J, Sherar LB, et al. Moderate to vigorous physical activity and sedentary time and cardiometabolic risk factors in children and adolescents. JAMA 2012;307:704–12.[OpenUrl][1][CrossRef][2][PubMed][3][Web of Science][4]...

An Evidence-Based Review of Exercise and Metabolic Syndrome

An Evidence-Based Review of Exercise and Metabolic Syndrome

Protocol for the modeling the epidemiologic transition study: a longitudinal observational study of energy balance and change in body weight, diabetes and cardiovascular disease risk.

BackgroundThe prevalence of obesity has increased in societies of all socio-cultural backgrounds. To date, guidelines set forward to prevent obesity have universally emphasized optimal levels of physical activity. However there are few empirical data to support the assertion that low levels of energy expenditure in activity is a causal factor in the current obesity epidemic are very limited.Methods/DesignThe Modeling the Epidemiologic Transition Study (METS) is a cohort study designed to assess the association between physical activity levels and relative weight, weight gain and diabetes and cardiovascular disease risk in five population-based samples at different stages of economic development. Twenty-five hundred young adults, ages 25-45, were enrolled in the study; 500 from sites in Ghana, South Africa, Seychelles, Jamaica and the United States. At baseline, physical activity levels were assessed using accelerometry and a questionnaire in all participants and by doubly labeled water in a subsample of 75 per site. We assessed dietary intake using two separate 24-hour recalls, body composition using bioelectrical impedance analysis, and health history, social and economic indicators by questionnaire. Blood pressure was measured and blood samples collected for measurement of lipids, glucose, insulin and adipokines. Full examination including physical activity using accelerometry, anthropometric data and fasting glucose will take place at 12 and 24 months. The distribution of the main variables and the associations between physical activity, independent of energy intake, glucose metabolism and anthropometric measures will be assessed using cross-section and longitudinal analysis within and between sites.DiscussionMETS will provide insight on the relative contribution of physical activity and diet to excess weight, age-related weight gain and incident glucose impairment in five populations' samples of young adults at different stages of economic development. These data should be useful for the development of empirically-based public health policy aimed at the prevention of obesity and associated chronic diseases.

Size Counts: Evolutionary Perspectives on Physical Activity and Body Size From Early Hominids to Modern Humans

This paper examines the evolutionary origins of human dietary and activity patterns, and their implications for understanding modern health problems. Humans have evolved distinctive nutritional characteristics associated the high metabolic costs of our large brains. The evolution of larger hominid brain size necessitated the adoption of foraging strategies that both provided high quality foods, and required larger ranges and activity budgets. Over time, human subsistence strategies have become ever more efficient in obtaining energy with minimal time and effort. Today, populations of the industrialized world live in environments characterized by low levels of energy expenditure and abundant food supplies contributing to growing rates of obesity. Analyses of trends in dietary intake and body weight in the US over the last 50 years indicate that the dramatic rise in obesity cannot be explained solely by increased energy consumption. Rather, declines in activity are also important. Further, we find that recent recommendations on physical activity have the potential to bring daily energy expenditure levels of industrialized societies surprisingly close to those observed among subsistence-level populations. These findings highlight the importance of physical activity in promoting nutritional health and show the utility of evolutionary approaches for developing public health recommendations.

Impaired Control of Body Cooling during Heterothermia Represents the Major Energetic Constraint in an Aging Non-Human Primate Exposed to Cold

Daily heterothermia is used by small mammals for energy and water savings, and seems to be preferentially exhibited during winter rather than during summer. This feature induces a trade-off between the energy saved during daily heterothermia and the energy cost of arousal, which can impact energy balance and survival under harsh environmental conditions. Especially, aging may significantly affect such trade off during cold-induced energy stress, but direct evidences are still lacking. We hypothesized that aging could alter the energetics of daily heterothermia, and that the effects could differ according to season. In the gray mouse lemur (Microcebus murinus), a non-human primate species which exhibits daily heterothermia, we investigated the effects of exposures to 25 and 12°C on body composition, energy balance, patterns of heterothermia and water turnover in adult (N = 8) and aged animals (N = 7) acclimated to winter-like or summer-like photoperiods.Acclimation to summer prevented animals from deep heterothermia, even during aging. During winter, adult animals at 12°C and aged animals at 25°C exhibited low levels of energy expenditure with minor modulations of heterothermia. The major effects of cold were observed during winter, and were particularly pronounced in aged mouse lemurs which exhibited deep heterothermia phases. Body composition was not significantly affected by age and could not explain the age-related differences in heterothermia patterns. However, aging was associated with increased levels of energy expenditure during cold exposure, in concomitance with impaired energy balance. Interestingly, increased energy expenditure and depth of heterothermia phases were strongly correlated.In conclusion, it appeared that the exhibition of shallow heterothermia allowed energy savings during winter in adult animals only. Aged animals exhibited deep heterothermia and increased levels of energy expenditure, impairing energy balance. Thus, an impaired control of the heterothermic process induced high energy costs in the aging mouse lemur exposed to cold.

Impact of a Community-Based Falls Prevention Program on Maintenance of Physical Activity Among Older Adults

This study examines the 9-month impact of a 12-week falls prevention program (called Stand Up!) which included balance exercises and educational components on maintenance of physical activity among community-dwelling seniors. Data were collected among 98 experimental and 102 control participants at baseline, immediately after the program and 9 months later. Involvement in physical activity was measured with three indicators. Program effects were examined using linear and logistic regression procedures. Both groups showed similar increases in weekly frequency of exercise at the 9-month posttest. However, the program's participants showed higher increases in their variety of exercises at the 9-month posttest (especially among those with greater baseline scores). Among seniors reporting lower levels of energy expenditure at baseline, the program's participants showed significantly greater increases in energy expenditure than control participants. These preliminary findings suggest that programs such as Stand Up! have the potential to stimulate continued involvement in physical activity.

Very low levels of energy expenditure among pre-adolescent Mexican-American girls

We assessed activity energy expenditure (AEE) in Mexican-American (MA) and European-American (EA) children. Total energy expenditure (TEE) was measured using the doubly-labeled water method; AEE was calculated as the difference between TEE and resting EE (REE), and physical activity level (PAL) was calculated as TEE/REE. Groups were comparable for age, sex and body mass index (BMI). REE did not differ between groups. The boys did not differ in TEE, AEE, or PAL (MA vs. EA, respectively: TEE, 7.9+/-1.5 vs. 7.5+/-0.9 MJ x d(-1); AEE: 64.9+/-24.7 vs. 65.3+/-22.3 kJ x kg(-1) x d(-1); PAL: 1.57+/-0.18 vs. 1.58+/-0.19 kJ x kg(-1) x d(-1)). MA girls had lower TEE, AEE, and PAL than EA girls (TEE: 6.8+/-0.9 vs. 8.1+/-0.8 MJ x d(-1); AEE, 37.3+/-15.9 vs. 64.9+/-24.7 kJ x kg(-1) x d(-1); PAL, 1.40+/-0.12 vs. 1.57+/-0.18; P <0.005). Results suggest that these MA girls were expending less energy than EA children of comparable body size due to a reduced activity energy expenditure.

Normalization of Energy Expenditure Data for Differences in Body Mass or Composition in Children and Adolescents

The most appropriate model for normalization of energy expenditure (EE) data for body mass or composition in growing children and adolescents has not been studied extensively. In this study, we investigated allometric modeling for the normalization of EE data for body mass or composition in a large cohort of children (n = 833), ages 5-19 y for a wide range of physical activities. Anthropometry was performed by standard techniques, and total body fat-free mass (FFM) and fat mass (FM) were determined by dual-energy X-ray absorptiometry (DXA). Weight status was defined as nonoverweight or overweight based on the 95th percentile for BMI. Total energy expenditure (TEE), basal energy expenditure (BEE), sleeping energy expenditure (SEE), and cycling EE were measured during 24-h room respiration calorimetry. Walking and maximal EE (MaxEE) were measured according to a treadmill protocol. Allometric or power function models were used to identify appropriate scaling parameters for EE. For BEE and lower levels of EE, weight scaled to 0.5. For cycling and treadmill walking/running, the weight exponent approached 0.7. Scaling EE for FFM resulted in exponents of 0.6 for lower rates of EE and 0.8-1.0 for higher rates of EE. Appropriate scaling of EE for body weight and composition of children and adolescents varied primarily as a function of the level of EE. In some instances, the exponents for scaling EE by body weight or composition were influenced by gender and weight status, but not by age.