Differences of energy expenditure and physical activity patterns in subjects with various degrees of obesity

Measured vs estimated resting energy expenditure in children and adolescents with obesity

Pediatric obesity requires early targeted interventions consisting mainly of a low-calorie diet prescribed based on resting energy expenditure (REE), often estimated through predictive equations. The aim of this study was to define the prevalence of "hypo-", "normo-" and "hypermetabolic" in a large cohort of children and adolescents with obesity by comparing measured and estimated REE and to evaluate the characteristics related to these metabolic statuses in both males and females. The study population was divided into the three subgroups by comparing REE measured using indirect calorimetry and estimated using the Molnar equation, and subsequently analyzed. The majority of the participants (60.6%) were normometabolic, 25.5% hypermetabolic and 13.9% hypometabolic. No significant differences in age, Tanner stage, systolic blood pressure, or the presence of metabolic syndrome were found. However, the hypermetabolic subgroup was significantly lighter, shorter, with lower hip and waist circumferences, had a greater amount of fat-free mass and lower fat mass, significantly lower diastolic blood pressure, and a significantly higher frequency of non-alcoholic liver steatosis. Pediatric obesity is more associated with normal or increased REE than with a hypometabolic condition, suggesting that estimation of energy expenditure with predictive equations is still inadequate for prescribing the appropriate diet plan.

Hepatic protein kinase Cbeta deficiency mitigates late-onset obesity

Although aging is associated with progressive adiposity and a decline in liver function, the underlying molecular mechanisms and metabolic interplay are incompletely understood. Here, we demonstrate that aging induces hepatic protein kinase Cbeta (PKCβ) expression, while hepatocyte PKCβ deficiency (PKCβHep-/-) in mice significantly attenuates obesity in aged mice fed a high-fat diet. Compared with control PKCβfl/fl mice, PKCβHep-/- mice showed elevated energy expenditure with augmentation of oxygen consumption and carbon dioxide production which was dependent on β3-adrenergic receptor signaling, thereby favoring negative energy balance. This effect was accompanied by induction of thermogenic genes in brown adipose tissue (BAT) and increased BAT respiratory capacity, as well as a shift to oxidative muscle fiber type with an improved mitochondrial function, thereby enhancing oxidative capacity of thermogenic tissues. Furthermore, in PKCβHep-/- mice, we determined that PKCβ overexpression in the liver mitigated elevated expression of thermogenic genes in BAT. In conclusion, our study thus establishes hepatocyte PKCβ induction as a critical component of pathophysiological energy metabolism by promoting progressive hepatic and extrahepatic metabolic derangements in energy homeostasis, contributing to late-onset obesity. These findings have potential implications for augmenting thermogenesis as a means of combating aging-induced obesity.

Total energy expenditure assessed by 24-h whole-room indirect calorimeter in patients with colorectal cancer: baseline findings from the PRIMe study

BACKGROUND

Total energy expenditure (TEE) determines energy requirements, but objective data in patients with cancer are limited.

OBJECTIVES

We aimed to characterize TEE, investigate its predictors, and compare TEE with cancer-specific predicted energy requirements.

METHODS

This cross-sectional analysis included patients with stages II-IV colorectal cancer from the Protein Recommendation to Increase Muscle (PRIMe) trial. TEE was assessed by 24-h stay in a whole-room indirect calorimeter before dietary intervention and compared with cancer-specific predicted energy requirements (25-30 kcal/kg). Generalized linear models, paired-samples t tests, and Pearson correlation were applied.

RESULTS

Thirty-one patients (56 ± 10 y; body mass index [BMI]: 27.9 ± 5.5 kg/m2; 68% male) were included. Absolute TEE was higher in males (mean difference: 391 kcal/d; 95% CI: 167, 616 kcal/d; P < 0.001), patients with colon cancer (mean difference: 279 kcal/d; 95% CI: 73, 485 kcal/d; P = 0.010), and patients with obesity (mean difference: 393 kcal/d; 95% CI: 182, 604 kcal/d; P < 0.001). Appendicular lean soft tissue (β: 46.72; 95% CI: 34.27, 59.17; P < 0.001) and tumor location (colon-β: 139.69; 95% CI: 19.44, 259.95; P = 0.023) independently predicted TEE when adjusted for sex. Error between measured TEE and energy requirements predicted by 25 kcal/kg (mean difference: 241 kcal/d; 95% CI: 76, 405 kcal/d; P = 0.010) or 30 kcal/kg (mean difference: 367 kcal/d; 95% CI: 163, 571 kcal/d; P < 0.001) was higher for patients with obesity, and proportional error was observed (25 kcal/kg: r = -0.587; P < 0.001; and 30 kcal/kg: r = -0.751; P < 0.001). TEE (mean difference: 25 kcal/kg; 95% CI: 24, 27 kcal/kg) was below predicted requirements using 30 kcal/kg (-430 ± 322 kcal/d; P < 0.001).

CONCLUSIONS

This is the largest study to assess TEE of patients with cancer using whole-room indirect calorimeter and highlights the need for improved assessment of energy requirements in this population. Energy requirements predicted using 30 kcal/kg overestimated TEE by 1.44 times in a controlled sedentary environment and TEE was outside of the predicted requirement range for most. Special considerations are warranted when determining TEE of patients with colorectal cancer, such as BMI, body composition, and tumor location. This is a baseline cross-sectional analysis from a clinical trial registered at clinicaltrials.gov as NCT02788955 (https://clinicaltrials.gov/ct2/show/NCT02788955).

Circulating Spexin Is Associated with Body Mass Index and Fat Mass but Not with Physical Activity and Psychological Parameters in Women across a Broad Body Weight Spectrum

Spexin (SPX) is a novel, widely expressed peptide, with anorexigenic effects demonstrated in animal models and negatively correlated with body mass index (BMI) in humans. It increases locomotor activity in rodents and is elevated in human plasma following exercise. Studies have also shown an effect of stress and anxiety on SPX’s expression in different brain structures in animals. The relationships between plasma SPX and physical activity, body composition, and patient-reported outcomes such as perceived stress, depressiveness, anxiety, and eating behaviors are unknown and were examined in this study over a wide BMI range. A total of 219 female (n = 68 with anorexia nervosa; n = 79 with obesity; n = 72 with normal weight) inpatients were enrolled. Perceived stress (PSQ 20), anxiety (GAD 7), depressiveness (PHQ 9), and eating disorder pathology (EDI 2), as well as BMI, bioimpedance analysis, and accelerometry, were measured cross-sectionally at the beginning of treatment and correlated with plasma SPX levels (measured by ELISA) obtained at the same time. Plasma SPX levels were negatively associated with BMI (r = −0.149, p = 0.027) and body fat mass (r = −0.149, p = 0.04), but did not correlate with perceived stress, anxiety, depressiveness, eating behavior, energy expenditure, and physical activity (p > 0.05). The results replicate the negative correlation of SPX with BMI and fat mass, but do not support the hypothesis that peripheral SPX plays a role in the regulation of stress, depressiveness, anxiety, eating behavior, or physical activity.

Effects of a 3-Week In-Hospital Multidisciplinary Body Weight Reduction Program in Obese Females: Is Measured Resting Energy Expenditure Essential for Tailoring Adequately the Amount of Energy Intake?

In the obese population, the prescription of a proper diet plan is essential to ensure an appropriate and gradual weight loss, reduce the risk of weight cycling and favor an overall improvement of health conditions. Energy needs are commonly estimated using predictive equations, even if their accuracy is still debated, especially in severely obese subjects. In the present study, 850 severely obese females admitted to our hospital for a multidisciplinary body weight reduction program (BWRP) were divided into three subgroups, “hypo-,” “normo-,” and “hyper-metabolic,” based on the comparison between estimated resting energy expenditure (eREE, using the Mifflin equation) and measured REE (mREE, using indirect calorimetry). The majority of this study population was considered normo-metabolic (59.4%, mREE between 90 and 110% of eREE), 32.6% was hyper-metabolic (mREE > 110% of eREE) and only 8% was hypo-metabolic (mREE < 90% of eREE). The three subgroups were evaluated before and after a 3-week BWRP, entailing energy restricted diet, adapted physical activity, psychological counseling and nutritional education. Since the diet plan during the BWRP consisted of a 30% reduction of total energy expenditure (obtained by multiplying mREE by the physical activity level), each subgroup responded positively to the BWRP independently from the difference between mREE and eREE, the extent of BMI reduction and clinical, metabolic and physical amelioration being comparable among the three subgroups. By contrast, the restriction of the energy intake based on eREE during the BWRP would have determined a slighter caloric restriction in the hypo-metabolic subgroup, thus determining a smaller body weight reduction, and, by contrast, a more marked caloric restriction in the hyper-metabolic subgroup, probably difficult to be tolerated and maintained for prolonged period. In conclusion, the percentage of subjects with “slow metabolism” in a Caucasian female obese population seeking hospitalization for a BWRP is actually lower than expected, finding controverting the common notion that obesity is mostly due to reduced REE. The high percentage (40%) of inadequate eREE in these female obese populations further underlines the absolute need to include the measurement of REE in the clinical practice for the correct prescription of energy intake in severely obese populations.

Validity of Accelerometers for the Evaluation of Energy Expenditure in Obese and Overweight Individuals: A Systematic Review

OBJECTIVE

Even though the validity of accelerometers for the measurement of energy expenditure (EE) has been demonstrated for normal-weight individuals, the applicability of this instrument in obese individuals remains controversial. This review aims to summarize the level of agreement between accelerometers and the gold standards (indirect calorimetry and doubly labelled water) for the measurement of energy expenditure (EE) in obese or overweight individuals.

METHODS

The literature search was limited to comparison studies assessing agreement in EE determination between accelerometers and indirect calorimetry (IC) or doubly labelled water (DLW). We searched in PubMed and in Scopus until March 1, 2019. The analysis was restricted to obese or overweight adult individuals. The following descriptive information was extracted for each study: sample size, characteristics of participants (sex, age, BMI, fat mass percentage, any pathological conditions, modality of recruitment in the study, and exclusion criteria), accelerometer description (model, type and body position), and type of gold standard and validity protocol (duration, conditions, and requirements during and before the experiment). Three review authors independently screened the obtained results, and the quality of the selected articles was assessed by the QUADAS-2 tool.

RESULTS

We obtained seventeen eligible articles, thirteen of which showed concerns for the applicability section, due to the patient selection. Regarding the accelerometers, nine devices were validated in the included studies with the BodyMedia SenseWear® (SWA) being the most frequently validated. Although correlations between accelerometers and the gold standard were high in some studies, agreement between the two methods was low, as shown by the Bland-Altman plots.

CONCLUSIONS

Most accelerometer estimations of EE were inaccurate for obese/overweight subjects, and authors advise to improve the accuracy of algorithms for SWA software, or the predicted equations for estimating EE from other accelerometers.

Declared and real physical activity in obese individuals as assessed by the questionnaire and accelerometer

BACKGROUND

Due to the lack of precise research data related to the evaluation of the physical activity level (PAL) among obese individuals, the aims of the study were to evaluate declared and real volume of physical activity, and to assess the correlations between these methods.

METHODS

The study consisted of 30 female (M<inf>age</inf>=32.9±7.3 years) and 16 male (M<inf>age</inf>=36.4±8.4 years) a total of 46 obese volunteer individuals were included (M<inf>bmi</inf>: 37.6±6.6 kg/m², M<inf>bmi</inf>: 34.2±4.3 kg/m²; body fat percentage: 42.1% and 35.2%, respectively). A cross-sectional study was conducted on the obese people. The information form was prepared for obese individuals who applied the Health Institutions and body composition measurements were performed with Tanita BC-1000. PAL was assessed objectively by a Sense Wear Armband (SWA) for 7 consecutive days- and seven day later the participants fill out the International Physical Activity Questionnaire - Short Form (IPAQ-SF). For statistical analysis, the data were presented as mean values, Standard deviations (SD), frequency (f), and percentage (%). Spearman's Rho Correlation were used, and the significant level was P<0.05.

RESULTS

According to IPAQ and SWA, 69.6% (10.9% plus 58.7%) of the participants (N.=32) estimated activity levels as "correct." The PAL of 30.4% (N.=14) of the participants does not seem to be consistent. According to the IPAQ and SWA, the rates of moderate-vigorous physical activity (MVPA) were 80.4%, 67.4% respectively. Weak correlation was found-between IPAQ-MET and SWA-step/day and SWA-MET respectively (r<inf>(</inf>s)=0.381; 0.410 (P<0.01).

CONCLUSIONS

Physical activity level being assessed by a subjective method was different from the objective method in obese individuals. In addition to this, sample groups and limitations should be taken into consideration when determining suitable methods.

A Retrospective Study about the Differences in Cardiometabolic Risk Indicators and Level of Physical Activity in Bariatric Surgery Patients from Private vs. Public Units

Background: Obesity is a pathology with a growing incidence in developing countries. Objective: To evaluate the evolution of cardiometabolic, anthropometrics, and physical activity parameters in individuals undergoing bariatric surgery (BS) in the public healthcare system (PUS) and private healthcare system (PHS). Methods: A longitudinal, observational, and retrospective study was conducted with 111 bariatric patients on two different health systems, with 60 patients from the PUS and 51 from the PHS. Cardiometabolic risk (CR) was analyzed by the assessment of obesity-related comorbidities (AORC) on admission and 3, 6, and 12 months after BS, and the International Physical Activity Questionnaire (IPAQ) was surveyed before and 12 months after BS. In addition, cardiometabolic risk was also assessed by biochemical (fasting glucose and complete lipidogram) and anthropometric (weight, weight loss, waist circumference, and waist-to-height ratio) parameters. Results: On admission, the parameters of severe obesity, systemic arterial hypertension (SAH), Diabetes mellitus (DM), and waiting time to BS were higher in the PUS. Additionally, in the PUS, AORC was reduced only in the SAH parameter. However, in the post-surgery moment, AORC reduced, and there was no difference between the two groups after BS. Regarding physical activity, the IPAQ showed a higher level of activity in the PHS before and one year after BS. Conclusion: At the PUS, BS is performed in patients with a higher degree of comorbidities, but BS improved the reduction of the CR at a similar level to those observed in the PHS.

Assessment of Cardiometabolic Risk Factors, Physical Activity Levels, and Quality of Life in Stratified Groups up to 10 Years after Bariatric Surgery

Obesity is a highly prevalent chronic metabolic disease, with an increasing incidence, and is currently approaching epidemic proportions in developing countries. Ouraim was to evaluate the activity levels, quality of life (QoL), clinical parameters, laboratory parameters, and cardiometabolic risk factors afterbariatric surgery (BS). We classified78 patients who underwentBS into four groups, as follows: Those evaluated 1-2 years after BS (BS2), 2-4 years after BS (BS4), 4-6 years after BS (BS6), and 6-10 years after BS (BS+6). Body weight (BW), body mass index (BMI), comorbidities associated with obesity (ACRO), physical activity level, and QoL were evaluated. Patients exhibited improvements in BW, BMI, cardiometabolic risk, hypertension, dyslipidemia, and diabetes and significant changes in lipid profiles in the first postoperative yearafter BS.The physical activity level inthe BS2, BS4, and BS6 groups was increased, compared with that in the first postoperative year, with a decrease in International Physical Activity Questionnaire scores at 1 year in the BS2 (207.50 ± 30.79), BS4 (210.67 ± 33.69), and BS6 (220.00 ± 42.78) groups. The QoL of patients in theBS2 and BS4 groups was excellent and that of patients in the BS4 and BS+6 groupswas very good. These findings suggest that BS promoted improved physical activity levels and QoL and reduced comorbidities in patients with morbid obesity.

The pathogenesis of obesity

Body fat mass increases when energy intake exceeds energy expenditure. In the long term, a positive energy balance will result in obesity. The worldwide prevalence of obesity has increased dramatically, posing a serious threat to human health. Therefore, insight in the pathogenesis of obesity is important to identify novel prevention and treatment strategies. This review describes the physiology of energy expenditure and energy intake in the context of body weight gain in humans. We focus on the components of energy expenditure and the regulation of energy intake. Finally, we describe rare monogenetic causes leading to an impairment in central regulation of food intake and obesity.

A "NEAT" Approach to Obesity Prevention in the Modern Work Environment

Increased prevalence of obesity may be due to an increase of being sedentary at work. Increasing non-exercise activity thermogenesis (NEAT) using walking workstations may increase total physical activity and promote a leaner physical body composition (or phenotype). The purpose of this study was to test whether walking slowly during work was sufficient to promote a leaner phenotype by increasing physical activity in sedentary desk workers without inducing compensation or a decrease in activity or energy expenditure during the nonworking hours. We conducted a prospective cohort study using a within-subjects crossover design. The design involved two phases each lasting 2 weeks: a treadmill exercise phase in which subjects used a walking workstation for 2.5 hours a day 5 days/week and a control phase in which subjects maintained their normal work activity. Twenty-five sedentary adults working at the Minneapolis VA Health Care System. We measured body weight, body composition, food intake, 24-hour physical activity, and self-reported physical activity with the International Physical Activity Questionnaire (IPAQ). Treadmill exercise caused a leaner phenotype (lean mass gain and fat mass loss) and significantly increased their 24-hour physical activity. Walking workstation use had favorable effects on physical well-being and mental focus and did not adversely affect productivity. Light treadmill exercise during work can increase physical activity and result in a leaner body composition. This is a potentially useful intervention to increase NEAT in the modern sedentary work environment.

Non-exercise activity thermogenesis (NEAT): a component of total daily energy expenditure

[Purpose]

The purpose of this review is to promote awareness of non-exercise activity thermogenesis (NEAT) as a new strategy to increase energy expenditure, and to manage obesity.

[Methods]

The content of this review is based on a literature search of PubMed and the Google Scholar search engine, using the search terms obesity, energy expenditure, non-exercise activity thermogenesis (NEAT), and sitting disease.

[Results]

Daily energy expenditure is of great interest because most obese individuals have no exercise activity-related thermogenesis (EAT); thus their physical activity-related energy expenditure (PEE) is comprised almost entirely of NEAT. Consequently, NEAT represents the main variable component of daily total energy expenditure (TEE); this varies considerably, both within among individuals. These somewhat unplanned and unstructured low level physical activities are associated with energy expenditure in excess of the resting metabolic rate (RMR). They may therefore have the potential to stimulate greater energy expenditure over time with a higher rate of adherence.

[Conclusion]

In conclusion, NEAT is a highly variable component of daily TEE and a low level of NEAT is associated with obesity. NEAT enhances lifestyle, and variations in individual and environmental factors can significantly affect daily energy expenditure. Therefore, well designed longitudinal studies that focus on personal behavioral approaches and re-engineered environments to increase NEAT should be conducted in the future.

Why Do Mice Overeat High-Fat Diets? How High-Fat Diet Alters the Regulation of Daily Caloric Intake in Mice

OBJECTIVE

Ad libitum high-fat diets (HFDs) spontaneously increase caloric intake in rodents, which correlates positively with weight gain. However, it remains unclear why rodents overeat HFDs. This paper investigated how changing the proportion of diet that came from HFDs might alter daily caloric intake in mice.

METHODS

Mice were given 25%, 50%, or 90% of their daily caloric need from an HFD, along with ad libitum access to a low-fat rodent chow diet. Food intake was measured daily to determine how these HFD supplements impacted total daily caloric intake. Follow-up experiments addressed the timing of HFD feeding.

RESULTS

HFD supplements did not alter total caloric intake or body weight. In a follow-up experiment, mice consumed approximately 50% of their daily caloric need from an HFD in 30 minutes during the light cycle, a time when mice do not normally consume food.

CONCLUSIONS

An HFD did not disrupt regulation of total daily caloric intake, even when up to 90% of total calories came from the HFD. However, HFDs increased daily caloric intake when provided ad libitum and were readily consumed by mice outside of their normal feeding cycle. Ad libitum HFDs appear to induce overconsumption beyond the mechanisms that regulate daily caloric intake.

Why intensity is not a bad word: Optimizing health status at any age

Age-related declines in health and function make locomotion increasingly difficult leading to reductions in non-exercise activity thermogenesis (NEAT), skeletal muscle size and strength, and increased adiposity. Exercise is an important strategy to attenuate loss of function through the life cycle. Despite claims to the contrary, high-intensity exercise is important for the prevention of obesity and sarcopenia with advancing age. Therefore, the purpose of this mini-review is to present literature supporting the contention that low volume, high-intensity aerobic and/or resistance training can slow sarcopenia, sustain ease of movement, stimulate NEAT, and attenuate the accretion of fat mass.

Leptin and Physical Activity in Adult Patients with Anorexia Nervosa: Failure to Demonstrate a Simple Linear Association

High physical activity (PA) in patients with anorexia nervosa (AN) is hypothesized to be, at least in part, a consequence of hypoleptinemia. However, most studies on the association of leptin and PA in AN were performed in adolescents or young adults, and PA was generally measured with subjective tools. We aimed to explore the association of leptin and PA in adults with AN using an objective technique to quantify PA. Using a cross-sectional, observational design, we analyzed body fat (bioelectrical impedance), PA (accelerometry, SenseWear™ armband) and plasma leptin (ELISA) in 61 women with AN (median age: 25 years, range: 18–52 years; median BMI: 14.8 ± 2.0 kg/m²) at the start of hospitalization. Results indicated a mean step count per day of 12,841 ± 6408 (range: 3956–37,750). Leptin was closely associated with BMI and body fat (ρ = 0.508 and ρ = 0.669, p < 0.001), but not with steps (ρ = 0.015, p = 0.908). Moreover, no significant association was observed between BMI and steps (ρ = 0.189, p = 0.146). In conclusion, there was no simple, linear association of leptin and PA, highlighting the need for more complex and non-linear models to analyze the association of leptin and PA in adults with AN in future studies.

Validity and reliability of an adapted arabic version of the long international physical activity questionnaire

Background

The International Physical Actvity Questionnaire (IPAQ) is a validated tool for physical activity assessment used in many countries however no Arabic version of the long-form of this questionnaire exists to this date. Hence, the aim of this study was to cross-culturally adapt and validate an Arabic version of the long International Physical Activity Questionnaire (AIPAQ) equivalent to the French version (F-IPAQ) in a Lebanese population.

Methods

The guidelines for cross-cultural adaptation provided by the World Health Organization and the International Physical Activity Questionnaire committee were followed. One hundred fifty-nine students and staff members from Saint Joseph University of Beirut were randomly recruited to participate in the study. Items of the A-IPAQ were compared to those from the F-IPAQ for concurrent validity using Spearman’s correlation coefficient. Content validity of the questionnaire was assessed using factor analysis for the A-IPAQ’s items. The physical activity indicators derived from the A-IPAQ were compared with the body mass index (BMI) of the participants for construct validity. The instrument was also evaluated for internal consistency reliability using Cronbach’s alpha and Intraclass Correlation Coefficient (ICC). Finally, thirty-one participants were asked to complete the A-IPAQ on two occasions three weeks apart to examine its test–retest reliability. Bland-Altman analyses were performed to evaluate the extent of agreement between the two versions of the questionnaire and its repeated administrations.

Results

A high correlation was observed between answers of the F-IPAQ and those of the A-IPAQ, with Spearman’s correlation coefficients ranging from 0.91 to 1.00 (p < 0.05). Bland-Altman analysis showed a high level of agreement between the two versions with all values scattered around the mean for total physical activity (mean difference = 5.3 min/week, 95% limits of agreement = −145.2 to 155.8). Negative correlations were observed between MET values and BMI, independent of age, gender or university campus. The A-IPAQ showed a high internal consistency reliability with Cronbach’s alpha ranging from 0.769–1.00 (p < 0.001) and intraclass correlation coefficient (ICC) ranging from 0.625–0.999 (p < 0.001), except for a moderate agreement with the moderate garden/yard activity (alpha = 0.682; ICC = 0.518; p < 0.001). The A-IPAQ had moderate-to-good test-retest reliability for most of its items (ICC ranging from 0.66–0.96; p < 0.001) and the Bland-Altman analysis showed a satisfactory agreement between the two administrations of the A-IPAQ for total physical activity (mean difference = 99.8 min/week, 95% limits of agreement = −1105.3; 1304.9) and total vigorous and moderate physical activity (mean difference = −29.7 min/week, 95% limits of agreement = −777.6; 718.2).

Conclusion

The modified Arabic version of the IPAQ showed acceptable validity and reliability for the assessment of physical activity among Lebanese adults. More studies are necessary in the future to assess its validity compared to a gold-standard criterion measure.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-017-4599-7) contains supplementary material, which is available to authorized users.

Is Obesity Associated with Altered Energy Expenditure?

Historically, obese individuals were believed to have lower energy expenditure (EE) rates than nonobese individuals (normal and overweight), which, in the long term, would contribute to a positive energy balance and subsequent weight gain. The aim of this review was to critically appraise studies that compared measures of EE and its components, resting EE (REE), activity EE (AEE), and diet-induced thermogenesis (DIT), in obese and nonobese adults to elucidate whether obesity is associated with altered EE. Contrary to popular belief, research has shown that obese individuals have higher absolute REE and total EE. When body composition (namely the metabolically active component, fat-free mass) is taken into account, these differences between obese and nonobese individuals disappear, suggesting that EE in obese individuals is not altered. However, an important question is whether AEE is lower in obese individuals because of a decrease in overall physical activity or because of less energy expended while performing physical activity. AEE and DIT could be reduced in obese individuals, mostly because of unhealthy behavior (low physical activity, higher intake of fat). However, the current evidence does not support the hypothesis that obesity is sustained by lower daily EE or REE. Future studies, comparing EE between obese and nonobese and assessing potential physiologic abnormalities in obese individuals, should be able to better answer the question of whether these individuals have altered energy metabolism.

Self-Directed Weight Loss Strategies: Energy Expenditure Due to Physical Activity Is Not Increased to Achieve Intended Weight Loss

Reduced physical activity and almost unlimited availability of food are major contributors to the development of obesity. With the decline of strenuous work, energy expenditure due to spontaneous physical activity has attracted increasing attention. Our aim was to assess changes in energy expenditure, physical activity patterns and nutritional habits in obese subjects aiming at self-directed weight loss.

METHODS

Energy expenditure and physical activity patterns were measured with a portable armband device. Nutritional habits were assessed with a food frequency questionnaire.

RESULTS

Data on weight development, energy expenditure, physical activity patterns and nutritional habits were obtained for 105 patients over a six-month period from an initial cohort of 160 outpatients aiming at weight loss. Mean weight loss was -1.5 ± 7.0 kg (p = 0.028). Patients with weight maintenance (n = 75), with substantial weight loss (>5% body weight, n = 20) and with substantial weight gain (>5% body weight, n = 10) did not differ in regard to changes of body weight adjusted energy expenditure components (total energy expenditure: -0.2 kcal/kg/day; non-exercise activity thermogenesis: -0.3 kcal/kg/day; exercise-related activity thermogenesis (EAT): -0.2 kcal/kg/day) or patterns of physical activity (duration of EAT: -2 min/day; steps/day: -156; metabolic equivalent unchanged) measured objectively with a portable armband device. Self-reported consumption frequency of unfavorable food decreased significantly (p = 0.019) over the six-month period.

CONCLUSIONS

An increase in energy expenditure or changes of physical activity patterns (objectively assessed with a portable armband device) are not employed by obese subjects to achieve self-directed weight loss. However, modified nutritional habits could be detected with the use of a food frequency questionnaire.

Associations of physical activity with depressiveness and coping in subjects with high-grade obesity aiming at bariatric surgery: a cross-sectional study

Background

Reduced physical activity is supposed to be associated with depressiveness and more passive coping patterns. For further evaluation of this assumed relation we studied energy expenditure due to physical activity - usually referred to as activity thermogenesis (AT) - together with depressiveness (clinical diagnosis, depression module of the Patient Health Questionnaire), and coping behaviours (Brief COPE Inventory) in 50 patients with high-grade obesity (42 ± 12 years; 9 with II° and 41 with III° obesity) aiming at bariatric surgery.

Methods

AT was assessed with a portable armband device (SenseWear™ armband). Depressiveness and coping were assessed using validated questionnaires.

Results

Weight-adjusted non-exercise AT and intensity of physical activity (metabolic equivalent) correlated inversely with body mass index (non-exercise AT: r = −0.32, P < 0.05; mean metabolic equivalent: r = −0.37, P < 0.01) but not with depressiveness. The coping strategies “support coping” and “active coping” showed significant inverse correlations to a) weight-adjusted non-exercise AT (“support coping”: r = −0.34, P < 0.05; “active coping”: r = −0.36, P < 0.05), b) weight-adjusted exercise-related AT (“support coping”: r = −0.36, P < 0.05; “active coping”: r = −0.38, P < 0.01) and c) intensity of physical activity (for mean metabolic equivalent: “support coping”: r = −0.38, P < 0.01; “active coping”: r = −0.40, P < 0.01; for duration of exercise-related AT: “support coping”: r = −0.36, P < 0.05; “active coping”: r = −0.38, P < 0.01).

Conclusions

AT was not associated with depressiveness. Furthermore, supposed adaptive coping strategies of individuals aiming at bariatric surgery were negatively associated with AT.

Plasma bile acids show a positive correlation with body mass index and are negatively associated with cognitive restraint of eating in obese patients

Bile acids may be involved in the regulation of food intake and energy metabolism. The aim of the study was to investigate the association of plasma bile acids with body mass index (BMI) and the possible involvement of circulating bile acids in the modulation of physical activity and eating behavior. Blood was obtained in a group of hospitalized patients with normal weight (BMI 18.5–25 kg/m²), underweight (anorexia nervosa, BMI < 17.5 kg/m²) and overweight (obesity with BMI 30–40, 40–50 and >50 kg/m², n = 14–15/group) and plasma bile acid concentrations assessed. Physical activity and plasma bile acids were measured in a group of patients with anorexia nervosa (BMI 14.6 ± 0.3 kg/m², n = 43). Lastly, in a population of obese patients (BMI 48.5 ± 0.9 kg/m², n = 85), psychometric parameters related to disordered eating and plasma bile acids were assessed. Plasma bile acids showed a positive correlation with BMI (r = 0.26, p = 0.03) in the population of patients with broad range of BMI (9–85 kg/m², n = 74). No associations were observed between plasma bile acids and different parameters of physical activity in anorexic patients (p > 0.05). Plasma bile acids were negatively correlated with cognitive restraint of eating (r = −0.30, p = 0.008), while no associations were observed with other psychometric eating behavior-related parameters (p > 0.05) in obese patients. In conclusion, these data may point toward a role of bile acids in the regulation of body weight. Since plasma bile acids are negatively correlated with the cognitive restraint of eating in obese patients, this may represent a compensatory adaptation to prevent further overeating.

Facilitators and barriers to using treadmill workstations under real working conditions: a qualitative study in female office workers

PURPOSE

Characterize barriers and facilitators to use treadmill workstations in real work sites.

DESIGN

For 6 months, workers tried a sit-stand-walk treadmill workstation at will with expert ergonomic support. Qualitative data were collected monthly.

SETTING

Administrative and academic departments at a higher education institution in Massachusetts, United States.

PARTICIPANTS

Five female administrative office workers.

METHOD

One monthly group interview and one personal interview per participant during 6 months. Emerging topics from previous interviews were used in successive data gatherings. Transcribed data were manually coded according to the predefined topics of usability, comfort, safety, and productivity.

RESULTS

The setup of the work station, communication difficulties while walking (disrespectful, noisy), and peer pressure to maximize use were the main usability barriers. There was no event of falls. Trips were minimized. About comfort, subjects reported it hard to get used to prolonged standing position during the first month. Treadmill speed affected productivity mostly while drawing and working in spreadsheets. Lack of job autonomy was revealed as a generic barrier.

CONCLUSION

In this female group, treadmill workstations had serious design problems for workers with not enough control of their jobs. The early identification and removal of barriers likely needs to be considered when offering these workstations to workers with low job autonomy.

Physical activity after surgically obtained weight loss: study with a SenseWear armband in subjects undergoing biliopancreatic diversion

BACKGROUND

This study aimed to understand the role of the extra load of body mass in limiting physical activity and in preventing an active lifestyle in severely obese patients.

MATERIALS AND METHODS

The study was carried out in a University Hospital setting, and investigates severely obese patients, having undergone biliopancreatic diversion (BPD) for obesity and control subjects with a body weight closely similar to that of the BPD subjects; energy intake was evaluated by alimentary interview and energy expenditure was assessed with the Body Media SenseWear® Pro armband (SWA).

RESULTS

SWA metabolic efficiency (MET) was negatively associated with body mass index values (ρ = -0.464, p < 0.01), and the SWA overall energy expenditure was very similar to the energy alimentary intake in the obese patients and in the control subjects. Among the controls, the MET mean value was higher (p < 0.05) than that observed both in obese and in BPD subjects (1.392 ± 0.211 vs. 1.149 ± 0.181 and 1.252 ± 0.284, respectively); furthermore, in comparison with the obese and the BPD groups, among the control individuals a greater number of active persons (27% vs. 0 and 7%, respectively) and a lower number of sedentary persons (27% vs. 70 and 43%, respectively) was found (p < 0.01).

CONCLUSIONS

These preliminary results suggest the reliability of SWA data in assessing energy expenditure and tend to rule out the hypothesis that in severely obese patients the extra load of body mass by itself is a main factor limiting physical activity and leading to a sedentary lifestyle.

Irisin Levels are Not Affected by Physical Activity in Patients with Anorexia Nervosa

Irisin was recently identified as muscle-derived hormone that increases energy expenditure. Studies in normal weight and obese subjects reported an increased irisin expression following physical activity, although inconsistent results were observed. Increased physical activity in a subgroup of patients with anorexia nervosa (AN) complicates the course of the disease. Since irisin could account for differences in clinical outcomes, we investigated irisin levels in anorexic patients with high and moderate physical activity to evaluate whether irisin differs with increasing physical activity. Hospitalized female anorexic patients (n = 39) were included. Plasma irisin measured by enzyme-linked immunosorbent assay and locomotor activity were assessed at the same time. Patients were separated into two groups (n = 19/group; median excluded): moderate and high activity (6331 ± 423 vs. 13743 ± 1047 steps/day, p < 0.001). The groups did not differ in body mass index (14.2 ± 0.4 vs. 15.0 ± 0.4 kg/m(2)), irisin levels (558.2 ± 26.1 vs. 524.9 ± 25.2 ng/ml), and body weight-adjusted resting energy expenditure (17.6 ± 0.3 vs. 18.0 ± 0.3 kcal/kg/day, p > 0.05), whereas body weight-adjusted total energy expenditure (46.0 ± 1.4 vs. 41.1 ± 1.1 kcal/kg/day), metabolic equivalents (METs, 1.9 ± 0.1 vs. 1.7 ± 0.1 METs/day), body weight-adjusted exercise activity thermogenesis (1.8 ± 0.5 vs. 0.6 ± 0.3 kcal/kg/day), duration of exercise (18.6 ± 4.7 vs. 6.2 ± 3.1 min/day), and body weight-adjusted non-exercise activity thermogenesis (21.6 ± 1.0 vs. 18.8 ± 0.8 kcal/kg/day) were higher in the high activity compared to the moderate activity group (p < 0.05). No correlations were observed between irisin and activity parameters in the whole sample (p > 0.05). In conclusion, the current data do not support the concept of irisin being induced by exercise, at least not under conditions of severely reduced body weight like AN.

Tailored behavioral medicine intervention for enhanced physical activity and healthy eating in patients with obstructive sleep apnea syndrome and overweight

PURPOSE

This study aims to evaluate the effects on physical activity (PA) and eating behavior (EB) of a tailored behavioral medicine intervention and first-time continuous positive airway pressure (CPAP) treatment compared with first-time CPAP treatment and advice in patients with obstructive sleep apnea syndrome (OSAS) and overweight.

METHODS

Seventy-three patients (mean ± SD, 55 ± 12 years) with overweight (body mass index (BMI), 34.5 ± 4.8) and moderate or severe OSAS (Apnea-Hypopnea Index, 41.7 ± 20.9) scheduled for CPAP prescription were randomized to a control group (CPAP and advice on the association between weight and OSAS) or an experimental group (CPAP and a 6-month behavioral medicine intervention targeting PA and EB). At baseline and after 6 months, eating behavior (food frequency screening and Dutch Eating Behavior Questionnaire), weight, BMI, and waist circumference were assessed at one point, while PA and sedentary time were measured with accelerometry during 4 days.

RESULTS

The experimental group reduced 2.1 kg (±4.6) in weight and 3 cm (±4.9) in waist circumference, significantly more than the control group. At 6 months, the experimental group ate more fruit and fish/shellfish than the control group. Low and moderate to vigorous PA did not change over time either within or between groups. Regarding BMI, steps, and sedentary time, there were within-group differences but no differences between groups.

CONCLUSIONS

The behavioral medicine intervention did not change physical activity but facilitated changes in EB in patients with OSAS and overweight. The amount of weight loss and reduction in waist circumference favored the participants receiving this treatment. Since the strategies for achieving behavioral changes were tailored according to the individual's goals and personal functional behavioral analyses and progressed slowly in a graded manner, it might require higher PA quotas or a period longer than 6 months to reveal a behavioral change of larger proportions.

Irisin: what promise does it hold?

PURPOSE OF REVIEW

The recently identified myokine, irisin has raised great expectations as a potential target in the conservative treatment of obesity. This review focuses on studies exploring the effects of irisin in humans.

RECENT FINDINGS

Peroxisome proliferator-activated receptor γ coactivator-1 α expression in skeletal muscles is induced by exercise followed by expression of the membrane protein fibronectin type III domain containing 5. After cleavage from fibronectin type III domain containing 5, irisin is secreted into blood increasing thermogenesis by browning of subcutaneous white/beige adipose tissue. Although clear-cut data have been reported in rodents, the thermogenic effect of irisin in humans remains controversial. The initially reported exercise-dependent increase of irisin in humans could not be confirmed in most studies. However, a robust finding in human studies is the association of irisin with BMI.

SUMMARY

The discovery of irisin provides more insight into exercise-induced browning of adipose tissue, and therefore leads to a better understanding of mechanisms underlying body weight regulation and further down the road possibly may lead to treatment strategies of diseases with greatly altered body weight such as obesity or anorexia nervosa.

Physical activity and sedentary time in persons with obstructive sleep apnea and overweight enrolled in a randomized controlled trial for enhanced physical activity and healthy eating

BACKGROUND

The aim of the study was to describe the amount of physical activity and sedentary time in patients with obstructive sleep apnea syndrome (OSAS) and overweight and to explore potential disease-related and psychological correlates.

METHODS

A descriptive and correlational study was performed. Prospective data of physical activity and sedentary time were collected through accelerometry, and body mass index (BMI), daytime sleepiness, exercise self-efficacy, fear of movement, and depressive symptoms were measured at one point. Seventy-three participants with overweight (mean BMI, 35 kg/m(2) (5 SD)) and moderate/severe OSAS (apnea-hypopnea index ≥15) were consecutively recruited. Multivariate associations were determined through multiple linear regression analysis.

RESULTS

The participants took a daily average of 7,734 (3,528 SD) steps, spent an average of 77 min (54 SD) in moderate-to-vigorous physical activity (MVPA), and spent 11 h and 45 min (2 h and 8 min SD) sedentary. BMI, daytime sleepiness, exercise self-efficacy, fear of movement, and depressive symptoms did not explain variance in MVPA or steps but explained 22.9 % of variance in sedentary time. In backward selection analysis, BMI contributed to the explanatory degree of MVPA with 9 % whereas, fear of movement explained 6.3 % of the variance in steps and 14.3 % of the variance in sedentary time.

CONCLUSIONS

An important implication for future physical activity interventions is that both physical activity and sedentary behaviors should be targeted, and fear of movement may be an important determinant for change in patients with OSAS and overweight.

Estimating resting energy expenditure with a portable armband device in an ambulatory setting

BACKGROUND

The measurement of resting energy expenditure (REE) in an ambulatory setting raises methodological problems. Therefore, the use of predictive equations for the estimation of REE is common. Alternatively, the measurement of sleeping energy expenditure (SEE) has been proposed. The authors retrospectively analyzed data on SEE assessed with a portable armband (PA) device in an ambulatory setting and evaluated this approach against predictive equations and REE measured by indirect calorimetry (IC).

METHODS

REE was measured with IC, and SEE was assessed with the PA using standardized conditions in 81 participants (aged 46 ± 13 years) over a wide range of body weight (mean body mass index [BMI] 36.4 ± 9.3 kg/m(2); range, 21.6-55.7).

RESULTS

SEE (1756 ± 393 kcal/d) was 7.6% higher than REE (1632 ± 346 kcal/d) (P < .001). This difference (123 ± 214 kcal/d) was smaller than that using the predictive equation for REE by Harris and Benedict (207 ± 217 kcal/d) and the BMI group-specific equations according to Müller et al (209 ± 190 kcal/d). Linear regression analysis was significant (r (2) = 0.705; P < .001). SEE showed similar 95% confidence intervals compared with both of the predictive equations.

CONCLUSIONS

The described standardized assessment of SEE by a PA device appears to be a promising approach to estimate REE in an ambulatory setting. SEE reflects REE at least as precisely as the predictive equations.

Physical activity and cardiovascular risk factors in Spanish children aged 11-13 years

INTRODUCTION AND OBJECTIVES

The prevalence of childhood obesity has increased in recent decades. The aim was to determine whether a 3-month intervention on daily physical activity at school could affect body weight and cardiovascular risk factors associated with childhood obesity.

METHODS

A total of 137 children (12[1] years old) volunteered to participate in an observational cross-sectional study. Children were allowed to join one of the following groups: a) sedentary group (2h/week of physical education at school); b) active group (2h/week of physical education at school plus 3h/week extra physical activity), and c) sports group (2h/week of physical education at school plus 5h/week extra physical activity). Anthropometric characteristics, blood pressure, physical condition (estimated by the Course-Navette test), and biochemical parameters related with cardiovascular risk factors were determined.

RESULTS

Body weight, body mass index, waist circumference, sum of skinfold thickness, body fat percentage, and fat mass index of children were decreased with high physical activity level, whereas body water content significantly increased with activity. Parameters related with cardiovascular risk -triglycerides, insulin, systolic blood pressure, and homeostatic model assessment index- presented lower values in the sports group. Maximal oxygen uptake and maximum heart rate (Course Navette test) progressively increased with activity. Children participating in a total of 7h/week of physical activity presented significantly lower odds ratio of having high levels of the following cardiovascular risk factors: waist circumference, fat mass index, and homeostatic model assessment index.

CONCLUSIONS

Physical activity is important for metabolic health in children. Children with higher levels of physical activity presented better anthropometric and biochemical profiles.

Patterns of physical activity and sedentary behavior in normal-weight, overweight and obese adults, as measured with a portable armband device and an electronic diary

BACKGROUND & AIMS

Accurate data on domain-specific physical activity and sedentary behavior among normal-weight, overweight and obese adults are scarce. This study described a comprehensive physical (in)activity profile and examined variations in activity across the week.

METHODS

Physical activity was measured in 442 Flemish adults (41.4 ± 9.8 years) for 7 days using the SenseWear Armband and an electronic diary. Differences in (in)activity between BMI subgroups were examined using one-way analyses of variance.

RESULTS

Physical activity level decreased with increasing BMI in men (1.77-1.46 MET) and women (1.67-1.31 MET). Sedentary time was higher in obese than normal-weight men (+1.09 h/day) and overweight and obese than normal-weight women (+1.04 and +1.88 h/day). Total hours of moderate-to-vigorous activity and bouts of moderate-to-vigorous activity were lower in overweight and obese than normal-weight subjects. The average duration of a sedentary bout and the number of breaks in sedentary time were only different between female BMI groups. The intensity of domain-specific activities decreased with increasing BMI. Activity patterns across the week differed between subgroups, with the difference most pronounced on Saturday for the male BMI groups.

CONCLUSIONS

This study described activity patterns among normal-weight, overweight and obese adults. The results should be used to design obesity prevention strategies.