Assessment of body composition in pediatric overweight and obesity: A systematic review of the reliability and validity of common techniques

Ethnicity modifies the relationship between added sugars and fructose exposure in the first 1000 days and offspring body composition at 24 months

Added sugars (AS) and fructose intake are linked to obesity. Hispanic populations experience high AS intake and obesity rates. It is underexplored if early sugars exposure influences offspring growth, especially across ethnic groups. This secondary analysis examined if AS and fructose intake during pregnancy, infancy, and toddlerhood influenced offspring adiposity at 24 months, and if ethnicity modified outcomes. We hypothesized that higher sugars exposure would predict increased adiposity. Mother-child pairs from a prenatal docosahexaenoic acid supplementation RCT and the offspring follow-up study were included. Dietary intake was assessed at 12 to 20 weeks gestation, and offspring intake at 2 weeks, 6 months, 12 months, and 24 months. Intake was averaged across infancy (Year 1: 2 weeks/6 months) and toddlerhood (Year 2: 12 months/24 months). Anthropometric (n = 130) and dual-energy X-ray absorptiometry (n = 42) data were collected at 24 months. Multiple hierarchical regression examined associations, with interaction terms testing ethnic differences. Higher AS intake in Year 1 predicted higher weight, fat-free mass, and total adiposity. Compared to non-Hispanic offspring, the association of Year 1 fructose intake with weight and Year 2 AS intake with fat-free mass and central fat mass, were weaker in Hispanic offspring. No other significant associations were observed. The relationships between early AS and fructose intake with body composition are dynamic over time and vary by ethnicity. Our findings highlight the potential risks of early sugars exposure on obesity and metabolic health, underscoring the need for further research to inform early-life dietary interventions and public health policies.

Comparing digital anthropometrics from mobile applications to reference methods: a scoping review

This scoping review aimed to assess the repeatability and accuracy of Digital Anthropometry by Mobile Application (DAM) compared to reference methods for estimating anthropometric dimensions, body volume (BV), and body composition. A comprehensive search was conducted on December 8th, 2024, without restrictions on language, time, sex, ethnicity, age, or health condition. We found 14 different DAMs across the 23 included studies. Reference methods for each estimated variable were: (a) Body circumferences-tape measure; (b) body mass-calibrated scale; (c) body length-stadiometer; (d) BV-Underwater Weighing; (e) percentage of body fat-Dual energy x-ray absorptiometry (DXA), BOD POD, 3, 4, and 5-compartment models; (f) fat mass and fat-free mass-DXA, 3 and 4-compartment models; (g) appendicular Lean Mass-DXA. DAMs demonstrated high repeatability and accuracy at a mean level in most studies. However, their accuracy is lower at individual-level analysis and for tracking changes over time. Estimated BV showed high accuracy compared to UWW (SEE = 0.68; MD = 0.04 to 0.1; LoA = 2.86), including the BV-derived DAMs integrated into alternative multi-compartment models compared to reference methods. As relatively new methods, DAMs offer numerous possibilities and areas for exploration in future studies. However, caution is advised due to their potentially low or unknown accuracy at the individual level.

Childhood obesity: The threatening apprentice of the adiposity empire

Childhood obesity is a global health problem, with its prevalence having tripled since 1975. The increase in its prevalence has been predominantly in developing countries, but also in those with high economic status. Nowadays, there are multiple obesity definitions, however, one of the most accurate is the one which defines obesity as the accumulation of excessive body adiposity and not as an body weight excess. Nevertheless, the body mass index (BMI) is the most frequently used tool for its classification, according to the cut-off points established by the Center for Disease Control and World Health Organization tables. In children and adolescents an adiposity excess is related to the appearance of cardiovascular disease in adulthood and with many comorbidities such as metabolic syndrome, insulin resistance, type 2 diabetes, hypertension and metabolic dysfunction-associated steatotic liver disease, among others. Currently, there is still controversy about which is the ideal indicator for measuring overweight and obesity. BMI is still used as a standardized measure but may miss cases in which body composition is pathological despite a BMI within the normal-weight category. An adequate knowledge of the impact on health of dysfunctional adiposity as well as its accurate diagnosis will allow health professionals to address this condition in a more precise and comprehensive manner, and substantially improve the associated cardiometabolic risk and prognosis.

The Chinese version of the physical activity questionnaire for adolescents: a psychometric validity, reliability, and invariance study

BACKGROUND

The Physical Activity Questionnaire for Adolescents (PAQ-A) is one of the most commonly used questionnaires for assessing adolescents' levels of moderate to vigorous physical activity (PA). Although a Chinese version of the PAQ-A (comprising nine items) exists, it has been assessed for only internal consistency coefficients, test-retest reliability, and correlations with the GT3X + accelerometer. Therefore, this study aimed to evaluate the psychometric properties of the Chinese version of the PAQ-A among Chinese adolescents.

METHODS

This study included three samples of 1,101 secondary school students (12-19 years old). The first sample consisted of 518 participants (50.4% males, 49.6% females) for correlation tests and exploratory factor analysis (EFA). The second sample consisted of 227 participants (55.75% males, 44.24% females) for confirmatory factor analysis (CFA), convergent validity, and sample size invariance tests. The third sample consisted of 356 participants (54.50% male, 45.50% female) for the internal consistency reliability test, invariance test (cross sample size, education level and gender), and t-test.

RESULTS

Pearson correlation analysis of the PAQ-A indicated that all the total-item correlations exceeded 0.2, indicating good consistency across the items. Subsequent EFA of the Chinese version of the PAQ-A revealed a two-factor structure. CFA subsequently validated this structure. One of the items exhibited a standardized loading below 0.4 and was excluded. The exclusion of this item resulted in increased standardized loadings for the remaining items, ranging from 0.40 to 0.82, which indicates improved fit indices. This adjustment underscores the questionnaire's satisfactory convergent validity and robust discriminant validity. The overall Cronbach's alpha was 0.821, with the values for the first and second factors being 0.757 and 0.716, respectively. The questionnaire demonstrated stable invariance across sample sizes and education levels and additionally showed partial scalar invariance across genders. A t-test revealed a significant difference between males and females, which aligns with previous findings. These findings supported the construct validity of the questionnaire.

CONCLUSION

This study validated the Chinese version of the PAQ-A for assessing adolescent PA in China, with a two-factor structure improved by removing one item.

Body composition from birth to 2 years

Providing all infants with the best start to life is a universal but challenging goal for the global community. Historically, the size and shape of infants, quantified by anthropometry and commencing with birthweight, has been the common yardstick for physical growth and development. Anthropometry has long been considered a proxy for nutritional status during infancy when, under ideal circumstances, changes in size and shape are most rapid. Developed from data collected in the Multicentre Growth Reference Study (MGRS), WHO Child Growth Standards for healthy infants and children have been widely accepted and progressively adopted. In contrast, and somewhat surprisingly, much less is understood about the 'quality' of growth as reflected by body composition during infancy. Recent advances in body composition assessment, including the more widespread use of air displacement plethysmography (ADP) across the first months of life, have contributed to a progressive increase in our knowledge and understanding of growth and development. Along with stable isotope approaches, most commonly the deuterium dilution (DD) technique, the criterion measure of total body water (TBW), our ability to quantify lean and fat tissue using a two-compartment model, has been greatly enhanced. However, until now, global reference charts for the body composition of healthy infants have been lacking. This paper details some of the historical challenges associated with the assessment of body composition across the first two years of life, and references the logical next steps in growth assessments, including reference charts.

Maternal weight status at conception predicts offspring body fat at age 11 years: population data from the Japan Kids Body Composition Study using dual-energy X-ray absorptiometry

BACKGROUND

Maternal preconception overweight status has been reported to be associated with an increased risk of overweight offspring. However, there are no published population-based studies on the association between maternal preconception weight and offspring body fat measured by dual-energy X-ray absorptiometry (DXA). The present population-based retrospective cohort study aimed to examine the association between maternal weight at conception and offspring body fat measured by DXA.

METHODS

The source population consisted of 5th-grade students (1244 students aged 11 years) registered at 8 municipal elementary schools in Kitakata, Fukuroi, Hamamatsu, and Himeji in Japan. The present analyses included 964 participants who provided complete information. Maternal body mass index (BMI) at conception was calculated using records in the Mother and Child Health Handbook (MCHH). Offspring body fat at age 11 years was measured with the same QDR-4500A DXA instrument in a mobile test room that was brought to each school. With regard to the prediction of excess fat in offspring, the area under the curve (AUC) calculated with receiver operating characteristic curve analysis was used to quantify the diagnostic accuracy of maternal BMI at conception.

RESULTS

Adjusted odds ratios for excess body fat in offspring of the overweight mother group (odds ratios, 4.93 to 15.32) were significantly higher than those in the non-overweight mother group. For the prediction of excess offspring fat, AUCs and 95% confidence intervals for maternal BMI at conception were greater than 0.5.

CONCLUSION

Maternal overweight status at conception might be a risk factor for excess body fat in offspring. Maternal BMI values calculated using MCHH data have the potential to distinguish between the presence and absence of excess fat in the next generation.

Sex- and gender-based medicine in pediatric nutrition

Consistent evidence increasingly highlights the significance of integrating sex and gender medicine to ensure a precision approach according to individual patient needs. Gender discrepancies emerge across various areas, even from pediatric age. The importance of recognizing these differences in pediatric nutrition is critical for the development of targeted nutritional strategies and interventions, particularly in cases of associated pathologies, including obesity, metabolic-associated fatty liver disease, eating disorders, and inflammatory bowel disease. The review highlights the biological and sociocultural factors that contribute to different nutritional needs and health outcomes in male and female children. By examining current evidence, we underscore the necessity for precision medicine approaches in pediatric care that consider these sex- and gender-based differences. Moreover, differences in dietary requirements and dietary patterns between males and females are evident, underscoring the need for precise nutrition strategies for a more accurate management of children and adolescents. This approach is essential for improving clinical outcomes and promoting equitable healthcare practices. This review aims to provide an overview of nutrition-related medical conditions exhibiting sex- and gender-specific discrepancies, which might lead to distinct outcomes requiring unique management and prevention strategies. Future research and public health initiatives should address these differences in designing effective lifestyle education programs and nutrition interventions targeting both children and adolescents.

The metabolic load-capacity model and cardiometabolic health in children and youth with obesity

BACKGROUND

The metabolic load-capacity index (LCI), which represents the ratio of adipose to skeletal muscle tissue-containing compartments, is potentially associated with cardiometabolic diseases.

OBJECTIVES

To examine the associations between the LCI and cardiometabolic risk factors in children and youth with obesity.

METHODS

This is a cross-sectional study including 10-18 years-old participants with a BMI of ≥95th . LCI by air-displacement plethysmography (ADP) was calculated as fat mass divided by fat-free mass, and LCI by ultrasound (US) as subcutaneous adipose tissue divided by skeletal muscle thickness. Sex-specific medians stratified participants into high versus low LCI. Single (inflammation, insulin resistance, dyslipidemia and hypertension) and clustered cardiometabolic risk factors were evaluated. Linear and logistic regression models tested the associations between these variables, adjusted for sexual maturation.

RESULTS

Thirty-nine participants (43.6% males; 59% mid-late puberty) aged 12.5 (IQR: 11.1-13.5) years were included. LCI by ADP was positively associated with markers of inflammation and dyslipidemia; having a higher LCI predicted dyslipidemia in logistic regression. Similarly, LCI by US was positively associated with markers of dyslipidemia and blood pressure. In mid-late pubertal participants, LCI by US was positively associated with markers of insulin resistance and inflammation.

CONCLUSIONS

Participants with unfavourable cardiometabolic profile had higher LCI, suggesting its potential use for predicting and monitoring cardiometabolic health in clinical settings.

Body mass index is not suitable for assessing body composition in children with spastic cerebral palsy

PURPOSE

To measure body composition by using bioelectrical impedance analysis (BIA) and body mass index (BMI) and to investigate the correlation and agreement between BMI and fat mass percentage in children with spastic Cerebral Palsy.

MATERIALS AND METHODS

BIA was used to assess fat mass percentage and BMI was determined from body weight and height. BMI and fat mass percentage were both categorized into five categories. The association between fat mass percentage and BMI was assessed using Pearson's correlation coefficient. Agreement between BMI and fat mass percentage was investigated with weighted Cohen's kappa coefficient.

RESULTS

One hundred and three children with CP across all Gross Motor Function Classification Levels (61% boys, mean age 9 years) were included. Mean BMI was 18.3 kg/m2 and mean fat mass was 24.9%. A large inter-subject variability was found with a weak correlation between BMI and fat mass percentage in children with a BMI < 20 kg/m2. Little agreement (k = 0.299, CI 0.16-0.44) between the categorization of children based on BMI and based on fat mass percentage was found.

INTERPRETATION

The large inter-subject variability in fat mass percentage combined with little agreement between the BMI and BIA categories suggests that BMI is not a suitable measure of fat mass in children with CP.IMPLICATIONS FOR REHABILITATIONUsing body mass index (BMI) and instead of fat mass percentage increases the risk of misclassifying body composition in children with spastic Cerebral Palsy.Children with a BMI < 20 kg/m2 are more at risk to be misclassified for body composition.

Fat-Free Mass Index for body composition analysis in pediatric sport: a cross-sectional study

BACKGROUND

Analyzing fat free mass (FFM) helps sport professionals during the prescription of sport training for children and adolescents in a sport initiation program. In this way, it is possible to determine fat mass (FM) (FFM subtracted from total body weight) and design interventions to increase FFM and reduce %F, making it possible to maximize performance in relation to the physical demands of sport. However, there is still no reliable anthropometric index to analyze FFM in this population. The aim the present study was to develop the Fat-Free Mass Index (FFMI) for pediatrics of both sexes.

METHODS

Cross-sectional study with a sample composed of 254 pediatrics (139 males [age: 13.0±2.3] and 115 females [age: 12.5±2.2]), from a sports initiation school. We divided the sample into the groups: 1) development (N.=169); and 2) cross-validation (N.=85). The body composition was analyzed by dual-energy X-ray absorptiometry (DXA), in addition we acquired anthropometric data (height, body weight and hip circumference) for the development of the FFMI - Pediatric (FFMIp). By means of linear regression we tested the predictive power of FFM using DXA as a reference method, then we developed FFMIp and tested its reliability and validity in relation to DXA.

RESULTS

FFMIp consisted of: -16.679 + (0.615 × body mass (kg)) - (2.601 × sex) + (0.618 × age(years)) - (0.332 × hip(cm)) + (0.278 × stature(cm)), where for sex 0 = male and 1 = female. For the FFM analysis, FFMIp showed no significant difference from DXA (P>0.05). It also showed significant accuracy (Cb>0.960), precision (ρ>0.990) and agreement (CCC>0.960) for both groups (development and cross-validation).

CONCLUSIONS

Pediatric FFMI proposed by this study proved to be valid for the analysis of fat-free mass in pediatric athletes of sports initiation of both sexes.

AI-Enhanced Analysis Reveals Impact of Maternal Diabetes on Subcutaneous Fat Mass in Fetuses without Growth Alterations

Pregnant women with diabetes often present impaired fetal growth, which is less common if maternal diabetes is well-controlled. However, developing strategies to estimate fetal body composition beyond fetal growth that could better predict metabolic complications later in life is essential. This study aimed to evaluate subcutaneous fat tissue (femur and humerus) in fetuses with normal growth among pregnant women with well-controlled diabetes using a reproducible 3D-ultrasound tool and offline TUI (Tomographic Ultrasound Imaging) analysis. Additionally, three artificial intelligence classifier models were trained and validated to assess the clinical utility of the fetal subcutaneous fat measurement. A significantly larger subcutaneous fat area was found in three-femur and two-humerus selected segments of fetuses from women with diabetes compared to the healthy pregnant control group. The full classifier model that includes subcutaneous fat measure, gestational age, fetal weight, fetal abdominal circumference, maternal body mass index, and fetal weight percentile as variables, showed the best performance, with a detection rate of 70%, considering a false positive rate of 10%, and a positive predictive value of 82%. These findings provide valuable insights into the impact of maternal diabetes on fetal subcutaneous fat tissue as a variable independent of fetal growth.

Evaluation of bioelectrical impedance analysis in measuring body fat in 6-to-12-year-old boys compared with air displacement plethysmography

Air displacement plethysmography (ADP) has been considered as the 'standard' method to determine body fat in children due to superior validity and reliability compared with bioelectrical impedance analysis (BIA). However, ADP and BIA are often used interchangeably despite few studies comparing measures of percentage body fat by ADP (%FMADP) with BIA (%FMBIA) in children with and without obesity. The objective of this study was to measure concurrent validity and reliability of %FMADP and %FMBIA in 6-to-12-year-old boys with and without obesity. Seventy-one boys (twenty-five with obesity) underwent body composition assessment. Ten boys participated in intra-day reliability analysis. %FMADP was estimated by Bodpod using sex- and age-specific equations of body density. %FMBIA was estimated by a multi-frequency, hand-to-foot device using child-specific equations based on impedance. Validity was assessed by t tests, correlation coefficients and limits of agreement (LoA); and reliability by technical error of measurement (TEM) and intraclass correlation coefficients (ICC). Compared with %FMADP, %FMBIA was significantly underestimated in the cohort (-3·4 ± 5·6 %; effect size = 0·42) and in both boys with obesity (-5·2 ± 5·5 %; ES = 0·90) and without obesity (-2·4 ± 5·5 %; ES = 0·52). A strong, significant positive correlation was found between %FMADP and %FMBIA (r = 0·80). Across the cohort, LoA were 22·3 %, and no proportional bias was detected. For reliability, TEM were 0·65 % and 0·55 %, and ICC were 0·93 and 0·95 for %FMBIA and %FMADP, respectively. Whilst both %FMADP and %FMBIA are highly reliable methods, considerable differences indicated that the devices cannot be used interchangeably in boys age 6-to-12 years.

A comparison of bioelectrical impedance analysis and air displacement plethysmography to assess body composition in children

Background

Accurate assessment of body composition (BC) is important to investigate the development of childhood obesity. A bioelectrical impedance analysis (BIA) device is portable and inexpensive compared with air displacement plethysmography (ADP) for the assessment of BC and is widely used in children. However, studies of the effectiveness of BIA are few and present different results, especially in pediatric populations. The aim of this study was to evaluate the agreement between BIA and ADP for estimating BC.

Methods

The BC of 981 Chinese children (3-5 years) was measured using the BIA device (SeeHigher BAS-H, China) and ADP (BOD POD).

Results

Our results showed that BIA underestimated fat mass (FM) and overestimated fat-free mass (FFM) in normal weight children (P < 0.05), but the opposite trend was shown in children with obesity (P < 0.05). The agreement between FM and FFM measured by the two methods was strong (CCC > 0.80). The linear regression equation of 5-year-old children was constructed.

Conclusion

The SeeHigher BAS-H multi-frequency BIA device is a valid device to evaluate BC in Chinese preschool children compared with ADP (BOD POD), especially in 5-year-old children or children with obesity. Further research is needed to standardize the assessment of BC in children.

Skinfold-based-equations to assess longitudinal body composition in children from birth to age 5 years

BACKGROUND & AIMS

In order to identify children at risk for excess adiposity, it is important to determine body composition longitudinally throughout childhood. However, most frequently used techniques in research are expensive and time-consuming and, therefore, not feasible for use in general clinical practice. Skinfold measurements can be used as proxy for adiposity, but current anthropometry-based-equations have random and systematic errors, especially when used longitudinally in pre-pubertal children. We developed and validated skinfold-based-equations to estimate total fat mass (FM) longitudinally in children aged 0-5 years.

METHODS

This study was embedded in the Sophia Pluto study, a prospective birth cohort. In 998 healthy term-born children, we longitudinally measured anthropometrics, including skinfolds and determined FM using Air Displacement Plethysmography (ADP) by PEA POD and Dual energy X-ray Absorptiometry (DXA) from birth to age 5 years. Of each child one random measurement was used in the determination cohort, others for validation. Linear regression was used to determine the best fitting FM-prediction model based on anthropometric measurements using ADP and DXA as reference methods. For validation, we used calibration plots to determine predictive value and agreement between measured and predicted FM.

RESULTS

Three skinfold-based-equations were developed for adjoined age ranges (0-6 months, 6-24 months and 2-5 years), based on FM-trajectories. Validation of these prediction equations showed significant correlations between measured and predicted FM (R: 0.921, 0.779 and 0.893, respectively) and good agreement with small mean prediction errors of 1, 24 and -96 g, respectively.

CONCLUSIONS

We developed and validated reliable skinfold-based-equations which may be used longitudinally from birth to age 5 years in general practice and large epidemiological studies.

Recreational screen time trajectories during early childhood and imaging-measured body composition at age 7 in the Odense child cohort

BACKGROUND

Children spend increasing amounts of time on recreational screen media, which may lead to an obesogenic environment.

OBJECTIVES

We investigated the association of trajectories of screen time across ages 3, 5 and 7 years with body composition at age 7 in the Odense Child Cohort.

METHODS

Data were collected in the Municipality of Odense, Denmark, between 2010 and 2019. Group-based trajectory modelling was applied to group participants into four trajectories of prospective parent-reported screen time. Body composition was assessed using dual-energy x-ray absorptiometry with calculated fat-mass index (FMI) as the primary outcome. Primary models were linear multivariable regression models adjusted for participants' sex, age, birthweight, maternal origin, maternal education, maternal body-mass-index, and maternal age. Further models were adjusted for additional possible confounders. Selection bias was addressed by inverse probability weighting.

RESULTS

In total, 803 children (48.2% female) were included in the primary analysis. Participants with screen time at all time points were assigned to four trajectory groups [constant low screen time (12.7%), low increase (36.3%), high increase between ages 3 and 5 (33.5%) and high increase in screen time (17.5%)]. Sample characteristics differed across missing data status and trajectories. Mean FMI (kg/m2 ) and standard deviation (SD) were 3.7 (SD 1.3) and 3.9 (SD 1.6) for the constant low versus high screen time, respectively. No differences in FMI were found between screen time trajectory groups at age 7 (adjusted mean difference 0.1 kg/m2 , 95% confidence interval -0.3, 0.5 for constant low versus high screen time). No consistent associations between screen time groups and secondary body composition outcomes were found.

CONCLUSIONS

Results from this study do not suggest that recreational screen time from age 3 to 7 years is associated with adiposity or other measures of body composition.

Cook with Different Pots, but Similar Taste? Comparison of Phase Angle Using Bioelectrical Impedance Analysis According to Device Type and Examination Posture

Bioelectrical impedance analysis (BIA) is gaining popularity as a tool for body composition assessment. Although BIA has been studied and validated in different populations, age groups, and clinical settings, including critically ill patients, there are concerns about BIA reproducibility and reliability for different device types and postures. This study aimed to evaluate the reliability of BIA using different devices, postures, and lead types. Cross-sectional observational data were collected from 74 healthy volunteers (32 women, 42 men). We used two types of devices, three types of postures (standing, sitting, and lying), and two lead types (clamp lead and adhesive lead) to measure the whole-body phase angle (phA) at a single frequency of 50 kHz. The measurements were validated using the intraclass correlation coefficient (ICC) and Bland-Altman plot analysis. All phA measurements recorded using the two types of devices, three different postures, and two types of leads were equivalent (mean ICC = 0.9932, 95% confidence interval (CI) 0.9905-0.0053, p < 0.001). The average mean difference in phA was 0.31 (95% CI 0.16-0.46). The largest phA value was measured using BWA with an adhesive-type lead in the supine position. There were no differences between the standing and sitting positions. We compared the consistency and reliability of phA using two devices, two lead types, and three postures. Seven different phA were interchangeable in healthy volunteers.

Overfat cutoffs and the optimal combination of body fat indices for detecting cardiometabolic risk among school-aged children

OBJECTIVE

This study aimed to develop cutoffs and the optimal combination for body fat indices for screening cardiometabolic risk (CMR) among the pediatric population.

METHODS

This cross-sectional study consisted of 8710 (50.3% boys) Chinese children aged 6 to 18 years. Body fat indices, including fat mass index (FMI), body fat percentage, trunk to leg fat ratio (TLR), and android to gynoid fat ratio, were derived from dual-energy x-ray absorptiometry scans. The area under the receiver operating characteristic curve was used to determine the best combination and optimal cutoffs of body fat indices to identify CMR.

RESULTS

Compared with anthropometry-based obesity measures, i.e., BMI and waist circumference, the FMI + TLR combination presented statistically higher area under the receiver operating characteristic curve values for discriminating CMR and its clustering. The optimal overfat cutoffs of FMI and TLR were respectively determined at the 75th percentile in boys and at the 80th percentile of FMI and the 75th percentile of TLR in girls. Moreover, simplified thresholds derived from age-group-merged cutoffs showed similar performance as optimal cutoffs in detecting CMR.

CONCLUSIONS

Both the optimal and simplified overfat cutoffs were provided for the Chinese pediatric population. The use of FMI and TLR together allows for adequate screening of CMR and its clustering.

Does incorporating high intensity interval training in physical education classes improve fitness outcomes of students? A cluster randomized controlled trial

The aim of this study was to determine the efficacy of a high intensity interval training (HIIT) intervention lasting 12 weeks on fitness (cardiorespiratory fitness, muscular strength, muscular endurance, power, speed, flexibility, and balance) and adiposity of 10- to 15-year-old students implemented during their physical education (PE). The focus of this study was to compare two approaches to increasing fitness level among school-aged children, one approach focusing on regular PE sessions in accordance with the curriculum and another one on regular PE classes augmented by HIIT. A cluster-randomized controlled trial was conducted (February-May 2022, Zagreb, Croatia). The total number of students across both groups was 207. General linear models were used to compare fitness and adiposity changes in both groups based on Eurofit test battery. A significant effect of the HIIT intervention was present for the 20-meter shuttle run test (p = 0.001; d = 0.31). The effect of the intervention compared to the control was estimated as an additional 181.2 m, 95 %CI (70.4 to 292.0). An additional intention-to-treat (ITT) analysis showed that the effect of the HIIT intervention on 20-meter shuttle run test remained statistically significant (p = 0.011), though the magnitude of the estimated effect was reduced from 181.2 m; SE = 55.4 to 119.6 m; SE = 46.4. Whilst it appears HIIT had the opposite of the expected effect on body fat percentiles, the effect on body composition was inconsistent. The intervention is registered at the Australian New Zealand Clinical Trials Registry (ANZCTR) [ACTRN12622000209796].

Relationship between fitness performance and a newly developed continuous body composition score in U.S. adolescent boys

OBJECTIVES

Body composition (BC) assessment typically requires the administration of a single test and can have different evaluation outcomes depending on the selected test and the specific population. The purpose of this study was twofold. Firstly, to develop and validate a novel continuous body composition (CBC) score using the continuous response model (CRM). Secondly, to examine the relationship between CBC scores and fitness performance.

METHODS

Data from the 2012 NHANES National Youth Fitness Survey (NNYFS) were used and consisted of n=212 adolescent boys 12-15 years of age. CBC scale variables included body mass (BM), body mass index (BMI), arm circumference (AC), waist circumference (WC), calf circumference (CC), calf skinfold (CSF), triceps skinfold (TSF), and subscapular skinfold (SSF). Fitness performance variables included cardiorespiratory fitness (CRF, mL/kg/min), leg strength (LS, lb), modified pull-ups (MPU, #), grip strength (GS, kg), and plank (PL, sec). Samejima's CRM, factor analysis, convergent validity coefficients and score reliability were used to validate the CBC scale. Multinomial logistic regression and multiple linear regression were used to examine the relationship between CBC scores and fitness performance variables.

RESULTS

Factor analysis of the CBC scale variables retained a single factor (loadings >0.81, 88% explained variance) with strong internal consistency (α=0.96). The CRM analysis indicated all CBC scale variables fit a unidimensional construct with adequate discrimination (as: 0.71-2.16) and difficulty (bs: -0.04-1.44). CBC scores (Mean=0, SD=1.00) displayed strong reliability (SEE.θ=0.22, r.θ=0.95) with lower values representing smaller-more-lean individuals and higher values representing larger-less-lean individuals. All fully adjusted regression models showed significant (ps<0.05) negative relationships between CBC scores and CRF, MPU, and PL and positive relationships between CBC scores and LS and GS.

CONCLUSION

The CRM-derived CBC score is a novel measure of BC and found to be positively associated with strength performance and negatively associated with endurance performance in U.S. adolescent boys.

Estimation of fat mass in Southern Brazilian female adolescents: development and validation of mathematical models

abstract This study aimed to develop and validate the first mathematical models, based on anthropometric properties, to estimate fat mass (FM) in a heterogeneous sample of female adolescents. A cross-sectional and quantitative study conducted with 196 individuals aged 12 to 17 years from the metropolitan region of Curitiba, Paraná, Brazil. The participants were randomly divided into two groups: regression sample (n = 169) and validation sample (n = 27). Dual-energy X-ray absorptiometry (DXA) was used as the reference method to determine body fat in relative and absolute values. Stature, body mass, waist girth and triceps, subscapular, biceps, iliac crest, abdominal, front thigh and medial calf skinfold thickness were defined as independent variables and measured according to an international technical protocol. Statistical analyzes used the Ordinary Least Square (OLS) regression model, paired t test and Pearson correlation. Four multivariate mathematical models with high determination coefficients (R2 ≥90%) and low estimated standard errors (SEE = ≤2.02 kg) were developed. Model 4 stands out for its low number of independent variables and significant statistical performance (R2 = 90%; SEE = 1.92 kg). It is concluded that the four mathematical models developed are valid for estimating FM in female adolescents in southern Brazil.

Body Composition and Spasticity in Children with Unilateral Cerebral Palsy-A Case-Control Study

The aim of this study was to identify the correlations between segmental body composition and the spasticity level of the affected lower limb in children with unilateral cerebral palsy (spastic hemiplegia). Additionally, an attempt was made to identify the differences in composition between the affected and unaffected lower limbs using segmental body composition analysis. This case-control study included 31 children with spastic hemiplegia aged 8 to 16 years with differing severities of spasticity in the lower limbs. The reference group consisted of a control group which included 31 peers with corresponding age and sex to the tested group. Negative correlations obtained in the statistical analysis showed that higher spasticity level in the iliopsoas muscle is associated with lower limb fat-free mass and lower limb muscle mass. Our results showed that children with spastic hemiplegia have worse parameters of body composition in the affected limb than in the unaffected one. To confirm the importance of these results, further studies are needed in a larger population which includes non-ambulatory children.

Relation between obesity-related comorbidities and kidney function estimation in children

BACKGROUND

The current childhood obesity pandemic is likely to result in an increased risk of chronic kidney disease (CKD) later in life. Correlations between obesity-related comorbidities and kidney function can be found, but it is unclear to what extent this is caused by bias due to different mathematical forms of the estimated glomerular filtration rate (eGFR) equations. The present study aimed to analyze correlations between obesity-related comorbidities and different eGFR equations and to investigate whether rescaled serum creatinine (SCr/Q) for sex and age or height might be an alternative biomarker for kidney function estimation.

METHODS

This cross-sectional cohort study included 600 children with overweight and obesity. Mean age was 12.20 ± 3.28 years, 53.5% were female, and mean BMI z-score was 3.31 ± 0.75. All children underwent a comprehensive assessment that included anthropometrical and blood pressure measurements, laboratory examination, air displacement plethysmography, and polysomnography. Qage and Qheight polynomials were used to rescale SCr and multiple creatinine-based eGFR equations were compared.

RESULTS

SCr/Q and almost all GFR estimations significantly correlated with a waist-to-hip ratio, fat mass, homeostasis model assessment for insulin resistance, and triacylglyceride, HDL cholesterol, alanine transaminase, and serum uric acid concentrations. Multiple correlations, however, were not confirmed by all equations, which suggests dependency on the mathematical form of the different eGFR equations.

CONCLUSIONS

Correlations between obesity-related comorbidities and creatinine-based eGFR are present in children with overweight and obesity, but depend to a large extent on the eGFR equation of choice. SCr/Q might be an alternative biomarker for assessing correlations between obesity-related comorbidities and kidney function in children with overweight and obesity. A higher resolution version of the Graphical abstract is available as Supplementary information.

Childhood Obesity: Position Statement of Polish Society of Pediatrics, Polish Society for Pediatric Obesity, Polish Society of Pediatric Endocrinology and Diabetes, the College of Family Physicians in Poland and Polish Association for Study on Obesity

Childhood obesity is one of the most important problems of public health. Searching was conducted by using PubMed/MEDLINE, Cochrane Library, Science Direct, MEDLINE, and EBSCO databases, from January 2022 to June 2022, for English language meta-analyses, systematic reviews, randomized clinical trials, and observational studies from all over the world. Five main topics were defined in a consensus join statement of the Polish Society of Pediatrics, Polish Society for Pediatric Obesity, Polish Society of Pediatric Endocrinology and Diabetes and Polish Association for the Study on Obesity: (1) definition, causes, consequences of obesity; (2) treatment of obesity; (3) obesity prevention; (4) the role of primary care in the prevention of obesity; (5) Recommendations for general practitioners, parents, teachers, and regional authorities. The statement outlines the role of diet, physical activity in the prevention and treatment of overweight and obesity, and gives appropriate recommendations for interventions by schools, parents, and primary health care. A multisite approach to weight control in children is recommended, taking into account the age, the severity of obesity, and the presence of obesity-related diseases. Combined interventions consisting of dietary modification, physical activity, behavioral therapy, and education are effective in improving metabolic and anthropometric indices. More actions are needed to strengthen the role of primary care in the effective prevention and treatment of obesity because a comprehensive, multi-component intervention appears to yield the best results.

Sociodemographic and Socioeconomic Factors Influencing the Body Mass Composition of School-Age Children

The purpose of the study was to evaluate the components of overweight, obesity, and body mass components among children aged 7 to 13 years against important sociodemographic factors. The analyses considered 315 school-age children from 7 to 13 years of age (164 boys and 151 girls). Each subject was assessed for body weight and height, body weight category, and main sociodemographic factors. Body mass components of body mass (body-fat percentage (BFP), muscle tissue, fat-free mass (FFM), and total body water (TBW) levels) were evaluated using the electrical bioimpedance method (BIA) and the TANITA 780 MC analyzer. A statistical analysis showed significant differences between the body composition of children living in cities in relation to children living in small towns and villages, and no significant differences were found between the results of children living in small towns and children living in villages. The presence of statistically significant differences between the values of the parameters of body composition of the studied children was demonstrated depending on the level of education of their fathers. The presence of statistically significant relationships between BMI of mothers and BFP of their children (p = 0.003), FFM (p = 0.003), muscle tissue (p = 0.001), and TBW (p = 0.001) has been demonstrated. The higher content of adipose tissue in children is strongly dependent on the higher BMI and body mass category of the mother, as well as the lower level of education of the father. The place of residence also significantly affects both the body fat content and the total body water content of body hydration. Living in the city is associated with better body composition.

Markers of obesity in Danish pediatric liver transplantation recipients

BACKGROUND

Long-time survivors of pediatric liver transplantation have an increased incidence of the metabolic syndrome. Adult recipients have an increased risk of post-transplantation obesity; however, pediatric data are limited.

METHODS

The study included 42 recipients of pediatric liver transplantation in Denmark, transplanted between 1990 and 2014. The study participants were examined with anthropometric measures, dual-energy X-ray scans and blood samples. From the anthropometric measures, body mass index (BMI) and BMI standard deviation score (SDS) were calculated. From the dual-energy X-ray scans, fat percent was assessed, and body fat mass index (BFMI) was calculated.

RESULTS

The median age was 17.4 years (range 4.1-38.9) at the time of the study, and the median time since transplantation was 8.5 years (range 0.4-23.9). The prevalence of overweight and obesity was 31.0% based on BMI SDS (age below 18) and BMI (age 18 and above). When compared to the participants with normal weight, the participants with overweight and obesity had a higher BFMI (9.29 vs 5.57 kg/m² , p < .001) and fat percent (38.35% vs 29.50%, p = .006). They had higher levels of total cholesterol (4.3 vs 3.6 mmol/L, p = .023) and low-density lipoprotein (2.5 vs 1.7, p = .015), and had had longer time since transplantation (15.6 vs 8.5 years respectively, p = .045).

CONCLUSIONS

Long-time survivors of pediatric liver transplantation have a higher BMI or BMI SDS than the general pediatric population. The obesity is characterized by a higher BFMI, fat percent, and cholesterols levels, when compared to recipients without overweight or obesity.

Predicting of excess body fat in children

PURPOSE OF REVIEW

Approximately 370 million children and adolescents worldwide showed overweight or obesity in 2016. The risk of developing severe comorbidities depends on the age of onset and the duration of obesity. This review discusses available methodologies to detect excess body fat in children as well as the early life factors that predict excess body fat and its development.

RECENT FINDINGS

Factors, such as parental nutritional status, maternal weight gain during pregnancy, maternal malnutrition, maternal smoking during pregnancy, low and high birth weight, rapid weight gain, and short infant sleep duration have been independently and positively associated with neonatal, infant, and children adiposity. Early detection of excess body fat in children through the use of various tools is the first step in preventing nutrition-related diseases in adulthood.

SUMMARY

The early detection of excess body fat and the implementation of efficient interventions to normalize the weight of children and adolescents at obesity risk are essential to prevent diseases in adult life.

Differences in body composition and physical fitness parameters among prepubertal and pubertal children engaged in extracurricular sports: the active health study

Background

This study aimed to analyze the associations of maturity status, chronological age and sex with physical fitness and body composition among active children.

Methods

A total of 1682 children (72% boys; age = 11.22 ± 2.64 years; height = 147.57 ± 15.87 cm; weight = 44.55 ± 15.29 kg) from rural areas participating in extracurricular sports were divided into four groups according to their sex and maturity status (prepubertal and pubertal according to stages described by Tanner). Body composition (body mass index, muscle mass and fat mass) and physical fitness (20-m shuttle-run test, handgrip strength and vertical jump) were assessed using standardized procedures. A two-way ANOVA and product–moment correlations were performed.

Results

Prepubertal boys had more fat mass (%) than pubertal boys [P<0.001; effect size (ES): 0.45], while prepubertal girls had more muscle mass (%) than pubertal girls (P<0.001; ES: 0.47). The pubertal group displayed higher fitness outcomes (absolute values) regardless of sex (P<0.05). However, the prepubertal group had higher percentile values in the 20-m shuttle-run test and vertical jumps than the pubertal group regardless of sex (P < 0.001; ES: 0.29–0.48). All the measures of physical fitness were positively associated with chronological age and muscle mass (%).

Conclusions

Although absolute values of body composition and physical fitness appear to increase among pubertal children participating in extracurricular sports, the percentiles indicate that puberty is accompanied with a loss of a physical fitness levels. Thus, extracurricular sports might not be enough to enhance fitness among adolescents.

Metagenomic analysis reveals associations between salivary microbiota and body composition in early childhood

Several studies have shown that body mass index is strongly associated with differences in gut microbiota, but the relationship between body weight and oral microbiota is less clear especially in young children. We aimed to evaluate if there is an association between child growth and the saliva microbiome. We hypothesized that associations between growth and the saliva microbiome would be moderate, similarly to the association between growth and the gut microbiome. For 236 toddlers participating in the New Hampshire Birth Cohort Study, we characterized the association between multiple longitudinal anthropometric measures of body height, body weight and body mass. Body Mass Index (BMI) z-scores were calculated, and dual-energy x-ray absorptiometry (DXA) was used to estimate body composition. Shotgun metagenomic sequencing of saliva samples was performed to taxonomically and functionally profile the oral microbiome. We found that within-sample diversity was inversely related to body mass measurements while community composition was not associated. Although the magnitude of associations were small, some taxa were consistently associated with growth and modified by sex. Certain taxa were associated with decreased weight or growth (including Actinomyces odontolyticus and Prevotella melaninogenica) or increased growth (such as Streptococcus mitis and Corynebacterium matruchotii) across anthropometric measures. Further exploration of the functional significance of this relationship will enhance our understanding of the intersection between weight gain, microbiota, and energy metabolism and the potential role of these relationships on the onset of obesity-associated diseases in later life.

Differences between Four Skinfold Calipers in the Assessment of Adipose Tissue in Young Adult Healthy Population

Background: The aim of this study was to analyze the validity of four different skinfold calipers, as well as to establish the differences between them in a healthy young adult population. Methods: The present study followed a cross-sectional design, including 138 participants, with 69 males (21.46 ± 2.52 years) and 69 females (22.19 ± 2.85 years). The measurement protocol included basic measurements of body mass and stretch stature and eight skinfolds with a Harpenden, Holtain, Slim Guide, and Lipowise. The ∑6 and ∑8 skinfolds and fat mass were calculated. The order in which the skinfold calipers were used was randomized. Results: No significant differences were found in either the Σ6 and Σ8 skinfolds or masses and fat percentages calculated with the skinfolds obtained with the different calipers (p > 0.05), and the inclusion of the covariates of sex, BMI, and hydration status of the participants showed no effect on the differences. The Bland−Altman test showed significant differences between the calipers (p < 0.001). Conclusion: It has been observed that the analyzed calipers have shown validity for the assessment of adiposity-related variables in a male and female sample of non-overweight, young healthy adults, but they are not interchangeable with each other when the assessment is meant to be compared over time or with other samples.

Using bioelectrical impedance analysis in children and adolescents: Pressing issues

Single- and multifrequency bioelectrical impedance analysis (BIA) has gained popularity as a tool to assess body composition and health status of children and adolescents, but many questions and misconceptions remain. This review addresses pressing issues researchers and health care providers may encounter when using BIA in the young population. The importance of choosing population-specific and device-specific equations to estimate body composition as well as the use of BIA in longitudinal analyses are discussed. When specific equations are not available, raw bioimpedance values (i.e., resistance, reactance, and impedance) can be used to compute bioimpedance parameters, such as phase angle, impedance ratio, and bioelectrical impedance vector analysis. As interpreting these parameters is challenging, suggestions are provided on the use of reference data, cut-off points, and adjustment factors. Furthermore, unsolved technical and analytical issues are listed. Based on existing issues and potential for future development, a greater interaction between industry and academic researchers to improve the validity of BIA measurements among children and adolescents across their developmental stages is encouraged.

Association between Cardiopulmonary Capacity and Body Mass Composition in Children and Adolescents with High Body Weight: A Cross-Sectional Study

(1) Background: Excessive body weight is a global problem in the 21st century. Children and adolescents, in particular, are at risk. Recently, there has been an increasing interest in the relationship between aerobic capacity and body composition. Therefore, this study aimed to determine the association between the individual parameters of cardiopulmonary capacity obtained in cardiopulmonary exercise testing (CPET) and selected parameters of body mass composition in high-BMI children and children over the 85th percentile according to the WHO growth reference. (2) Materials and Method: The research included 100 children of school-age (7-15 years) with an excessive BMI, i.e., over the 85th percentile as per the WHO Growth Reference (BMI percentile 95.21 ± 4.65; Z-score BMI: 2.07 ± 0.94). The study consisted of three parts: anthropometric measurements, measurement of body mass composition using a body composition analyzer (TANITA MC-780 S MA) using the bioimpedance method, and a cardiopulmonary exercise test on a pediatric cycle ergometer (Corival Pediatric, Lode BV) using the Godfrey protocol; (3) Results: The correlation between BMI and fat mass (FM) was very high (rho = 0.83; p = 0.00) with moderate body fat percentage (BF%) (rho = 0.48; p = 0.00). There was a relevant correlation between the amount of fat-free mass in total body mass and cardiopulmonary capacity expressed as the absolute aerobic capacity (VO2peak) (rho = 0.55; p = 0.00). (4) Conclusions: In the case of children and youth with higher BMI, there was a correlation between the amount of fat-free mass in total body mass and cardiopulmonary capacity in terms of absolute aerobic capacity.

Official Position of the Brazilian Association of Bone Assessment and Metabolism (ABRASSO) on the evaluation of body composition by densitometry-part II (clinical aspects): interpretation, reporting, and special situations

OBJECTIVE

To present an updated and evidence-based guideline for the use of dual-energy x-ray absorptiometry (DXA) to assess body composition in clinical practice.

MATERIALS AND METHODS

This Official Position was developed by the Scientific Committee of the Brazilian Association of Bone Assessment and Metabolism (Associação Brasileira de Avaliação Óssea e Osteometabolismo, ABRASSO) and experts in the field who were invited to contribute to the preparation of this document. The authors searched current databases for relevant publications in the area of body composition assessment. In this second part of the Official Position, the authors discuss the interpretation and reporting of body composition parameters assessed by DXA and the use of DXA for body composition evaluation in special situations, including evaluation of children, persons with HIV, and animals.

CONCLUSION

This document offers recommendations for the use of DXA in body composition evaluation, including indications, interpretation, and applications, to serve as a guiding tool in clinical practice and research for health care professionals in Brazil.

Body Composition Assessment by Air-Displacement Plethysmography Compared to Dual-Energy X-ray Absorptiometry in Full-Term and Preterm Aged Three to Five Years

It is important to monitor body composition longitudinally, especially in children with atypical body composition trajectories. Dual-energy X-ray absorptiometry (DXA) can be used and reference values are available. Air-displacement plethysmography (ADP) is a relatively new technique, but reference values are lacking. In addition, estimates of fat-free mass density (Dffm), needed in ADP calculations, are based on children aged >8 years and may not be valid for younger children. We, therefore, aimed to investigate whether DXA and ADP results were comparable in young children aged 3−5 years, either born full-term or preterm, and if Dffm estimates in the ADP algorithm could be improved. In 154 healthy children born full-term and 67 born < 30 weeks of the inverse pressure-volume gestation, aged 3−5 years, body composition was measured using ADP (BODPOD, with default Lohman Dffm estimates) and DXA (Lunar Prodigy). We compared fat mass (FM), fat mass percentage (FM%) and fat-free mass (FFM), between ADP and DXA using Bland−Altman analyses, in both groups. Using a 3-compartment model as reference method, we revised the Dffm estimates for ADP. In full-term-born children, Bland−Altman analyses showed considerable fixed and proportional bias for FM, FM%, and FFM. After revising the Dffm estimates, agreement between ADP and DXA improved, with mean differences (LoA) for FM, FM%, and FFM of −0.67 kg (−2.38; 1.04), −3.54% (−13.44; 6.36), and 0.5 kg (−1.30; 2.30), respectively, but a small fixed and proportional bias remained. The differences between ADP and DXA were larger in preterm-born children, even after revising Dffm estimates. So, despite revised and improved sex and age-specific Dffm estimates, results of ADP and DXA remained not comparable and should not be used interchangeably in the longitudinal assessment of body composition in children aged 3−5 years, and especially not in very preterm-born children of that age.

Physical activity is associated with lower pulsatile stress but not carotid stiffness in children

The cardiovascular disease (CVD) process may begin early in life when accompanied by atherosclerotic risk factors. CVD risk factors in children are associated with stiffening of the large elastic arteries, a reflection of subclinical atherosclerosis. Physical activity is a preventative lifestyle strategy that may benefit arterial stiffness by attenuating the hemodynamic stress on the artery wall. This study examined the relations between physical activity, carotid pulsatile stress, and carotid stiffness in children. One hundred and forty children (9-11 yrs; 50.0% male, 57.9% African-American, 42.10% Caucasian, body mass index (BMI) 20.1 ± 4.7 kg/m2) participated in this study. Physical activity counts were measured using a wrist-worn accelerometer and averaged over 7 days. Carotid artery β-stiffness and pulse pressure (calibrated to brachial mean and diastolic pressure) were assessed as via ultrasound and tonometry, respectively. Pulsatile stress was calculated as the product of carotid pulse pressure and heart rate. Physical activity counts were correlated with pulsatile stress (r = -0.27), and BMI (r = -0.23), but were unrelated to carotid stiffness. In multivariate models, associations between physical activity counts and pulsatile stress remained (B = -1.3 [95%CI, -2.4, -0.2], β = -0.20, p < 0.05) after covariate adjustment for age, race, sex, pubertal stage, and BMI. Carotid pulsatile stress was related to regional carotid stiffness (r = 0.45, p < 0.05). These data suggest that higher levels of physical activity at young age are associated with lower hemodynamic stress in the carotid artery. Findings are discussed in the context of an inverse relationship between hemodynamic pulsatile stress and carotid stiffness in children.

Body composition and bone mineral density by Dual Energy X-ray Absorptiometry: Reference values for young children

BACKGROUND & AIMS

Childhood obesity is a global public health threat, with an alarming rise in incidence. Obesity at young age has short-term and long-term morbidity. It is, therefore, important to accurately assess body composition throughout infancy and childhood to identify excess adiposity. However, reference values for age 2-5 years, needed to interpret measurements and identify young children at risk, are lacking. Our primary objective was to fill the current gap in reference values by constructing sex-specific body composition reference values and charts for fat mass (FM), fat mass percentage (FM%), fat mass index (FMI), lean body mass (LBM), lean body mass index (LBMI) and total body less head bone mineral density (BMD_TBLH) for children aged 2-5 years using Dual-Energy X-ray Absorptiometry (DXA).

METHODS

We performed 599 accurate DXA-measurements in 340 term-born children aged 2-5 years, using Lunar Prodigy with Encore software (V14.1). Using GAMLSS, sex-specific reference values and charts were created for FM, FM%, FMI, LBM, LBMI and BMD_TBLH.

RESULTS

Sex-specific body composition reference values and charts for age 2-5 years were constructed. In boys and girls, FM and LBM increased from age 2-5 years (all p ≤ 0.001), but body size-corrected FM% and FMI decreased (all p ≤ 0.023). LBMI remained similar between 2 and 5 years of age. Girls had higher FM, FM% and FMI and lower LBM and LBMI compared to boys. BMC and BMD_TBLH increased with age between 2 and 5 years of age (all p < 0.001) and were similar for boys and girls.

CONCLUSIONS

We present sex-specific reference values and charts for body composition and total body bone mineral density measured by DXA, based on a large cohort of healthy children aged 2-5 years. These longitudinal references can be used for clinical practice and research purposes to monitor body composition and bone mineral density development and identify children at risk for excess adiposity.

25 Years of Research in Human Lactation: From Discovery to Translation

Researchers have recently called for human lactation research to be conceptualized as a biological framework where maternal and infant factors impacting human milk, in terms of composition, volume and energy content are studied along with relationships to infant growth, development and health. This approach allows for the development of evidence-based interventions that are more likely to support breastfeeding and lactation in pursuit of global breastfeeding goals. Here we summarize the seminal findings of our research programme using a biological systems approach traversing breast anatomy, milk secretion, physiology of milk removal with respect to breastfeeding and expression, milk composition and infant intake, and infant gastric emptying, culminating in the exploration of relationships with infant growth, development of body composition, and health. This approach has allowed the translation of the findings with respect to education, and clinical practice. It also sets a foundation for improved study design for future investigations in human lactation.

The Effects of Football Practice on Nutritional Status and Body Composition in Children: A Systematic Review and Meta-Analysis

Dietary patterns, exercise, sport, and physical activity have been shown to improve body composition in children. This systematic review with meta-analysis analyzed the effects of practicing football on body composition (fat mass, lean body mass, and bone mineral content) in children. An initial search in PubMed, Web of Science, and SPORTDiscus was carried out in April 2021 to identify relevant articles. Inclusion criteria required children up to 12 years of age with a minimum football intervention duration of 10 weeks. Methodological quality of the articles was evaluated using the PEDro scale. Between the 1803 articles originally founded, only 14 articles were included in the meta-analysis. A total of 1643 subjects between the 14 studies were identified. The review and meta-analysis were conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and used Review Manager and Full Meta-Analysis software. The results between the control and experimental groups showed significantly better lean body mass and fat mass values in the experimental group (p < 0.05). Football practice was positively associated with increases in lean body mass (mean difference of 1.55; 95% CI, 0.96, 2.15), decreases in fat mass (mean difference of -0.81; 95% CI, -1.49, -0.13), and increases in whole body bone mineral content (mean difference of 117.68; 95% CI, 83.69, 151.67). In conclusion, the results of this systematic review with meta-analysis suggest that football positively affects body composition in children. However, further research is needed to confirm the results for bone mineral content.

What Links Maternal Prepregnancy BMI to Early Childhood BMI: A Serial Mediation Analysis

OBJECTIVE

The aim of this study was to explore the potential impact of maternal gestational weight gain (GWG), infant birth weight, and postnatal weight change (ΔWAZ) on the relationship between maternal prepregnancy BMI (ppBMI) and childhood BMI.

METHODS

This retrospective cohort study analyzed a data set from Wuhan, China. The mediation effect of targeted mediators on the association between maternal BMI and childhood BMI at the age of 2 years was analyzed.

RESULTS

In the mediation model comprising maternal GWG, infant birth weight, and the first-6-month ΔWAZ as mediators of the association between ppBMI and children's BMI, the per unit increase in ppBMI resulted in a 0.01-kg/m² increase in children's BMI, through all three mediators. For the model comprising infant birth weight and the first-6-month ΔWAZ as mediators but maternal GWG as a moderator, the indirect effects of the first-6-month ΔWAZ on the relationship between ppBMI and childhood BMI was 0.0018 higher when maternal GWG increased from average values to 1 SD above the average values.

CONCLUSIONS

Maternal GWG, infant birth weight, and the first-6-month ΔWAZ mediated the effects of maternal ppBMI on children's BMI. Interventions targeting these factors can mitigate the risk of childhood obesity.

Body composition monitoring in children and adolescents: reproducibility and reference values

There is an increasing need for suitable tools to evaluate body composition in paediatrics. The Body Composition Monitor (BCM) shows promise as a method, but reference values in children are lacking. Twenty children were included and measured twice by 4 different raters to asses inter- and intra-rater reproducibility of the BCM. Reliability was assessed using the Bland-Altman method and by calculating intraclass correlation coefficients (ICCs). The intra-rater ICCs were high (≥ 0.97) for all parameters measured by BCM as were the inter-rater ICCs for all parameters (≥ 0.98) except for overhydration (0.76). Consequently, a study was set up in which BCM measurements were performed in 2058 healthy children aged 3-18.5 years. The age- and gender-specific percentile values and reference curves for body composition (BMI, waist circumference, fat mass and lean tissue mass) and fluid status (extracellular and intracellular water and total body water) relative to age were produced using the GAMLSS method for growth curves.Conclusion: A high reproducibility of BCM measurements was found for fat mass, lean tissue mass, extracellular water and total body water. Reference values for these BCM parameters were calculated in over 2000 children and adolescents aged 3 to 18 years. What is Known • The 4-compartment model is regarded as the 'gold standard' of body composition methods, but is inappropriate for regular follow-up or screening of large groups, because of associated limitations. • Body Composition Monitor® is an inexpensive field method that has the potential to be an adequate monitoring tool. What is New • Good reproducibility of BCM measurements in children provides evidence to use the device in longitudinal follow-up, multicentre and comparative studies. • Paediatric reference values relative to age and sex for the various compartments of the body are provided.

Obesity and Metabolic Care of Children of South Asian Ethnicity in Western Society

South Asians constitute one-fourth of the world’s population and are distributed significantly in western countries. With exponentially growing numbers, childhood obesity is of global concern. Children of South Asian ancestry have a higher likelihood of developing obesity and associated metabolic risks. The validity of commonly used measures for quantifying adiposity and its impact on metabolic outcomes differ by race and ethnicity. In this review we aim to discuss the validity of body mass index (BMI) and other tools in screening for adiposity in South Asian children. We also discuss the prevalence of overweight and obesity amongst South Asian children in western countries and the differences in body fat percentage, adiposity distribution, and metabolic risks specific to these children compared to Caucasian children. South Asian children have a characteristic phenotype: lower lean mass and higher body fat percentage favoring central fat accumulation. Hence, BMI is a less reliable predictor of metabolic status in these children than it is for Caucasian children. Furthermore, the relatively lower birth weight and rapid growth acceleration in early childhood of South Asian children increase the risk of their developing cardiometabolic disorders at a younger age than that of Caucasians. We emphasize the need to use modified tools for assessment of adiposity, which take into consideration the ethnic differences and provide early and appropriate intervention to prevent obesity and its complications.

Sociodemographic Correlates of Obesity among Spanish Schoolchildren: A Cross-Sectional Study

Some studies have been conducted in order to assess the association between weight status (assessed by body mass index) and socio-demographic factors. Nevertheless, only a few of them have indicated these associations by other anthropometric parameters (e.g., skinfolds). The aim of this study was to determine, compare, and examine the influence of age, sex, type of the schooling, per capita income, area of residence, and immigrant status on obesity parameters in schoolchildren aged 6-13 from the Region of Murcia. A cross-sectional study was carried out in six different Primary schools of the Region of Murcia (Spain). A total sample of 370 children (166 girls) aged 6-13 (8.7 ± 1.8) were selected. In order to determine participants' body composition, body mass index, waist circumference, waist-to-height ratio, and skinfold measurements were calculated. Higher associations of excess of weight (OR = 1.96; 95%CI = 1.19-3.20) and abdominal obesity (OR = 3.12; 95CI% = 1.49-6.94) were shown in the case of children from public schools. A greater association of high trunk fat mass was found in children from municipalities with high per capita income (OR = 3.20; 95%CI = 1.05-9.77). Therefore, lower association of having an inadequate %BF was found in the participants aged 6-9 (OR = 0.38; 95%CI = 0.24-0.54), and immigrant students (OR = 2.63; 95%CI = 1.69-4.10). Our study suggested that overweight/obesity among schoolchildren in the Region of Murcia is higher than the overall prevalence of Spain. The results of the adjusted analyses showed that age, type of schooling, per capita income, and immigrant status were associated with obesity parameters.

New insights on how and where to measure muscle mass

PURPOSE OF REVIEW

This article will discuss different muscle mass assessment methods and emphasize their highlights.

RECENT FINDINGS

Several measurement techniques can be used to evaluate muscle mass, recognized as important prognostic markers for adverse functional and clinical outcomes. Choosing the best method depends on the knowledge regarding their theoretical and practical limitations and the purpose of the assessment. Image techniques are considered the gold standards, with good accuracy and precision, but not always available in clinical settings. A new biological technique, the D3-creatinine dilution, can provide not only direct information about muscle mass but also shows a strong association with physical function. With the advancement of the use of the computed tomography (CT) images to assess skeletal muscle mass, mainly in patients with cancer, the assessment of skeletal muscle radiodensity (SMD), as a marker of muscle quality, may provide additional information regarding the association between muscle composition, muscle function and prognosis. Additional muscle function assessment can improve the risk prediction in several clinical situations.

SUMMARY

The use of the best tool for the muscle mass assessment should be performed carefully among the various methodologies, according to their characteristics and clinical situation.

Adipose Tissue Development and Expansion from the Womb to Adolescence: An Overview

Prevalence rates of pediatric obesity continue to rise worldwide. Adipose tissue (AT) development and expansion initiate in the fetus and extend throughout the lifespan. This paper presents an overview of the AT developmental trajectories from the intrauterine period to adolescence; factors determining adiposity expansion are also discussed. The greatest fetal increases in AT were observed in the third pregnancy trimester, with growing evidence suggesting that maternal health and nutrition, toxin exposure, and genetic defects impact AT development. From birth up to six months, healthy term newborns experience steep increases in AT; but a subsequent reduction in AT is observed during infancy. Important determinants of AT in infancy identified in this review included feeding practices and factors shaping the gut microbiome. Low AT accrual rates are maintained up to puberty onset, at which time, the pattern of adiposity expansion becomes sex dependent. As girls experience rapid increases and boys experience decreases in AT, sexual dimorphism in hormone secretion can be considered the main contributor for changes. Eating patterns/behaviors and interactions between dietary components, gut microbiome, and immune cells also influence AT expansion. Despite the plasticity of this tissue, substantial evidence supports that adiposity at birth and infancy highly influences its levels across subsequent life stages. Thus, a unique window of opportunity for the prevention and/or slowing down of the predisposition toward obesity, exists from pregnancy through childhood.