Measurement Of Percentage Body Fat Research Articles

Brief communication: body composition and hidden obesity in people living with HIV on antiretroviral therapy

BackgroundIncreased incidence of lifestyle diseases as side-effects of antiretroviral therapy (ART) have been reported in people living with HIV (PLWH). Few studies have evaluated obesity and hidden obesity in Japanese PLWH and their association with ART. In order to provide more appropriate drug selection and lifestyle guidance, we investigated the relationship between the effects of HIV infection and ART on the body composition of Japanese PLWH.MethodsPLWH who visited the outpatient clinic and had body composition measured using the body composition analyzer InBody 570 were included in this study. Medications, comorbidities, and blood test data were obtained. Body mass index (BMI), body fat percentage, and skeletal muscle mass index (SMI) were measured.ResultsIn this study, 543 patients were included. Based on body shape, patients were classified into a thin group (13), normal weight group (14), hidden obesity group (158), apparent obesity group (14), and obesity group (218). Compared with the normal weight group, the hidden obesity group had a higher prevalence of comorbidities and a lower SMI.ConclusionsPLWH are more likely to have obesity than the general population, indicating that hidden obesity is common even among those with a normal BMI. It is important to measure body fat percentage along with body weight, as hidden obesity can be missed. Further investigation of the effects of ART on body composition is needed.

Validity and reliability of portable A-mode ultrasound in measuring body fat percentage: A systematic review with meta-analysis.

The present Systematic Review with Meta-analysis study aimed to evaluate the validity and reliability of the Portable A-mode Ultrasound (P-US) for measuring body fat percentage (BF%). Only studies with participants of both genders which had assessed BF% using P-US compared to the reference standard were selected. Publications up until May 31, 2022 were searched in the MEDLINE, COCHRANE, Science Direct, Web of Science, LILACS, SciELO, PEDro, SPORT Discus, CINAHL and SCOPUS databases. QUADAS-2 was used to assess the risk of bias in the validity studies and QAREL was used for the methodological quality of reliability studies. The JAMOVI software program synthesized the results, from which the Pearson Correlation Coefficient (r) or the square root of the Multiple Linear Regression Determination Coefficient (R2) were extracted for the validity studies, and the Mean of Errors of the Bland-Altman Test (ME) and the Confidence Interval (95%CI) with Upper and Lower Limits for the reliability studies. A total of 13 studies were included, generating 26 results for the quantitative synthesis, 14 for validity and 12 for reliability. Regarding the validity results, a strong correlation was identified between the equipment (r = 0.870 [0.845-0.895], P<0.001), with moderate and true heterogeneity (I2 = 53.47%, P = 0.003), presenting publication bias. A small effect size was identified regarding the reliability results, overestimating the results due to chance between the devices (ME = 0.207 [-0.798-1.212], P = 0.686), with low heterogeneity also due to chance (I2 = 19.44%, P = 0.253), with no publication bias. All of the evaluated studies showed some violation of the instruments, confirming the high risk of bias and the low methodological quality. There is concern with heterogeneity for the validity results explained by the subgroups' analysis. The P-US associated with anthropometric perimeters satisfactorily measures the BF% with samples greater than 100 participants, and males. The results in the reliability assessment show high agreement and high variability, greatly expanding the confidence interval, which should be viewed with reservations. This review received financial support from the Brazilian Air Force. The study was registered with PROSPERO under the number CRD42020166617.

Characteristics of bone mineral density in patients with functional hypothalamic amenorrhoea and its association with reproductive hormones and body composition.

Bone mineral density (BMD) is typically reduced in patients with female athlete triad (FAT) and anorexia nervosa (AN). However, bone health in most patients with functional hypothalamic amenorrhoea (FHA), who may not suffer from severe energy deficiency, has not received adequate attention in clinical practice. This study aimed to investigate BMD and its association with clinical and endocrine features in individuals with FHA and to provide clinical evidence for improving bone loss and preventing osteoporosis in FHA. To assess the bone status of patients with FHA and investigate its association with various clinical and endocrinological characteristics. We retrospectively analysed 80 patients with FHA who attended the Obstetrics and Gynecology Hospital of Fudan University from January 2022 to March 2023. The levels of reproductive hormones, including luteinising hormone (LH), follicle-stimulating hormone, oestradiol (E2 )and total testosterone (TT), were examined at the time of initial diagnosis, and a body composition analyser was used to measure body fat percentage (BF%), lean body mass (LBM)and segmental muscle/fat. Dual-emission X-ray absorptiometry was used to measure lumbar spine BMDand femoral neck BMDin patients with FHA, and the Z score was calculated. The study cohort consisted of 80 female patients with FHA. The average age of the patients was 24.64 ± 6.02 years, and their body mass index (BMI) was 19.47 ± 2.86 kg/m2 . The duration of weight loss was 12 (6, 24) months, while the duration of oligo/amenorrhoea was 12 (4.5, 24) months. The mean degree of weight loss was 18.39 ± 9.53%. Low BMD were present in 15% of patients with FHA at the lumbar spine and/or femoral neck; 12.5% and 10% had low bone mass at the lumbar spine and femoral neck, respectively. The low bone mass group experienced a longer period of weight loss than the normal group [24 (16.5, 60) vs. 12 (4.5, 24) months, p = .037]. In addition, the abnormal group had a lower BMR (basal metabolic rate, BMR) [1158 ± 85 vs. 1231 ± 91 kcal/day, p = .011] and lower bone mineral content [2.15 ± 0.26 vs. 2.43 ± 0.31 kg, p = .009] than the normal group. Both LBMD and femoral neck BMD (Fn BMD) were positively correlated with BMI, BF%, LBM, and regional muscle/fat mass (all p < .05). There was also a positive correlation between LBMD and basal LH levels (p = .009) and waist-to-hip ratio (p = .034), whereas Fn BMD was positively correlated with TT levels (p = .029). Multiple linear regression analysis showed that LBM was positively associated with LBMD (β = .007, 95% confidence interval [CI] = 0.004-0.009, p < .001), while trunk muscle mass was positively associated with Fn BMD (β = .046, 95% CI = 0.013-0.080, p = .008). Fifteen percent of the patients with FHA exhibited low bone mass, a condition associated with prolonged weight loss. The basal LH and TT levels showed positive correlations with LBMD and Fn BMD, respectively. Meanwhile, BMR levels, BMI, BF%, and muscle mass were all positively correlated with LBMD and Fn BMD. Clinically, we should be attentive to suboptimal bone health in patients with FHA and take early screening, diagnosis and intervention measures, especially appropriate muscle mass gain, to prevent the onset of osteoporosis and fragility fractures in the long term.

The effect of acute hydration on body composition assessed by multi-frequency and single-frequency bioelectrical impedance.

Multi-frequency bioelectrical impedance (MF-BIA) provides an estimate of total body water. However, it is unknown if MF-BIA detects body water increases due to acute hydration, thus affecting the validity of MF-BIA body composition measurements. The purpose of this study was to compare the effects of pre-testing fluid ingestion on body composition estimation using single-frequency bioelectrical impedance (SF-BIA) and MF-BIA. Thirty-nine subjects (20 male, 19 female) were tested for body composition using DXA, SF-BIA and MF-BIA before and after consumption of 2 L of water. Hydration significantly increased fat percentage in men and women for MF-BIA (+2.1±0.7% for men, +2.6±0.7% for women) and SF-BIA (+1.3±0.7% for men, +2.1±0.9% for women). Additionally, hydration significantly increased fat-free mass (FFM) for DXA (+1.4±0.8 kg for men, +1.7±0.4 kg for women) and SF-BIA (+0.5±0.6 kg) in men. Hydration significantly increased fat mass (FM) for all modes (DXA +0.3±0.3 kg, MF-BIA +2.0±0.7 kg, SF-BIA +1.3±0.6 kg) in males, and only for MF-BIA (+2.2±0.3 kg) and SF-BIA (+1.7±0.5 kg) in females. Increases in FM were highest for MF-BIA for both males and females. Total body water was unchanged in males and significantly decreased with acute hydration in females. MF-BIA improperly categorizes increased mass due to acute hydration as fat mass, resulting in an increase in measured body fat percentage. These findings confirm the need to standardize hydration status for body composition measurements using MF-BIA.

Factors Associated with Cardiorespiratory Fitness in Breast Cancer Survivors from the State of Santa Catarina, Brazil: Cross-Sectional Study

Introduction: Oxygen consumption (VO2) is indicative of cardiorespiratory fitness (CRF) and lower levels are related to a higher risk of total mortality among individuals with cancer whose therapy can have adverse consequences on the cardiovascular system. Objective: To examine the associations of patient-reported sociodemographic, clinical, anthropometric outcomes and functional variables with CRF in 69 women (55±10 years) and to identify whether walking is a predictor of peak VO2 variation in this population with breast cancer (BC). Method: Female BC survivors receiving hormone therapy after two types of surgery (breast-conserving and mastectomy) underwent a CRF test on a cycle ergometer to measure peak VO2. A questionnaire containing sociodemographic, clinical data, patient reported outcomes (PROs) (depressive symptoms, sleep quality, fatigue, body image) and self-reported walking and tests to measure body fat percentage, waist circumference, flexibility and shoulder range of motion (RoM) were performed. Results: Unemployment and retirement were associated with low CRF, as was the use of aromatase inhibitors instead of tamoxifen. Depressive symptoms, worse body image, greater waist circumference, less flexibility and shoulder RoM were also associated with low CRF. Walking duration, controlled for age and body mass index (BMI), is a 13% predictor of peak VO2 variance in this sample. Conclusion: These factors must be considered in understanding the CRF profile of BC survivors. As walking was a predictor of peak VO2 variance, it should be recommended as a type of physical activity for patients with BC using hormone therapy.

Percentage Of Body Fat Related With Functional Capacity In Young Adults

Introduction. The percentage of body fat is a component of body composition in addition to bone mass, muscle mass, and body water content related to obesity. Diseases caused by an increase in body fat will have an impact on decreasing the body's functional capacity, disability, and death. Maximum Oxygen Volume (VO2 max) refers to the maximum amount of oxygen that humans can use during physical activity. It is usually used to test aerobic endurance or cardiovascular fitness so that VO2 max can describe a person's functional capacity. Percentage of body fat can affect VO2 max. Based on data from the Sports Development Index (SDI) in Indonesia, 43.9% of young adults have a poor VO2 max. This study aims to determine whether or not there is a relationship between body fat percentage and functional capacity in young adults. Methods. The study used a cross-sectional method and was followed by 92 respondents throughout October and November 2022. Bioelectrical Impedance Analysis (BIA) is used to measure body fat percentage. The 6-minute Walk Test is used to measure VO2 max. Results. The results of the study showed that the bivariate analysis of the Fisher's Exact test obtained a significant relationship between body fat percentage (measured by BIA) and body functional capacity (VO2 max) (p=0.028). Conclusion. There was a significant relationship between body fat percentage through BIA measurements and functional capacity in young adults.

Body mass index and body fat percentage in determining overweight and obesity among school going adolescents of urban Mysuru, Karnataka: a cross-sectional study

Background: Overweight and obesity among adolescents is an important global health issue. BMI is the commonly used screening tool but there can be under or over estimation. Body fat percentage estimation using bioelectrical impedance analysis is easy and non-invasive technique and along with BMI can provide a better predictive capacity. Considering importance of early detection of overweight and obesity in adolescents, present study was done among school going adolescents of urban Mysore. Objectives were to determine the prevalence of overweight and obesity using BMI and body fat percentage among school going adolescents and to determine the relationship between BMI and body fat percentage. Methods: A cross sectional study was conducted among 706 school students in urban Mysuru aged 13-16 years and semi-structured proforma was used to collect data. Anthropometric measurements taken and Omron HBF 701 Karada scan complete digital body composition monitor used to measure body fat percentage. BMI-for-age (5-19 years) WHO 2007 and McCarthy’s body fat reference used to classify participants. Statistical tests like Pearson’s correlation used. Results: According to BMI, 9.8% and 5% were overweight and obesity prevalence respectively and according to body fat percentage19.4% were over fat and 17.1% were obese. Among adolescents with normal BMI, 18.4% and 11.9% were classified as overfat and obese respectively according to body fat percentage. The correlation between BMI and body fat percentage was statistically significant. Conclusions: Higher prevalence of obesity seen according to body fat percentage cut-offs than according to BMI.

A STUDY OF BODY MASS INDEX (BMI) AND HEALTH STATUS OF ADOLESCENT GIRLS OF PATAN CITY

Dietary nutrients promote and maintain individual health. Puberty in girls is recognized as a special stage in her cycle of biological life that requires special attention in terms of nutrition and a balanced diet. Improper diet can lead to illness and malnutrition. India has high rates of malnutrition among her teenagers, according to data from the national nutrition monitoring service. Globally, an estimated 10% of children are overweight or obese, which poses health risks even into adulthood. Body mass index is a measure of weight based on a person's weight and height. It does not measure body fat percentage but is used to estimate a healthy weight based on a person's height, assuming average body composition. The researcher aimed to use BMI as a screening tool to check the health status of randomly selected 250 adolescent girls aged between 10-19 years of Patan city. Efforts were also made to analyze, predict and understand from these values future health-related problems in these subjects. Also, the researcher tried to check the role of diet on the value of BMI. From the below values, 53.6% (134/250) adolescent girls were found to be underweight, 36% (90/250) with normal nutritional status, &amp; 8% (20/250) were categorized as overweight. While only 2.4% (6/250) of the study subjects were labelled as obese. Also when an analyzed researcher found that diet has an impact on BMI values the percentage of healthier girls was more in the vegetarian group (83/250) compared to non-vegetarian girls (7/250) although the difference is very high. Also, it was striking to note that the number of overweight girls in the vegetarian group (20/250) was found to be more compared to overweight non-vegetarian girls. That researcher can conclude that BMI, Diet and health are closely related to each other.

GALNT2 rs4846914 SNP Is Associated with Obesity, Atherogenic Lipid Traits, and ANGPTL3 Plasma Level.

N-Acetylgalactosaminyltransferase 2 (GALNT2) is associated with serum lipid levels, insulin resistance, and adipogenesis. Additionally, angiopoietin-like (ANGPTL) proteins have emerged as regulators of lipoprotein lipase and lipid metabolism. In this study, we evaluated the association between GALNT2 rs4846914 variant, known for its association with lipid levels in European cohorts, with plasma levels of ANGPTL proteins, apolipoproteins, lipids, and obesity traits in individuals of Arab ethnicity. GALNT2 rs4846914 was genotyped in a cohort of 278 Arab individuals from Kuwait. Plasma levels of ANGPTL3 and ANGPTL8 were measured by ELISA and apolipoproteins by Luminex multiplexing assay. Allele-based association tests were performed with Bonferroni-corrected p-value thresholds. The GALNT2 rs4846914_G allele was associated with increased ANGPTL3 (p-values ≤ 0.05) but not with ANGPTL8 plasma levels. The allele was associated significantly with higher BMI and weight (p-values < 0.003), increased ApoC1 levels (p-values ≤ 0.006), and reduced HDL levels (p-values ≤ 0.05). Individuals carrying the GG genotype showed significantly decreased HDL and increased BMI, WC, ApoC1, and TG. Interactions exist between (AG+GG) genotypes and measures of percentage body fat, ApoA1A, ApoC1, and ApoB48-mediated HDL levels. GALNT2 is confirmed further as a potential link connecting lipid metabolism and obesity and has the potential to be a drug target for treating obesity and dyslipidemia.

478-P: GALNT2 Variant Associates with Increased ANGPTL3 Circulation Level and Obesity

Background: Polypeptide N-Acetylgalactosaminyltransferase 2 (GALNT2) gene has been associated with serum lipid levels, insulin resistance, and adipogenesis. One of its variants, rs4846914 has been shown to associate with Triglycerides and HDL levels in global genome-wide association studies. ANGPTL proteins have emerged as important regulators of lipid metabolism through its regulation of lipoprotein lipase activity. In this study we aimed to evaluate the association between GALNT2 variant with plasma level of ANGPTL3, 8 and apolipoproteins in individuals of Arab ethnicity. Methods: GALNT2 rs4846914 variant was genotyped in a cohort of 278 Arab individuals from Kuwait. Plasma levels of ANGPTL3 and 8 were measured by ELISA. Apolipoproteins were measured by Luminex multiplexing assay. Significance of association signals was assessed using Bonferroni-corrected P-values. Results: The GALNT2 rs4846914_G allele was associated with increased ANGPTL3 but not ANGPTL8 plasma levels. It was associated with obesity status with an odds ratio of 1.45 (CI:1.024-2.055) (P-value =0.036) . It also associated with increased levels of ApoC1 (P-values ≤0.006) and lower levels of HDL (P-values ≤0.05) . Levels of HDL were found to be mediated by interactions between genotypes (AG+GG) at rs4846914 and measures of percentage body fat (PBF) , apolipoproteins A1a, C1 and B48. Conclusions: Association between GALNT2 variant and lipid metabolism could be mediated through the increased ANGPTL3 protein level. Disclosure A.T.Thangavel: None. M.Abu-farha: None. P.Hebbar: None. M.G.Qaddoumi: None. F.Almulla: None. J.Abubaker: None.

초음파 측정기를 이용한 20대 남성 체지방률 추정식 개발

Purpose: The purpose of this study is to develop an equation for estimating body fat percentage for men in their twenties using an ultrasonic measuring device.<BR> Method: The percentage of body fat was measured on male students in their 20s in Gyeonggi-do. For the development of the estimation formula according to the internal cross-validity procedure, 105 subjects were divided into 70 in the estimation-type development group and 35 in the cross-validity test group. The regression formula development exploration and validity analysis were conducted.<BR> Results: As a result of the analysis, the coefficient of determination was 82% and the standard error was 3.2% in the estimation formula at the development stage. In cross-validity, the estimated body fat percentage did not differ from the measured body fat percentage (p=.660), and the coefficient of determination was 94% and the total error was 2.2%. The final estimation formula that synthesized all the research results was y=2.245+1.125x.<BR> Conclusion: In conclusion, the validity of the body fat ratio estimation formula developed based on the ultrasonic measuring device is verified. When this formula is applied to men in their 20s in Korea, it is confirmed that it is suitable for the individual together with the group.

Seasonal Changes in Midlife Women'S Percentage Body Fat: A 1-Year Cohort Study.

The purpose of this longitudinal, observational study was to examine whether age and seasonal changes in sedentary activity (sedAct), moderate-to-vigorous physical activity (MVPA), and energy intake (EI) predict changes in body composition among midlife women. We hypothesized that reductions in MVPA and increases in sedAct and EI in winter, along with greater baseline age would predict increases in percentage body fat (%BF) across seasons. This study used a longitudinal, within-subjects design. Setting: This study took place in Grand Forks, North Dakota. Participants included 52 midlife women (aged 40-60 years) who were observed over the course of one year. Percentage body fat measures were obtained via whole body Dual Energy X-ray absorptiometry. Participants were scanned once per season. We measured EI using the ASA24®. We used a GTX3 accelerometer to measure physical activity. Each season, participants wore the monitors for 7 days, 12 hours per day. All measures began in summer. Results of hierarchical multiple regression (MR) analyses showed that age increases (β = 0.310, p = 0.021) and summer-to-fall increases in EI (β = 0.427, p = 0.002) predicted seasonal increases in %BF (R2 = .36, F(5, 42)= 4.66, p = 0.02). Changes in MVPA and sedAct were not significant predictors. Repeated measures ANCOVA revealed that summer (M = 37.7263, 95% CI [35.8377, 39.6149]) to winter (M = 38.1463, 95% CI [36.1983, 40.0942]) increases in %BF are not reversed by spring (M = 37.8761, 95% CI [35.9365, 39.8157]). To minimize increases in %BF and maintain health, midlife women, particularly older women, should be encouraged to pay extra attention to their diet in the fall months.

Use of a Mobile Lifestyle Intervention App as an Early Intervention for Adolescents With Obesity: Single-Cohort Study.

BackgroundEffective, resource-efficient treatment is urgently needed to address the high rates of pediatric and adolescent obesity. This need has been accelerated by the COVID-19 pandemic. The use of a mobile health tool as an early intervention before a clinic-based multidisciplinary weight management program could be an effective treatment strategy that is appropriate during a pandemic.ObjectiveThis study aims to assess the effectiveness of and adolescent engagement with a mobile app–based lifestyle intervention program as an early intervention before enrollment in a clinic-based multidisciplinary weight management program.MethodsThis prospective single-cohort study involved adolescents, aged 10-16 years, who were overweight and obese (defined as BMI percentile above the 85th percentile). Participants used the mobile Kurbo app as an early intervention before enrolling in a clinic-based multidisciplinary weight management program. Kurbo’s health coaches provided weekly individual coaching informed by a model of supportive accountability via video chat, and participants self-monitored their health behavior. The implementation of Kurbo as an early intervention was evaluated using the reach, effectiveness, adoption, implementation, and maintenance framework by reach (number who consented to participate out of all patients approached), implementation (Kurbo engagement and evaluation), and effectiveness as measured by the primary outcome of the BMI z-score at 3 months. Secondary outcome measures included changes in body fat percentage, nutrition and physical activity levels, and quality of life at 3 months. Maintenance was defined as the outcome measures at 6-month follow-up.ResultsOf the 73 adolescents who were approached for enrollment, 40 (55%) of adolescents were recruited. The mean age was 13.8 (SD 1.7) years, and the mean BMI z-score was 2.07 (SD 0.30). In the multiethnic Asian sample, 83% (33/40) of the participants had household incomes below the national median. Kurbo engagement was high, with 83% (33/40) of participants completing at least 7 coaching sessions. In total, 78% (18/23) of participants rated the app as good to excellent and 70% (16/23) stated that they would recommend it to others. There were no statistically significant changes in BMI z-scores at 3 months (P=.19) or 6 months (P=.27). Participants showed statistically significant improvements in measured body fat percentage, self-reported quality of life, and self-reported caloric intake from the 3-day food diaries at 3 and 6 months.ConclusionsThe use of Kurbo before enrollment in an outpatient multidisciplinary clinical care intervention is a feasible strategy to expand the reach of adolescent obesity management services to a low-income and racially diverse population. Although there was no significant change in BMI z-scores, the use of Kurbo as an early intervention could help to improve quality of life and reduce body fat percentage and total caloric intake.

Established diet quality indices are not universally associated with body composition in young adult women.

To determine which established diet quality indices best predict weight-related outcomes in young women. In this cross-sectional analysis, we collected dietary information using the Harvard FFQ and measured body fat percentage (BF%) by dual-energy X-ray absorptiometry. We used FFQ data to derive five diet quality indices: Recommended Food Score (RFS), Healthy Eating Index 2015 (HEI-2015), Alternate Healthy Eating Index 2010 (AHEI-2010), alternate Mediterranean Diet Score (aMED) and Healthy Plant-Based Diet Index (HPDI). University of Massachusetts at Amherst. Two hundred sixty healthy women aged 18-30 years. The AHEI-2010 and HPDI were associated with BMI and BF%, such that a ten-point increase in either diet score was associated with a 1·2 percentage-point lower BF% and a 0·5 kg/m2 lower BMI (P < 0·05). Odds of excess body fat (i.e. BF% > 32 %) were 50 % lower for those in the highest v. lowest tertile of the AHEI-2010 (P = 0·04). Neither the RFS nor HEI-2015 was associated with BMI or BF%; the aMED was associated with BMI but not BF%. These results suggest that diet quality tends to be inversely associated with BMI and BF% in young women, but that this association is not observed for all diet quality indices. Diet indices may have limited utility in populations where the specific healthful foods and food groups emphasised by the index are not widely consumed. Future research should aim to replicate these findings in longitudinal studies that compare body composition changes over time across diet indices in young women.

Body fat percentage prediction in older adults: Agreement between anthropometric equations and DXA

It is difficult to measure body fat percentage in clinical settings. Equations using anthropometric measures are more feasible and can be used to estimate body fat. However, there is a need to analyze their accuracy in older adults. Our study aims to validate the use of anthropometric equations to estimate body fat percentage in older men and women. This study evaluated data from 127 Brazilian individuals aged between 60 and 91 years. Weight, height, skinfold thickness and waist and hip circumferences were measured. Seventeen anthropometric equations were tested using the crossed validity criteria suggested by Lohman and the graph analysis proposed by Bland and Altman and by Lin was also performed. The gold-standard method for comparing the anthropometric equations was the dual-energy absorptiometry X-ray (DXA). The average body fat percentage was 30.2±8.6% in men and 43.4±7.9% in women (p<0.001). In men, the equations which used skinfold thickness presented amplitude of 11.48%, while in women, amplitude's constant error (CE) was 22.88%. The equations based on circumferences and BMI presented CE variation from-5.3% to 29.68% on the estimation of body fat percentage, which means that a same male individual can have the total body adiposity diagnosed with 34.98% of variation, depending on the selection of the employed equation. For women this CE variation was 12.44%. Overall, all the equations yielded different results from the DXA. However, the best equations for male were the one of Lean etal. (1996), which uses the waist circumference, and for women the one of Deurenberg etal. (1991), developed from the body mass index. The need of developing specific equations for older adults still remains, since even the two best equations showed considerable limitations on predicating body fat percentage.

Objective aerobic fitness level and neuropsychological functioning in healthy adolescents and emerging adults: Unique sex effects

ObjectiveResearch suggests positive relationships between aerobic fitness and cognition in older adults; however, limited research has adequately investigated the relationship between objectively measured aerobic fitness and broad cognitive functioning in healthy adolescents and young adults without psychiatric or physical health disorders. Further, studies to date have disproportionately examined males and failed to examine sex differences. Here we examine the relationship between aerobic fitness and neuropsychological functioning in physically healthy youth and whether sex moderates these findings. DesignSixty-four healthy emerging adults (16-25 years-old; 32 female) underwent measurement of objective aerobic fitness (VO2 max) and neuropsychological assessment. Exclusion criteria included: left-handedness, prenatal medical issues or alcohol/illicit drug exposure, Axis-I psychiatric disorders, major medical disorders including metabolic conditions such as diabetes, hypertension, hyperlipidemia, major neurologic disorders, LOS greater than 2 min, intellectual disability or learning disability, regular substance use (e.g., greater than bi-weekly use of cannabis) or positive drug toxicology testing. MethodMultiple regressions examined VO2 max, sex, sex*VO2interaction in relation to neurocognition, controlling for objectively measured body fat percentage. ResultsPrior to including body fat percentage, higher VO2 max related to improved working memory (Letter-Number Sequencing; p = .03) and selective attention (CPT-II hit response time standard error; p = .03). Aerobic fitness significantly interacted with sex, as higher-fit males had better performance on two sustained attention tasks while females did not demonstrate this pattern (CPT-II variability standard error, p = .047; Ruff 2&7 Total Speed, p = .02). Body fat percentage was positively slower cognitive flexibility (D-KEFS color-word switching/inhibition, p = .046). ConclusionsVO2 independently predicted better working memory and selective attention. Increased aerobic fitness level related to increased performance on sustained attention tasks in males but not females. Therefore, aerobic fitness may be positively related to better cognitive functioning in physically healthy adolescents and emerging adults without metabolic conditions. Further research into factors (e.g., intensity or type of activity) that may relate to beneficial outcomes by sex are needed.

A 2\xa0year physical activity and dietary intervention attenuates the increase in insulin resistance in a general population of children: the PANIC study

Aims/hypothesisWe studied for the first time the long-term effects of a combined physical activity and dietary intervention on insulin resistance and fasting plasma glucose in a general population of predominantly normal-weight children.MethodsWe carried out a 2 year non-randomised controlled trial in a population sample of 504 children aged 6–9 years at baseline. The children were allocated to a combined physical activity and dietary intervention group (306 children at baseline, 261 children at 2-year follow-up) or a control group (198 children, 177 children) without blinding. We measured fasting insulin and fasting glucose, calculated HOMA-IR, assessed physical activity and sedentary time by combined heart rate and body movement monitoring, assessed dietary factors by a 4 day food record, used the Finnish Children Healthy Eating Index (FCHEI) as a measure of overall diet quality, and measured body fat percentage (BF%) and lean body mass by dual-energy x-ray absorptiometry. The intervention effects on insulin, glucose and HOMA-IR were analysed using the intention-to-treat principle and linear mixed-effects models after adjustment for sex, age at baseline, and pubertal status at baseline and 2 year follow-up. The measures of physical activity, sedentary time, diet and body composition at baseline and 2 year follow-up were entered one-by-one as covariates into the models to study whether changes in these variables might partly explain the observed intervention effects.ResultsCompared with the control group, fasting insulin increased 4.65 pmol/l less (absolute change +8.96 vs +13.61 pmol/l) and HOMA-IR increased 0.18 units less (+0.31 vs +0.49 units) over 2 years in the combined physical activity and dietary intervention group. The intervention effects on fasting insulin (regression coefficient β for intervention effect −0.33 [95% CI −0.62, −0.04], p = 0.026) and HOMA-IR (β for intervention effect −0.084 [95% CI −0.156, −0.012], p = 0.023) were statistically significant after adjustment for sex, age at baseline, and pubertal status at baseline and 2 year follow-up. The intervention had no effect on fasting glucose, BF% or lean body mass. Changes in total physical activity energy expenditure, light physical activity, moderate-to-vigorous physical activity, total sedentary time, the reported consumption of high-fat (≥60%) vegetable oil-based spreads, and FCHEI, but not a change in BF% or lean body mass, partly explained the intervention effects on fasting insulin and HOMA-IR.Conclusions/interpretationThe combined physical activity and dietary intervention attenuated the increase in insulin resistance over 2 years in a general population of predominantly normal-weight children. This beneficial effect was partly mediated by changes in physical activity, sedentary time and diet but not changes in body composition.Trial registrationClinicalTrials.gov NCT01803776Graphical abstract

Sex Affects The Difference In Body Fat Estimation Between Body Composition Devices

Commercially available upper-body (UB) and lower-body (LB) bioelectrical impedance analyzers (BIA) are commonly used to measure body fat percentage (%BF) and classify body composition status. Some evidence suggests that LB BIA underestimate %BF specifically in women. It is not clear if UB BIA devices also underestimate %BF in women or if LB and UB BIA devices underestimate %BF in men. PURPOSE: To compare %BF from air displacement plethysmography (ADP), UB BIA, LB BIA, and whole-body (WB) BIA and to determine if the %BF differences between devices are affected by sex. METHODS: 53 women (21±5 yrs) and 42 men (23±5 yrs) had their %BF measured via ADP, a hand-held UB BIA, a digital scale LB BIA, and a validated eight-electrode multifrequency WB BIA device following each device’s recommended procedures. Paired samples t-tests were used to compare %BF between devices within each sex. Independent samples t-tests were used to compare the %BF difference between devices for each sex. RESULTS: In women, UB (23.8±4.3%) and LB (20.4±5.8%) BIA yielded significantly (p<0.001) lower %BF than ADP (28.3±7.4%) and WB BIA (28.9±5.0%). In men, UB (15.6±5.3%) and LB BIA (15.0±4.0%) also yielded significantly lower %BF values than ADP (17.6±7.7%; p=0.012 vs. UB BIA; p=0.008 vs. LB BIA) and WB BIA (19.1±6.7%; p<0.001 vs. UB and LB BIA). The differences in %BF between devices were greater in women compared to men: WB - UB BIA difference 5.0±2.6 vs. 3.6±3.3%, p=0.021 (women vs. men); WB - LB BIA difference 8.5±4.1 vs. 4.2±5.1%, p<0.001; ADP - UB BIA difference 4.5±5.9 vs 2.0±5.0%, p=0.028; ADP - LB BIA difference 7.9±6.3 vs. 2.7±6.2%, p<0.001; UB -LB BIA difference 3.4±3.5 vs. 0.7±3.2%, p<0.001. CONCLUSIONS: These results suggest that commercially available UB and LB BIA devices systematically underestimate %BF in both men and women compared to a validated multifrequency WB BIA and ADP. The degree of underestimation in %BF for commercially available BIA devices is greater in women compared to men. Use of these commercially available BIA devices may cause misclassification of body composition status, especially in women.

Factors affecting cord blood leptin levels in a consecutive birth cohort

Introduction The fetus that fails to meet its ideal growth trajectory has increased risks of poor health outcomes throughout life. “Gold standard” methods of anthropometric assessment such as measurement of percentage body fat can be difficult to apply across populations and other biomarkers such as serum concentration of umbilical cord blood leptin may be more effective for screening. This study reports cord blood leptin levels in a large prospective consecutive birth cohort and assesses the relationship between leptin and neonatal and maternal factors. Methods Venous umbilical cord blood samples were collected from a prospective consecutive cohort of pregnancies at the time of delivery. Maternal and neonatal characteristics and details of delivery were collated. Serum leptin levels were measured, associations with demographic features were identified, and a normal range was established. The association between cord leptin level and neonatal outcome was tested. Results Umbilical cord leptin and maternal and neonatal characteristics were collected at 1275 births. The median leptin value was 10.8 ng/ml (IQR: 6.4, 17.8 ng/ml). Log10 leptin was significantly associated with gestation at delivery, birthweight (BWt), infant sex, plurality, and maternal body mass index (BMI) (p < .001). Observed leptin values were expressed as multiples of the median (MoM). The mean leptin MoM was significantly lower in infants admitted to NICU following delivery (0.85; 95% confidence interval [CI]: 0.78–0.91 versus 1.05; 95% CI: 1.03–1.06 (controls), p < .001). There was no significant association between leptin MoM values and 5-min Apgar scores. Conclusions Neonatal cord leptin levels are influenced by a number of maternal and fetal characteristics. Absolute levels can be adjusted to account for normal population variation. Infants requiring admission to NICU have lower mean leptin MoM levels. Further studies are needed to see whether the identification of fetuses with polarized leptin levels (<5th or >95th centile) will benefit from further surveillance or intervention in infancy.

Fracture risk factors among children living in New Zealand

Factures are common during childhood. There are limited data available regarding relationships between bone fracture history and calcium intake, sugar sweetened beverages (SSBs) intake, vitamin D status, physical activity (PA), ethnicity, and body composition in New Zealand (NZ) children. Identifying groups of NZ children at risk of fracture and associated predictors may help to improve bone quality during childhood and decrease the risk of fractures throughout life. The aim of this study was to investigate fracture history and associated risk factors in New Zealand children. Children aged 8–12 years were recruited. Capillary blood spots collected from a finger prick were as analyzed for 25(OH)D concentrations. Bioelectrical impedance analysis (InBody720, Seoul, Korea) was used to measure body fat percentage (%BF). Information about fracture history, siblings’ history of fractures, family osteoporosis history, PA, ethnicity, and intake of calcium containing foods, and SSBs was collected using questionnaires. Children (n = 647, 354 girls), mean ± SD age 9.8 ± 0.7 years were recruited from six Auckland primary schools. NZ European (n = 252) (NZE) and South Asian (n = 68) children reported the lowest (20.2 %) and highest (44.1 %) fracture incidence, respectively. NZE compared to South Asian children, had higher 25(OH)D concentrations (74.6 ± 19.8 vs. 48.4 ± 19.3 nmol/L, P < 0.001), higher total calcium intake (764.0 ± 394.4 vs. 592.7 ± 266.3 mg/d, P < 0.018), and lower %BF (19.5 ± 6.6 vs. 23.4 ± 8.4, P < 0.003). Māori children had the next highest fracture rate (32.5 %). This group had adequate 25(OH)D (64.2 ± 18.9 nmol/L), but high %BF (23.9 %) and most participated in vigorous PA. After stratifying by sex, binary logistic regression analysis revealed the main determinants of fracture history for boys were high %BF, low 25(OH)D, low calcium intake, high SSBs consumption, siblings’ fracture history, family osteoporosis history, and being South Asian; and in girls, high SSBs consumption, siblings’ fracture history, and family osteoporosis history. We found South Asian ethnicity was a significant risk factor for boys. Some children were at high risk of vitamin D deficiency and for whom supplementation may be necessary in winter. Good nutrition (especially good sources of calcium and reducing SSBs intakes) should be recommended to children during growth and development to reduce their risk of fractures.