Obesity In Chinese Adolescents Research Articles

Short-term lifestyle education on obesity reduction in adolescents.

Obesity is increasing in adolescents in China. However, the awareness of obesity and prevention on related risk factors were not well known. We aim to assess the effectiveness of short-term health education intervention on obesity in Chinese adolescents. In this study, 42 primary and secondary schools from Qingdao were randomly divided into the education and control groups. A total of 11,739 adolescents was included in the current study. The logistic regression was employed to assess odds ratio (OR) of education intervention on overweight and obesity prevalence adjusting for covariates. The baseline prevalence of overweight and obesity was significantly higher in urban than in rural areas and in boys than in girls. After 1 year lifestyle intervention, the proportion of students with awareness of obesity was higher, meanwhile age-adjusted mean values of weight, body mass index, duration of watching TV and doing homework were lower in education group than control group. The corresponding figures were 43.6 [95% CI (confidence intervals); 43.3-43.9] kg versus 44.3 (95% CI; 44.0-44.6) kg, 18.6 (95% CI; 18.5-18.7) kg/m2 versus 18.9 (95% CI; 18.8-19.1) kg/m2, 1.3 (95% CI; 1.2-1.3) hours/d versus 1.4 (95% CI; 1.3-1.4) hours/d, and 1.5 (95% CI; 1.4-1.5) hours/d versus 1.8 (95% CI, 1.7-1.8) hours/d. The multivariable adjusted OR for combined prevalence of overweight and obesity was 0.85 (95% CI, 0.76-0.96) in education group as compared with control group. Short-term health education intervention results in significantly higher reductions in obesity parameters and improvement in awareness in Chinese adolescents.

Sleep-Body Composition Relationship: Roles of Sleep Behaviors in General and Abdominal Obesity in Chinese Adolescents Aged 17-22 Years.

This study aimed to investigate the association between sleep behaviors and body composition, which was measured by bioelectrical impedance analysis (BIA) among Chinese adolescents. Overall, 444 students (65.3% females, 19.12 ± 1.177 years) completed questionnaires describing sleep characteristics. Sleep characteristics were derived from subjective means. Body composition was obtained from BIA by InBody 720 (Biospace Co. Ltd., Seoul, Republic of Korea). Regression models tested relationships between sleep and body composition after adjustment for covariates. Students with weekday nap duration (>30 min/d) exerted higher waist-height ratio (WHtR) (B = 0.013, FDR-corrected p = 0.080). Average sleep duration (≤7 h/d) was linked to more WHtR (B = 0.016, FDR-corrected p = 0.080). People with high social jetlag showed gained visceral fat area (B = 7.475), WHtR (B = 0.015), waist to hip ratio (B = 0.012), fat mass index (B = 0.663) and body fat percentage (B = 1.703) (all FDR-corrected p < 0.1). Individuals with screen time before sleep (>0.5 h) exhibited higher visceral fat area (B = 7.934, FDR-corrected p = 0.064), WHtR (B = 0.017, FDR-corrected p = 0.080), waist to hip ratio (B = 0.016, FDR-corrected p = 0.090), fat mass index (B = 0.902, FDR-corrected p = 0.069) and body fat percentage (B = 2.892, FDR-corrected p = 0.018). We found poor sleep characteristics were closely related to general and abdominal obesity.

Metabolome Profiling and Pathway Analysis in Metabolically Healthy and Unhealthy Obesity among Chinese Adolescents Aged 11-18 Years.

The underlying mechanisms of the development of unhealthy metabolic phenotypes in obese children and adolescents remain unclear. We aimed to screen the metabolomes of individuals with the unhealthy obesity phenotype and identify the potential metabolic pathways that could regulate various metabolic profiles of obesity in Chinese adolescents. A total of 127 adolescents aged 11-18 years old from China were investigated using a cross-sectional study. The participants were classified as having metabolically healthy obesity (MHO) or metabolically unhealthy obesity (MUO) based on the presence/absence of metabolic abnormalities defined by metabolic syndrome (MetS) and body mass index (BMI). Serum-based metabolomic profiling using gas chromatography-mass spectrometry (GC-MS) was undertaken on 67 MHO and 60 MUO individuals. ROC analyses showed that palmitic acid, stearic acid, and phosphate could predict MUO, and that glycolic acid, alanine, 3-hydroxypropionic acid, and 2-hydroxypentanoic acid could predict MHO (all p < 0.05) from selected samples. Five metabolites predicted MUO, 12 metabolites predicted MHO in boys, and only two metabolites predicted MUO in girls. Moreover, several metabolic pathways may be relevant in distinguishing the MHO and MUO groups, including the fatty acid biosynthesis, fatty acid elongation in mitochondria, propanoate metabolism, glyoxylate and dicarboxylate metabolism, and fatty acid metabolism pathways. Similar results were observed for boys except for phenylalanine, tyrosine and tryptophan biosynthesis, which had a high impact [0.098]. The identified metabolites and pathways could be efficacious for investigating the underlying mechanisms of the development of different metabolic phenotypes in obese Chinese adolescents.

Retracted: Analyzing Neck Circumference as a Tool for Evaluating Overweight and Obesity in Chinese Adolescents.

[This retracts the article DOI: 10.1155/2021/1274627.].

Associations of Social Jetlag with Dietary Behavior, Physical Activity and Obesity among Chinese Adolescents.

This study aimed to investigate the associations between social jetlag (SJL), dietary behavior, physical activity, and weight status in Chinese youth. Data were derived from a cross-sectional survey in Wuhan, China in 2019. Information on SJL, the frequency of food and beverage consumption, physical activity, and BMI category were collected via a self-reported questionnaire. The Kruskal-Wallis test and ANOVA were conducted to determine differences in daily consumption frequency of food and beverage groups, BMI category, and physical activity among SJL groups. Logistic regressions and restricted cubic splines were performed to test the association between SJL and the incidence of overweight or obesity. A final sample of 3567 Chinese adolescents [mean (SD) age, 14.67 (1.72) years; 47.41% (1691) female] were included. Our findings demonstrated that adolescents with SJL may consume more unhealthy foods and fewer beneficial foods, while engaging in less moderate to vigorous physical activity (MVPA) and reporting higher BMIs. In addition, adolescents who experience more than 2 h of SJL had significant greater risk of overweight or obesity. Our findings on SJL of Chinese adolescents confirm the harmful effects of SJL and also provide insights into the etiology of obesity in Chinese adolescents.

Analyzing Neck Circumference as a Tool for Evaluating Overweight and Obesity in Chinese Adolescents.

Overweight and obesity at an early age are important criteria for predicting chronic diseases. Each anthropometric method available to assess obesity has its limitations. Recently, neck circumference (NC) has received greater attention as a new evaluation index. This study aimed to investigate the relationship between NC and overweight in Chinese Yi adolescents. A total of 647 Chinese Yi male and female students, aged 13–18 years, were randomly selected from a junior high school and a senior middle school in Leshan, Sichuan Province of China. The measurement indexes included height, weight, waist circumference (WC), and NC, and clinical information was collected by trained physicians. The neck cutoff values were determined through the receiver operating characteristic (ROC) curve and the area under the curve (AUC). The correlation among NC, body mass index (BMI), and WC was determined by Pearson's correlation coefficient. The ROC analysis revealed that the AUC values were 0.79–0.95 for boys and 0.83–0.91 for girls. The correlation among NC, BMI, and WC in obese boys and girls was higher than 0.70 in both genders. In addition, the NC cutoff values of high BMI ranged from 31.0 cm to 36.1 cm for boys and 31.2 cm to 34.5 cm for girls, respectively. There was a significant positive correlation between NC and obesity in Chinese Yi adolescents. The NC can be used as an additional index to predict the obesity of Chinese Yi adolescents.

The Association Between Single-Child Status and Risk of Abdominal Obesity: Result From a Cross-Sectional Study of China.

Background: Obesity has become a serious problem threatening the health of children and adolescents, and China's one-child policy has affected family structure and parenting practice, which may result in several adverse health outcomes. The present study aims to investigate the association between single-child status and the risk of abdominal obesity in Chinese adolescents and also to compare the differences in the risk of unideal energy-related behaviors.Methods: Data were obtained from a school-based cross-sectional survey conducted in seven provinces of China, in 2012. A total of 31,291 students aged 7–17 years were recruited in this study. Anthropometric measurements were conducted to assess height and waist circumference, and questionnaires were used to obtain information of single-child status, parental educational attainment, parental weight status, and offspring energy-related behaviors. Multivariate logistic regression models were used to estimate the odds ratio (OR) and 95% confidence intervals (95% CI) of single-child status and odds of childhood abdominal obesity and energy-related behaviors.Results: The prevalence of abdominal obesity was 18.2% in single children, which was higher than that of non-single children (13.7%). The prevalence was also higher in single children in different sex and residence subgroups. Logistic regression models showed that single children had 1.33 times (OR: 1.33, 95% CI: 1.24–1.43, P < 0.001) higher odds of abdominal obesity compared to non-single children. Single children had 1.08 times higher odds of physical inactivity (OR: 1.08, 95% CI: 1.03–1.14, P = 0.004), 1.13 times higher odds of excessive sugar-sweetened beverages (SSBs) consumption (OR: 1.13, 95% CI: 1.05–1.23, P = 0.002), and 1.08 times more likely to eat out (OR: 1.08, 95% CI: 1.02–1.13, P = 0.006). Those associations were more remarkable in single girls.Conclusion: Being a single child may be associated with a higher odds of childhood abdominal obesity and unhealthy energy-related behaviors. Future interventions and strategies to prevent abdominal obesity should focus on this high-risk population.

Serum galectin-3BP as a novel marker of obesity and metabolic syndrome in Chinese adolescents

IntroductionChildhood obesity (OB) and metabolic syndrome (MetS) have become a worldwide health problem. Comparative proteomic approaches are widely used in human OB to analyze protein changes in blood plasma. The...

Lipidomic Profile Revealed the Association of Plasma Lysophosphatidylcholines with Adolescent Obesity.

Objective The human lipidomic profile reflects lipid metabolism, including the early phase of pathophysiological changes associated with diseases. An investigation of the association between the plasma lipidomic profile and adolescent obesity might provide new insights into the biological mechanisms of obesity. Therefore, we aimed to investigate the association of the plasma lipidome with obesity in Chinese adolescents using lipidomics. Methods Using a combination of liquid chromatography and electrospray ionization tandem mass spectrometry, we quantified 328 lipid species from 24 lipid classes and subclasses in 100 male adolescents aged 14–16 years who were categorized into four groups: (1) normal weight with traditional normal clinical plasma lipid levels (NN); (2) normal weight with traditional abnormal clinical plasma lipid levels (NA); (3) obese with traditional normal clinical plasma lipid levels (ON); and (4) obese with traditional abnormal clinical plasma lipid levels (OA). The concentrations of all the lipid species were compared between obese and normal-weight adolescents at different traditional clinical plasma lipid levels using the Kruskal–Wallis test followed by the Mann–Whitney U test. A partial least squares discriminant analysis (PLS-DA) was applied to select lipids with a significant ability to discriminate adolescent obesity. Results The lipidomic profile distinguished obese adolescents from normal-weight subjects. Regardless of whether traditional clinical plasma lipid levels were normal or abnormal, we observed a significant reduction in the levels of five lysophosphatidylcholines (LPC) species (LPC18:2, LPC18:1, LPC20:2, LPC20:1, and LPC20:0) in the obese group compared with the normal-weight group (difference = −31.29% to −13.19%; P=9.91 × 10−5 to 2.28 × 10−2). The ability of these five LPC species to discriminate adolescent obesity was confirmed in the PLS-DA model. Conclusions The findings provided evidence for the association of some LPC species with adolescent obesity. The discriminatory effects of five LPC species were identified between normal-weight and obese adolescents, independent of traditional clinical plasma lipid levels. These results will provide a basis for validation in subsequent studies.

Dietary pattern is associated with obesity in Chinese children and adolescents: data from China Health and Nutrition Survey (CHNS)

BackgroundAssociations of dietary patterns in Chinese adolescents and children with later obesity have not previously been investigated. The purpose of the present study was to evaluate the associations between dietary patterns and the risk of obesity in Chinese adolescents and children by using a longitudinal design.MethodsData from the China Health and Nutrition Survey (CHNS), a nationally representative survey, were used for our analysis. 489 participants 6–14 years of age were followed from 2006 to 2011. Factor analysis was used to identify the dietary patterns in Chinese adolescents and children. Ordered logistic regression models were used to examine the association between dietary patterns and later obesity.ResultsTwo dietary patterns were revealed by factor analysis, the traditional Chinese dietary pattern (with high intake of rice, vegetables, poultry, pork and fish and the modern dietary pattern (with high intake of wheat, processed meat and fast food). Children in the highest quartile and the second-highest quartile of the traditional Chinese dietary pattern was inversely associated with later obesity compared with children in the lowest quartile over 5 years (OR = 0.19, 95%CI: 0.09, 0.40 for Q4; OR = 0.47, 95%CI: 0.33, 0.67 for Q3); Children in the highest quartile of the modern dietary pattern was positively associated with later obesity compared with children in the lowest quartile over 5 years (OR = 2.02, 95%CI: 1.17, 3.48).ConclusionsDietary patterns in Chinese adolescents and children are associated with later obesity. These findings further confirm the importance of children’s dietary patterns in later obesity and lay groundwork for dietary culture-specific interventions targeted at reducing rates of obesity in children and adolescents.

Dietitian-led lifestyle modification programme for obese Chinese adolescents with non-alcoholic fatty liver disease: a randomized controlled study.

The prevalence of non-alcoholic fatty liver disease (NAFLD) in children is increasing. This study evaluated the efficacy of a dietitian-led lifestyle modification programme (D-LMP) to reduce NAFLD in obese adolescents. Subjects with intra-hepatic triglyceride content (IHTC) equal to or greater than 5% diagnosed by proton-magnetic resonance spectroscopy (1H-MRS) were enroled and randomly assigned to either the D-LMP intervention or conventional paediatrician-led consultation (P-CON) group. Subjects in the P-CON group received usual care consisting of a consultation by a paediatrician with the child and parents every 16 weeks. Intention-to-treat analysis was used for data analysis. Fifty-two subjects were recruited, with 26 in each group. After the initiation phase (at week-16), there was a greater difference in the change in the IHTC and BMI z-score in the D-LMP group (P = 0.029 and <0.001, respectively) and there was a decrease in dietary intake of fat content (P = 0.019). After 52 weeks of the maintenance phase, both groups had reductions of IHTC to 2-3% and there was no intergroup difference in the rate of reduction. During the maintenance phase, parents' involvement was minimal in the D-LMP group, with only three parents accompanying their children to attend the dietitian sessions. In contrast, over 90% of the parents in the P-CON group regularly accompanied their children to attend the consultations suggesting the possibility that regular parental and paediatrician involvement may contribute to increasing awareness on fatty liver complications. Multivariate analysis showed that only reduction in body fat remained as an independent factor associated with remission of NAFLD at the end of both study phases. A dietitian-led lifestyle modification intervention reduced IHTC, BMI z-score and body fat in obese Chinese adolescents with NAFLD. To sustain the effect of this intervention, regular parental and paediatrician involvement may be important.

Prevalence and characteristics of overweight and obesity among Chinese youth aged 12–18 years: a multistage nationwide survey

ObjectiveThe aims of the current study were to assess the prevalence of overweight and obesity by four different references and to explore the characteristics of adolescent overweight and obesity in Chinese secondary school students aged 12–18 years. Study designA cross-sectional study was conducted in this study. MethodsUsing stratified random cluster sampling, 8999 secondary school students were enrolled. The references developed by Must and Dallal and Dietz, the Childhood Obesity Working Group of the International Obesity Task Force, the US Centers for Disease Control and Prevention, and the Group of China Obesity Task Force (GCOTF reference) were used to identify overweight and obese students. ResultsThe prevalence of adolescent overweight and obesity vary substantially based on the four references. The prevalence of adolescent overweight and obesity based on GCOTF reference are 8.4% and 4.1%, respectively, which is significantly lower than the prevalence of overweight and obesity in their peers in 2000 (χ2 = 24.03, P < 0.01). The prevalence of overweight and obesity in boys are 12.0% and 5.7%, which are higher than those in girls, 4.6% and 5.7% (χ2 = 240.68, P < 0.01). The prevalence of overweight and obesity in singletons are higher than those in non-singletons (χ2 = 40.25, P < 0.01). The prevalence of overweight and obesity in students with lower school community ladder of subjective social status are higher than those from higher ones (χ2 = 21.61, P < 0.01). ConclusionThe GCOTF reference is more suitable for screening overweight and obesity in Chinese adolescents. The current prevalence rates of adolescent overweight and obesity decreased, and girls made a tremendous contribution to this decreasing trend. Singletons and adolescents in lower school community ladder of subjective socio-economic status may be at higher risk of getting overweight and obesity. More effective strategies with full consideration to the characteristics above should be developed to control and prevent adolescent overweight and obesity.

RETRACTED: Association between peroxisome proliferator-activated receptor, UCP3 and lipoprotein lipase gene polymorphisms and obesity in Chinese adolescents

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). Please note that this retraction notice has been updated in September 2021, as follows: This article has been retracted at the request of the Editors in Chief due to concerns regarding the authorship. Certain individuals were erroneously indicated as co-authors of the article when it was originally published. These individuals have informed the journal that they did not contribute to the article and that they had no knowledge of its submission for publication. We confirm, following investigation, that those individuals previously identified by the submitting author as co-authors did not author, approve or submit this article for publication, and the previous attribution of the article to them was in error. We have not had a response from Dr Mao and Dr Cai regarding authorship. As a result of the correspondence with Associate Professor Z. Zou and Dr L. Wang, we believe that the paper needs to be retracted and have elected to proceed with retraction.

Variants of 11β-hydroxysteroid dehydrogenase (HSD11B) gene type 1 and 2 in Chinese obese adolescents.

To investigate the relationship between 11β-hydroxysteroid dehydrogenase (HSD11B) gene type 1 and 2 and obesity in Chinese children. A total of 400 obese and 200 healthy adolescents were enrolled as obese and control groups. Seven SNPs in HSD11B1 (rs4393158, rs2235543, rs10082248, rs10863782, rs2236903, rs2298930, rs4545339) and four variants in HSD11B2 gene (rs28934592, rs28934591, rs28934594 and rs28934593) were measured by automated platform MassArray. The rs28934592 in HSD11B2 and rs10863782 in HSD11B1 were excluded as false positive or HWE P < 0.05. Moreover, one allele type was found in the other three locations of HSD11B2. The minor allele frequency of rs2235543 and rs10082248 was higher in patients than that in controls (P = 0.045, P = 0.041, respectively). The rs10082248, rs2298930 and rs4545339 were associated with the risk of obesity in the recessive model (P < 0.05, respectively). Moreover, the total cholesterol in patients with GG or AG genotype was significantly higher than that in patients with AA genotype in rs10082248. The rs4393158 was associated with the hypertension in log-additive model test (P = 0.037), and glucose abnormal and hypercholesteremia in dominant model test (P < 0.05, respectively), while the rs2235543 was associated with hypercholesteremia in overdominant model test (P = 0.017). The polymorphism of HSD11B1 may be a cause of childhood obesity, or even associated with the complication of childhood obesity. However, variants of HSD11B2 may be not a cause of obesity.

Variants of 11β-hydroxysteroid dehydrogenase (HSD11B) gene type 1 and 2 in Chinese obese adolescents

Variants of 11β-hydroxysteroid dehydrogenase (HSD11B) gene type 1 and 2 in Chinese obese adolescents

Platelet activity in Chinese obese adolescents with and without insulin resistance

To investigate the platelet activity in Chinese obese adolescents with and without insulin resistance. A cross-sectional study was performed in 159 obese Chinese adolescents to investigate their platelet activity using anthropometrics and biochemical parameters, oral glucose tolerance test and platelet testing. An index of insulin sensitivity, homeostasis model assessment of insulin resistance (HOMA-IR), and plasma fibrinogen, prothrombin fragment 1.2 (PT 1.2), fibrinopeptide A (FPA) and the levels of aggregation to collagen 1μg/ml, adenosine diphosphate (ADP) 10μmol/L and arachidonic acid (AA) 0.5mmol/L were measured. Obese adolescents with insulin resistance had significantly higher HOMA-IR, glucose response curve (AUC), insulin AUC, PT 1.2, FPA and fibrinogen and aggregation (to collagen 1μg/ml, ADP 10μmol/L and AA 0.5mmol/L) comparison with obese adolescents without insulin resistance (P<0.05). Moreover, a positive correlation was found between both aggregation (to collagen, ADP and AA) and HOMA-IR (ρ=0.716; P<0.01, ρ=0.682; P<0.01 and ρ=0.699; P<0.01, respectively), glucose AUC (ρ=0.479; P<0.01, ρ=0.416; P<0.01 and ρ=0.458; P<0.01, respectively) and insulin AUC (ρ=0.585; P<0.01, ρ=0.511; P<0.01 and ρ=0.576; P<0.01, respectively) in obese adolescents with insulin resistance. Insulin resistance is a major determinant of platelet activation in Chinese obese adolescents.

Study on waist circumference and hip circumference of 7 - 18 year-old children and adolescents in Shandong province

To study the development of waist circumference (WC) and hip circumference (HC) in children and adolescents in Shandong province, and to provide scientific data for developing related reference values for screening central obesity in Chinese children and adolescents. Using data from 'Student physical fitness and health surveillance 2010 project' in Shandong province, a total of 42 275 students aged 7 - 18 years were selected to participate in this study. WC, HC, waist-to-hip ratio (WHR) and wrist-to-stature ratio (WSR) of subjects were measured. Comparison of data from the current study and other similar studies was made. The mean values of WC increased with age, and boys all significantly higher than girls in all age categories (P < 0.01). There were two crosses on gender regarding the HC curves: before the age of 11 years, with mean HC higher in boys than in girls, but girls were higher than boys between the age of 12 to 14 while boys were also higher than girls after the age of 15 years. The 50(th) percentiles (P(50)) of WC of children and adolescents aged 7 to 18 years in Shandong appeared above the figures by 1.3 - 3.1 cm (boys) and 1.2 - 2.0 cm (girls) from 15 provinces in China as well as above the data from Hong Kong by 1.9 - 5.4 cm (boys) and 2.0 - 6.5 cm (girls), respectively. Overall, 20.20% of the boys and 16.57% of the girls had a WC of ≥ 90(th) percentile and 15.73% and 7.38% of the boys and girls had a WHtR of ≥ 0.5 which both showed significant differences between genders (P < 0.01). Children and adolescents from Shandong province had a high level of WC.

Body mass index cut-offs for overweight and obesity in Chinese children and adolescents aged 2 - 18 years

To study the body cut-offs of mass index (BMI) for the purpose of screening overweight and obesity for Chinese children and adolescents aged 2 - 18 years. Based on the BMI growth reference values for Chinese children aged 0 - 18, using the common methods to establish the BMI cut-offs for screening overweight and obesity. These methods were having the same empirical percentile or Z scores and the BMI value at 18 years consistent with adults. Three sets of BMI cut-offs, including (BMI₂₄, BMI₂₈), (P₈₅, P₉₅) and (Z₁, Z₂), were initially identified. Differences were compared on different cut-off points and prevalence rates of overweight and obesity with different BMI reference, different values and "prevalence" of overweight and obesity based on "2004 Beijing Child and Adolescent Metabolic Syndrome Study". Cut-offs standards which recommended by the Chinese Working Group on Obesity for Children (WGOC) and by the International Obesity Task Force (IOTF) were also used. Finally the appropriate cut-offs were defined. Three sets of BMI cut-offs for screening overweight and obesity for Chinese children and adolescents aged 2 - 18 years were obtained according to the above mentioned methods for selection. The prevalence rates of overweight and obesity defined by those cut-offs appeared not to be significantly different. Compared with the WGOC, the BMI cut-off points for screening overweight and obesity for both boys and girls from our study were very close to the WGOC', but cut-off points for screening overweight for girls aged 8.5 - 15.5 y was 0.3 - 1.0 kg/m² lower than the WGOC'. Going through the database on screening of "2004 Beijing Children's Metabolic Syndrome Survey", the prevalence of overweight for girls was about 3.4% higher than using the cut-offs of WGOC. Results from this study suggested that the BMI cut-offs passed through the cut-off point of BMI₂₄ and BMI₂₈ at 18 years was appropriate for screening overweight and obesity in Chinese children from 2 to 18 years, and achieved the continuity in age and consistency in screening standard when using the BMI indicator in children and adolescents.

Effects of Short-Term Resistance Training on Serum Leptin Levels in Obese Adolescents

The purpose of this study was to examine the effects of a short-term resistance training program on serum leptin concentrations in obese adolescents. Eighteen Chinese obese adolescents participated in the supervised weight management program. Resistance training was conducted three times a week on alternate days for 6 weeks. Body composition [body fat mass (FM) and body lean mass (LM)] determined by dual-energy X-ray absorptiometry, muscle strength and leptin, insulin and glucose were measured before and after training. Subjects demonstrated significantly improved strength of leg, chest and bicep under conditions of stability in weight, FM and LM. There were positive correlations between leptin and body mass index, FM, %FM, waist girth and hip girth, and negative correlations between leptin and %L M at the resting state before and after 6 weeks of resistance training. No significant relationship was found between leptin concentration and the parameters of muscular strength or concentrations of insulin and glucose. Compared to pre-training values, serum leptin levels were not significantly altered, while relative leptin (leptin/FM) decreased significantly after the short-term resistance training. These results indicate that short-term resistance training enhances muscle strength but does not alter leptin levels in obese adolescents with weight and FM stability. The results also suggest that 6 weeks of resistance training decreases the requirement of leptin per unit of FM and improves leptin sensitivity in obese adolescents.

An Evaluation of a Weight-Loss Program Incorporating E-Learning for Obese Junior High School Students

Obesity in adolescents is continuing to rise at an alarming rate and is becoming an important public health problem in Taiwan. Therefore, the aims of this study were (1) to evaluate the effectiveness of a Weight-loss E-learning Program (WEP) on obese Chinese adolescents and (2) to gauge this group's satisfaction with the WEP. The design was quasi-experimental, using purposive samples from two junior high schools in Taipei, Taiwan. Obese adolescents between 12 and 14 years of age with body mass indexes (BMI) over 25 kg/m2 were recruited. A 14-week WEP was developed to expedite weight loss for the selected adolescents. Data such as BMI, waist-to-hip ratio, waist circumference, hip circumference, mid-arm circumference, triceps skinfold, blood pressure, and physical fitness were collected through standardized instruments and methods before and after the WEP. The satisfaction of the subjects and four psychosocial variables were evaluated and taken into account by authoritative scales and questionnaires. In total, 37 adolescents participated in this study. After the WEP, we found significant decreases in BMI (p < 0.05), waist circumference (p < 0.05), and triceps skinfold (p < 0.001) in the sample population. Improvements were found in three of four tests of physical fitness (p < 0.001, p < 0.05, and p < 0.01, respectively). All psychosocial variables showed significant favorable changes (p < 0.01 for self-esteem scores, p < 0.001 for the other three variables) and satisfaction levels for the WEP ranged from 56.6% to 83.8% in four different criteria. The WEP was effective in helping obese Chinese adolescents lose weight. However, there is still room for improvement.