Weight‐Bearing Physical Activity among Girls and Mothers: Relationships to Girls’ Weight Status

Objective: To assess weight‐bearing physical activity (WBPA) barriers, benefits, self‐efficacy, social influence, and behaviors [WBPA and physical activity (PA)] among girls and their mothers according to girls’ weight status (nonoverweight vs. overweight). Research Methods and Procedures: Participants were 9‐ to 11‐year‐old girls (n = 295) and their mothers who participated in the baseline assessment of a nutrition and PA intervention trial. Girls’ and mothers’ WBPA attitudes and mothers’ WBPA behaviors were self‐reported on questionnaires. Girls’ WBPA and total PA behaviors were self‐reported using a structured interview (Physical Activity Checklist Interview). Stature and weight were measured by standardized anthropometrics. Overweight status was based on BMI. Results: Compared with nonoverweight girls, overweight girls were significantly more likely to report barriers to WBPA participation and perceive social influence from family and friends to do more WBPA. They were also significantly less likely to report self‐efficacy regarding WBPA and to believe that they did enough WBPA. Compared with mothers of nonoverweight girls, mothers of overweight girls were significantly more likely to report that it is difficult to persuade their daughters to do more WBPA and significantly less likely to report that WBPA was fun for their daughters. Girls’ overweight status was not associated with girls’ reports of minutes spent per week in PA or WBPA. Discussion: The present study's findings of lower WBPA self‐efficacy, lack of enjoyment of WBPA, and higher perceived social influence to do WBPA among overweight girls suggest that efforts are needed to promote physical competencies and positive perceptions of PA among overweight girls.     

RETRACTION: C-reactive Protein and Metabolic Syndrome in Youth: A Strong Relationship?

Retraction: Note from the Editor‐in‐Chief: This paper is retracted Objective: Metabolic syndrome (MS) is on the rise in youth. As high‐sensitivity C‐reactive protein (hs‐CRP) is associated with cardiovascular/metabolic disorders, we evaluated the association between MS and its components and hs‐CRP in a sample of Brazilian overweight and obese youth. Methods and Procedures: A total of 407 students (229 girls, 273 with excessive weight, 11.3 ± 3.2 years) were evaluated. Measurement included BMI, waist circumference (WC), blood pressure, lipids, insulin, and hs‐CRP. Excessive weight was defined using BMI z ‐score; MS by the modified National Cholesterol Education Program—Adult Treatment Panel III. Results: Subjects were classified into two groups: with MS (n = 72) and without (n = 335). hs‐CRP means and medians were higher in MS group (1.41 mg/l vs. 1.06 mg/l, P < 0.001; 2.21 mg/l vs. 1.23 mg/l, P < 0.001). Associations between hs‐CRP quartiles and insulin resistance (IR) (P < 0.001), MS (P < 0.001), WC (P < 0.000), BMI z‐score (P < 0.001), hypertension (P < 0.001), hypertriglyceridemia (P < 0.001), and low HDL‐c (P = 0.023) were significant; adjustment of hs‐CRP for BMI z‐score eliminated the previous association, except for the number of MS components (nMSc) (P < 0.001). Adjusting for homeostasis model assessment method of IR (HOMA‐IR) did not eliminate the relation between hs‐CRP and MS components. Furthermore, increases in BMI z ‐score and nMSc were associated with an increased hs‐CRP. Excessive weight (odds ratio (OR), 7.9; confidence interval (CI), 4.7–13.4; P = 0.000), hypertension (OR, 2.3; CI, 1.3–4.2; P = 0.003), and hypertriglyceridemia (OR, 2.3; CI, 1.5–3.7; P < 0.001) were independently associated with hs‐CRP. Discussion: In youth, hs‐CRP is strongly related with MS and its components, and is also determined by the body composition. This association indicates a precocious proinflammatory state.     

The Influence of Overweight and Obesity on Longitudinal Trends in Maternal Serum Leptin Levels During Pregnancy

Maternal obesity influences a number of metabolic factors that can affect the course of pregnancy. Among these factors, leptin plays an important role in energy metabolism and fetal development during pregnancy. Our objective was to estimate the influence of maternal overweight/obesity on variation in the maternal serum leptin profile during pregnancy. In a prospective cohort of 143 adult gravidas with singleton pregnancies presenting for general prenatal care, we measured serum leptin levels at 6–10, 10–14, 16–20, 22–26, and 32–36 weeks' gestation. The longitudinal effects of maternal prepregnancy BMI, categorized as nonoverweight (≤26.0 kg/m²) and overweight/obese (>26.0 kg/m²), on serum leptin concentration were analyzed using linear mixed models. Overweight/obese women had significantly higher serum leptin concentrations than their nonoverweight counterparts throughout pregnancy (P < 0.01). Although these concentrations increased significantly across gestation for both groups, the rate of increase was significantly smaller for overweight/obese women (P < 0.05). To investigate whether these differences merely reflected differences in weight‐gain patterns between the two groups, we examined an index of leptin concentration per unit body weight (leptin (ng/ml)/weight (kg)). Overweight/obese women had a significantly higher index throughout pregnancy (P < 0.01). However, although this index increased significantly across pregnancy for nonoverweight women, it actually decreased significantly for overweight/obese women (P < 0.01). Our results suggest that factors other than fat mass alone influence leptin concentrations in overweight/obese women compared to normal‐weight women during pregnancy. Such factors may contribute to differences in the intrauterine environment and its influence on pregnancy outcomes in the two groups.     

Intensive Lifestyle Intervention Improves Physical Function Among Obese Adults With Knee Pain: Findings From the Look AHEAD Trial

Lifestyle interventions have resulted in weight loss or improved physical fitness among individuals with obesity, which may lead to improved physical function. This prospective investigation involved participants in the Action for Health in Diabetes (Look AHEAD) trial who reported knee pain at baseline (n = 2,203). The purposes of this investigation were to determine whether an Intensive Lifestyle Intervention (ILI) condition resulted in improvement in self‐reported physical function from baseline to 12 months vs. a Diabetes Support and Education (DSE) condition, and whether changes in weight or fitness mediated the effect of the ILI. Outcome measures included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, stiffness, and physical function subscales, and WOMAC summary score. ILI participants exhibited greater adjusted mean weight loss (s.e.) vs. DSE participants (?9.02 kg (0.48) vs. ?0.78 kg (0.49); P < 0.001)). ILI participants also demonstrated more favorable change in WOMAC summary scores vs. DSE participants (β (s.e.) = ?1.81 (0.63); P = 0.004). Multiple regression mediation analyses revealed that weight loss was a mediator of the effect of the ILI intervention on change in WOMAC pain, function, and summary scores (P < 0.001). In separate analyses, increased fitness also mediated the effect of the ILI intervention upon WOMAC summary score (P < 0.001). The ILI condition resulted in significant improvement in physical function among overweight and obese adults with diabetes and knee pain. The ILI condition also resulted in significant weight loss and improved fitness, which are possible mechanisms through which the ILI condition improved physical function.     

Prevalence of Overweight among Inner City Hispanic‐American Children and Adolescents

Objective: National surveys have pointed to a particularly high risk of pediatric overweight among U.S. Hispanics. However, the data have been primarily from the Mexican‐American community. We studied the prevalence of overweight and clinical comorbidities in children and youth of predominantly El Salvadoran ancestry. Research Methods and Procedures: A sample of 309 Hispanic youth, 6–18 years was surveyed from two inner city Washington, DC, clinics. BMI; triceps skinfold (TSF) and subscapular skinfold thickness (SSSF); bioelectrical impedance analysis (BIA); and blood pressure measures were obtained, along with information regarding physical activity, sedentary behavior, dietary history, family, and personal medical history. Results: Thirty‐eight percent were overweight (BMI ≥ 95th percentile) and 22% at risk for overweight (BMI 85–94th percentile). Thirty‐four percent had TSF ≥ 90th percentile and 29% had SSSF ≥ 90th percentile. Fifty‐one percent of males and 70% of females had body fat > 30%. Compared to their nonoverweight counterparts, overweight youth had significantly higher systolic blood pressure (111.4 ± 1.3 vs. 104.5 ± 0.9 mm Hg, p < 0.0001). Among children younger than 11 years, overweight was associated with onset of adrenarche (23% vs. 10%, p = 0.01). Participation in one or more sports teams was negatively correlated with overweight) p = 0.04). Discussion: The prevalence of overweight and at risk for overweight in this sample was twice the national average for U.S. children and 1.7 times greater than that of Mexican‐American children in national surveys. Overweight was associated with advanced pubertal development, high body fat, elevated blood pressure, and decreased sports participation.     

Associations among Active Transportation,Physical Activity,and Weight Status in Young Adults

Objective: To describe prevalence of active, public, and car transit by overweight status and amount of leisure‐time physical activity in a nationally representative cohort of ethnically diverse young adults. Research Methods and Procedures: Questionnaire data on patterns of transportation were collected from U.S. adolescents enrolled in Wave III (2001) of the National Longitudinal Study of Adolescent Health (N = 10, 771). Measured height and weight data were used to calculate BMI and classify adults by overweight status (BMI ≥ 25). Self‐reported physical activity data were used to classify adults into those who achieved ≥ 5 bouts of weekly moderate‐vigorous physical activity and those who did not. Results were stratified by overweight and physical activity status. Results: The vast majority of young adults used car transit (work, 90.4%; school, 74.7%). A small proportion of young adults used active means of transportation to work (8.1%) and school (26.7%), and fewer used public transportation to work or school (<10%). The proportion of individuals using active transportation was higher among the nonoverweight traveling to work (9.2%) and school (29.7%) and among the more active traveling to work (15.2%) and school (37.0%) relative to the overweight and less active young adults. Discussion: The vast majority of young adults of all racial/ethnic backgrounds, particularly blacks and Hispanics, did not use active transportation to school and/or work. Active transportation was more common among nonoverweight and more active young adults, of high socioeconomic status, particularly full‐time students. Population‐level efforts (and environmental supports) to increase non‐leisure physical activity, particularly active transportation, are sorely needed as a means of supporting and promoting overall physical activity.     

The Chronic Effects of Whey Proteins on Blood Pressure,Vascular Function,and Inflammatory Markers in Overweight Individuals

Limited evidence suggests that dairy whey protein may be the major dairy component that is responsible for health benefits currently associated with increased dairy consumption. Whey proteins may reduce blood pressure and improve cardiovascular health. This study evaluated the effects of whey protein supplementation on blood pressure, vascular function and inflammatory markers compared to casein and glucose (control) supplementation in overweight/obese individuals. The subjects were randomized to either whey protein, casein or glucose supplementation for 12 weeks according to a parallel design. In all, 70 men and women with a mean (±s.e.m.) BMI (kg/m²) of 31.3 ± 0.8 completed the study. Systolic blood pressure (SBP) decreased significantly at week 6 compared to baseline in the whey and casein groups, (P = 0.028 and P = 0.020, respectively) and at week 12 (P = 0.020, and P = 0.017, respectively). Diastolic blood pressure (DBP) decreased significantly compared to baseline in the whey and casein groups (P = 0.038 and P = 0.042, respectively) at week 12. DBP decreased significantly in the whey and casein groups (P = 0.025, P = 0.038, respectively) at week 12 compared to the control group. Augmentation index (AI) was significantly lower from baseline at 12 weeks (P = 0.021) in the whey group. AI decreased significantly in the whey group at 12 weeks compared to control (P = 0.006) and casein (P = 0.006). There were no significant changes in inflammatory markers within or between groups. This study demonstrated that supplementation with whey protein improves blood pressure and vascular function in overweight and obese individuals.     

High‐density Lipoprotein Apolipoprotein A‐I Kinetics in Obesity

Objective: Low plasma concentrations of high‐density lipoprotein (HDL)‐cholesterol and apolipoprotein A‐I (apoA‐I) are independent predictors of coronary artery disease and are often associated with obesity and the metabolic syndrome. However, the underlying kinetic determinants of HDL metabolism are not well understood. Research Methods and Procedures: We pooled data from 13 stable isotope studies to investigate the kinetic determinants of apoA‐I concentrations in lean and overweight—obese individuals. We also examined the associations of HDL kinetics with age, sex, BMI, fasting plasma glucose, fasting insulin, Homeostasis Model Assessment score, and concentrations of apoA‐I, triglycerides, HDL‐cholesterol and low‐density lipoprotein‐cholesterol. Results: Compared with lean individuals, overweight—obese individuals had significantly higher HDL apoA‐I fractional catabolic rate (0.21 ± 0.01 vs. 0.33 ± 0.01 pools/d; p < 0.001) and production rate (PR; 11.3 ± 4.4 vs. 15.8 ± 2.77 mg/kg per day; p = 0.001). In the lean group, HDL apoA‐I PR was significantly associated with apoA‐I concentration (r = 0.455, p = 0.004), whereas in the overweight—obese group, both HDL apoA‐I fractional catabolic rate (r = ?0.396, p = 0.050) and HDL apoA‐I PR (r = 0.399, p = 0.048) were significantly associated with apoA‐I concentration. After adjustment for fasting insulin or Homeostasis Model Assessment score, HDL apoA‐I PR was an independent predictor of apoA‐I concentration. Discussion: In overweight—obese subjects, hypercatabolism of apoA‐I is paralleled by an increased production of apoA‐I, with HDL apoA‐I PR being the stronger determinant of apoA‐I concentration. This could have therapeutic implications for the management of dyslipidemia in individuals with low plasma HDL‐cholesterol.     

C-reactive protein modifies the association of plasma leptin with coronary calcium in asymptomatic overweight individuals

Evidence suggests putative interactions of leptin and C‐reactive protein (CRP) in the pathogenesis of adiposity‐related atherosclerotic cardiovascular disease (CVD). Therefore, we investigated whether CRP levels modify the relationship of leptin levels with coronary artery calcium (CAC). We examined 1,460 asymptomatic individuals from two community‐based cross‐sectional studies coordinated at a single, university‐based research center. We focused on subjects who were overweight or obese (BMI ≥25) given greater biologic plausibility in this setting. In multivariable CAC models, we analyzed the interaction of log‐transformed plasma leptin levels with higher CRP levels as defined by three cut‐points: two clinically based (2 mg/l, 3 mg/l) and one dataset specific (sex‐specific upper quartile). The association of plasma leptin with CAC was modified by higher CRP regardless of cut‐point (interaction term P values all <0.01 in fully adjusted models). Leptin levels were associated with CAC in those with high, but not low CRP levels (e.g., tobit ratio for a 1 unit increase in ln(leptin) (95% CI): 2.18 (1.29–3.66) if CRP level ≥3 mg/l; N = 461 vs. 0.94 (0.67–1.31) if CRP levels <3 mg/l; N = 999) in fully adjusted models. No interaction with CRP was present in control analyses with adiponectin, BMI and waist circumference. In conclusion, in asymptomatic overweight and obese adults, increased leptin levels were independently associated with increased CAC in the presence of high, but not low CRP levels, supporting a leptin‐CRP interface in atherosclerosis risk.     

Weight loss can lead to resolution of gastroesophageal reflux disease symptoms: A prospective intervention trial

Objective: Weight gain is an important risk factor for gastroesophageal reflux disease (GERD); however, whether weight loss can lead to resolution of GERD symptoms is not clear. Our aim was to measure the impact of weight loss on GERD symptoms. Design and Methods: In a prospective cohort study at a tertiary referral center, overweight/obese subjects (BMI 25‐39.9 kg/m2) were enrolled in a structured weight loss program. Weight loss strategies included dietary modifications, increased physical activity and behavioral changes. At baseline and at 6 months, BMI and waist circumference were measured and all participants completed a validated reflux disease questionnaire. Results: A total of 332 adult subjects, mean age 46 years and 66% women were prospectively enrolled. At baseline, the mean body weight, BMI, and waist circumference were 101 (±18) kg, 35 (±5) kg/m2 and 103 (±13) cm. At 6 months, majority of the subjects (97%) lost weight (average weight loss: 13 ± 7.7 kg) and as compared with baseline, there was a significant decrease in the overall prevalence of GERD (15 vs. 37%; P < 0.01) and the mean GERD symptom score (1.8 vs. 5.5; P < 0.01). Overall, 81% of the subjects had reduction in GERD symptom scores; 65% had complete resolution and 15% had partial resolution of reflux symptoms. There was a significant correlation between % body weight loss and reduction in GERD symptom scores (r = 0.17, P < 0.05). Conclusions: In conclusion, the overall prevalence of GERD symptoms is high (37%) in overweight and obese subjects. A structured weight loss program can lead to complete resolution of GERD symptoms in the majority of these subjects.     

Oxidant Stress in Healthy Normal‐weight,Overweight, and Obese Individuals

This study was undertaken to investigate the association among BMI and lipid hydroperoxide (LH), total antioxidant status (TAS), superoxide dismutase (SOD), and reduced glutathione (GSH). Ninety (n = 90) healthy males and females (n = 23/67) (29 normal weight (BMI: 22.74 ± 0.25 kg/m²), 36 overweight (BMI: 27.18 ± 0.23 kg/m²), and 25 obese (33.78 ± 0.48 kg/m²)) participated in the study. Data collected included anthropometric measures, fasting blood glucose, lipid profile, LH, TAS, and enzymatic antioxidants (SOD, and reduced GSH). The results of the study showed that obese individuals had significantly increased LH levels compared to normal‐weight individuals (obese vs. normal weight (0.88 ± 0.05 vs. 0.67 ± 0.03 µmol/l, P < 0.01)) but the increased levels were not significantly different when compared to the overweight group (obese vs. overweight (0.88 ± 0.05 vs. 0.79 ± 0.05 µmol/l)). No other consistent significant differences in TAS, SOD, and GSH were identified between groups. This study concluded that only obesity and not moderate overweight elevates LH levels. Furthermore, the levels of TAS, SOD, and GSH in obesity do not explain the increased LH levels observed in obesity.     

Evaluation of a multisensor armband in estimating energy expenditure in obese individuals

Objective: To examine the reliability and validity of the SenseWear Pro 2 Armband (SWA; Body Media, Pittsburgh, PA) during rest and exercise compared with indirect calorimetry (IC) in obese individuals. Research Methods and Procedures: Energy expenditure was assessed during rest with the SWA and IC in 142 obese adults (37 men and 105 women, BMI = 42.3 ± 7.0) and in 25 lean and overweight adults (BMI = 25.3 ± 3.2) who were used as a comparison group. Twenty‐nine of the obese adults also participated in three separate short exercise sessions including cycle ergometry, stair stepping, and treadmill walking. Results: The repeatability of SWA estimates in obese subjects was high (r = 0.88, p < 0.001). The SWA generally underestimated the resting energy expenditure (REE) (1811 ± 346 vs. 1880 ± 382 kcal/d) and highly overestimated the energy expenditure during the exercise sessions in obese individuals. REE estimations by SWA were significantly correlated with fat‐free mass (r = 0.88, p < 0.001). Bland‐Altman plots based statistical analysis for the estimated REE, and measured IC showed a low agreement (Total Error > 20% but Systematic Error < 5%) between the two methods in obese subjects, although they showed a high correlation and a very good agreement in lean and overweight patients. Discussion: The SWA is an easy to handle, practical, new portable device for measuring energy expenditure. The accuracy of the SWA appeared to be poor in the obese subjects we examined, especially those with high REE both in rest and exercise. We believe that it is necessary to incorporate new, obesity‐specific algorithms in the relative software.     

Overweight and Obesity: Prediction by Silhouettes in Young Adults

The present study analyzes the prevalence of overweight/obesity in a sample of young adults from the University of the Basque Country (Spain), and tests the efficiency of the silhouettes to predict overweight/obesity. This cross‐sectional study was conducted in a sample of volunteer university students from the University of the Basque Country (356 men and 745 women, age: 18–33 years), who came to the Physical Anthropology laboratory where a standardized questionnaire was administered and anthropometric measurements were taken by a well‐trained anthropometrist. Height and weight were obtained. BMI was calculated as weight/height² (kg/m²) and it was used as a reference method. Using a questionnaire, based on the standard figural stimuli, subjects were asked to choose the silhouette which was closest to his/her usual appearance (current body size). The accuracy of the Williamson et al.'s silhouettes as an overweight‐obesity indicator was analyzed by gender‐specific receiver operating curve (ROC). The cutoff figure to distinguish between nonoverweight and overweight‐obese individuals corresponded to number 7 in men and 6 in women. These cutoff values matched optimal sensitivity and specificity, with few nonoverweight subjects selecting silhouettes bigger than 7 in the case of men or 6 for women. In conclusion, the figural stimuli allows the identification of populations at overweight/obesity risk with the simple use of silhouettes, at least in this rank of age, where the overweight and obesity are yet little frequent.     

Ambulant 24‐h glucose rhythms mark calendar and biological age in apparently healthy individuals

Glucose metabolism marks health and disease and is causally inferred in the aging process. Ambulant continuous glucose monitoring provides 24‐h glucose rhythms under daily life conditions. We aimed to describe ambulant 24‐h glucose rhythms measured under daily life condition in relation to calendar and biological age in apparently healthy individuals. In the general population and families with propensity for longevity, we studied parameters from 24‐h glucose rhythms; glucose levels; and its variability, obtained by continuous glucose monitoring. Participants were 21 young (aged 22–37 years), 37 middle‐aged (aged 44–72 years) individuals from the general population, and 26 middle‐aged (aged 52–74 years) individuals with propensity for longevity. All were free of diabetes. Compared with young individuals, middle‐aged individuals from the general population had higher mean glucose levels (5.3 vs. 4.7 mmol L^?1, P < 0.001), both diurnally (P < 0.001) and nocturnally (P = 0.002). Glucose variability was higher in the middle‐aged compared with the young (standard deviation 0.70 vs. 0.57 mmol L^?1, P = 0.025). Compared with middle‐aged individuals from the general population, middle‐aged individuals with propensity for longevity had lower overall mean glucose levels (5.2 vs. 5.4 mmol L^?1, P = 0.047), which were more different nocturnally (4.8 vs. 5.2 mmol L^?1, P = 0.003) than diurnally (5.3 vs. 5.5 mmol L^?1, P = 0.14). There were no differences in glucose variability between these groups. Results were independent of body mass index. Among individuals without diabetes, we observed significantly different 24‐h glucose rhythms depending on calendar and biological age.     

One-year changes in symptoms of depression and weight in overweight/obese individuals with type 2 diabetes in the Look AHEAD study

Depressed individuals are frequently excluded from weight loss trials because of fears that weight reduction may precipitate mood disorders, as well as concerns that depressed participants will not lose weight satisfactorily. The present study examined participants in the Look AHEAD study to determine whether moderate weight loss would be associated with incident symptoms of depression and suicidal ideation, and whether symptoms of depression at baseline would limit weight loss at 1 year. Overweight/obese adults with type 2 diabetes (n = 5,145) were randomly assigned to an Intensive Lifestyle Intervention (ILI) or a usual care group, Diabetes Support and Education (DSE). Of these, 5,129 participants completed the Beck Depression Inventory (BDI) and had their weight measured at baseline and 1 year. Potentially significant symptoms of depression were defined by a BDI score ≥10. Participants in ILI lost 8.6 ± 6.9% of initial weight at 1 year, compared to 0.7 ± 4.8% for DSE (P < 0.001, effect size = 1.33), and had a reduction of 1.4 ± 4.7 points on the BDI, compared to 0.4 ± 4.5 for DSE (P < 0.001, effect size = 0.23). At 1 year, the incidence of potentially significant symptoms of depression was significantly lower in the ILI than DSE group (6.3% vs. 9.6%) (relative risk (RR) = 0.66, 95% confidence interval (CI) = 0.5, 0.8; P < 0.001). In the ILI group, participants with and without symptoms of depression lost 7.8 ± 6.7% and 8.7 ± 6.9%, respectively, a difference not considered clinically meaningful. Intentional weight loss was not associated with the precipitation of symptoms of depression, but instead appeared to protect against this occurrence. Mild (or greater) symptoms of depression at baseline did not prevent overweight/obese individuals with type 2 diabetes from achieving significant weight loss.     

Weight Goals in a College‐age Population

Objective: Although a growing body of literature has found unrealistic weight loss goals to be common among older, primarily female, subjects, little is known about weight loss goals of younger adults. Research Methods and Procedures: Three hundred seventy‐nine college students had their height and weight taken and reported their “goal,” “dream,” “happy,” “acceptable,” and “disappointed” weights. A series of 2 (gender) × 2 (nonoverweight vs. overweight) ANOVAs were conducted with both absolute weight goals and percentage of weight loss needed to obtain those goals as dependent variables. Results: When examined in terms of absolute weight goals, women generally had lower body mass index (BMI) goals than men, and nonoverweight participants had lower BMI goals than overweight participants. Surprisingly, most overweight participants would accept a weight loss that would still place them in the overweight BMI range. When examined in terms of percentage loss needed to reach those goals, only overweight women chose goal and dream weights that would require a loss greater than can be expected from nonsurgical weight‐loss treatments, and all overweight participants chose happy and acceptable weights within 15% of current weight. Discussion: Participants in this study had generally reasonable weight‐loss goals, and even the most extreme weight loss goals were much more moderate than those found in previous studies. These results are surprising given the extreme social pressures for thinness facing young adults. Future studies should examine the variables that influence selection of goal weights and how goal weights affect actual dieting behavior.     

Overweight Children's Barriers to and Support for Physical Activity

Objective: As the epidemic of overweight increases among youth, research needs to examine factors that may influence children's participation in weight‐related health behaviors. This study examined overweight children's perceived barriers to and support for physical activity compared with nonoverweight children. Research Methods and Procedures: Barriers to and support for physical activity were examined among 84 overweight children attending a summer fitness camp or a university‐based weight loss clinic. Barriers and support levels were then compared with those of 80 nonoverweight children of a similar age range. Results: Body‐related barriers were the most predominant barrier type among overweight youth, especially among overweight girls. Overweight children, particularly girls, reported significantly higher body‐related, resource, and social barriers to physical activity compared with nonoverweight children and lower levels of adult support for physical activity. Discussion: Overweight children may be particularly vulnerable to body‐related barriers to physical activity, and reducing such barriers may serve as physical activity intervention points most relevant for overweight youth. Future interventions may also benefit from enhancing support for physical activity from adults and peers.     

Childhood Overweight and Academic Performance: National Study of Kindergartners and First‐Graders

Objective: To examine the association between children's overweight status in kindergarten and their academic achievement in kindergarten and first grade. Research Methods and Procedures: The data analyzed consisted of 11, 192 first time kindergartners from the Early Childhood Longitudinal Study, a nationally representative sample of kindergartners in the U.S. in 1998. Multivariate regression techniques were used to estimate the independent association of overweight status with children's math and reading standardized test scores in kindergarten and grade 1. We controlled for socioeconomic status, parent‐child interaction, birth weight, physical activity, and television watching. Results: Overweight children had significantly lower math and reading test scores compared with nonoverweight children in kindergarten. Both groups were gaining similarly on math and reading test scores, resulting in significantly lower test scores among overweight children at the end of grade 1. However, these differences, except for boys’ math scores at baseline (difference = 1.22 points, p = 0.001), became insignificant after including socioeconomic and behavioral variables, indicating that overweight is a marker but not a causal factor. Race/ethnicity and mother's education were stronger predictors of test score gains or levels than overweight status. Discussion: Significant differences in test scores by overweight status at the beginning of kindergarten and the end of grade 1 can be explained by other individual characteristics, including parental education and the home environment. However, overweight is more easily observable by other students compared with socioeconomic characteristics, and its significant (unadjusted) association with worse academic performance can contribute to the stigma of overweight as early as the first years of elementary school.     

Ethnic and sex variations in overweight self-perception: relationship to sedentariness

Objective: With increasing frequency, health promotion messages advocating physical activity are claiming weight loss as a benefit. However, messages promoting physical activity as a weight loss strategy may have limited effectiveness and cross‐cultural relevance. We recently found self‐perceived overweight to be a more robust correlate of sedentary behavior than BMI in Los Angeles County adults. In this study, we examined ethnic and sex differences in overweight self‐perception and their association with sedentariness in this sample. Research Methods and Procedures: We conducted bivariate and multivariate analyses of cross‐sectional survey data from a representative sample of Los Angeles County adults. Results: Women were more likely to perceive themselves to be overweight than men overall (73.2% of overweight/non‐obese and 24.1% of average weight women vs. 44.5% of overweight/non‐obese and 5.6% of average weight men) and within each ethnic group. African‐Americans were least likely (41.3% of overweight/non‐obese African‐Americans self‐identified as overweight) and whites were most likely to consider themselves overweight (60.6% of overweight/non‐obese whites self‐identified as overweight). Overweight (vs. average weight) self‐perception was correlated with sedentariness among average weight adults (45.3% vs. 33.0%, p < 0.001), overweight adults (43.4% vs. 33.6%, p < 0.001), men (average and overweight: 38.4% vs. 27.8%, p < 0.001), overweight whites (41.9% vs. 29.7%, p = 0.0012), and African‐Americans and Latinos (41.6% vs. 33.9%, p = 0.005). Discussion: These data suggest that our society's emphasis on weight loss rather than lifestyle change may inadvertently discourage physical activity adoption/maintenance among non‐obese individuals. However, further research is needed, particularly from prospective cohort and intervention studies, to elucidate the relationship between overweight self‐perception and healthy lifestyle change.     

Physical activity intensity and risk of overweight and adiposity in children

Background: Physical activity recommendations for children focus on duration of activity and underemphasize intensity. Objective: To evaluate the relationship between physical activity (intensity and duration) and the odds of being overweight, >20% body fat and >25% body fat. Methods and Procedures: Body fat, BMI and physical activity (accelerometry) were measured in children (n = 251) aged 8–10 years. Physical activity was quantified as time in moderate physical activity (MPA) and vigorous physical activity (VPA). Results: Prevalence of overweight and obesity were 18 and 11.6%, respectively. Regression indicated that VPA, not MPA, is associated with body fat (r = 0.35, P < 0.001) and BMI (r = 0.26, P < 0.001). Odds ratio demonstrated a significant impact of MPA and VPA on body composition. Children performing ≤ 5 min/day of VPA are 4.0 times more likely to have ≥ 20% body fat (P < 0.001), 2.9 times more likely to have ≥ 25% body fat (P < 0.05) and 5.2 times more likely to be classified as overweight (P < 0.01) compared to children performing ≥ 15 min/day. Those performing ≤ 15 min/day of MPA vs. >45 min/day MPA are at 4.2 increased odds of having ≥ 20% body fat (P < 0.001), and 3.0 increased odds of having ≥ 25% (P < 0.01). Discussion: Lower durations of both MPA and VPA are associated with increased odds of overweight and adiposity. Forty‐five minutes of MPA and fifteen minutes of VPA were associated with reduced body fat and BMI. We recommend that these amounts are used to develop minimum physical activity intensity guidelines for the prevention and treatment of obesity.