Research examined joint physical activity and sedentary behavior among 291 parent-child pairs who both wore an accelerometer and global positioning systems (GPS) device over the same 7-day period.
Children were 52.2% female, 8-14 years, and 43.0% Hispanic. Parents were 87.6% female. An Actigraph GT2M accelerometer and GlobalSat BT-335 GPS device collected activity and global positioning data, respectively. Linear distance between the parent and child for each 30-sec. epoch was calculated using geographic coordinates from the GPS. Joint behavior was defined as a separation distance less than 50m between parents and children.
On average during non-school waking hours, parents and children spent 2.4 min. (SD = 4.1) per day performing moderate-to-vigorous physical activity (MVPA) together and 92.9 min. (SD = 40.1) per day in sedentary behavior together. Children engaged in an average of 10 min. per day of MVPA during non-school waking hours when their parent was nearby but not engaging in MVPA. During this same period, parents engaged in 4.6 min. per day of MVPA when their child was nearby but not engaging in MVPA. Household income level and the child’s age were negatively associated with joint MVPA. Girls engaged in a greater percentage of their total MVPA together with their parent than boys. Girls and older children engaged in more sedentary behavior together with their parent than boys and younger children. Older parents engaged in a greater percentage of their sedentary behavior together with their children than younger parents.
Replacing the time that parents and children spend together in sedentary pursuits with joint physical activity could have health benefits, especially for girls, older children, older parents, and higher income families.
moderate-to-vigorous physical activity; accelerometer; global positioning systems; age; sex
The current article reports a large scale study of the prediction of marijuana use cessation among individuals attending alternative high schools who were regular users at baseline. Based on the Triadic Influence Theory, predictors of marijuana use cessation at 1-year follow-up were organized by type of influence (e.g., interpersonal, cultural and attitudinal, and intrapersonal) and level of influence (e.g., distal and ultimate). Among the 522 students who were past 30-day marijuana users at baseline, quitting was defined as having not used marijuana in the last 30 days at 1-year follow-up (43% of baseline users). To account for the level of influence we employed a theory-based analytic strategy, hierarchical regression. In the final multivariate model, lower level of baseline marijuana use and less of a likelihood to endorse pro-drug-use myths remained predictors of marijuana use cessation 1-year later. Implications of these findings include the need to develop cessation programs that reduce psychological dependence on marijuana use, and correct cognitive misperceptions about drug use in order to help adolescents make decisions that lead to health-promoting behaviors.
marijuana; cessation; adolescents; youth; cannabis; self-initiated; predictors
In adults, there is evidence that physical activity effectively improves insulin sensitivity regardless of adiposity. Whether this is also the case in children and adolescents has been less clear. Whether this is also the case in children and adolescents is less clear. Clarifying this matter may help to identify the best outcomes to target in exercise programs for these age groups, where changes in adiposity may not always be desirable or realistic. A review of the literature was conducted on studies that examined the relationships of physical activity, cardiorespiratory fitness and strength with insulin sensitivity independent of adiposity in children and adolescents. Experimental (intervention) and correlational (longitudinal and cross-sectional) studies on participants ages 18 and younger were identified. A total of 42 studies were included in this review. Sample sizes in the studies ranged from 14 to 4,955 participants, with individual ages ranging from 5 to 19 years. A significant relationship with SI existed in 78% of studies on physical activity, 69% of studies on cardiorespiratory fitness and 66% of studies on strength. In studies that examined both physical activity and cardiorespiratory fitness concurrently, evidence suggests that they are both correlated with insulin sensitivity independent of adiposity, especially when physical activity is at higher intensities. However the strength of this relationship might be influenced by study design, measurement techniques and participant characteristics. This is the first review of its type to take research design into account, and to examine study outcomes according to participant ethnicity, gender, age, pubertal status and weight status.
The present study tested the efficacy of motivational interviewing-based booster sessions for Project Towards No Drug Abuse (TND), a 12-session school-based curriculum targeting youth at risk for drug abuse. In addition, generalization of effects to risky sexual behavior was assessed. The one-year outcomes evaluation of the project is presented.
A total of 24 schools were randomized to one of three conditions: Standard Care Control (SCC), TND classroom program only (TND-only), and TND plus Motivational Interviewing booster (TND+MI). A total of 1186 participants completed baseline and one-year follow-up surveys. Following the classroom program, youth in the TND+MI condition received up to three sessions of MI in person or by telephone. Effects were examined on 30-day cigarette, alcohol, marijuana, and hard drug use, as well as measures of risky sexual behavior (number of sex partners, condom use, having sex while using drugs or alcohol).
Collapsed across the two program conditions, results showed significant reductions in alcohol, hard drug use, and cigarette smoking, relative to controls. These effects held for an overall substance use index. The MI booster component failed to achieve significant incremental effects above and beyond the TND classroom program. No effects were found on risky sexual behavior.
While the program effects of previous studies were replicated, the study failed to demonstrate that an adequately implemented MI booster was of incremental value at one-year follow-up.
one-year follow-up; drug prevention; continuation high schools; Motivational Interviewing; boosters
This study assessed the changes in time spent in moderate to vigorous physical activity (MVPA) on fat depots, insulin action, and inflammation. Longitudinal data were generated from 66 Hispanic adolescents (15.6±1.1 yr; BMI percentile 97.1±3.0) who participated in a 16-wk nutrition or nutrition+exercise intervention. There were no effects of the intervention on PA, but there were inter-individual changes in PA. For purposes of this analysis, all intervention groups were combined to assess how changes in PA during 16 wk affected changes in adiposity, insulin action, and markers of inflammation. MVPA was assessed by 7-day accelerometry, total body fat via DXA, liver fat by MRI, and insulin, glucose and HOMA-IR via a fasting blood draw. A repeated measures ANCOVA was used to assess the effect of MVPA on fat depots, insulin action, and inflammatory markers. Sixty-two percent of participants increased MVPA (mean increase, 19.7±16.5 min/day) and 38% decreased MVPA (mean decrease, 10.7±10.1 min/day). Those who increased MVPA by as little as 20 min per day over 16 wk, compared to those who decreased MVPA, had significant reductions in liver fat (−13% vs. +3%; P=0.01), leptin levels (−18% vs. +4%; P=0.02), and fasting insulin (−23% vs. +5%; P=0.05). These findings indicate that a modest increase in MVPA can improve metabolic health in sedentary overweight Hispanic adolescents.
Moderate-to-Vigorous Physical Activity; Obesity
Purpose. It is unclear whether sociocultural and socioeconomic factors are directly linked to type 2 diabetes risk in overweight/obese ethnic minority children and adolescents. This study examines the relationships between sociocultural orientation, household social position, and type 2 diabetes risk in overweight/obese African-American (n = 43) and Latino-American (n = 113) children and adolescents. Methods. Sociocultural orientation was assessed using the Acculturation, Habits, and Interests Multicultural Scale for Adolescents (AHIMSA) questionnaire. Household social position was calculated using the Hollingshead Two-Factor Index of Social Position. Insulin sensitivity (SI), acute insulin response (AIRG) and disposition index (DI) were derived from a frequently sampled intravenous glucose tolerance test (FSIGT). The relationships between AHIMSA subscales (i.e., integration, assimilation, separation, and marginalization), household social position and FSIGT parameters were assessed using multiple linear regression. Results. For African-Americans, integration (integrating their family's culture with those of mainstream white-American culture) was positively associated with AIRG (β = 0.27 ± 0.09, r = 0.48, P < 0.01) and DI (β = 0.28 ± 0.09, r = 0.55, P < 0.01). For Latino-Americans, household social position was inversely associated with AIRG (β = −0.010 ± 0.004, r = −0.19, P = 0.02) and DI (β = −20.44 ± 7.50, r = −0.27, P < 0.01). Conclusions. Sociocultural orientation and household social position play distinct and opposing roles in shaping type 2 diabetes risk in African-American and Latino-American children and adolescents.
To assess the effects of a maintenance program (monthly newsletters versus monthly group classes and telephone behavioral sessions) on obesity and metabolic disease risk at one year in overweight minority adolescents.
After a 4-month nutrition and strength training intervention, 53 overweight Latino and African American adolescents (15.4 ±1.1 yrs) were randomized into one of two maintenance groups for 8 months: monthly newsletters (n=23) or group classes (n=30; monthly classes + individualized behavioral telephone sessions). The following outcomes were measured at months 4 (immediately following the intense intervention) and month 12: height, weight, blood pressure, body composition via BodPod™, lipids and glucose/insulin indices via frequently sampled intravenous glucose tolerance test (FSIVGTT).
There were no significant group by time interactions for any of the health outcomes. There were significant time effects in several outcomes for both groups from month 4 to 12: bench press and leg press decreased by 5% and 14% (p=0.004 & p=0.01), fasting insulin and acute insulin response decreased by 26% and 16% (p<0.001 & p=0.046); while HDL cholesterol and insulin sensitivity improved by 5% and 14% (p=0.042 and p=0.039).
Newsletters as opposed to group classes may suffice as follow-up maintenance programs to decrease type 2 diabetes and cardiovascular risk in overweight minority adolescents.
Maintenance; Obesity Intervention; Type 2 Diabetes; Cardiovascular risk factors; Latino and African American adolescents
The United States is currently in an age of obesity and inactivity despite increasing public awareness and scientific knowledge of detrimental long-term health effects of this lifestyle. Behavior-tracking diaries offer an effective strategy for physical activity adherence and weight management. Furthermore, Web-based physical activity diaries can engage meaningful partners in people’s social networks through fun online gaming interactions and generate motivational mechanisms for effective behavioral change and positive health outcomes.
Wellness Partners (WP) is a Web-based intervention in the form of a physical activity diary with social networking and game features. Two versions were designed and developed for the purpose of this study—“Diary” only and “Diary+Game”. The objectives of this study included pilot testing the research process of this intervention design, implementation, evaluation, and exploring the effectiveness of social gaming features on adult participants’ physical activity and anthropometric measures.
We conducted a field experiment with randomized crossover design. Assessments occurred at baseline, first follow-up (FU, 5-8 weeks after using one version of WP), and second FU (5-8 weeks of using the other version of WP). In the control condition, participants started with the “Diary” version of WP while in the experimental condition, participants started with the “Diary+Game” version of WP. A total of 54 adults (egos) ages 44-88, and their family and friends (alters) ages 17-69 participated in the study in ego-network groups. Both egos and their alters completed online surveys about their exercise habits. In addition, egos completed anthropometric measurements of BMI, fat percentage, and fat mass by bioimpedance.
From October 2009 to May 2010, flyers, emails, and Web advertisements yielded 335 volunteers who were screened. Rolling recruitment resulted in enrollment of 142 qualified participants in 54 ego-network groups, which were randomly assigned to a study condition. The final analytic sample included 87 individuals from 41 groups. Data were collected from December 2009 to August 2010, and data analysis was completed in 2011. Overall, the participants were given access to the intervention for 10-13 weeks. Statistical analysis suggested an increase in self-reported exercise frequency (mean days per week) from baseline (2.57, SD 1.92) to first FU (3.21, SD 1.74) in both conditions. Stronger effects were seen in the condition where Diary+Game was played first, especially in network groups with larger age variation between the alters and egos. Overall, the decrease in egos’ BMI was statistically significant from baseline to first FU, with greater decrease for those in the Diary+Game first condition (-0.26 vs -0.16 in the Diary first condition).
The Wellness Partners program increased physical activity among participants and resulted in health benefits among the egos. Web-based diary interventions designed with social gaming features hold potential to promote active lifestyles for middle-age adults and people in their social networks.
physical activity; social networking; diary; game; Web-based intervention; behavior change intervention
The aim of this study is to present the development of the Meanings of Eating Index (MEI) in a diverse sample of children. Exploratory factor analysis was performed on MEI items. Factors with eigenvalues above 1.0 were retained. Items that loaded on multiple factors or with item-total correlations below 0.50 were discarded. A 24-item, 5-factor scale comprised the final MEI. Personal Negative Emotions and Disturbed Eating were positively associated with frequency of high calorie snack food intake (r=0.21, p<0.05; r=0.33, p<0.01), Personal Well Being was positively associated with eating vegetables more frequently (r=0.20; p<0.05). Eating on Behalf of Others was negatively associated with frequency of vegetable intake (r=-.20; p<0.05). Pleasure Eating was not associated with dietary intake. The MEI shows promise as a tool for understanding the affective determinants of dietary intake in minority youth.
Eating behavior; Minority; Children; Latino
A brief motivational interviewing (MI) intervention may be a viable adjunct to school-based substance abuse prevention programs. This article describes the development and implementation of a brief MI intervention with 573 adolescents (mean age 16.8; 40.3% female, 68% Latino) enrolled in eight continuation high schools in Southern California. Study participants were assigned to the MI condition in a randomized controlled trial of Project Toward No Drug Abuse. Data are provided on dosage, topics discussed, and quality of MI determined with the Motivational Interviewing Skill Code (MISC). Results suggest that the protocol was feasible and implemented with adequate fidelity. The study’s limitations are noted.
adolescent; motivational interviewing; substance use; prevention; intervention; telephone; school-based; booster
This study aimed to test the effects of a circuit training (CT; aerobic + strength training) program, with and without motivational interviewing (MI) behavioral therapy, on reducing adiposity and type 2 diabetes risk factors in Latina teenagers.
Thirty-eight Latina adolescents (15.8 ± 1.1 yr) who are overweight/obese were randomly assigned to control (C; n = 12), CT (n = 14), or CT + MI (n = 12). The CT classes were held twice a week (60–90 min) for 16 wk. The CT + MI group also received individual or group MI sessions every other week. The following were measured before and after intervention: strength by one-repetition maximum; cardiorespiratory fitness (V̇O2max) by submaximal treadmill test; physical activity by accelerometry; dietary intake by records; height, weight, waist circumference; total body composition by dual-energy x-ray absorptiometry; visceral adipose tissue, subcutaneous adipose tissue, and hepatic fat fraction by magnetic resonance imaging; and glucose/insulin indices by fasting blood draw. Across-intervention group effects were tested using repeated-measures ANOVA with post hoc pairwise comparisons.
CT and CT + MI participants, compared with controls, significantly increased fitness (+16% and +15% vs −6%, P = 0.03) and leg press (+40% vs +20%, P = 0.007). Compared with controls, CT participants also decreased waist circumference (−3% vs +3%; P < 0.001), subcutaneous adipose tissue (−10% vs 8%, P = 0.04), visceral adipose tissue (−10% vs +6%, P = 0.05), fasting insulin (−24% vs +6%, P = 0.03), and insulin resistance (−21% vs −4%, P = 0.05).
CT may be an effective starter program to reduce fat depots and improve insulin resistance in Latino youth who are overweight/obese, whereas the additional MI therapy showed no additive effect on these health outcomes.
VISCERAL FAT; CIRCUIT TRAINING INTERVENTION; OVERWEIGHT LATINA ADOLESCENTS; FASTING INSULIN AND INSULIN RESISTANCE; MOTIVATIONAL INTERVIEWING
Minority girls are disproportionately affected by overweight and obesity. The independent effects of physical activity (PA), sedentary behavior (SB), and diet are not well understood.
This study examined the individual influences of PA, SB and diet on fat mass in Latina and African American (AA) girls, aged 8–11.
Baseline data from a longitudinal cohort study in minority girls is presented. Multiple linear regression analysis assessed the effects of PA, SB, and energy intake on fat mass, adjusting for lean mass, age, Tanner stage and ethnicity.
Participants were 53 Latina and AA girls (77% Latina; Mage=9.8 ± .9; MBMI%=80.8 ± 23.1). Moderate-to-vigorous physical activity (MVPA) by accelerometry (β= −.13, P<.01) and lean mass(β=.69, P<.001) were associated with fat mass (Model R2=.63; P<.0001). MVPA by 3-day-physical-activity-recall (β=−.04, P=.01) and lean mass (β=.75, P<.001) were associated with fat mass (Model R2=.61; P<.0001). SB and energy intake were not associated with fat mass in any model.
Using both objective and subjective measures of PA, MVPA, but not SB or diet, was associated with higher fat mass in Latina and AA girls, independent of lean mass, age, Tanner stage, and ethnicity. Prospective studies are needed to clarify the differential impact of diet and activity levels on adiposity in this population. (Ethn Dis. 2011;21(4):458–461)
Physical Activity; Overweight; Obesity; Latina; African American; Girls
To investigate the impact of worries on weight concerns and emotional eating and body mass index (BMI) percentile in an ethnically diverse sample of female youth.
This study uses baseline and follow-up data from a brief school-based physical activity intervention trial in minority female youth. Partial correlations adjusted for intervention status, age, and ethnicity were used to assess the relationship among emotional eating, weight concerns, and BMI percentile at follow-up. Multi-level modeling was used to analyze the relationships between baseline worries and follow-up emotional eating, weight concerns, and BMI percentile. Additional analysis assessed whether emotional eating mediated and/or moderated the relationship between baseline worries and follow-up BMI. Data were analyzed using SAS v9.1.
The sample consisted of 404 minority females (67.1% Latina; mean age 12.5±0.6; 60.6% normal weight). Weight concerns were positively correlated with emotional eating and BMI percentile (p< 0.001 for both). Baseline worries significantly predicted emotional eating (p= 0.027) and weight concerns (p< 0.001) but not BMI percentile (p= 0.183) at follow-up. Emotional eating did not mediate the relationship between baseline worries and follow-up BMI percentile; however it did moderate the relationship between baseline worries and follow-up BMI percentile (p= 0.003).
Worries were associated with psychosocial variables but not BMI percentile in this sample. Reducing worries in those with high emotional eating scores may influence future weight gain in Latina females.
psychosocial; minority; youth; BMI; weight concerns; emotional eating; mediation; moderation
The purpose of this study was to examine ethnic differences in the metabolic responses to a 16-week intervention designed to improve insulin sensitivity (SI), adiposity, and inflammation in obese African-American and Latino adolescents. A total of 100 participants (African Americans: n = 48, Latino: n = 52; age: 15.4 ± 1.1 years, BMI percentile: 97.3 ± 3.3) were randomly assigned to interventions: control (C; n = 30), nutrition (N; n = 39, 1×/week focused on decreasing sugar and increasing fiber intake), or nutrition + strength training (N+ST; n = 31, 2×/week). The following were measured at pre- and postintervention: strength, dietary intake, body composition (dual-energy X-ray absorptiometry/magnetic resonance imaging) and glucose/insulin indexes (oral glucose tolerance test (OGTT)/intravenous glucose tolerance test (IVGTT)) and inflammatory markers. Overall, N compared to C and N+ST reported significant improvements in SI (+16.5% vs. −32.3% vs. −6.9% respectively, P < 0.01) and disposition index (DI: +15.5% vs. −14.2% vs. −13.7% respectively, P < 0.01). N+ST compared to C and N reported significant reductions in hepatic fat fraction (HFF: −27.3% vs. −4.3% vs. 0% respectively, P < 0.01). Compared to N, N+ST reported reductions in plasminogen activator inhibitor-1 (PAI-1) (−38.3% vs. +1.0%, P < 0.01) and resistin (−18.7% vs. +11.3%, P = 0.02). There were no intervention effects for all other measures of adiposity or inflammation. Significant intervention by ethnicity interactions were found for African Americans in the N group who reported increases in total fat mass, 2-h glucose and glucose incremental areas under the curve (IAUC) compared to Latinos (P’s < 0.05). These interventions yielded differential effects with N reporting favorable improvements in SI and DI and N+ST reporting marked reductions in HFF and inflammation. Both ethnic groups had significant improvements in metabolic health; however some improvements were not seen in African Americans.
To examine the relationship of fasting indicators of insulin sensitivity with a more invasive measure of insulin sensitivity (frequently sampled intravenous glucose tolerance test [FSIVGTT]) and the effect of Tanner stage and ethnicity on that relationship.
RESEARCH DESIGN AND METHODS
Data were analyzed from 149 overweight girls (97 Hispanic and 52 African American) who were either in the early stages of maturation defined by Tanner stages 1 or 2 (52 Hispanic and 18 African American) or in the later stages of maturation defined by Tanner stages 4 and 5 (45 Hispanic and 34 African American). Fasting indicators of insulin sensitivity (IS) included fasting insulin and glucose and the homeostasis model assessment of insulin resistance (HOMA-IR). IS was derived from an FSIVGTT with minimal modeling.
In Tanner stages 1 and 2, all fasting indicators were significantly associated with IS: (fasting insulin: r = −0.67, P < 0.01; HOMA: r = −0.66, P < 0.01) with no significant influence of ethnicity on these relationships. In Tanner stages 4 and 5, however, all fasting indicators were associated with IS in African American girls (fasting insulin: r = −0.55, P < 0.01; HOMA: r = −0.47, P < 0.01), but none of the indicators were significantly associated with IS in Hispanic girls.
Fasting indicators were reflective of IS for girls in Tanner stages 1 and 2, regardless of ethnicity and may provide a clinical measure of future risk for type 2 diabetes. In the latter stages of maturation, however, more invasive measures are warranted to adequately determine IS in clinical practice.
Childhood obesity has become an epidemic on a worldwide scale. This article gives an overview of the progress made in childhood and adolescent obesity research in the last decade, with a particular emphasis on the transdisciplinary and complex nature of the problem. The following topics are addressed: 1) current definitions of childhood and adolescent overweight and obesity; 2) demography of childhood and adolescent obesity both in the US and globally; 3) current topics in the physiology of fat and obesity; 4) psychosocial correlates of childhood and adolescent overweight and obesity; 5) the three major obesity-related behaviors, i.e. dietary intake, physical activity and sleep; 6) genes components of childhood and adolescent obesity; 7) environment and childhood and adolescent obesity; and 8) progress in interventions to prevent and treat childhood obesity. The article concludes with recommendations for future research, including the need for large-scale, high dose and long-term interventions that take into account the complex nature of the problem.
Overweight is related to higher levels of C-reactive protein (CRP) and leptin, which have been independently associated with increased risk for diabetes, cardiovascular disease, and the metabolic syndrome. Elevated CRP may trigger leptin resistance by inhibiting the binding of leptin to its receptors. We cross-sectionally examined the relationship between CRP, leptin, BMI z-score, percent body fat (%BF) assessed by air plethysmography (BodPod), and insulin sensitivity (SI) and acute insulin response (AIRg) measured by intravenous glucose tolerance test in 51 Latina and African-American females (77% Latina), mean age 9.2 (±0.9) years, at either Tanner Pubertal Stage (TPS) 1 (n = 25) or TPS 2 (n = 26). Females at TPS 2 had higher BMI z-scores, %BF (23% ± 10.1 vs. 30% ± 10.0, P = 0.02), AIRg (976.7 ± 735.2 vs. 1555.3 ± 1,223 µIU/ml, P = 0.05), fasting insulin (11.0 ± 10.8 vs. 17.2 ± 13.6 µlU/ml, P = 0.00) and leptin levels (11.0 ± 7.1 vs. 19.6 ± 10.9 ng/ml, P < 0.001) than those at TPS 1. There were no ethnic differences in any of the measured variables. CRP was positively correlated with BMI z-score (P = 0.001), %BF (P = 0.006), fasting insulin and AIRg (P = 0.02), and fasting leptin (P = 0.00), and negatively correlated with SI (P = 0.05). A linear regression model showed that CRP independently explained 10% (P = 0.00) of the variance in leptin after adjusting %BF, TPS, ethnicity, habitual physical activity and SI. Hence, low-grade inflammation may contribute to prolonged leptin exposure and leptin resistance, even in healthy children.
Purpose: Compulsive Internet Use (CIU) has increasingly become an area of research among process addictions. Largely based on data from cross-sectional studies, a positive association between CIU and substance use has previously been reported. This study presents gender and country-specific longitudinal findings on the relationships between CIU and substance use. Methods: Data were drawn from youth attending non-conventional high schools, recruited into two similarly implemented trials conducted in China and the USA. The Chinese sample included 1,761 students (49% male); the US sample included 1,182 students (57% male) with over half (65%) of the US youth being of Hispanic ethnicity. Path analyses were applied to detect the concurrent and predictive relationships between baseline and one-year follow-up measures of CIU level, 30-day cigarette smoking, and 30-day binge drinking. Results: (1) CIU was not positively related with substance use at baseline. (2) There was a positive predictive relationship between baseline CIU and change in substance use among female, but not male students. (3) Relationships between concurrent changes in CIU and substance use were also found among female, but not male students. (4) Baseline substance use did not predict an increase in CIU from baseline to 1-year follow-up. Conclusions: While CIU was found to be related to substance use, the relationship was not consistently positive. More longitudinal studies with better measures for Internet Addiction are needed to ascertain the detailed relationship between Internet addiction and substance use.
compulsive internet use; internet addiction; youth; cigarette smoking; binge drinking; addiction syndrome; addiction specificity
To investigate associations of overweight status and perception with trajectories of psychological distress in adolescents.
Longitudinal data for 6,970 Chinese adolescents were included. The multivariate Curve-of-Factor Latent Growth Curve Models were adopted to examine trajectories of psychological distress symptoms and associations with overweight status and perception.
After controlling for actual overweight status, psychological distress symptoms were weakly but significantly associated with overweight perception (γ=0.08 for boys and γ=0.10 for girls, P<0.05) and misperception (γ=0.06 for boys and γ=0.09 for girls, P<0.05).
Our findings help understanding associations of overweight perception and psychological well being of adolescents.
weight perception; Chinese adolescents; psychological distress
This study examined associations between sleep onset latency and emotional eating in a minority sample of children. A cross-sectional school-based study of sleep, psychological constructs, diet and physical activity was conducted in 6 public and private schools in Los Angeles County. An ethnically diverse sample of 356 third through fifth graders completed confidential self-report surveys. Multilevel regression (MLM) analyses were conducted to study associations while controlling for gender, ethnicity, and the random effect of school. Girls made up 57% of the total sample, which was predominantly Latino (42.6%), followed by African Americans (21.6%) and Asians (19.2%). MLM revealed that there were significant associations between sleep onset latency and emotional eating (p=.030), depressive symptomology (p<.0001) and trait anxiety (p<.0001). Sobel's test for mediation showed that trait anxiety (p=.011) but not depressive symptomology (p=.141) was a mediator of the relationship between sleep onset latency and emotional eating. Thereby providing a mechanism through which sleep onset latency is related to emotional eating. These findings suggest that sleep onset latency is associated with increased anxiety, depressive symptoms, and emotional eating. Although causal inferences cannot be drawn from this cross-sectional data, future studies should examine the possibility that problems falling asleep could lead to emotional dysregulation that in turn leads to emotional eating. Emotional eating may be one avenue by which sleep disturbances lead to overweight and obesity.
anxiety; depression; sleep onset latency; emotional eating; mediation
A genome-wide study of adults identified a variant of PNPLA3 (rs738409) associated with ∼twofold higher liver fat. The purpose of this study was to examine the influence of PNPLA3 genotype on liver fat and other related metabolic outcomes in obese Hispanic children and adolescents.
RESEARCH DESIGN AND METHODS
Three hundred and twenty-seven Hispanics aged 8–18 years were genotyped for rs738409. One hundred and eighty-eight subjects had measures of visceral (VAT) and subcutaneous (SAT) adipose tissue volume and hepatic (HFF) and pancreatic (PFF) fat fraction by magnetic resonance imaging. One hundred and thirty-nine subjects did not have HFF measures but had extensive measures of insulin sensitivity and fasting lipids.
Liver fat in GG subjects was 1.7 and 2.4 times higher than GC and CC (11.1 ± 0.8% in GG vs. 6.6 ± 0.7% in GC and 4.7 ± 0.9% in CC; P < 0.0001), and this effect was observed even in the youngest children (8–10 years of age). The variant was not associated with VAT, SAT, PFF, or insulin sensitivity or other glucose/insulin indexes. However, Hispanic children carrying the GG genotype had significantly lower HDL cholesterol (40.9 ± 10.9 in CC vs. 37.0 ± 8.3 in CG vs. 35.7 ± 7.4 in GG; P = 0.03) and a tendency toward lower free fatty acid levels (P = 0.06).
These results provide new evidence that the effect of the PNPLA3 variant is apparent in Hispanic children and adolescents, is unique to fat deposition in liver as compared with other ectopic depots examined, and is associated with lower HDL cholesterol.
Little is known about the co-occurrence of health risk behaviors in childhood that may signal later addictive behavior. Using a survey, this study evaluated high calorie, low nutrient HCLN intake and video gaming behaviors in 964 fourth grade children over 18 months, with stress, sensation-seeking, inhibitory control, grades, perceived safety of environment, and demographic variables as predictors. SEM and growth curve analyses supported a co-occurrence model with some support for addiction specificity. Male gender, free/reduced lunch, low perceived safety and low inhibitory control independently predicted both gaming and HCLN intake. Ethnicity and low stress predicted HCLN. The findings raise questions about whether living in some impoverished neighborhoods may contribute to social isolation characterized by staying indoors, and HCLN intake and video gaming as compensatory behaviors. Future prevention programs could include skills training for inhibitory control, combined with changes in the built environment that increase safety, e.g., implementing Safe Routes to School Programs.
eating; video gaming; children; addictive behavior
Stress and the cortisol awakening response (CAR) have been independently linked to increases in abdominal fat depots. This cross-sectional study examined the CAR as a moderator of the association between stress, visceral adipose tissue (VAT), and subcutaneous abdominal adipose tissue (SAT) in a sample (N = 23) of female peripubertal Hispanic girls aged from 8 to 11. The study included: (i) monitored salivary cortisol collection, (ii) VAT and SAT obtained by multislice magnetic resonance imaging, and (iii) a stressful life events checklist with four domain-specific subscales: peer, family, personal, and school. Regression analysis indicated an interaction of school-related life events and CAR on VAT and SAT, with greater numbers of school-related events being related to greater VAT and SAT for girls with high CAR, but no association with VAT or SAT for girls with low CAR. Similar to job stress in adults, school-related stress in children may contribute to central adiposity, especially for girls with high CAR.
This paper describes an experimental study in estimating energy expenditure from treadmill walking using a single hip-mounted triaxial inertial sensor comprised of a triaxial accelerometer and a triaxial gyroscope. Typical physical activity characterization using accelerometer generated counts suffers from two drawbacks - imprecison (due to proprietary counts) and incompleteness (due to incomplete movement description). We address these problems in the context of steady state walking by directly estimating energy expenditure with data from a hip-mounted inertial sensor. We represent the cyclic nature of walking with a Fourier transform of sensor streams and show how one can map this representation to energy expenditure (as measured by V O2 consumption, mL/min) using three regression techniques - Least Squares Regression (LSR), Bayesian Linear Regression (BLR) and Gaussian Process Regression (GPR). We perform a comparative analysis of the accuracy of sensor streams in predicting energy expenditure (measured by RMS prediction accuracy). Triaxial information is more accurate than uniaxial information. LSR based approaches are prone to outlier sensitivity and overfitting. Gyroscopic information showed equivalent if not better prediction accuracy as compared to accelerometers. Combining accelerometer and gyroscopic information provided better accuracy than using either sensor alone. We also analyze the best algorithmic approach among linear and nonlinear methods as measured by RMS prediction accuracy and run time. Nonlinear regression methods showed better prediction accuracy but required an order of magnitude of run time. This paper emphasizes the role of probabilistic techniques in conjunction with joint modeling of triaxial accelerations and rotational rates to improve energy expenditure prediction for steady-state treadmill walking.
Accelerometer; Energy expenditure; Gyroscope; Treadmill walking