Covariability in Diet and Physical Activity in African-American Girls

Compliance with a physical activity guideline among junior high school students

BACKGROUND

There were no nationwide moderate- to vigorous-intensity physical activity (MVPA) data relating to Japanese adolescents. This study assessed compliance with an MVPA guideline by adolescents, using a random sampling survey in Japan. The factors associated with compliance with the guideline were also examined.

METHODS

Participants were first- to third-grade Japanese junior high school students (307 boys and 255 girls). We analyzed data from the National Sports-Life Survey of Teens 2019, which used the Japanese version of physical activity (PA) questions in the World Health Organization Health Behavior in School-aged Children survey and potential correlates of MVPA.

RESULTS

Compliance with the PA guideline by the World Health Organization for Japanese students was 19.0% (95% confidence interval (CI), 15.8-22.3). The compliance of boys was significantly higher than that of girls (23.1%; 95% CI, 18.4-27.8; vs 14.1%; 95% CI, 9.8-18.4). The odds of meeting the PA guideline were significantly higher for boys in the second grade than boys in the first grade (odds ratio (OR) 1.78; 95% CI, 1.02-3.09), liking PA (for all: OR: 2.97; 95% CI, 1.32-6.69; for girls: OR: 2.99; 95% CI, 1.01-8.81), and sports participation (for all: OR: 4.77; 95% CI, 2.32-9.80; for boys: OR: 6.00; 95% CI, 1.81-19.89; for girls: OR: 4.08; 95% CI, 1.63-10.21).

CONCLUSIONS

The results suggest that more than 80% of junior high school students were insufficiently physically active in Japan. Preferences for PA and sports participation may be important correlates of sufficient PA.

Differences in the Association of Physical Activity and Children's Overweight and Obesity Status Among the Major Racial and Ethnic Groups of U.S. Children

OBJECTIVE

To examine the relationship of exercise with overweight and obesity among an ethnically diverse sample of U.S. children.

METHOD

Data from the 2011-2012 National Survey of Children's Health were analyzed to examine the relationship of daily exercise with children's weight status. Propensity score covariate adjustment and multivariate logistic regression with survey weights were used to control for child, home, and community characteristics.

RESULTS

Approximately 22% of all children ages 10 to 17 years engaged in daily exercise for at least 20 minutes. In the adjusted model for the entire sample, daily exercise was associated with children having a lower likelihood of being overweight or obese (odds ratio = 0.79; 95% confidence interval = 0.68-0.91). In a stratified analysis of the major racial and ethnic groups, however, while White children who exercised daily were found to have a lower odds of being overweight or obese (odds ratio = 0.70; 95% confidence interval = 0.60-0.82), this relationship was not found for most minority children.

CONCLUSIONS

Racial and ethnic minority children were not found to have the same weight status relationship with exercising daily. These findings suggest that some population-average exercise recommendations may not be as applicable to minority children.

Breakfast consumption and physical activity in adolescents: daily associations and hourly patterns

BACKGROUND

The association between breakfast consumption and physical activity (PA) is inconclusive.

OBJECTIVE

We aimed to investigate daily associations and hourly patterns of PA and breakfast consumption in British adolescents.

DESIGN

Daily PA [accelerometry-derived moderate and vigorous physical activity (MVPA)] and breakfast consumption (diet diary) were measured simultaneously over 4 d in 860 adolescents (boys: 43.4%; mean ± SD age: 14.5 ± 0.5 y). Associations between MVPA and breakfast consumption were assessed by using a multilevel mixed-effects logistic regression separately by sex and for weekends and weekdays. Hourly patterns of MVPA by breakfast consumption status were displayed graphically, and differences were tested by using ANOVA. Multilevel linear regression was used to investigate differences in log MVPA on days when 570 inconsistent breakfast consumers ate or skipped breakfast.

RESULTS

On weekends, boys and girls with higher MVPA were more likely to eat breakfast [OR (95% CI): boys, 1.78 (1.30, 2.45) (P < 0.001); girls, 2.30 (1.66, 3.08) (P < 0.001)] when adjusted for socioeconomic status, percentage of body fat, and total energy intake. Peak hourly MVPA differed for breakfast consumers compared with nonconsumers on weekends (P < 0.001). Inconsistent breakfast consumers did more MVPA on days when they ate breakfast [exponentiated β coefficients (95% CIs): 1.2 (1.0, 1.5) on weekdays and 1.4 (1.1, 1.8) on weekends for boys and 1.6 (1.3, 2.1) on weekends for girls; all P < 0.03].

CONCLUSIONS

Eating breakfast was associated with higher MVPA on weekends. The time of peak MVPA differed between breakfast consumers and nonconsumers on weekends. Breakfast consumption at weekends is worth additional investigation to potentially inform PA promotion in adolescents.

Physical Activity, Sedentary Behavior, and Dietary Patterns among Children

Energy balance-related behavioral patterns find their origin in early childhood. The current paper provides an overview of studies that have examined such behavioral patterns, i.e., the clustering of dietary behaviors, physical activity, and/or sedentary behavior. The paper discusses the importance of examining energy balance-related behavioral patterns in children, outlines methods to examine these patterns, and provides examples of patterns that have been found (e.g., the universal sedentary-snacking and healthy intake patterns, as well as more unique or local patterns), child and parental characteristics predicting such patterns (e.g., child gender and maternal educational level), and the relationship of these patterns with overweight and related measures.

Breakfast consumption and physical activity in British adolescents

Studies show an inverse relationship between breakfast frequency and weight gain. This may reflect poor eating habits generally and associated low physical activity (PA) or direct impacts of breakfast on mechanisms leading to lethargy and reduced PA. The relationship between breakfast frequency and PA is inconclusive. We aimed to determine whether breakfast frequency is associated with PA levels in British adolescents independent of body composition and socio-economic status (SES). Habitual breakfast frequency (self-report questionnaire) was assessed in 877 adolescents (43% male, age 14·5 (SD 0·5) years old). PA was measured over 5 d (accelerometry, average counts/ min; cpm). Associations between daily PA and breakfast frequency were assessed using linear regression adjusted for body fat percentage and SES. Effect modification by sex and associations with PA during the morning (06.00-12.00 hours) were explored. For boys, there were no significant associations between breakfast frequency and PA. For girls, less frequent breakfast consumption was significantly associated with lower PA (cpm) during the morning (occasional v. frequent b - 6·1 (95% CI - 11·1, -1·1), P = 0·017) when adjusted for body fat percentage and SES. There were no associations between PA and breakfast consumption over the whole day; however, for girls, less frequent breakfast consumption may be associated with lower PA levels during the morning, suggesting that breakfast consumption should perhaps be taken into consideration when aiming to promote PA in adolescent girls.

Boy Scout 5-a-Day Badge: outcome results of a troop and Internet intervention

OBJECTIVES

The effects of a Boy Scout Five-A-Day Badge program on fruit juice (FJ) and low-fat vegetable (LV) consumption were evaluated using a two-condition (treatment, active-attention-placebo-control) group randomized trial, with three data collection periods (baseline, immediate post, 6-month post).

METHODS

Forty-two Boy Scout troops (n=473, 10- to 14-year-old Scouts) in Houston, TX, were randomly assigned to condition. The 9-week program included approximately 30 min of weekly troop time, plus approximately 25 min of weekly Internet programming. The intervention was delivered in two waves (Spring and Fall). Data were collected in 2003-2004, and analyses were completed in 2008. Main outcomes were FJ and LV consumption (validated food frequency questionnaire). FV self-efficacy, preferences, and home availability were also measured.

RESULTS

Significant increases in FJ consumption (p=.003), FJ home availability (p=.009), and LV self-efficacy (p=.004) were observed among the intervention group immediately following the intervention but were not maintained 6 months later.

CONCLUSION

A Boy Scout troop-plus-Internet intervention promoting FJ and LV consumption resulted in short-term changes in FJ consumption among U.S. Boy Scouts. Future research should investigate ways to extend these results to LV and maintain the increases over time.

Secular and seasonal trends in obesity in Chilean preschool children, 1996-2004

OBJECTIVES

Chile is a unique example of the nutrition transition, with improvements in undernutrition and subsequent rapid increases in obesity occurring at a rate much faster than in other countries. This study aims to describe the cross-sectional obesity trends in Chilean preschool children from 1996 to 2004.

MATERIALS AND METHODS

Anthropometric measurements from preschool children (ages 2-5) registered in the Junta Nacional de Jardines Infantiles program from 1996 to 2004 were analysed. The weight-for-height z score using the World Health Organization 1977/1985 reference curves for age, sex, height, and weight were defined to estimate overweight and obesity. The overall trends in obesity were described for each study year and generalized estimating equation models were used to describe trends in obesity after adjusting for the correlated nature of repeated measurements in individual children in consecutive years.

RESULTS

The prevalence of obese and overweight children has remained constant in both boys and girls during the past 9 years; however, after adjustment for repeated measurements in individual children, the odds of obesity increased by 30% each year (odds ratio [OR] 1.28, 95% confidence interval [CI] 1.27-1.31, P < 0.001). Furthermore, the odds of obesity were significantly greater in both August and November compared with March.

CONCLUSIONS

The prevalence of obesity in Chilean preschool children continues to be a major public health concern, and cross-sectional trends may underestimate the magnitude of the problem.

Covariation of adolescent physical activity and dietary behaviors over 12 months

PURPOSE

This study examined covariation among changes in dietary, physical activity, and sedentary behaviors over 12 months among adolescents participating in a health behavior intervention. Evidence of covariation among behaviors would suggest multi-behavior interventions could have synergistic effects.

METHODS

Prospective analyses were conducted with baseline and 12-month assessments from a randomized controlled trial to promote improved diet, physical activity, and sedentary behaviors (experimental condition) or SUN protection behaviors (comparison condition). Participants were adolescent girls and boys (N = 878) aged 11-15 years on entry. The main outcomes were: diet, based on multiple 24-hour recalls (total fat, grams of fiber, servings of fruit and vegetables, total calories); average daily energy expenditure (kcals/kg) based on 7-day physical activity recall interviews; daily minutes of moderate-vigorous physical activity minutes from accelerometery; and self-reported daily hours of sedentary behavior.

RESULTS

Covariation was found between fat and calories (r = .16), fiber and calories (r = .53), fiber and fruit/vegetables (r = .53), calories and fruit/vegetables (r = .34), and fruit and vegetables and sedentary behavior (r = -.12) for the total sample (all p values < .01). The pattern of findings was similar for most subgroups defined by gender and study condition.

CONCLUSIONS

The strongest covariation was observed for diet variables that are inherently related (calories and fat, fiber, and fruit/vegetables). Little covariation was detected within or between other diet, physical activity and sedentary behavior domains suggesting that interventions to improve these behaviors in adolescents need to include specific program components for each target behavior of interest.

The association between changes in height and obesity in Chilean preschool children: 1996-2004

OBJECTIVES

To establish the association between changes in height and prevalence of obesity between 1996 and 2004 in Chilean preschool children.

RESEARCH METHODS AND PROCEDURES

Children registered in the Junta Nacional de Jardines Infantiles (JUNJI) preschool program were routinely measured three times a year and in consecutive years. Two indices [weight-for-height z-scores (WHZ) and BMI centiles] were used to define obesity. Height-for-age z-scores (HAZ) were used to define stature. Generalized estimating equations were used to describe the relationship between stature and obesity while controlling for repeated measurements in children.

RESULTS

The prevalence of obesity in Chilean preschool children has remained relatively constant over the past 9 years when either index is used. The prevalence of stunted (HAZ<or=2) children has decreased, while the proportion of children who are tall (HAZ>2) has increased. Using WHZ to define obesity, stunted children do not seem to be at increased risk of obesity when compared with children of normal height. Tall children were strongly protected from obesity when either criterion was used to define obesity.

DISCUSSION

The lack of association between stunting and obesity using WHZ>or=2 likely reflects the fact that Chile is in the post-transitional phase of the nutrition transition, and stunting is no longer a risk factor for obesity; however, the associations observed between stunting and BMI suggest that either WHZ or BMI, or both, are inaccurate criteria to define overweight.

CONCLUSIONS

There is a unique relationship between stature and obesity in preschool children that is different from that observed in older children in the same population.