Associations of adolescent lifestyle behaviors with body mass index within a nationally representative sample of US adolescents: a quantile regression analysis

Short sleep duration and adolescent health: does weekend catch-up sleep work and for whom?

OBJECTIVES

Despite evidence that sleep duration affects adolescent health, there remain important research gaps in the literature. Little is known about (1) whether the association between weekday sleep duration and health is confounded by unobserved individual heterogeneity and (2) the extent to which weekend catch-up sleep (WCS) duration moderates this association. This study addresses these gaps.

STUDY DESIGN

Using six waves of longitudinal data from the 2011-2016 Korean Children and Youth Panel Survey (N = 6633), this study examined the relationship between weekday sleep duration, WCS duration, and two measures of adolescent health, body mass index (BMI) and self-rated health (SRH).

METHODS

We estimated fixed effects models to account for individual-level heterogeneity.

RESULTS

Fixed effects estimates suggest that part of the associations between short sleep duration and adolescent health are confounded by unobserved individual heterogeneity (62% for BMI and 30% for poor SRH), although the associations remain statistically significant. Sleeping less than 6 h increased BMI by 0.203 and the probability of reporting poor SRH by about 2 percentage points. Controlling for individual heterogeneity, however, changed the sign of the WCS duration coefficient, suggesting that a longer WCS duration is positively associated with BMI (b = 0.021). No such patterns were found for SRH.

CONCLUSIONS

Short weekday sleep duration threatens adolescent health. WCS duration is protective only for those who are most sleep deprived.

Bidirectional relationships of physical activity and gross motor skills before and after summer break: Application of a cross-lagged panel model

BACKGROUND

Gross motor skills are postulated to have a bidirectional relationship with physical activity (PA); however, no study has tested this relationship before and after a summer break. The purpose of this study was to examine the bidirectional relationships between school PA and gross motor skills in children before and after a summer break.

METHODS

Participants were a sample of 440 children recruited from 3 low-income schools (age = 8.9 ± 1.2 years, mean ± SD). PA was assessed as average school-day step counts using Yamax DigiWalker pedometers (Yamasa Tokei Keiki, Tokyo, Japan) worn for 5 consecutive school days. Gross motor skills were assessed using the Test for Gross Motor Development, 3rd edition. Data were collected at 2 timepoints: at the end of spring semester (T1) and at the beginning of the subsequent fall semester (T2). An age- and body mass index-adjusted cross-lagged model was employed to relate T1 school step counts with T2 gross motor skills and T1 gross motor skills with T2 school step counts.

RESULTS

T1 gross motor skills significantly predicted T2 school step counts (β = 0.24, 95 % confidence interval (95%CI): 0.08-0.40, p = 0.003); however, T1 school step counts did not predict T2 gross motor skills (β = 0.04, 95%CI: -0.06 to 0.14, p = 0.445). The model explained 35.4% and 15.9% of the variances of T2 gross motor skills and T2 school step counts, respectively. Additional analyses indicated that these relationships were driven primarily by ball skills.

CONCLUSION

The relationship between gross motor skills and school PA was not bidirectional; however, higher gross motor skills, specifically ball skills, predicted higher school PA after a 3-month summer break.

Anthropometric Measurements, Sociodemographics, and Lifestyle Behaviors among Saudi Adolescents Living in Riyadh Relative to Sex and Activity Energy Expenditure: Findings from the Arab Teens Lifestyle Study 2 (ATLS-2)

The aim of the study was to examine the anthropometric measurements, sociodemographics, and lifestyle behaviors among Saudi adolescents relative to sex and physical activity (PA). A random cross-sectional survey conducted on Saudi adolescents from secondary schools in Riyadh, using a multistage stratified cluster sampling technique. Measurements included demographics, weight, height, waist circumference, PA, sedentary behaviors (SB), sleep duration, and dietary habits using a validated questionnaire. A total of 1262 adolescents (16.4 ± 0.95 years; 52.4% males) were studied. Overweight/obesity was more than 40%. Physical inactivity among adolescents was 53%, which indicates some improvement over the past years, especially among females. More than 80% of adolescents had over three hours/day of screen time, with no significant sex differences. Insufficient sleep was highly prevalent with gender differences. A large proportion of the participants did not consume daily breakfast (65.7%), vegetables (73.2%), fruits (84.2%), or milk/dairy products (62.4%), whereas significant proportions of the adolescents consumed sugar-sweetened drinks, fast food, French fries/potato chips, cake/donuts, and chocolates/candy on at least three days or more per week. It was concluded that non-daily intake of breakfast and vegetables was significantly associated with lower PA. The updated information can aid in effectively planning and implementing promotional programs toward improving the lifestyle behaviors of Saudi adolescent.

Videogame-related experiences among regular adolescent gamers

The objective of this study was to identify the videogame-related experiences expressed by regular adolescent gamers and to explore the socio-family factors related to these experiences. A cross-sectional observational and descriptive study was carried out with a convenience sample of regular Spanish videogamers between 16 and 18 years old. To measure the use of videogames for evasion and its negative consequences, the Questionnaire of Videogame-Related Experiences (Cuestionario de Experiencias Relacionadas con Videojuegos, CERV) was used and socio-family variables collected, evaluating their relationship with the results of the CERV. A total of 206 adolescents participated, 89.3% men [84.3-93.2] and 17.9% [12.9-23.9] allocating more than 35 hours a week to videogames. The CERV subscale related to the evasive use of videogames (max. = 24 points) obtained a mean value of 11.71 (SD = 3.52) and the mean value for the subscale related to the negative consequences (max. = 27 points) was 7.14 (SD = 3.33). A higher frequency of high values of evasive use (p = .038) and higher scores of this subscale (p = .02) were found in gamers without brothers or sisters. Higher scores and larger numbers of negative consequences were found in gamers who play more than 21 hours a week (p = .032). In conclusion, frequent use of videogames does not seem to be carried out with an evasive purpose, except in the case of absence of siblings. Frequent videogame use has only proven to carry a higher level of negative consequences when playing more than 21 hours a week. No other socio-family variables related to these subscales of the CERV have been identified.