Background: To elucidate the populations and conditions where screen-based sedentary behaviors (SB) and internalizing symptoms are coupled, this review synthesized the evidence for factors that may moderate the associations between screen-based SB, depressive symptoms, and anxiety symptoms among youth. Methods: Two independent researchers conducted a systematic literature search of the Medline, psycINFO, and Scopus electronic databases in late 2018 for observational studies assessing moderators of the association between screen-based SB and depressive and anxiety symptoms. Studies among children and adolescents were eligible if moderation was assessed by statistical test (interaction) or stratification; and a narrative synthesis of eligible studies was conducted in accordance with PRISMA guidelines. Results: Seventy empirical studies (46 cross-sectional, 19 longitudinal, and 5 both) of 13 different moderating variables of screen-based SB-internalizing symptom associations met the eligibility criteria. Of these, 40 studies were of depressive symptoms, 2 were of anxiety symptoms, and 28 studies assessed symptoms of both. The most consistent evidence of moderation was for screen-type, such that TV viewing was not as strongly associated with internalizing symptoms compared to other forms of screen-based SB. There was also inconsistent evidence for physical activity buffering screen-based SB-internalizing symptom associations and for female sex amplifying screen-based SB-internalizing symptom associations. In general, the body of evidence for anxiety symptoms was more limited than that for depressive symptoms, and were therefore more inconsistent. Conclusions: Screen-type, physical activity, and sex may influence the magnitude of screen-based SB-internalizing symptom coupling; highlighting potential sources of heterogeneity of screen-based SB-internalizing symptom associations. Additional studies aimed at understanding potential mechanistic explanations for the above moderators are needed prior to the development of tailored intervention strategies designed to decouple screen-based SB and internalizing symptoms among youth.

Objective: Physical activity (PA) promotes weight maintenance, potentially because of its beneficial effects on feeding behavior regulation via diminished food cue reactivity within brain reward regions. This study examined how levels of PA and sedentary behavior (SB) relate to brain responses to food cues.Methods: Participants (22 lean, 18 with obesity) completed three to five PA recalls over 2 months. Average minutes per day of moderate to vigorous PA (MVPA) and SB were calculated. Participants completed a functional magnetic resonance imaging session, viewing food and nonfood images following glucose ingestion. Region of interest (ROI) analysis examined associations between MVPA and brain percent signal change in response to food versus nonfood images, controlling for obesity and sex. Secondary analysis examined associations between SB and brain responses to food cues.Results: Greater MVPA was associated with decreased food cue reactivity after glucose across brain ROIs (β = −0.00057, P = 0.005), controlling for obesity and sex. Greater SB was associated with increased food cue reactivity after glucose across brain ROIs in unadjusted analyses (β = 0.00041, P = 0.026).Conclusions: PA may have beneficial effects on brain regulation of feeding behavior after caloric intake in lean individuals and individuals with obesity.

Background: Childhood obesity prevention interventions routinely focus on changing maternal parenting practices. Failure to assess how fathers’ weight-related (ie, diet and physical activity) parenting practices contribute to children’s energy balance behaviors limits the understanding of their paternal role within the family. Examining the independent and interacting effects of fathers’ and mothers’ weight-related parenting practices on children’s diet and physical activity addresses this important research gap. Objective: This study used ecological momentary assessment (EMA) to investigate the within-subject and between-subject independent and interactive effects of maternal and paternal encouragement to eat and preparation of fruits and vegetables (F/V) and encouragement of and taking their child to be physically active on their child’s self-reported F/V intake and physical activity engagement. Methods: Participants included mother-father-child triads (n=22 triads, n=205-213 prompts/occasions) in the Mothers and Their Children’s Health Study and the University of Southern California Fathers Study. Simultaneously, mothers and fathers (agesmean 44.2 years, SD 5.6, and 45.2 years, SD 8.1, respectively), and their children (agemean 12.0 years, SD 0.7) completed up to 8 randomly prompted EMA surveys per day on separate smartphones for 7 days. At each prompt, mothers and fathers each reported whether they did the following in the past 2 hours: (1) encouraged their child to eat F/V, (2) prepared F/V for their child, (3) encouraged their child to be physically active, or (4) took their child to be physically active. Children self-reported whether they consumed F/V or were physically active in the past 2 hours. Results: Results from Bayesian multilevel logistic models (all in log-odd units) indicated that at the within-subject level, greater maternal encouragement (β=2.28, 95% CI 0.08 to 5.68) of eating F/V was associated with greater child report of eating F/V, but paternal encouragement (β=1.50, 95% CI –0.83 to 4.52) showed no effects above and beyond maternal encouragement. Additionally, greater than usual paternal encouragement (β=2.28, 95% CI 0.08 to 5.54) and maternal encouragement (β=2.94, 95% CI 0.36 to 6.69) of physical activity had significant independent effects and were associated with greater child report of physical activity. No other within-subject or between-subject associations nor interactive effects were significant. Conclusions: Findings from this study suggest that fathers play a role in supporting their children’s physical activity but not their intake of F/V. Future EMA studies should recruit larger samples to evaluate the independent and interacting roles of mothers’ and fathers’ weight-related parenting practices on child’s obesogenic behaviors.