Temporal relationship between insulin sensitivity and the pubertal decline in physical activity in peripubertal Hispanic and African American females

Associations of Mothers' and Children's Stress With Children's Device-Measured Physical Activity and Sedentary Behavior Trajectories Across 3 Years

BACKGROUND

Psychological stress has adverse effects on health-related behaviors, yet longitudinal research is lacking. Research examined how children's and mothers' perceived stress are associated with children's physical activity and sedentary behavior trajectories across 3 years.

METHODS

Mothers and their children (N = 186 dyads; 8-12 y at baseline, 57% Hispanic) completed 6 assessments across 3 years. Children and mothers self-reported perceived stress using the Stress in Children Scale and Perceived Stress Scale, respectively. Children's moderate to vigorous physical activity (MVPA) and sedentary behavior were assessed using accelerometers. Mixed models examined interactions of mothers' and children's perceived stress by time elapsed in the study on children's MVPA and sedentary behavior.

RESULTS

The perceived stress × time elapsed interactions were significant for children's MVPA and sedentary behavior (Ps < .05). Higher average perceived stress in mothers was associated with greater decreases in children's MVPA and increases in children's sedentary behavior. The child stress × time elapsed interactions was significant for children's MVPA (P < .05) but not sedentary behavior. Higher average perceived stress in children was associated with smaller decreases in children's MVPA.

CONCLUSION

Interventions to promote physical activity and reduce screen time in children should mitigate the effects of psychological stress, especially among mothers, on these behaviors.

Amidst the COVID-19 pandemic childhood obesity is still an epidemic-spotlight on obesity's multifactorial determinants

PURPOSE

Childhood obesity is a global epidemic and a chronic disease. Multifactorial determinants have long been linked with childhood obesity. These have been challenged with the onset of COVID-19 and the associated mitigation measures. The study aimed to re-highlight these determinants while exploring the effects of the ongoing COVID-19 pandemic on these pre-existing childhood obesity determinants, while providing evidence that may be beneficial for the post-COVID-19 recovery plan.

METHODS

A PubMed literature search (2016-2021) using the keywords, "childhood obesity", "gender", "sex", "obesity in youth", "obesity in adolescents", "COVID-19″ and "SARS-CoV2" was performed.

RESULTS

Genetic predisposition, biologically low leptin levels, certain cultural beliefs and socio-economic statuses, as well as exposure to an "obesogenic" environment were found to have a positive association with childhood obesity. Additionally, the onset of COVID-19 further aggravates the childhood obesity epidemic, increasing childrens' susceptibility to obesity and all associated consequential diseases.

DISCUSSION

A possible key to the control and prevention of the burden of childhood obesity, lies in dealing with its precursors and risk factors. Certain factors, including socio-cultural norms, cultural beliefs and geographical factors are amenable. COVID-19 further challenged these and it is evident that the childhood obesity epidemic is still a critical one. Encouraging preventative interventions, such as screening programs, public awareness and policies targeting the environment, amongst others, are recommended.

New Insights Into Causal Pathways Between the Pediatric Age-Related Physical Activity Decline and Loss of Control Eating: A Narrative Review and Proposed Conceptual Model

Research consistently suggests that loss of control (LOC) eating in children and adolescents is a key factor contributing to pediatric obesity and eating disorders. However, causes of pediatric LOC eating are yet unclear, and there is a lack of longitudinal research investigating the developmental processes contributing to LOC eating and related outcomes in youth. Physical activity is an understudied behavior that declines during middle childhood to adolescence and may exert an influence in the development of LOC eating via its impact on executive functioning. While physical activity levels and executive functioning have been linked to regulation of eating, no research has examined the mechanistic processes by which these domains may together impact LOC eating during childhood and adolescence. In the current narrative review, a model is proposed that suggests how physical activity and executive functioning influence LOC eating and related outcomes during childhood and adolescence. This model has the potential to influence future theoretical models of pediatric LOC eating and guide future prevention and intervention efforts.

The Roles of Physical Activity, Exercise, and Fitness in Promoting Resilience During Adolescence: Effects on Mental Well-Being and Brain Development

Adolescence is a critical yet vulnerable period for developing behaviors important for mental well-being. The existing literature suggests that physical activity (PA), exercise, and aerobic fitness promote well-being and reduce risk of mental health problems. In this review, we focus on PA, exercise, and fitness as modifiable resilience factors that may help promote self-regulation via strengthening of top-down control of bottom-up processes in the brain, thereby acting as a buffer against mental health problems during this period of vulnerability. First, we briefly review the link between PA, exercise, and aerobic fitness with mental well-being and reduced mental health problems in adolescence. Then we present how impairments in self-regulation, which involves top-down control to modulate bottom-up processes, are common across a wide range of mental health disorders. Finally, we use the extant neuroimaging literature to highlight how neural systems underlying top-down control continue to develop across adolescence, and propose that PA, exercise, and aerobic fitness may facilitate resilience through strengthening individual brain regions as well as large-scale neural circuits to improve emotional and behavioral regulation. Future neuroimaging studies assessing the effects of PA, exercise, and aerobic fitness at various developmental stages in each sex and studies considering the characteristics (e.g., frequency, intensity, type) and social context of PA and exercise are vital to better understand both macro- and microscale mechanisms by which these behaviors and attributes may facilitate mental health resilience during adolescent development.

Content validity and methodological considerations in ecological momentary assessment studies on physical activity and sedentary behaviour: a systematic review

Background

Ecological momentary assessment (EMA) is a method of collecting real-time data based on repeated measures and observations that take place in participant’s daily environment. EMA has many advantages over more traditional, retrospective questionnaires. However, EMA faces some challenges to reach its full potential. The aims of this systematic review are to (1) investigate whether and how content validity of the items (i.e. the specific questions that are part of a larger EMA questionnaire) used in EMA studies on physical activity and sedentary behaviour was assessed, and (2) provide an overview of important methodological considerations of EMA in measuring physical activity and sedentary behaviour.

Methods

Thirty papers (twenty unique studies) were systematically reviewed and variables were coded and analysed within the following 4 domains: (1) Content validity, (2) Sampling approach, (3) Data input modalities and (4) Degree of EMA completion.

Results

Only about half of the studies reported the specific items (n = 12) and the source of the items (n = 11). None of the studies specifically assessed the content validity of the items used. Only a minority (n = 5) of the studies reported any training, and one tested the comprehensibility of the EMA items. A wide variability was found in the design and methodology of the EMA. A minority of the studies (n = 7) reported a rationale for the used prompt frequency, time selection, and monitoring period. Retrospective assessment periods varied from ‘now’ to ‘in the last 3.5 hours’. In some studies there was a possibility to delay (n = 6) or deactivate (n = 10) the prompt, and some provided reminders after the first prompt (n = 9).

Conclusions

Almost no EMA studies reported the content validation of the items used. We recommend using the COSMIN checklist (COnsensus-based Standards for the selection of health Measurement INstruments) to report on the content validity of EMA items. Furthermore, as often no rationale was provided for several methodological decisions, the following three recommendations are made. First, provide a rationale for choosing the sampling modalities. Second, to ensure assessment ‘in the moment’, think carefully about the retrospective assessment period, reminders, and deactivation of the prompt. Third, as high completion rates are important for representativeness of the data and generalizability of the findings, report completion rates.

Trial registration

This review is registered in PROSPERO, the International prospective register of systematic reviews (registration number: CRD42017077996).

Age, Physical Activity Motivation and Perceived Stress in Minority Girls

BACKGROUND

Physical activity in childhood and adolescence helps support physical and emotional health.

PURPOSE

The study aimed to investigate if age was related to motivation for physical activity in minority girls, and whether the relationship may be potentially mediated by psychological or physiological stress.

METHODS

This cross-sectional observational study recruited Latino and African American girls ages 8 - 12 years (n = 79) in Tanner stage 1 or 2 via purposive sampling. Intrinsic motivation and perceived stress were measured by self-report survey; morning salivary cortisol samples were taken to calculate cortisol awakening response to estimate biological stress reactivity.

RESULTS

Increased age was related to higher intrinsic motivation to engage in physical activity. Lower perceived stress and lower awakening cortisol response were associated with higher intrinsic motivation. Bootstrapped mediation results indicated perceived stress may be a pathway through which age impacts intrinsic motivation for physical activity.

CONCLUSION

While motivation to engage in physical activity may increase with age, perceived stress may dampen this motivation, resulting in decreased physical activity. Interventions to help increase pre-adolescent girls' engagement in active behaviors may benefit from reducing children's perceptions of stress.

Is there a causal relationship between obesity and puberty?

The onset of puberty in adolescents and whether it is related to obesity is an ongoing topic for debate. Epidemiological cross-sectional and longitudinal studies show a shift towards earlier onset of puberty in girls who are obese; however, the situation is less clear in boys. Boys who are overweight seem to mature earlier, and boys who are obese mature later, than boys at a healthy weight. The underlying mechanisms are not yet fully understood, and whether earlier onset of puberty in obese girls is based on the activation of the hypothalamic-pituitary-gonadal axis is unclear. The most promising link between obesity and puberty is the adipokine leptin and its interaction with the kisspeptin system, which is an important regulator of puberty. However, peripheral action of adipose tissue (eg, via other adipokines, aromatase activity) could also be involved in changes to the onset of puberty. In addition, nutritional factors, epigenetics, or endocrine disrupting chemicals are potential mediators linking the onset of puberty to obesity. This Review summarises our knowledge concerning the relationship between obesity and onset and tempo of puberty, and the consequences of early puberty on obesity.

Compliance With Mobile Ecological Momentary Assessment Protocols in Children and Adolescents: A Systematic Review and Meta-Analysis

BACKGROUND

Mobile device-based ecological momentary assessment (mobile-EMA) is increasingly used to collect participants' data in real-time and in context. Although EMA offers methodological advantages, these advantages can be diminished by participant noncompliance. However, evidence on how well participants comply with mobile-EMA protocols and how study design factors associated with participant compliance is limited, especially in the youth literature.

OBJECTIVE

To systematically and meta-analytically examine youth's compliance to mobile-EMA protocols and moderators of participant compliance in clinical and nonclinical settings.

METHODS

Studies using mobile devices to collect EMA data among youth (age ≤18 years old) were identified. A systematic review was conducted to describe the characteristics of mobile-EMA protocols and author-reported factors associated with compliance. Random effects meta-analyses were conducted to estimate the overall compliance across studies and to explore factors associated with differences in youths' compliance.

RESULTS

This review included 42 unique studies that assessed behaviors, subjective experiences, and contextual information. Mobile phones were used as the primary mode of EMA data collection in 48% (20/42) of the reviewed studies. In total, 12% (5/42) of the studies used wearable devices in addition to the EMA data collection platforms. About half of the studies (62%, 24/42) recruited youth from nonclinical settings. Most (98%, 41/42) studies used a time-based sampling protocol. Among these studies, most (95%, 39/41) prompted youth 2-9 times daily, for a study length ranging from 2-42 days. Sampling frequency and study length did not differ between studies with participants from clinical versus nonclinical settings. Most (88%, 36/41) studies with a time-based sampling protocol defined compliance as the proportion of prompts to which participants responded. In these studies, the weighted average compliance rate was 78.3%. The average compliance rates were not different between studies with clinical (76.9%) and nonclinical (79.2%; P=.29) and studies that used only a mobile-EMA platform (77.4%) and mobile platform plus additional wearable devices (73.0%, P=.36). Among clinical studies, the mean compliance rate was significantly lower in studies that prompted participants 2-3 times (73.5%) or 4-5 times (66.9%) compared with studies with a higher sampling frequency (6+ times: 89.3%). Among nonclinical studies, a higher average compliance rate was observed in studies that prompted participants 2-3 times daily (91.7%) compared with those that prompted participants more frequently (4-5 times: 77.4%; 6+ times: 75.0%). The reported compliance rates did not differ by duration of EMA period among studies from either clinical or nonclinical settings.

CONCLUSIONS

The compliance rate among mobile-EMA studies in youth is moderate but suboptimal. Study design may affect protocol compliance differently between clinical and nonclinical participants; including additional wearable devices did not affect participant compliance. A more consistent compliance-related result reporting practices can facilitate understanding and improvement of participant compliance with EMA data collection among youth.

The Role of Assimilating to the US Culture and the Relationship Between Neighborhood Ethnic Composition and Dietary Intake Among Hispanic Youth

BACKGROUND

Dietary fiber and sugar intake have been shown to affect metabolic health in overweight Hispanic youth. Evidence on the influence of culture on fiber and sugar intake in Hispanic youth is limited.

METHODS

The associations among score for levels of assimilation, neighborhood ethnic characteristics, and daily total and added dietary sugar and dietary fiber intake were assessed using regression analyses.

RESULTS

One hundred twenty-four Hispanic youth (age = 13.6 ± 3.0, 106 female) were included. The proportion of Hispanic population in the neighborhood was positively associated with fiber intake (standardized β = 0.205, p < 0.01) and inversely associated with added (standardized β = -0.234, p < 0.01) and total sugar intake (standardized β = -0.229, p < 0.01). Youth's self-identified levels of assimilation inversely moderated (standardized β = -0.465, p = 0.036) the association between %HP and dietary fiber intake.

CONCLUSIONS

Hispanic youth residing in areas of that are predominantly populated with Hispanics may be protected from conforming to unhealthy dietary behaviors. This protective effect is weaker among Hispanic youth with higher level of assimilation.

Metabolic Syndrome in Children and Adolescents: a Critical Approach Considering the Interaction between Pubertal Stage and Insulin Resistance

Pediatricians increasingly diagnose the metabolic syndrome (MetS) in recent years to describe cardiovascular risk and to guide management of the obese child. However, there is an ongoing discussion about how to define the MetS in childhood and adolescence. Since insulin resistance-the major driver of MetS-is influenced by pubertal stage, it is questionable to use definitions for MetS in children and adolescents that do not take into account pubertal status. A metabolic healthy status in prepubertal stage does not predict a metabolic healthy status during puberty. Furthermore, cardiovascular risk factors improve at the end of puberty without treatment. However, having a uniform internationally accepted definition of the MetS for children and adolescents would be very helpful for the description of populations in different studies. Therefore, the concept of MetS has to be revisited under the influence of puberty stage.

Effects of high-sugar and high-fiber meals on physical activity behaviors in Latino and African American adolescents

OBJECTIVE

This crossover experimental study examined the acute effects of high-sugar/low-fiber (HSLF) vs. low-sugar/high-fiber (LSHF) meals on sedentary behavior (SB) and light-plus activity (L+) in minority adolescents with overweight and obesity.

METHODS

87 Latino and African American adolescents (mean age = 16.3 ± 1.2 years, mean BMI z-score = 2.02 ± 0.52, 56.8% Latino, 51.1% male) underwent two experimental meal conditions during which they consumed HSLF or LSHF meals. Physical activity and SB were measured using accelerometers, and blood glucose and insulin were collected every 30 minutes over 5 hours. Mixed models were used to examine the temporal trends of SB and L+, whether the temporal trends of SB and L+ differed by meal condition, and the influence of blood glucose and insulin on the activity behaviors.

RESULTS

SB and L+ fluctuated over time during the HSLF condition but were stable during the LSHF condition. SB and L+ were influenced by the blood glucose response to the HSLF meals. Insulin did not influence SB or L+ in either meal condition.

CONCLUSIONS

Sugar and fiber content of meals can have differing acute impacts on activity behaviors in minority adolescents with overweight and obesity, possibly due to differing metabolic responses.