A Systematic Review of the Associations of Adiposity and Cardiorespiratory Fitness With Arterial Structure and Function in Nonclinical Children and Adolescents.

PURPOSE: To summarize the evidence on associations of adiposity and cardiorespiratory fitness (CRF) with arterial structure and function in nonclinical children and adolescents. METHODS: Two researchers conducted a search in 5 electronic databases in April 2022 to find studies in nonclinical youth (age 5-17.9 y) reporting multivariable associations. Studies were eligible if adiposity and/or CRF were used as the predictor and arterial structure and/or function was the outcome. The Quality Assessment Tool for Quantitative Studies was used to assess methodological quality for experimental studies, and a modified version was used for observational studies. RESULTS: Ninety-nine studies (72.7% cross-sectional) were included. Ninety-four assessed associations between adiposity and arterial outcomes, most using overall body proportion (n = 71), abdominal (n = 52), or whole-body adiposity (n = 40). Most evidence was inconsistent or nonsignificant, but 59 studies suggested higher abdominal adiposity and worse body proportion were associated with adverse arterial outcomes. Twenty-one assessed associations between CRF and arterial outcomes, with findings inconsistent. Most evidence was rated weak in quality. CONCLUSION: While high adiposity may contribute to poor arterial outcomes, evidence is limited regarding CRF. Future studies should disentangle these associations by studying youth with healthy adiposity but poor CRF, or vice versa, using longitudinal or experimental study designs.

Patterns of Objectively Measured Sedentary Time and Emotional Disorder Symptoms Among Youth.

OBJECTIVE: We examined the within-person longitudinal and bidirectional associations between patterns of sedentary time accumulation [alpha (sedentary bout duration/length), sedentary breaks (number of breaks in sedentary bouts)], and symptoms of major depressive disorder and generalized anxiety disorder. METHODS: Children [N = 167, 10.1(0.9) years old, 54.5% female, 59.3% Hispanic, 35.9% overweight/obese at baseline] participated in a 3-year longitudinal study that consisted of assessments of sedentary time, and depressive and anxiety symptoms. At each assessment, participants wore accelerometers and completed the Revised Child Anxiety and Depression Scale. Separate random intercept cross-lagged panel models estimated the within-person longitudinal and bidirectional associations between alpha, sedentary breaks, and symptoms of major depressive disorder and generalized anxiety disorder across chronological age intervals. RESULTS: Having greater than one's own usual depressive symptoms at age 11 was associated with fewer sedentary breaks 1 year later. Having greater than one's own usual generalized anxiety symptoms at age 11 was associated with longer sedentary bouts and fewer sedentary breaks 1 year later. In contrast, having greater than one's own usual sedentary breaks at age 10 was associated with fewer generalized anxiety symptoms 1 year later. All other associations, including at younger ages, were null. CONCLUSION: Deviations from one's usual levels of depressive or anxiety symptoms may be important for how sedentary time is subsequently accumulated. Intraindividual processes appear to be at play, therefore more within-person research is needed. Intervention strategies for promoting a healthier accumulation of sedentary time may consider targeting occasions when depressive and anxiety symptoms are greater than usual.

Perceived stress and associations between physical activity, sedentary time, and interstitial glucose in healthy adolescents.

BACKGROUND: Less moderate to vigorous physical activity (MVPA), more sedentary time (ST), and higher perceived stress are related to type 2 diabetes mellitus (T2DM) occurrence, but observational evidence addressing the interaction of these factors is lacking in youth. This pilot study investigated momentary stress as a moderator in the acute associations of MVPA and ST with subsequent glucose in healthy adolescents. METHODS: Participants (N=15, Mage=13.1±1.0 years, 10 girls, 5 with overweight/obesity) simultaneously wore a continuous glucose monitor (CGM), thigh-mounted accelerometer, and reported momentary stress via random ecological momentary assessments (EMA; Time T) for 7-14 days. MVPA and ST (min) were calculated for 60- and 120-minute time windows before each EMA prompt (Time T-1). Mean CGM-measured interstitial glucose (mg/dL) was calculated after each prompt (Mmin=120.0±25.4; Time T+1). Multilevel models assessed whether within-subject MVPA and ST (Time T-1) predicted mean glucose (Time T+1), with momentary stress as a moderator (Time T). RESULTS: There were 513 time-matched EMA reports of stress, accelerometer, and CGM data. Momentary stress moderated the effects of MVPA 60 (ß=-0.22, p=.001) and 120 min (ß=-0.08, p=.02) before the prompt on subsequent glucose levels. When youth spent more time in MVPA than their average and when momentary stress was higher than their average, subsequent glucose was lower. Stress did not moderate associations of ST with glucose (p>.05). CONCLUSIONS: Higher momentary stress may interact with higher MVPA to lower subsequent glucose in youth. Accelerometers, EMA, and CGMs can be integrated in future studies to further understand these associations in free-living environments.

Exploring Generation Z and Young Millennials' Perspectives of a Spiritual Self-Care App and Their Spiritual Identity (Skylight): Qualitative Semistructured Interview Study.

BACKGROUND: Generation Z and young millennials (ages 18-35 years), collectively referred to as GenZennials, are connected to technology and the internet like no other generation before them. This has mental health implications, such as increased rates of anxiety and stress. Recent research has shown that app-based mental health interventions can be useful to address such mental health concerns. However, spirituality is an untapped resource, especially since GenZennials largely identify as spiritual and already integrate spiritual practices into their self-care. OBJECTIVE: There were four objectives to this study: (1) comprehensively explore reasons why GenZennials use a spiritual self-care app (ie, Skylight; Radiant Foundation), (2) understand how GenZennials identify spiritually, (3) understand the app's relevance to GenZennials, and (4) gather feedback and suggestions to improve the app. METHODS: Semistructured interviews were conducted with 23 GenZennials (ages 18-35 years; mean 28.7, SD 5.0 years; n=20, 87% female) who used the Skylight app. Interviews were 30 to 60 minutes and conducted on Zoom. Thematic analysis was used to analyze interviews. RESULTS: Five major categories emerged from the analysis, each encompassing one to several themes: (1) reasons for using the Skylight app, (2) content favorites, (3) defining spiritual identity, (4) relevance to GenZennials, and (5) overall improvement recommendations. Participants used the app for various reasons including to relax, escape, or ground themselves; improve mood; and enhance overall health and wellness. Participants also cited the app's variety of content offerings and its free accessibility as their primary reasons for using it. Most participants identified themselves as solely spiritual (8/23/35%) among the options provided (ie, spiritual or religious or both), and they appreciated the app's inclusive content. Participants felt that the app was relevant to their generation as it offered modern content (eg, spiritual self-care activities and short content). Participants recommended adding more personalization capabilities, content, and representation to the app. CONCLUSIONS: This is the first study to qualitatively explore GenZennials' perspectives and the use of a spiritual self-care app. Our findings should inform the future creation and improvement of spiritual self-care apps aimed at cultivating GenZennials' spiritual and mental well-being. Future research is warranted to examine the effects of using a spiritual self-care app on GenZennial mental health.

A Spiritual Self-Care Mobile App (Skylight) for Mental Health, Sleep, and Spiritual Well-Being Among Generation Z and Young Millennials: Cross-Sectional Survey.

BACKGROUND: Generation Z (Gen Z) and young millennials (GenZennials) (ages 18-35 years) are unique in that they either have no memory of or were born shortly after the internet "explosion." They are constantly on the internet, face significant challenges with their mental health and sleep, and are frequent users of digital wellness apps. GenZennials also uniquely identify with and practice spirituality, which has been linked to better mental health and sleep in adult populations. Research has not examined digital approaches to spiritual self-care and its relationship to mental health and sleep in GenZennials. OBJECTIVE: The purpose of this study was to describe a sample of adult GenZennials who use a spiritual self-care app (ie, Skylight), describe how users engage with and perceive the app, and assess the relationship between frequency of using the app with mental health, sleep, and spiritual well-being. METHODS: Participants were 475 adult Gen Z (ages 18-28 years) and young millennial (ages 29-35 years) Skylight app users who responded to an anonymous survey on the web. The survey asked about demographics, spiritual self-care and practice, and user engagement and perceptions of the app. Outcome measures included 4 validated surveys for mental health (ie, depression, anxiety, and stress) and sleep disturbance, and one validated survey on spiritual well-being. Mean scores were calculated for all measures, and linear regressions were conducted to examine the relationship between the frequency of app use and mental health, sleep, and spiritual well-being outcomes. RESULTS: Participants were predominantly White (324/475, 68.2%) and female (255/475, 53.7%), and approximately half Gen Z (260/475, 54.5%) and half young millennials (215/475, 45.3%). Most users engaged in spiritual self-care (399/475, 84%) and said it was important or very important to them (437/475, 92%). Users downloaded the app for spiritual well-being (130/475, 30%) and overall health (125/475, 26.3%). Users had normal, average depressive symptoms (6.9/21), borderline abnormal anxiety levels (7.7/21), slightly elevated stress (6.7/16), and nonclinically significant sleep disturbance (5.3/28). Frequency of app use was significantly associated with lower anxiety (Moderate use: ß=-2.01; P=.02; high use: ß=-2.58; P<.001). There were no significant relationships between the frequency of app use and mental health, sleep, and spiritual well-being outcomes except for the personal domain of spiritual well-being. CONCLUSIONS: This is the first study to describe a sample of adult GenZennials who use a spiritual self-care app and examine how the frequency of app use is related to their mental health, sleep, and spiritual well-being. Spiritual self-care apps like Skylight may be useful in addressing anxiety among GenZennials and be a resource to spiritually connect to their personal spiritual well-being. Future research is needed to determine how a spiritual self-care app may benefit mental health, sleep, and spiritual well-being in adult GenZennials.

Longitudinal, prospective study of head impacts in male high school football players.

INTRODUCTION: Repetitive, subconcussive events may adversely affect the brain and cognition during sensitive periods of development. Prevention of neurocognitive consequences of concussion in high school football is therefore an important public health priority. We aimed to identify the player positions and demographic, behavioral, cognitive, and impact characteristics that predict the frequency and acceleration of head impacts in high school football players. METHODS: In this prospective study, three cohorts of adolescent male athletes (N = 53, 28.3% Hispanic) were recruited over three successive seasons in a high school American football program. Demographic and cognitive functioning were assessed at baseline prior to participating in football. Helmet sensors recorded impact frequency and acceleration. Each head impact was captured on film from five different angles. Research staff verified and characterized on-field impacts. Player-level Poisson regressions and year-level and impact-level linear mixed-effect models were used to determine demographic, behavioral, cognitive, and impact characteristics as predictors of impact frequency and acceleration. RESULTS: 4,678 valid impacts were recorded. Impact frequency positively associated with baseline symptoms of hyperactivity-impulsivity [ß(SE) = 1.05 impacts per year per unit of symptom severity (1.00), p = 0.01] and inattentiveness [ß(SE) = 1.003 impacts per year per T-score unit (1.001), p = 0.01]. Compared to quarterbacks, the highest acceleration impacts were sustained by kickers/punters [ß(SE) = 21.5 g's higher (7.1), p = 0.002], kick/punt returners [ß(SE) = 9.3 g's higher (4.4), p = 0.03], and defensive backs [ß(SE) = 4.9 g's higher (2.5), p = 0.05]. Impacts were more frequent in the second [ß(SE) = 33.4 impacts (14.2), p = 0.02)] and third [ß(SE) = 50.9 impacts (20.1), p = 0.01] year of play. Acceleration was highest in top-of-the-head impacts [ß(SE) = 4.4 g's higher (0.8), p<0.001]. CONCLUSION: Including screening questions for Attention-Deficit/Hyperactivity Disorder in pre-participation evaluations can help identify a subset of prospective football players who may be at risk for increased head impacts. Position-specific strategies to modify kickoffs and correct tackling and blocking may also reduce impact burden.

Time-Varying Associations Between Device-Based and Ecological Momentary Assessment-Reported Sedentary Behaviors and the Concurrent Affective States Among Adolescents: Proof-of-Concept Study.

BACKGROUND: Previous studies on affective state-sedentary behavior (SB) associations have not accounted for their potentially time-varying nature and have used inconsistent SB measurement modalities. We investigated whether the strength of the associations between affective states and SB varied as a function of the time of day and by SB measurement modality (device-measured SB vs ecological momentary assessment-reported screen-based SB) in youth. OBJECTIVE: This study aimed to establish a proof of concept that SB-affective state associations may not be static during the day. In addition, we aimed to inform the methodology of future work, which may need to model associations as functions of the time of day and carefully consider how SB is operationalized or measured. METHODS: A total of 15 adolescents (age: mean 13.07, SD 1.03 years; 10/15, 67% female; 6/15, 40% Hispanic; 10/15, 67% healthy weight) wore thigh-mounted activPAL accelerometers and simultaneously reported their screen-based SBs and concurrent positive and negative affective states via ecological momentary assessment for 7 to 14 days (N=636 occasions). Time-varying effect models (varying slopes) examined how each measure of SB was associated with concurrent affective states from 7 AM to 8 PM. RESULTS: Time-varying effect model plots revealed that these associations varied in strength throughout the day. Specifically, device-based SB was related to greater concurrent negative affect only after approximately 5 PM and was unrelated to concurrent positive affect. Screen-based SB was related to greater concurrent negative affect only from 7 AM to approximately 9 AM. This was also related to greater concurrent positive affect from 7 AM to approximately 9:30 AM and from approximately 3 PM to approximately 7 PM. CONCLUSIONS: We provide preliminary evidence to suggest that future confirmatory studies investigating the SB-affective state relationship should consider the time-varying nature of these associations and SB measurement modality. There may be critical time windows when specific types of SBs co-occur with affect, suggesting that interventions may need tailoring to the time of day and type of SB if future studies using similar methodologies can replicate our findings.

Cross-Sectional and Longitudinal Associations between Non-School Time Physical Activity, Sedentary Time, and Adiposity among Boys and Girls: An Isotemporal Substitution Approach.

This study investigated the cross-sectional and longitudinal associations of the substitution of non-school time light physical activity (LPA), moderate-to-vigorous physical activity (MVPA), and sedentary time (ST) with adiposity in boys and girls. Boys (n = 65, baseline Mage= 9.93 ± 0.86 years) and girls (n = 77, baseline Mage = 10.17 ± 0.95 years) wore waist-worn accelerometers (ActiGraph GT3X) at baseline and at a 30-month follow-up, from which non-school time LPA, MVPA, ST, and total device wear were quantified. Body mass index (BMI) and waist-to-height-ratio (WHR) were measured at baseline and follow-up. Body fat percent (BF%) was obtained at follow-up only. Isotemporal substitution models assessed the cross-sectional and longitudinal associations of reallocating non-school time activity with BMI, WHR and BF%. In boys, replacing 30 min/day of LPA with MVPA was cross-sectionally (ß = -8.26, p < 0.05) associated with a lower BF%. Replacing 30 min/day of ST with MVPA was cross-sectionally (ß = -6.02, p < 0.05) associated with a lower BF% in boys. Longitudinally in boys, replacing 30 min of change in LPA with MVPA (ß = -7.42, p < 0.10) and replacing 30 min of change in MVPA with ST (ß = 5.78, p < 0.10) over 30 months was marginally associated with less BF%. Associations were null in girls (p > 0.05). These results may support targeting activity reallocation during non-school time for the purposes of adiposity improvement in boys. A multi-behavioral approach may be more appropriate for girls, as non-school time activity may not be driving adiposity status.

A Cross-Sectional Examination of Patterns of Sedentary Behavior and Cardiometabolic Risk in Community-Dwelling Adults Aged 55 Years and Older.

INTRODUCTION: Sedentary behavior (SB) is highly prevalent among older adults, with more than 25% engaging in 6 hours or more of SB daily. SB has been associated with several cardiometabolic biomarkers in younger adults; however, there is a paucity of research in older populations. This study examined associations between patterns of SB and cardiometabolic biomarkers in community-dwelling adults aged 55 years and older. METHODS: Data were drawn from a convenience sample of 54 community-dwelling individuals (12 males, 42 females; mean age = 72.6 ± 6.8 years, range = 56-89 years). Cardiometabolic biomarkers assessed included systolic (SBP) and diastolic blood pressure (DBP), body mass index, waist circumference, and fasting blood glucose and cholesterol parameters. SB was assessed via accelerometry over a 7-day period, and measures included daily time in SB, number and length of sedentary bouts, the number and length of breaks between sedentary bouts, moderate-to-vigorous physical activity (MVPA), and light physical activity (LPA). Associations between the SB measures and each cardiometabolic risk factor were examined using separate stepwise multiple regression models, controlling for sex, MVPA, and accelerometer wear time. Isotemporal substitution models were used to examine the change in cardiometabolic outcomes when SB is replaced by an equal duration of either LPA or MVPA. RESULTS: Adjusted regression analyses showed that daily sedentary time was positively associated with DBP (ß = 0.052, ∆R 2 = 0.112, p = 0.022) and inversely associated with HDL cholesterol (ß = -0.111, ∆R 2 = 0.121, p = 0.039). Sedentary bout length was also associated with DBP and HDL cholesterol (ß = 0.575, ∆R 2 = 0.152, p = 0.007; ß = -1.529, ∆R 2 = 0.196, p = 0.007, respectively). Replacement of 10 minutes of SB a day with LPA was associated with improved DBP and HDL cholesterol (p ≤ 0.05). No other significant associations (p ≤ 0.05) were found. CONCLUSION: Sitting for prolonged periods of time without interruption is unfavorably associated with DBP and HDL cholesterol. Prospective studies should identify causal relationships and observe specific changes in cardiometabolic profiles in older populations.

The relationship between metabolic syndrome, cytokines and physical activity in obese youth with and without Prader-Willi syndrome.

BACKGROUND: The objective of this study was to examine the associations between adiposity, metabolic syndrome (MetS), cytokines and moderate-to-vigorous physical activity (MVPA) in youth with Prader-Willi syndrome (PWS) and non-syndromic obesity (OB). METHODS: Twenty-one youth with PWS and 34 with OB aged 8-15 years participated. Measurements included body composition, blood pressure, fasting blood markers for glucose control, lipids and inflammation and MVPA. Group differences for adiposity, MetS, blood parameters and MVPA were determined using independent t-tests and chi-square (χ2) analyses. Bivariate correlations and analysis of variance (ANOVA) examined the associations between adiposity, MetS severity, cytokines and MVPA. RESULTS: PWS presented similar percentage of body fat (%), lower body mass index (BMI) z-scores, insulin resistance, triglycerides, MetS severity, C-reactive protein (CRP), tumor necrosis factor-α (TNF-α) and MVPA and higher high-density lipoprotein (HDL) and adiponectin (ADP) than OB. Fewer PWS presented MetS based on BMI z-score (61.9% vs. 91.2%) and glucose (14.3% vs. 44.1%) compared to OB. In all youth, MetS severity was significantly associated with body fat %, ADP, interleukin-6 (IL-6) and TNF-α and also with CRP in PWS, but associations became non-significant for CRP and IL-6 when controlling for body fat %. In PWS, those with low MVPA had significantly higher TNF-α than those with high MVPA (1.80±0.45 vs. 1.39±0.26 pg/mL). CONCLUSIONS: Although PWS presented better cardiometabolic profiles than OB and lower MetS risk, associations between body fat, MetS and cytokines were somewhat similar for both groups, with the exception of CRP. Results suggest a potential role for MVPA related to MetS and inflammation and extend associations shown in OB to PWS.