Offspring sex modifies the association between early-pregnancy adiposity and 2-year-old physical activity-The Glowing Study.

BACKGROUND: Rodent models suggest that in utero exposure to under and overnutrition programs offspring physical activity (PA) behaviors. Such nexus has not been established in humans. This study evaluated the association of early pregnancy maternal adiposity with offspring PA at age 2 years (2-yo-PA) taking into consideration prenatal and postnatal factors. METHODS: Women (n = 153) were enrolled early in pregnancy (<10 weeks). At enrollment, maternal adiposity [air displacement plethysmography, fat mass index (FMI, kg/m2)] and PA (accelerometers, activity counts) were measured, and age, race, and education self-reported. Gestational weight gain was measured at the research facility. Offspring birthweight and sex were self-reported. At age 2 years, parental feeding practices (child feeding questionnaire) were assessed, whereas anthropometrics (length and weight) and physical activity (accelerometers) were objectively measured. Offspring body mass index z-scores were calculated. Generalized linear regression analysis modeled the association of maternal FMI and 2-yo-PA [average activity counts (AC)4/day]. RESULTS: In bivariate associations, 2-yo-PA did not associate with maternal FMI (ß = -0.22, CI = -0.73 to 0.29, p = 0.398). However, maternal FMI interacted with offspring sex in association with 2-yo-PA. Specifically, 2-yo-PA was lower in girls (ß = -1.14, CI = -2.1 to -0.18, p = 0.02) compared to boys when maternal FMI was ≥7 kg/m2. When stratified by sex, 2-yo-PA of girls negatively associated with maternal FMI (ß = -0.82, CI = -1.43 to 0.29, p = 0.009) while no association was found between maternal FMI and boy's PA (ß = 0.32, CI = -0.38 to 1.01, p = 0.376). CONCLUSIONS: The association of 2-yo-PA and early pregnancy maternal adiposity was modified by offspring sex. Offspring's physical activity decreased with increasing early pregnancy adiposity maternal in girls but not boys in second parity dyads.

Relationships between physical behaviour phenotypes of mothers in pregnancy and their offspring with child body composition.

AIM: The aim of this study was to identify physical behaviour phenotypes in mothers in the first trimester and in their offspring at 24 months of age. The secondary aim was to examine relationships between mother and child behaviours with child body composition at age 24 months. METHODS: Longitudinal secondary analysis of the Glowing cohort collected between 1 February 2011 and 22 August 2017 in Little Rock, Arkansas. Behaviours were measured using ankle-worn accelerometers in mothers during the first trimester and offspring at 24 months of age, including total activity, sleep, sedentary time and a novel variable of daily variation, patternicity. Child body fat was measured using quantitative nuclear magnetic resonance. RESULTS: Three phenotypes were identified for mothers and children (n = 159 complete dyads). There were no relationships between mother and child phenotypes, but higher maternal patternicity was associated with higher child patternicity (0.2, 95% CI 0.1, 0.3, p = 0.001). There were no associations between mother or child phenotypes with child body composition, however higher child activity was associated with lower body fat (-0.01, 95% CI: -0.02, -0.001, p = 0.031). CONCLUSION: Limited associations were found between mothers' pregnancy physical behaviours with child behaviours or child body composition at 24 months of age. Factors such as child diet or current parental physical activity may be better predictors of early childhood outcomes.

Evaluation of the Little Rock Green Schoolyard initiative: a quasi-experimental study protocol.

BACKGROUND: Evidence suggests that access to green schoolyards may facilitate vigorous play and lead to increased physical activity, which could lead to improved academic outcomes and reduce excess childhood weight gain. Greener schoolyards can also provide additional outdoor amenities that help the community at large. The Little Rock Green Schoolyard Initiative, a program aiming to promote outdoor learning and play in two of the city's community schools, provides a natural experiment to evaluate the role of such interventions. This article presents the protocols and study plans that will be used to evaluate this community-led initiative on several outcomes including physical activity, sleep quality, use of schoolgrounds, and perceptions of the school environment. Administrative datasets will be used to assess exposure to green schoolyard improvements on academic achievement, attendance, and disciplinary referrals during elementary school. METHODS: Data will be gathered in two community schools where the green schoolyard improvements are taking place and in two demographically-matched comparison schools located elsewhere within the Little Rock School District. Data will be collected before, during, and after the green schoolyard improvements go into effect. Physical activity and sleep quality will be measured using actigraphy. Physical activity will also be assessed through direct playground observations during recess and outside of school hours. During the final year of the study, administrative data will be assembled and evaluated using difference-in-differences estimation and synthetic controls, two causal inference methods from the program evaluation literature. DISCUSSION: The study is designed to provide new insights into the design, implementation, and evaluation of playgrounds among schoolchildren, especially those who are at risk of developing severe obesity during their elementary school years. The research herein will develop empirical data, elucidate potential mechanisms, and practical experience for future study, policymaking, and health services.

Physical Activity, Sedentary and Sleep Phenotypes in Women During the First Trimester of Pregnancy.

OBJECTIVES: Patterns of physical behaviors including physical activity, sedentary time, and sleep are unknown during pregnancy, but are likely to influence health outcomes. The purpose was to first identify "physical behavior phenotypes" from accelerometer-measured physical behaviors in pregnant women during the first trimester and secondly, to explore the associations between the identified phenotypes with demographic variables and body-mass-index (BMI). METHODS: Data were from the Glowing Study (gov ID: NCT01131117), collected between 2011 and 2017 with accelerometer-measured physical behaviors of women in their 12th week of pregnancy. Latent class analysis was used to identify patterns of total physical activity, sleep time, sedentary time, and variation in physical activity. Maternal Body-Mass-Index (BMI). BMI and sociodemographic characteristics were compared between physical behavior phenotypes. RESULTS: A total of 212 pregnant women were included in the study (mean age 30.2 years (range 22.1 to 42.4), mean days wear 4.3 (SD 0.7)). Three physical behavior phenotypes were identified from the four physical behavior constructs: low sedentary and stable activity (n = 136, 64%), variable activity (n = 39, 18%), high sedentary and low sleep (n = 37, 17%). BMI, race, and education were significantly different between the three phenotypes, with the low sedentary and stable activity phenotype having the lowest BMI and a higher percentage of white and college educated women. CONCLUSIONS FOR PRACTICE: Total physical activity and physical behavior phenotypes during the first trimester were associated with early-pregnancy BMI, race, and education. Future research should examine whether these physical behavior phenotypes are associated with maternal and child health outcomes.

Musculoskeletal pain latent classes and biopsychosocial characteristics among emerging adults.

BACKGROUND: Emerging adults (aged 18-29) report high levels of musculoskeletal pain; however, it is unknown if body location and intensity patterns are related to different biopsychosocial characteristics. This study identified patterns of self-reported musculoskeletal pain among emerging adults and assessed if there were differences in their lifestyle and psychological characteristics. METHODS: Data from survey responses from a large public university and a large medical university in the United States were used (n = 1,318). Self-reported pain location and intensity at five body regions were assessed, and latent class analysis identified classes separately for men and women. Mental health, physical activity, and sleep outcomes were compared between the classes. RESULTS: Four classes were identified for men and women. Three of the classes were consistent between genders - "no pain," (women = 28% of their sample; men = 40% of their sample) "mild multisite pain," (women = 50%; men = 39%) and "moderate-severe multisite pain" (women = 9%; men = 7%). The fourth class for women was "moderate spine pain," (13%) and for men was "mild extremity pain" (13%). For both men and women, the "moderate-severe multisite" pain classes reported the highest levels of depression, anxiety, and stress, poorer sleep, and higher work physical activity than the "no pain" class. The "mild multisite" and "moderate spine" (women only) pain classes fell between the "no pain" and "moderate-severe" pain classes. The characteristics of the "mild upper extremity pain" class for men was similar to the "no pain" class. CONCLUSIONS: The identified classes provide unique information on pain location and intensity in emerging adults. The high prevalence of "mild multisite pain" (n = 593; 45% of the total sample) demonstrates an intervention opportunity during this age range to prevent further increases in musculoskeletal pain later in life. Future work should assess the longitudinal outcomes of these pain classes, the impact of interventions for this age group, and the balance between leisure and occupational physical activity when addressing musculoskeletal health.

Developmental trajectories of sleep during childhood and adolescence are related to health in young adulthood.

AIM: Sleep behaviour is correlated and causally related to physical and mental health. Limited longitudinal data exist on the associations of poor sleep behaviour in childhood and adolescence with adult health. Parent-reported sleep behaviours from 1993 participants of the Raine Study (at ages 5, 8, 10, 14, 17) were used to determine sleep trajectories (using latent class growth analysis). METHODS: Measures of physical and mental health were compared between sleep trajectories using generalised linear models (at age 20). RESULTS: Three sleep trajectories were identified as follows: 43% of participants belonged to a trajectory with 'consistently minimal' sleep problems, 49% showed some 'declining' in reporting of sleep problems incidence and 8% had 'persistent' sleep problems. Participants in the 'consistently minimal' trajectory had better physical and mental health outcomes at age 20 compared to those in the 'declining' and 'persistent' trajectories. For example, 'consistently minimal' participants had significantly lower body fat percentage (mean difference: -3.89% (95% CI: -7.41 to -0.38)) and a higher (better) SF-12 mental component score (mean difference: 4.78 (95% CI: 2.35-7.21)) compared to participants in the 'persistent' trajectory. CONCLUSION: Poor sleep behaviour across childhood and adolescent years is related to poorer physical and mental health in young adulthood.

Associations between meeting sleep, physical activity or screen time behaviour guidelines and academic performance in Australian school children.

BACKGROUND: Current guidelines suggest too little sleep, too little physical activity, and too much sedentary time are associated with poor health outcomes. These behaviours may also influence academic performance in school children. The primary purpose of this study was to examine the relationships between sleep, physical activity, or sedentary behaviours and academic performance in a school with a well-developed and integrated technology use and well-being program. METHODS: This was a cross-sectional survey of students (n = 934, Grades 5-12) in an Australian school with a bring-your-own device (tablet or laptop computer) policy. Students reported sleep, physical activity, and sedentary (screen and non-screen) behaviours. Academic performance was obtained from school records. Linear regressions were used to test the association between behaviours and academic performance outcomes. RESULTS: Seventy-four percent of students met sleep guidelines (9 to 11 h for children 5-13 years and 8 to 10 h for 14-17 year olds), 21% met physical activity guidelines (60 min of moderate-to-vigorous physical activity every day), and 15% met screen time guidelines (no more than 2 h recreational screen time per day); only 2% met all three. There were no associations between meeting sleep guidelines and academic performance; however later weekend bedtimes were associated with poorer academic performance (- 3.4 points on the Average Academic Index, 95%CI: - 5.0, - 1.7, p < .001). There were no associations between meeting physical activity guidelines and academic performance. Meeting screen guidelines was associated with higher Average Academic Index (5.8, 95%CI: 3.6, 8.0, p < .001), Maths 7.9, 95%CI: 4.1, 11.6, p < .001) and English scores (3.8, 95%CI: 1.8, 5.8, p < .001) and higher time in sedentary behaviours was associated with poorer academic performance, including total sedentary behaviours in hrs/day (5.8 points on Average Academic Index, 95%CI: 3.6, 8.0, p < .001. Meeting at least two of the three behaviour guidelines was associated with better academic performance. CONCLUSIONS: Sleep and sedentary behaviours were linked to academic performance. School communities should emphasize comprehensive wellness strategies to address multiple behaviours to maximize student health and academic success.

Mobile Ecological Momentary Assessment of Postconcussion Symptoms and Recovery Outcomes.

OBJECTIVE: Evaluate mobile ecological momentary assessment (mEMA) as an approach to measure sport-related concussion (SRC) symptoms, explore the relationships between clinical outcomes and mEMA, and determine whether mEMA was advantageous for predicting recovery outcomes compared to traditional symptom report. SETTING: Outpatient concussion clinic. PARTICIPANTS: 20 athletes aged 12 to 19 years with SRC. METHODS: Prospective study of mEMA surveys assessing activity and symptoms delivered via mobile application (3 time blocks daily) and clinical assessment at visit 1 (<72 hours postinjury) and visit 2 (6-18 days postinjury). Linear mixed models examined changes in mEMA symptoms over time and relationships among simultaneous report of activity type (cognitive, physical, sedentary, vestibular) and symptoms. Linear regressions evaluated the association among symptoms for activity types and clinical outcomes. MAIN MEASURES: mEMA symptom scores, Post-Concussion Symptom Scale, neurocognitive testing, vestibular/oculomotor screening (VOMS). RESULTS: mEMA response rate was 52.4% (N = 1155) for prompts and 50.4% per participant. Symptoms were lower in the morning (P < .001) compared with afternoon and evening. Higher mEMA symptoms were reported during vestibular compared with physical (P = .035) and sedentary (P = .001) activities. mEMA symptoms were positively associated with Post-Concussion Symptom Scale (PCSS) (P = .007), VOMS (P = 0.001-0.002), and recovery time (P < .001), but not neurocognitive scores. mEMA symptom score (P = .021) was a better predictor of recovery time than PCSS at either clinic visit. CONCLUSION: mEMA overcomes barriers of traditional symptom scales by eliminating retrospective bias and capturing fluctuations in symptoms by time of day and activity type, ultimately helping clinicians refine symptom management strategies.

"From the moment I wake up I will use it every day, very hour": a qualitative study on the patterns of adolescents' mobile touch screen device use from adolescent and parent perspectives.

BACKGROUND: The use of mobile touch screen devices, e.g. smartphones and tablet computers, has become increasingly prevalent among adolescents. However, little is known about how adolescents use these devices and potential influences on their use. Hence, this qualitative study explored adolescents' perceptions on their patterns of use and factors influencing use, and perceptions and concerns from parents. METHODS: Semi-structured interviews were conducted with adolescents (n = 36; 11 to 18 years) and their parents/caregivers (n = 28) in Singapore recruited to represent males and females across a range of ages from different socioeconomic groups. Prompts covered weekday and weekend use patterns, types of activities, perspectives on amount of use, parental control measures and concerns. Interviews were recorded and transcribed. Transcripts were coded and thematic analysis was carried out. RESULTS: Smartphone was the most common mobile device owned and used by many of the adolescents, while only some used a tablet. Many adolescents and their parents felt that adolescents' MTSD use was high, frequent and ubiquitous, with frequent checking of device and multitasking during use. Reported influences of use included functional, personal and external influences. Some of the influences were irresistibility of mobile devices, lack of self-control, entertainment or relaxation value, and high use by peers, family and for schoolwork that contributed to high use, or school/parental control measures and lack of internet availability that limited use. Most adolescents were generally unconcerned about their use and perceived their usage as appropriate, while most parents expressed several concerns about their adolescents' use and perceived their usage as excessive. CONCLUSIONS: This study has provided rich insights into the patterns and influences of contemporary mobile device use by adolescents. Mobile device use has become an integral part of adolescents' daily routines, and was affected by several functional, personal and external influences which either facilitated or limited their use. There also seemed to be a strong inclination for adolescents to frequently check and use their mobile devices. There is an urgent need to understand the implications of these common adolescent behaviours to inform advice for wise mobile device use by adolescents.

Prospective bi-directional associations between sedentary time and physical activity with cognitive performance: a cohort study.

This prospective study determined whether: (1) objective physical activity (PA) and sedentary (SED) time at 9 years was associated with cognition at 15 years, (2) cognition at 9 years was associated with PA and SED at 15 years, and (3) the change in PA and SED from 9 to 15 years was associated with the change in cognition. Cognitive performance was assessed from picture vocabulary, verbal analogy, passage comprehension, and applied problem tasks. Regression models were used to explore each aim while adjusting for covariates. Among the combined sample, SED (min· day-1) at 9 years was unrelated with cognitive performance at 15 years, whereas participating in ≥ 60 min· day-1 of moderate-to-vigorous PA (MVPA) at 9 years predicted lower cognitive scores at 15 years. In the reverse direction, cognitive performance at 9 years was unrelated with SED and MVPA (min· day-1) at 15 years. Over 6 years, increased SED (min· day-1) predicted lower improvement to verbal analogy scores (B = -0.01, p = 0.028). In comparison, an increase (or relatively smaller decline) in MVPA (min· day-1) predicted greater improvement in applied problem scores (B = 0.06, p = 0.007). Contextual information regarding SED and MVPA behavior would help understand bi-directional associations of activity and cognition.

Mobile touch screen device use and associations with musculoskeletal symptoms and visual health in a nationally representative sample of Singaporean adolescents.

This study aimed to describe contemporary technology use, especially smartphones and tablets (mobile touch screen devices), and examine associations with musculoskeletal symptoms and visual health among adolescents in Singapore. A representative sample of 1884 adolescents (50.4% girls) from grades primary 5 to post-secondary (10-18 years old), recruited from 13 schools, completed an online questionnaire in class. Total technology use was high, with smartphone duration being highest (mean = 264 [SD = 243] min/day). Patterns of use, including multitasking and bout length, were influenced by gender, school level, type of device and activities. Musculoskeletal discomfort and visual symptoms were commonly reported. After adjusting for potential confounders, more hours/day of smartphone use was associated with increased risk of neck/shoulders, upper back, arms and wrist/hand discomfort (OR = 1.04[95%CI = 1.01-1.07] to 1.07[1.03-1.10]) and visual symptoms (OR = 1.05[1.02-1.08]), but was associated with decreased odds of myopia (OR = 0.97[0.94-0.99]). No significant associations were found for tablet use. Practitioner Summary: 1884 adolescents in Singapore completed an in-depth questionnaire regarding their use of technology. The smartphone was the device with the highest usage, and greater smartphone use was associated with increased odds of musculoskeletal and visual symptoms. High use of smartphones has physical health implications for adolescents.

A Preliminary Investigation of Accelerometer-Derived Sleep and Physical Activity Following Sport-Related Concussion.

OBJECTIVE: Describe changes in postconcussion activity levels and sleep throughout recovery in a sample of pediatric sport-related concussion (SRC) patients, and examine the predictive value of accelerometer-derived activity and sleep on subsequent clinical outcomes at a follow-up clinic visit. SETTING: Outpatient concussion clinic. PARTICIPANTS: Twenty athletes aged 12 to 19 years with diagnosed SRC. METHODS: Prospective study including visit 1 (<72 hours postinjury) and visit 2 (6-18 days postinjury). Linear regressions used to predict scores (ie, neurocognitive, vestibular/oculomotor) at visit 2 from accelerometer-derived data collected 0 to 6 days postinjury. Linear mixed models evaluated changes in activity and sleep across recovery. MAIN MEASURES: Symptom, neurocognitive, and vestibular/oculomotor scores; sleep and activity data (Actigraph GT3x+) RESULTS:: The maximum intensity of physical activity increased (P = .009) and time in bed decreased throughout recovery (P = .026). Several physical activity metrics from 0 to 6 days postinjury were predictive of worse vestibular/oculomotor scores at visit 2 (P < .05). Metrics indicative of poor sleep 0 to 6 days postinjury were associated with worse reaction time at visit 2 (P < .05). CONCLUSIONS: This exploratory study suggests physical activity and sleep change from the acute to subacute postinjury time period in adolescent SRC patients. In our small sample, excess physical activity and poor sleep the first week postinjury may be associated with worse outcomes at follow-up in the subacute stage of recovery. This study further supported the feasibility of research utilizing wearable technology in concussion patients, and future research in a large, diverse sample of concussion patients examined at concise time intervals postinjury is needed.

Correlates of physical activity and sedentary time in young adults: the Western Australian Pregnancy Cohort (Raine) Study.

BACKGROUND: The socioecological model proposes a wide array of factors that influence behaviours. There is a need to understand salient correlates of these activity behaviours in a specific population. However, few studies identified socio-demographic, behavioural, physical, and psychological correlates of objectively-assessed physical activity and sedentary time in young adults. METHODS: This was a cross-sectional analysis of participants in the Raine Study (a pregnancy cohort started in 1989). Australian young adults (mean 22.1 years ± SD 0.6) wore Actigraph GT3X+ accelerometers on the hip 24 h/day for seven days to assess moderate-to-vigorous physical activity (MVPA) and sedentary time (n = 256 women, n = 219 men). Potential correlates were assessed via clinical assessment and questionnaire and included socio-demographic variables (ethnicity, relationship status, work/study status, education, mothers education), health behaviours (food intake, alcohol consumption, smoking status, sleep quality), and physical and psychological health aspects (anthropometrics, diagnosed disorders, mental health, cognitive performance). Backwards elimination (p < 0.2 for retention) with mixed model regressions were used and the gender-stratified analyses were adjusted for demographic variables, waking wear time and number of valid days. RESULTS: Increased time spent in MVPA was associated with: being single (IRR 1.44 vs in a relationship living together, 95%CI: 1.17, 1.77, p = .001) in women; and better sleep quality in men (lower scores better IRR 0.97, 95%CI: 0.93, 1.00). Less time spent sedentary was associated with: lower mother's education (- 32.1 min/day, 95%CI -52.9, 11.3, p = 0.002 for having mother with no university degree vs at least a baccalaureate degree) and smoking (- 44.3 min/day, 95%CI: - 72.8, - 15.9, p = .0002) for women; lower education status (- 32.1 min/day, 95%CI: -59.5, - 4.8, p = 0.021 for having no university degree vs at least a baccalaureate degree) and lower depression scores in men (- 2.0, 95%CI: - 3.5, - 0.4, p = 0.014); more alcoholic drinks per week for women (- 1.9 min/day, 95%CI: -3.1, - 0.6, p = 0.003) and men (- 1.0, 95%CI: -1.8, - 0.3, p = 0.007). CONCLUSIONS: Less desirable correlates were associated with positive levels of activity in young Australian adult women and men. Interventions to increase MVPA and decrease sedentary activity in young adults need to specifically consider the life stage of young adults.

Accelerometer-Derived Activity Phenotypes in Young Adults: a Latent Class Analysis.

PURPOSE: To identify "activity phenotypes" from accelerometer-derived activity characteristics among young adults. METHODS: Participants were young adults (n = 628, mean age, 22.1, SD 0.6) in the Raine Study in Western Australia. Sex-specific latent class analyses identified sub-groups using eight indicators derived from 7-day hip-worn Actigraph GT3X+ accelerometers: daily steps, total daily moderate-to-vigorous physical activity (MVPA), MVPA variation, MVPA intensity, MVPA bout duration, sedentary-to-light ratio, sedentary-to-light ratio variation, and sedentary bout duration. RESULTS: Five activity phenotypes were identified for women (n = 324) and men (n = 304). Activity phenotype 1 for both women (35%) and men (30%) represented average activity characteristics. Phenotype 2 for women (17%) and men (16%) was characterized by below average total activity and MVPA (10.6 and 16.7 min of MVPA/day, women and men respectively). Phenotype 3 for women (15%) and men (23%) was characterized by below average total physical activity, average MVPA (32.6 and 36.5 min/day), high sedentary-light ratio and long sedentary bouts. Phenotype 4 differed between women (29%) and men (18%) but both had low sedentary-to-light ratios and shorter sedentary bouts. Finally, phenotype 5 in both women (4%) and men (12%) was characterized by extreme MVPA metrics (81.3 and 96.1 min/day). CONCLUSIONS: Five activity phenotypes were identified for each gender in this population of young adults which can help design targeted interventions to enhance or modulate activity phenotypes.

Mobile technology dominates school children's IT use in an advantaged school community and is associated with musculoskeletal and visual symptoms.

This paper describes the contemporary use of information technology devices by children in a socio-educationally advantaged school. A sample of 924 children (50% girls) from grades 5 to 12 (ages 10-19 years) completed an online survey in class. Total daily technology use was high and similar for girls (mean 219 (SD 148) mins/day) and boys (207 (142), p=.186). Tablet computer was the dominant device used in grades 5-9, with laptop computer the dominant device in grades 10-12. Patterns of exposure were influenced by gender, device, grade and purpose of use interactions. For example, girls used mobile phones more than boys for social purposes for grades 10 and 11, but not grade 12. Whilst children's attitudes to technology use were positive, musculoskeletal and visual symptoms were commonly reported. Hours/day tablet and phone use was related to neck/shoulder discomfort (OR = 1.07; 1.13) and visual symptoms (OR = 1.10; 1.07). Practitioner Summary: Technology use by children appears to be quite different now to a decade ago. This paper describes contemporary school children's use of various devices for various purposes. The survey of >900 children found high technology use, dominated by new mobile technologies, and associations with musculoskeletal and visual symptoms.

Objectively measured patterns of sedentary time and physical activity in young adults of the Raine study cohort.

BACKGROUND: To provide a detailed description of young adults' sedentary time and physical activity. METHODS: 384 young women and 389 young men aged 22.1 ± 0.6 years, all participants in the 22 year old follow-up of the Raine Study pregnancy cohort, wore Actigraph GT3X+ monitors on the hip for 24 h/day over a one-week period for at least one 'valid' day (≥10 h of waking wear time). Each minute epoch was classified as sedentary, light, moderate or vigorous intensity using 100 count and Freedson cut-points. Mixed models assessed hourly and daily variation; t-tests assessed gender differences. RESULTS: The average (mean ± SD) waking wear time was 15.0 ± 1.6 h/day, of which 61.4 ± 10.1% was spent sedentary, 34.6 ± 9.1% in light-, 3.7 ± 5.3% in moderate- and, 0.3 ± 0.6% in vigorous-intensity activity. Average time spent in moderate to vigorous activity (MVPA) was 36.2 ± 27.5 min/day. Relative to men, women had higher sedentary time, but also higher vigorous activity time. The 'usual' bout duration of sedentary time was 11.8 ± 4.5 min in women and 11.7 ± 5.2 min in men. By contrast, other activities were accumulated in shorter bout durations. There was large variation by hour of the day and by day of the week in both sedentary time and MVPA. Evenings and Sundays through Wednesdays tended to be particularly sedentary and/or inactive. CONCLUSION: For these young adults, much of the waking day was spent sedentary and many participants were physically inactive (low levels of MVPA). We provide novel evidence on the time for which activities were performed and on the time periods when young adults were more sedentary and/or less active. With high sedentary time and low MVPA, young adults may be at risk for the life-course sequelae of these behaviours.

Relationships between psychosocial outcomes in adolescents who are obese and their parents during a multi-disciplinary family-based healthy lifestyle intervention: One-year follow-up of a waitlist controlled trial (Curtin University's Activity, Food and Attitudes Program).

BACKGROUND: Limited studies have investigated relationships in psychosocial outcomes between adolescents who are obese and their parents and how psychosocial outcomes change during participation in a physical activity and healthy eating intervention. This study examined both adolescent and parent psychosocial outcomes while participating in a one - year multi-disciplinary family-based intervention: Curtin University's Activity, Food, and Attitudes Program (CAFAP). METHODS: Following a waitlist control period, the intervention was delivered to adolescent (n = 56, ages 11-16) and parent participants over 8 weeks, with one-year maintenance follow-up. Adolescent depression and quality of life, family functioning, and parent depression, anxiety, and stress were assessed at six time points: baseline and prior to intervention (e.g., waitlist control period), immediately following intervention, and at 3, 6, and 12 months post-intervention. Relationships between adolescent and parent psychosocial outcomes were assessed using Spearman correlations and changes in both adolescent and parent outcomes were assessed using linear mixed models. Changes in adolescent psychosocial outcomes were compared to changes in behavioural (physical activity and healthy eating) and physical (weight) outcomes using independent samples t-tests. RESULTS: The majority of psychosocial outcomes were significantly correlated between adolescents and parents across the one-year follow-up. Adolescent depression, psychosocial and physical quality of life outcomes significantly improved before or following intervention and were maintained at 6-months or one-year follow-up. Parent symptoms of depression, anxiety, and stress were reduced during waitlist and primarily remained improved. Changes in adolescent psychosocial outcomes were shown to be partially associated with behavioural changes and independent of physical changes. CONCLUSIONS: Adolescents in CAFAP improved psychosocial and physical quality of life and reversed the typical trajectory of depressive symptoms in adolescents who are obese during a one-year maintenance period. CAFAP was also effective at maintaining reductions in parent symptoms of depression, anxiety, and stress demonstrated during the waitlist period. TRIAL REGISTRATION: The trial was registered with the Australian and New Zealand Clinical Trials Registry (No. 12611001187932 ).

Multiple components of fitness improved among overweight and obese adolescents following a community-based lifestyle intervention.

Fitness is an important component of health, and obese adolescents regularly have poor fitness. Unfortunately, few have assessed the impact of community-based lifestyle interventions on multiple components of fitness. The purpose of this study was to assess the impact of participation in a community-based intervention involving adolescents and parents on multiple components of fitness of obese adolescents. In a within-subject, waitlist controlled clinical trial with 12 months follow-up in Western Australia, participants (n = 56) completed multiple fitness measures at baseline, immediately prior to beginning an 8-week intervention and at 3, 6 and 12 months during a maintenance period. Performance on the shuttle walk was improved immediately post-intervention (increase of 42.8 m, 95% CI: 7.5, 78.2) and at 12 months post-intervention (increase of 44.6 m, 95% CI: 1.3, 87.8) compared with pre-intervention. Muscle performance of quadriceps and deltoids were improved post-intervention (increase of 1.1 (95% CI: 0.1, 2.1) kg · F and 1.0 (0.02, 2.1) kg · F, respectively) and all muscle performance measures were improved at 12 months following the intervention. There were no changes in waist circumference. A community-based lifestyle programme such as Curtin University's Activity, Food and Attitudes Program (CAFAP) may be a viable strategy for improving fitness in overweight adolescents.

Exploration of the Mechanisms of Change in Constructs From Self-Determination Theory and Quality of Life During a Multidisciplinary Family-Based Intervention for Overweight Adolescents.

The current study explored whether a multidisciplinary family-based intervention underpinned by self-determination theory could enhance perceptions of parent need support, autonomous motivation, and quality of life in overweight and obese adolescents. Using a staggered-entry waitlist-period control design, adolescents (n = 56) were assessed at baseline and preintervention (within-participant control), immediately following intervention, and at 3, 6, and 12 month follow-ups. Parents were trained in need-supportive behaviors within the broader context of an 8-week multidisciplinary intervention attended jointly with adolescents. Following intervention, significant improvements were demonstrated in adolescent perceptions of parent need support, autonomous motivation, and quality of life, and changes were maintained at the 1-year follow-up. Mediation analyses revealed changes in perceptions of parent need support predicted changes in quality of life indirectly via changes in autonomous motivation. Findings suggest overweight and obese adolescents are likely to benefit from multidisciplinary family-based interventions that aim to train parents in need-supportive behaviors.

Rationale, design and methods for the 22 year follow-up of the Western Australian Pregnancy Cohort (Raine) Study.

BACKGROUND: Young adulthood is a critical life period for health and health behaviours. Related measurements collected before and after birth, and during childhood and adolescence can provide a life-course analysis of important factors that contribute to health and behaviour in young adulthood. The Western Australian Pregnancy Cohort (Raine) Study has collected a large number of such measurements during the fetal, perinatal, infancy, childhood and adolescence periods and plans to relate them to common health issues and behaviours in young adults, including spinal pain, asthma, sleep disorders, physical activity and sedentary behaviour and, work absenteeism and presenteeism. The aim of this paper is to describe the rationale, design and methods of the 22 year follow-up of the Raine Study cohort. METHODS/DESIGN: The Raine Study is a prospective cohort study. Participants still active in the cohort (n = 2,086) were contacted around the time of their 22nd birthday and invited to participate in the 22 year follow-up. Each was asked to complete a questionnaire, attend a research facility for physical assessment and an overnight sleep study, wear activity monitors for a week, and to maintain a sleep and activity diary over this week. The questionnaire was broad and included questions related to sociodemographics, medical history, quality of life, psychological factors, lifestyle factors, spinal pain, respiratory, sleep, activity and work factors. Physical assessments included anthropometry, blood pressure, back muscle endurance, tissue sensitivity, lung function, airway reactivity, allergic status, 3D facial photographs, cognitive function, and overnight polysomnography. DISCUSSION: Describing the prevalence of these health issues and behaviours in young adulthood will enable better recognition of the issues and planning of health care resources. Providing a detailed description of the phenotype of these issues will provide valuable information to help educate health professionals of the needs of young adults. Understanding the life-course risk factors of health issues and behaviours in young adulthood will have important health planning implications, supporting the development of targeted interventions to improve current health status and reduce the onset and development of further ill-health across adulthood.