Moderate-to-vigorous Physical Activity In Adolescents Research Articles

Where Are Czech Adolescents Active? The Patterns of Movement and Transport Behavior in Different Active Living Domains.

To understand the environmental determinants of physical activity (PA), precise spatial localization is crucial. This cross-sectional study focuses on the spatiotemporal distribution of PA among Czech adolescents (n = 171) using Global Positioning System loggers and accelerometers. The results showed that adolescents spent most of their time in sedentary behavior, with 57.2% and 58.5% of monitored time at home and school, respectively. The park and playground had the lowest proportion of sedentary behavior but also the lowest amount of moderate to vigorous PA (MVPA). However, when considering the time spent in each domain, the highest proportion of MVPA was seen in publicly accessible playgrounds (13.3% of the time). Chi-square analysis showed that the relative distribution of different PA intensities did not differ across spatial domains. Based on these results, the authors propose 2 key strategies for increasing MVPA in adolescents: Increase the time spent in activity-supportive environments, such as parks and playgrounds, and design techniques to increase MVPA at home and school settings.

Is Greater Social Support from Parents and Friends Related to Higher Physical Activity Levels among Adolescents?

Increasing physical activity levels during adolescence have been put on the agenda by several researchers. This study verified the association between social support from parents and friends and different amounts of moderate-to-vigorous physical activity (MVPA) among adolescents in public school. The present study had a cross-sectional design and included a representative sample of 1984 adolescents (aged 15-17). The ASAFA (Apoio Social para prática de Atividade Física para Adolescentes) scale and the QAFA (Questionário de Atividade Física para Adolescentes) were used to determine social support and physical activity, respectively. For statistical analysis, a conceptual model for structured equations and weighted least squares mean and variance adjusted were applied. Social support from parents increased the odds of engaging in 180 min/week of MVPA by 46.7%, 47.8% for 300 min/week, and 45.5% for 420 min/week. Social support from friends showed similar relations trends: 23.8% for 180 min/week, 23.6% for 300 min/week, and 21.2% for 420 min/week. Social support from parents and friends increased the probability of adolescents reaching the amounts of physical activity investigated. The results indicate that greater social support (from parents and friends) was associated with a higher level of MVPA in Brazilian adolescents.

Do socioeconomic inequities arise during school-based physical activity interventions? An exploratory case study of the GoActive trial

ObjectiveTo investigate socioeconomic inequities in the intervention and evaluation process of the GoActive school-based physical activity intervention and demonstrate a novel approach to evaluating intervention-related inequalities.DesignExploratory post-hoc secondary data analysis...

Intrapersonal, interpersonal and environmental correlates of moderate to vigorous physical activity and sedentary time in adolescents with intellectual and developmental disabilities.

Although correlates of physical activity (PA) have been extensively examined in both children and adolescents who are typically developing, little is known about correlates of moderate to vigorous physical activity (MVPA) and sedentary time in adolescents with intellectual and developmental disabilities (IDD). Therefore, we examined intrapersonal, interpersonal and environmental factors and their association with device-based MVPA and sedentary time in adolescents with IDD. MVPA and sedentary time was assessed using a hip-worn ActiGraph model wGT3x-BT tri-axial accelerometer across a 7-day period in adolescents with IDD and one of their parents. Pearson and point-biserial correlations were calculated to inspect the associations of PA (MVPA, sedentary time) with intrapersonal factors (demographic characteristic, BMI, waist circumference, motor ability, muscle strength, grip strength, cardiovascular fitness and self-efficacy for PA), interpersonal factors (parent demographics, parent BMI, parent MVPA and sedentary time, family social support for PA, parent barriers and support for PA, parent's beliefs/attitudes towards PA and number of siblings), and environmental factors (meteorologic season and COVID-19). Ordinary least squares regression was used to estimate the unique contributions of key factors to PA after controlling for participants' age, sex, race, waist circumference and total wear time. Ninety-two adolescents (15.5±3.0years old, 21.7% non-White, 6.5% Hispanic, 56.5% female) provided valid accelerometer data. Average sedentary time was 494.6±136.4min/day and average MVPA was 19.8±24.2min/day. Age (r=0.27, P=0.01), diagnosis of congenital heart disease (r=-0.26, P=0.01) and parent sedentary time (r=0.30, P=0.01) were correlated with sedentary time. BMI (r=-0.24, P=0.03), waist circumference (r=-0.28, P=0.01), identifying as White (r=-0.23, P=0.03) and parent MVPA (r=0.56, P<0.001) were correlated with MVPA. After adjusting for the adolescent's age, sex, race, waist circumference, and total wear time, the association between parent and adolescent MVPA remained significant (b=0.55, P<0.01, partial η2 =0.11). The results of this study provide evidence that race, waist circumference and parental MVPA may influence the amount of MVPA in adolescents with IDD. The limited available information and the potential health benefits of increased MVPA highlight the need to evaluate the effectiveness of multi-component interventions targeting both intrapersonal and interpersonal levels to promote increased PA in adolescents with IDD.

Associations between parental reasons for choosing a neighborhood and adolescents’ physical activity and commuting behaviors

IntroductionAdolescents' physical activity (PA) and commuting behaviors are related to their parents' perceptions of the neighborhood. This study analyzed the association between parental reasons for choosing a neighborhood to live in and their adolescent’ moderate-to-vigorous PA (MVPA), active commuting to/from school (ACS), and independent mobility (IM) excluding school travel. MethodsParticipants were adolescents (n = 373) and their parents (n = 373) in Spain. Parents reported their reasons for choosing a neighborhood, and adolescents reported their ACS and IM excluding school travel. Accelerometry was used to assess adolescents’ MVPA. Multilevel regressions were used to analyze the associations between parental reasons and the outcome variables (MVPA, ACS and IM). ResultsHigh importance of affordability/value for parents was associated with higher levels of weekday MVPA in adolescents (β = 2.17, 95% confidence interval [CI] 0.21, 4.16), whereas greater distance from busy streets (β = 2.08, 95% CI 0.12, 4.51) was positively associated with MVPA during the weekend. A higher percentage of ACS in adolescents was associated with having parents who valued proximity to the school (β = 3.43, 95% CI 0.17, 0.64). IM excluding school travel was higher when parents assigned relatively less value to the proximity of the school (β = −3.35, 95% CI −8.76, −2.28), safety from crime (β = −2.77, 95% CI −6.63, −1.39), and sense of community (β = −2.31, 95% CI −6.63, −0.53). ConclusionsIt is crucial to develop spaces and facilities for PA, and to increase the walkability of the neighborhoods, considering the distance from home to school, in order to promote MVPA and ACS in adolescents.

Changes in physical activity across a 6-month weight loss intervention in adolescents with intellectual and developmental disabilities.

Adolescents and young adults with intellectual and developmental disabilities (IDD) have high rates of obesity and low levels of physical activity. This analysis examined changes in light, moderate-to-vigorous physical activity (MVPA) and sedentary time, and the association between changes in MVPA and weight loss in adolescents and young adults with IDD and overweight and obesity participating in a 6-month multi-component weight loss intervention. Adolescents and young adults with IDD and overweight or obesity (body mass index≥85 percentile, n=110, age ~16years, 52.7% female) and a parent were randomised to one of three intervention groups: face-to-face delivery/conventional reduced energy diet (n=36), remote delivery (RD)/conventional reduced energy diet (n=39), or RD/reduced energy enhanced stop light diet (eSLD) (n=35.) Participants were asked to engage in 60min/day of MVPA on 5 or more days/wk. Participants and a parent attended twice monthly education/behavioural counselling sessions with a health educator to assist participants in complying with dietary and MVPA recommendations. Education/counselling in the RD arms was delivered remotely using video conferencing, and self-monitoring of MVPA and daily steps was completed using a wireless activity tracker. Education/counselling in the face-to-face arm was delivered during home-visits and self-monitoring of MVPA and daily steps was completed by self-report using paper tracking forms designed for individuals with IDD. MVPA, light activity, and sedentary time were assessed over 7days at baseline and 6months using a portable accelerometer (ActiGraph wGT3x-BT). Mixed modelling analysis completed using participants with valid accelerometer data (i.e. ≥4-10h days) at baseline (n=68) and 6months (n=30) revealed no significant changes in light, moderate- MVPA, or sedentary time across the 6-month intervention (all P>0.05). Participants obtained 15.2±21.5min/day of MVPA at baseline and 19.7±19.7min/day at 6months (P=0.119). Mixed modelling indicated no significant effects of group (P=0.79), time (P=0.10), or group-by-time interaction (P=0.21) on changes in MVPA from baseline to 6months. Correlational analysis conducted on participants with valid accelerometer data at both baseline and 6months (n=24) revealed no significant associations between baseline sedentary time (r=0.10, P=0.40) and baseline MVPA (r=-0.22, P=0.30) and change in MVPA across the 6-month intervention. Additionally, attendance at education/counselling sessions (r=0.26, P=0.22) and frequency of self-monitoring of MVPA were not significantly associated with change in MVPA from baseline to 6months (r=0.26, P=0.44). Baseline MVPA (r=0.02, P=0.92) and change in MVPA from baseline to 6months (r=0.13, P=0.30) were not associated with changes in body weight across the 6-month intervention. We observed a non-significant increase in MVPA (30%), which was not associated with the magnitude of weight loss in a sample of adolescents and young adults with IDD who participated in a 6-month multi-component weight loss intervention. Additional strategies to increase MVPA in adolescents and young adults with IDD participating in weight loss interventions need to be developed and evaluated.

Psychological needs satisfaction, self-determined motivation, and physical activity of students in physical education: Comparison across gender and school levels

ABSTRACT This study applies self-determination theory (SDT) to test the hypothesised relationships amongst three basic psychological needs, level of self-determined motivation (i.e. self-determination index, SDI) and moderate-to-vigorous physical activity (MVPA) of Chinese elementary and secondary school students during their physical education (PE) in Shanghai, China. Gender and school-level differences in these relationships are also explored. The participants comprise 1829 students from three elementary and secondary schools in Shanghai, China. Accelerometers are used to measure the MVPA duration of the participants in PE. The Self-regulation Questionnaire and the Psychological Needs Satisfaction Scale are completed by the participants to assess PE motivation and the three psychological needs of students. The structural equation modelling (SEM) results show that the hypothesised model has a good fit with our data. Autonomy, competence, and relatedness are positively associated with SDI for MVPA. The SDI is positively related to the time spent by students in MVPA in PE. The multi-group path analysis results reveal that the relationship between SDI and MVPA is stronger for secondary school students than elementary students. Overall, our findings support the applicability of SDT in understanding and promoting the physical activities amongst Chinese school students in PE. Accordingly, intervention should be conducted to develop autonomy, competence and social relatedness of elementary and secondary school students. Additional efforts are required to encourage elementary school students to be more self-determinant in PE classes. Highlights Findings support the applicability of SDT in understanding and promoting the physical activities amongst Chinese school students in PE SDI was positively related to school students’ MVPA level. The satisfaction of autonomy, competence and relatedness towards PE was positively associated with students’ SDI. The proposed motivational sequence for adolescent MVPA in PE were similar for male and female students. The relationship between SDI and MVPA of secondary school students was significantly stronger than elementary school students

Association between physical activity and leisure-time sedentary behavior among 140,808 adolescents aged 12 to 15 from 47 low- and middle-income countries

ObjectivesData from high-income countries (HICs) indicate that sedentary behavior is negatively associated with moderate-to-vigorous physical activity (MVPA) in young people. We examined associations between leisure-time sedentary behavior (LTSB) and MVPA in adolescents from 47 low- and middle-income countries (LMICs). Study designCross-sectional study. MethodsData from the Global school-based Student Health Survey were analyzed in 140,808 adolescents (13.8 ± 1.0 years; 49% girls). Time spent in LTSB was a composite variable assessing time spent sitting and playing computer games, watching TV, talking with friends during a typical day. The PACE + Adolescent Physical Activity Measure assessed MVPA levels. The association between ≥3 h/day of LTSB and adequate physical activity levels (every day last week 60 min MVPA) was explored with multivariable logistic regression analyses. ResultsThe prevalence of ≥3 h/day of LTSB and 60 min of MVPA/day last week were 26.3% (girls 26.2%; boys 26.5%) and 15.3% (girls 12.1%; boys 18.4%), respectively. LTSB of ≥3 h/day versus <3 h/day was associated with a 35% increased odds for adequate levels of MVPA in boys [OR = 1.35 (95%CI = 1.23–1.48)] and 22% in girls [1.22 (95%CI = 1.10–1.36)]. ConclusionsOur data indicate that being physically active 60 min per day every day and at moderate-to-vigorous intensity and being sedentary ≥3 h/day during leisure-time might co-exist in adolescents in some LMICs.

Park environment and moderate-to-vigorous physical activity in parks among adolescents in a high-density city: the moderating role of neighbourhood income

BackgroundUrban parks are critical environmental resources in which adolescents engage in physical activity (PA). Evidence on the associations between park environmental characteristics and park-based PA in adolescents is mixed, particularly for high-density cities. Evidence is also lacking concerning the moderating role of neighbourhood socioeconomic status on the park-PA relationships. The current study aimed to examine the associations between park environmental characteristics and moderate-to-vigorous physical activity (MVPA) in parks among adolescents in Hong Kong and the moderating effect of neighbourhood income on these associations.MethodsA cross-sectional study involving direct observations of adolescents was conducted in 32 randomly selected urban parks in Hong Kong. Park environmental characteristics were measured using the Community Park Audit Tool. Park-based MVPA among adolescents was measured using the System for Observation Play and Recreation in Communities. Neighbourhood income was extracted from the 2011 Hong Kong Population Census data on median household income.ResultsThere was a significant positive association between the quality of amenities and park-based MVPA (metabolic equivalents per observation) in adolescents. However, the associations between the diversity of active facilities, greenness and adolescents’ park-based MVPA were not significant. Neighbourhood income moderated the association between adolescents’ park-based MVPA and park safety, where the relationship between park safety and park-based MVPA was significantly positive in low-income neighbourhoods but not significant in high-income neighbourhoods. An income-by-environment interaction was also observed concerning park aesthetics, with a negative relationship between park aesthetics and park-based MVPA in high-income neighbourhoods but not in low-income neighbourhoods.ConclusionOur findings provide evidence regarding how park environment and neighbourhood income impact adolescents’ park-based MVPA in Hong Kong. These findings can inform urban planning and policymakers who seek to improve urban park development in high-density cities.

Patterns of physical activity parenting practices among parent-adolescent dyads who participated in a cross-sectional internet-based study

BackgroundWhile research exploring relationships between individual parenting practices and child physical activity (PA) exists, little is known about simultaneous use of practices. Hence, study objectives were to determine patterns of PA parenting practices and their associations with demographic, anthropometric, and PA measures in a large sample of parents and their adolescent children (12–17 years).MethodsDyadic survey data from Family Life, Activity, Sun, Health, and Eating (FLASHE), a cross-sectional, internet-based study, conducted in 2014 were analyzed using latent class analysis on 5 PA parenting practices – pressuring, guided choice, expectations, facilitation, and modeling. Self-report model covariates included adolescent age and parent and adolescent sex, body mass index category (based on height and weight), legitimacy of parental authority regarding PA (PA-LPA), and moderate-to-vigorous PA (MVPA).ResultsBased on 1166 parent-adolescent dyads, four latent classes were identified representing a continuum of practice use (high to low) – Complete Influencers (26%), Facilitating-Modeling Influencers (23%), Pressuring-Expecting Influencers (25%), and Indifferent Influencers (27%). Compared to dyads with parent underweight/healthy weight, dyads with parent overweight/obesity had 84% higher odds of belonging to Indifferent Influencers. Compared to dyads with adolescent underweight/healthy weight, dyads with adolescent overweight/obesity had 50 and 46% lower odds of belonging to Facilitating-Modeling and Indifferent Influencers. Odds of belonging to Pressuring-Expecting and Indifferent Influencers were less than 1% lower for every 1 min/day increase in parent MVPA and 2 and 4% lower for every 1 min/day increase in adolescent MVPA. Compared to dyads with high parental and adolescent agreement with PA-LPA, dyads with low agreement had between 3 and 21 times the odds of belonging to Facilitating-Modeling, Pressuring-Expecting, or Indifferent Influencers.ConclusionsFindings suggest that parents utilize distinct patterns of PA practices ranging from use of many, use of some, to low use of any practice and these patterns are differentially associated with parent and adolescent PA. When planning PA interventions, a counseling or intervening approach with parents to use combinations of practices, like facilitation and modeling, to positively influence their adolescents’ and possibly their own participation in PA may prove more efficacious than parental pressuring or lack of practice use.

A national examination of neighborhood socio-economic disparities in built environment correlates of youth physical activity.

Adolescents in the U.S. do not meet current physical activity guidelines. Ecological models of physical activity posit that factors across multiple levels may support physical activity by promoting walkability, such as the neighborhood built environment and neighborhood socioeconomic status (nSES). We examined associations between neighborhood built environment factors and adolescent moderate-to-vigorous physical activity (MVPA), and whether nSES moderated associations. Data were drawn from a national sample of adolescents (12-17years, N=1295) surveyed in 2014. MVPA (minutes/week) were estimated from self-report validated by accelerometer data. Adolescents' home addresses were geocoded and linked to Census data from which a nSES Index and home neighborhood factors were derived using factor analysis (high density, older homes, short auto commutes). Multiple linear regression models examined associations between neighborhood factors and MVPA, and tested interactions between quintiles of nSES and each neighborhood factor, adjusting for socio-demographics. Living in higher density neighborhoods (B(SE): 9.22 (2.78), p=0.001) and neighborhoods with more older homes (4.42 (1.85), p=0.02) were positively associated with adolescent MVPA. Living in neighborhoods with shorter commute times was negatively associated with MVPA (-5.11 (2.34), p=0.03). Positive associations were found between MVPA and the high density and older homes neighborhood factors, though associations were not consistent across quintiles. In conclusion, living in neighborhoods with walkable attributes was associated with greater adolescent MVPA, though the effects were not distributed equally across nSES. Adolescents living in lower SES neighborhoods may benefit more from physical activity interventions and environmental supports that provide opportunities to be active beyond neighborhood walkability.

Psychological Stress and Lowered Physical Activity Enjoyment in Adolescents With Overweight/Obesity.

The purpose of this study was 2-fold: 1) to determine the cross-sectional associations between psychological stress, physical activity enjoyment, and physical activity participation [moderate-to-vigorous physical activity (MVPA), total physical activity (TPA)]; and 2) to determine the moderating effect of physical activity enjoyment on the associations between stress, MVPA, and TPA in adolescents with overweight/obesity. Cross-sectional, secondary data analysis of the Health and Culture Project and the Stress, Obesity, and Diabetes in Adolescents study. One hundred and ten adolescents (73% female; 65.4% non-white; age 15.8 ± 1.9 years) with overweight/obesity (BMI percentile ≥ 85th percentile) were included in this analysis. Psychological stress was assessed using the Perceived Stress Scale (PSS-14); enjoyment was measured via the Physical Activity Enjoyment Scale; and MVPA and TPA were objectively measured using accelerometry over a minimum of 4 days. Higher perceived stress was associated with lower physical activity enjoyment (β = -0.41 ± 0.15; p = 0.008). Stress was not associated with MVPA or TPA (ps > 0.05), nor was enjoyment a significant moderator in the associations between stress and MVPA or stress and TPA (pinteraction > 0.05). These findings suggest that psychological stress is associated with lower physical activity enjoyment among adolescents with overweight/obesity. Longitudinal studies are needed to understand the long-term effects of stress on psychological factors that may serve as antecedents to physical activity participation among adolescents with overweight/obesity.

Environmental factors and physical activity among youth in rural Japan: a 1-year prospective study

Abstract Background Although moderate-to-vigorous physical activity (MVPA) has multiple health benefits, current global activity levels among children are quite low. Environmental influences on MVPA levels among children and adolescents in rural areas are unclear. The present study examined if environmental factors were associated with MVPA in children and adolescents in rural Japan. Methods Two school-based serial surveys were conducted in 2017 and 2018 for 1,461 children and adolescents (10-14 years old) in Unnan City, Japan. If meeting the WHO recommended MVPA levels: at least 60 minutes/day was assessed via the Japanese translation of the WHO Health Behaviour in School-aged Children survey questionnaire. Environmental factors, namely habitable land area, population size, and population density were calculated for each individuals' residential town, and categorized into three levels (small, medium, and large). Logistic regression was used to determine odds ratios (OR) and 95% confidence intervals (CI) of engaging in the recommended level of MVPA after 1 year by each environmental factor, adjusting for sex, school grades, body mass index, screen time, preference for PA, and MVPA level at baseline. Results Only 22.4% of children and adolescents were engaging in the recommended MVPA levels in 2018. Engaging in the recommended level of MVPA after 1 year was significantly associated with medium (OR = 1.63; 95%CI, 1.08-2.46) and large (OR = 1.69; 95%CI, 1.15-2.47) compared to small habitable areas, and with medium (OR = 1.01; 95%CI, 0.61-1.67) and large (OR = 1.75; 95%CI, 1.09-2.81) compared to small population size. Population density was not associated with MVPA. Conclusions This prospective study found that habitable area and population size were positively associated with MVPA at 1-year follow-up in rural Japan. In rural areas, habitable land areas and population size itself may be a better predictor for MVPA among children than population density. Key messages Habitable area and population size was positively associated with physical activity among children and adolescents in rural Japan. Population density as an environmental factor was not associated with physical activity.

Abstract C013: Neighborhood socioeconomic status but not individual self-efficacy moderates associations between neighborhood walkability and adolescent physical activity in the NCI geoFLASHE Study

Abstract Neighborhood walkability, socioeconomic status (SES) and psychosocial factors have each been associated with physical activity. Yet few U.S. studies have examined whether neighborhood SES or individual factors moderate associations between neighborhood walkability and adolescent physical activity levels. Adolescent data (n=1,288) from the NCI Family Life, Activity, Sun and Healthy Eating (FLASHE) study was used. Minutes per day of moderate to vigorous physical activity (MVPA) were calculated using the self-reported Youth Activity Profile and a subsample of participant accelerometer data. Adolescent home address was geocoded and linked to U.S. Census data at varying street network buffer sizes. Neighborhoods were defined by a 400m buffer around each participant's home. Factor analysis of neighborhood population density and built environment features revealed three neighborhood factors associated with walkability: 1) high density and non-auto commutes, 2) older homes, and 3) short auto commutes. Neighborhood SES was measured using the Yost index derived from Census data and categorized into quintiles (1 = lowest SES; 5 = highest SES). Multiple linear regression examined associations between neighborhood walkability factors and adolescent MVPA, and interactions between these factors and 1) neighborhood SES and 2) physical activity self-efficacy. We controlled for age, gender, race/ethnicity, and parent education. Living in neighborhoods with higher density (B=7.3, p=0.003) and older homes (B= 4.7, p=0.007) were positively associated with MVPA. The positive association between living in a higher density neighborhood with more non-auto commutes and MVPA was stronger for those living in neighborhoods at the 2nd and 4th quintiles of neighborhood SES, compared with those in the lowest SES neighborhoods. Similarly, the association between living in a neighborhood with older homes and MVPA was stronger for those living in the 2nd SES quintile compared with the lowest SES. Physical activity self-efficacy was independently positively associated with MVPA (B=18.9, p&amp;lt;.0.001), but did not moderate associations between walkability and MVPA. Neighborhood factors associated with walkability were associated with adolescent MVPA in this national sample of U.S. adolescents. For adolescents living in some higher SES neighborhoods, the association between living in a high-density or older neighborhood and MVPA was strengthened, suggesting that the walkability experience, or types of physical activities engaged in, may potentially vary by neighborhood SES, and are independent of individual self-efficacy. Citation Format: Heather D'Angelo, Laura Dwyer, Linda Nebeling, April Oh. Neighborhood socioeconomic status but not individual self-efficacy moderates associations between neighborhood walkability and adolescent physical activity in the NCI geoFLASHE Study [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C013.

The Effects of Parental Stress on Physical Activity Among Overweight and Obese Hispanic Adolescents: Moderating Role of Family Communication and Gender.

Previous literature has shown a negative relationship between parental stress and youth moderate to vigorous physical activity (MVPA). This study examined (1)the relationship between parental stress and adolescent MVPA, (2)the moderating role of family communication on this relationship, and (3)gender differences in these effects among overweight and obese Hispanic adolescents. Hispanic adolescents (N = 280, 52% female, 13.0 [0.8]y old, 44% obese, 12% severely obese) and their parents (88% female, 44.9 [6.5]y old) completed baseline measures for an efficacy trial. Adolescents self-reported MVPA in minutes per week for work, transportation, and recreation using a validated measure. Multiple regression analyses with interaction terms and multigroup methods were conducted. There was a negative effect of parental stress on adolescent MVPA (β = -0.15, t = -2.018, P ≤ .05). This effect was moderated by family communication (β = 0.20, t = 2.471, P = .01), such that the association between parental stress and youth MVPA was stronger for adolescents with low levels of family communication. Furthermore, a multiple group model showed that the interaction was significant for boys (β = 0.27, t = 2.185, P = .03), but not for girls. Findings provide support that addressing parental stress and family communication may help facilitate MVPA among Hispanic boys, the most at-risk group for pediatric obesity.

Perceived Controlling Behaviors of Physical Education Teachers and Objectively Measured Leisure-Time Physical Activity in Adolescents.

The facilitative role of perceived autonomy support from physical education (PE) teachers on adolescents’ leisure-time physical activity (PA) has been supported. This study aimed to examine the mechanism by which perceived controlling behaviors from PE teachers relate to adolescents’ objectively measured leisure-time PA. In a three-wave prospective study, a total of 159 students (64 boys) aged 11 to 19 years old (Mage = 14.94 years; SD = 2.11) completed measures of perceived controlling behavior, frustration of the basic psychological needs, and motivational regulations in PE. One week later, motivational regulations towards leisure-time moderate-to-vigorous PA (MVPA) were assessed. Five weeks later, MVPA was measured using accelerometers (ActiGraph GT3X) during seven consecutive days. Structural equation modeling analysis indicated that perceived controlling behavior predicted students’ frustration of basic psychological needs in PE. The competence need frustration in PE had a negative direct effect on objectively measured MVPA. A significant indirect effect supported the mediating role of competence frustration in PE in the relation between perceived controlling behavior from PE teachers and MVPA in adolescents. Findings suggest that future interventions striving to promote adolescents’ PA engagement in their leisure-time should focus on decreasing controlling behaviors from teachers in PE that may manipulate the teacher–student relation.

Individual and family-based approaches to increase physical activity in adolescents with intellectual and developmental disabilities: Rationale and design for an 18 month randomized trial

Adolescents with intellectual and developmental disabilities (IDD) are less physically active and have lower cardiovascular fitness compared with their typically developing peers. This population faces additional barriers to participation in moderate-to-vigorous physical activity (MVPA) such as reliance on parents, lack of peer-support, and lack of inclusive physical activity opportunities. Previous interventions to increase MVPA in adolescents with IDD have met with limited success, at least in part due to requiring parents to transport their adolescent to an exercise facility. We recently developed a remote system to deliver MVPA to groups of adolescents with IDD in their homes via video conferencing on a tablet computer. This approach eliminates the need for transportation and provides social interaction and support from both a health coach and other participants. We will conduct a 18-mo. trial (6 mos. active, 6 mos. maintenance, 6 mos. no-contact follow-up) to compare changes in objectively assessed MVPA in 114 adolescents with IDD randomized to a single level intervention delivered only to the adolescent (AO) or a multi-level intervention delivered to both the adolescent and a parent (A + P). Our primary aim is to compare increases in MVPA (min/d) between the AO and A + P groups from 0 to 6 mos. Secondarily we will compare changes in MVPA, sedentary time, cardiovascular fitness, muscular strength, motor ability, quality of life, and the percentage of adolescents achieving the US recommendation of 60 min. MVPA/d across 18 mos. We will also explore the influence of process variables/participant characteristics on changes in MVPA across 18 mos.NCT registration: NCT03684512

Association of moderate-to-vigorous physical activity with neck circumference in eight Latin American countries

BackgroundPhysical activity is a cornerstone in the prevention and treatment of obesity. There are relatively few studies that explore the effect of accelerometer-determined moderate-to-vigorous physical activity (MVPA) on neck circumference (NC), most of them confined to single high-income countries. The present study investigated the association of accelerometer-determined MVPA with NC in adolescents and adults from eight Latin American countries, which are mostly upper-middle income countries.MethodsThe sample consisted of 2370 participants (47.8% male) from the Latin American Study of Nutrition and Health, a multicenter cross-sectional nutrition and health surveillance study of a nationally representative sample from eight Latin American countries (Argentina, Brazil, Chile, Colombia, Costa Rica, Ecuador, Peru, and Venezuela). Times (min/day) in MVPA (defined as time accumulated at ≥1952 activity counts/min) was assessed by ActiGraph GT3X+ accelerometer over 7 days. NC for adolescent was categorized as abnormal if circumference was > 34.5 cm for boys and > 31.25 for girls, whereas for adults the cut-off points for abnormal were > 39 cm for men and > 35 cm women. Multilevel logistic models, including country and region as random effects and adjusted for sex, age, socioeconomic level, and educational level, were used to study the association between MVPA and NC.ResultsThe average time of MVPA was 34.88 min/day, ranging from 31.16 in Venezuela to 40.27 in Chile. Concerning NC, 37.0% of the sample was classified as having elevated NC. Chile was the country with the highest percentage of people with elevated NC (56.9%), and Colombia had the lowest percentage (24.8%). Overall, the MVPA (min/day) was associated with elevated NC (OR = 0.994, CI95% = 0.990–0.998). In Costa Rica and Peru, there were significant associations between MVPA and NC when analyzed by country.ConclusionsThe present study provided evidence of significant associations between MVPA and NC in adolescents and adults from Latin America, independent of sex, age, socioeconomic level, and educational level. This analysis of accelerometry data and NC represents the first examination of these associations in eight Latin America countries. Further research is required to understand the differences between countries in the observed associations.Trial registrationClinicalTrials.Gov NCT02226627. Retrospectively registered on August 27, 2014.

Active Transport, Not Device Use, Associates with Self-Reported School Week Physical Activity in Adolescents.

The purpose of this study was to examine the relationships among active transport, electronic device-use, and self-reported school week moderate-to-vigorous physical activity (MVPA) in a sample of adolescents. The sample consisted of 1445 adolescents enrolled in the Family Life, Activity, Sun, Health, and Eating study. A panel research organization invited panel members balanced to the US population on sex, census division, household income and size, and race/ethnicity. Web-based surveys were administered to each selected adolescent. Adolescents answered questions pertaining to out-of-school electronic device-use and active transport to and from school. Predicted weekly minutes of MVPA were calculated from the Youth Activity Profile. The outcome variable was predicted school week MVPA (in minutes). The predictive utility of device-use and active transport variables on self-reported school week MVPA were examined using weighted multiple linear regression models. After adjusting for age, sex, and BMI, active transport to school (b = 12.32, 95% CI [9.72–14.93], p < 0.001) and from school (b = 7.18, 95% CI [4.79–5.57], p < 0.001) were significantly associated with self-reported school week MVPA. No device-use variables were significantly associated with school week MVPA. Active transport to and from school may have an impact on school week MVPA in adolescents.

Association of Age, Sex, and Weight with Moderate-to-Vigorous Physical Activity in a Pediatric Type 1 Diabetes Population

Current guidelines from the ADA recommend that children and adolescents with T1D engage in at least 60 minutes of moderate-to-vigorous physical activity (MVPA) every day. However, subjectivity of MVPA reporting methods and short study durations compromise the applicability of existing data; there is not a clear picture of MVPA in this population. Therefore, objective measures of MVPA in children and adolescents with T1D are necessary to better understand the importance of other factors related to MVPA like sex, age, and weight. In a prospective cohort of 1children and adolescents with T1D, physical activity was objectively monitored for 6 months using commercially available activity monitors. Weekly MVPA was summarized as the average number of hours of MVPA for weeks with valid activity monitor use. Regular weekly MVPA in children and adolescents was described by age, sex, and weight. The Mann-Whitney U test was used to assess associations. In the study population, we observed an average (SD) weekly MVPA of 2.4 (1.7) hours and median (Q1, Q3) weekly MVPA of 1.9 (0.9, 3.0) hours. Sex was significantly associated with MVPA (p&amp;lt;0.0001) with average (SD) weekly MVPA of 3.5 (2.4) hours for males and 1.4 (1.0) hours for females. There was no significant difference in weekly MVPA between children (8-12 years) and adolescents (13-17 years). Interestingly, overweight children (BMI z-score above 85th percentile) were more active than non-overweight children (average weekly MVPA of 3.0 and 2.1 hours respectively), however this difference was not statistically significant. This study presents data on MVPA in children and adolescents with T1D over a long duration using objectively measured physical activity. Our results suggest that sex is an important factor associated with MVPA and that over 75% of children in this population do not regularly meet the ADA MVPA recommendations. Disclosure N.E. Thompson: None. D.A. Watson: None. T.L. Barnes: None. L.M. Gandrud: Consultant; Self; UnitedHealth Group.