A systematic review of the clustering and correlates of physical activity and sedentary behavior among boys and girls.

Identifying the clustering and correlates of physical activity (PA) and sedentary behavior (SB) is very important for developing appropriate lifestyle interventions for children and adolescents. This systematic review (Prospero CRD42018094826) aimed to identify PA and SB cluster patterns and their correlates among boys and girls (0-19 years). The search was carried out in five electronic databases. Cluster characteristics were extracted in accordance with authors' descriptions by two independent reviewers and a third resolved any disagreements. Seventeen studies met the inclusion criteria and the population age ranged from six to 18 years old. Nine, twelve, and ten cluster types were identified for mixed-sex samples, boys, and girls, respectively. While girls were in clusters characterized by "Low PA Low SB" and "Low PA High SB", the majority of boys were in clusters defined by "High PA High SB" and "High PA Low SB". Few associations were found between sociodemographic variables and all cluster types. Boys and girls in "High PA High SB" clusters had higher BMI and obesity in most of the tested associations. In contrast, those in the "High PA Low SB" clusters presented lower BMI, waist circumference, and overweight and obesity. Different cluster patterns of PA and SB were observed in boys and girls. However, in both sexes, a better adiposity profile was found among children and adolescents in "High PA Low SB" clusters. Our results suggest that it is not enough to increase PA to manage the adiposity correlates, it is also necessary to reduce SB in this population.

Bidirectional Daily Associations Between Accelerometer-Measured Sleep and Physical Activity in Brazilian High School Students.

PURPOSE: This study analyzed day-to-day estimates of bidirectional associations between sleep parameters and intensity-specific physical activity and assessed whether the timing of physical activity influences these relationships. METHODS: The sample was comprised of 651 high school students (51.2% female, 16.33 [1.0] y old) from southern Brazil. Physical activity and sleep were measured using accelerometers. Multilevel models were applied to test associations of nocturnal total sleep time, onset, and efficiency with moderate to vigorous and light (LPA) physical activity. RESULTS: Higher engagement in moderate to vigorous physical activity and LPA was associated with increased total sleep time, and this effect was greater when physical activity was performed in the morning. Morning and evening LPA were associated with increased sleep efficiency and reduced total sleep time, respectively. Practice of LPA in the morning leads to early sleep onset, whereas evening LPA was associated with later onset. Higher total sleep time and later sleep onset were associated with lower moderate to vigorous physical activity and LPA on the following day. However, higher sleep efficiency was associated with increased LPA. CONCLUSION: The relationship between sleep parameters and physical activity is bidirectional and dependent on physical activity intensity and timing.

Mapping recommended strategies to promote active and healthy lifestyles through physical education classes: a scoping review.

BACKGROUND: Understanding which strategies have been recommended for the promotion of active and healthy lifestyles through physical education (PE) classes can guide PE policies and practice. Therefore, we summarized worldwide recommendations regarding strategies for PE classes that have aimed to promote active and healthy lifestyles among school-aged children and adolescents. METHODS: The Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR) guidelines were utilized. A literature search was carried out in June 2020 in eight peer-reviewed literature databases, in addition to searches in institutional and personal libraries. The eligibility criteria included any online document that included recommendations targeting any dimension of PE classes (e.g., policy and environment, curriculum, appropriate instruction, student assessment, and strategies that interact with PE) published since 2000. RESULTS: In total, 2,408 potentially eligible documents were screened. Of these, 63 were included in the final analysis. The recommended strategies were as follows: six referred to policy and environment (valuing PE, higher frequency and duration of classes, inclusive PE classes, mandatory daily classes, evaluation of PE classes, and qualified teachers), five to curriculum (structure, type of content, cross-cutting themes, and components that improve PE classes), four to appropriate instruction (promotion of physical activities, inclusion of social issues, employment of the use of innovative technologies, and organization of the teaching-learning process), and three to student assessment (understanding human movement concepts, evaluation of contents, and assessment methods to develop an active and healthy lifestyle). CONCLUSION: Twenty-one strategies recommended for PE classes linked to five dimensions aimed at different target populations were identified. Over half were linked to the dimensions of policy and environment and appropriate instruction. PE is recommended to be mandatory and valued at all educational levels, with weekly frequency that contributes to an active and healthy lifestyle. This review shows that guaranteeing different experiences beyond sports, improving social inclusion, using innovative technologies, and providing adequate materials and spaces to be important challenges and ways to guide policies, programs, and new research in this field of knowledge. Open Science Framework Registration: https://osf.io/harwq/.

Clustering of Physical Activity, Sleep, Diet, and Screen-Based Device Use Associated with Self-Rated Health in Adolescents.

BACKGROUND: Little is known about how the interplay among health-related behaviors impacts self-rated health (SRH). We examined the clustering of physical activity (PA), sleep, diet, and specific screen-based device use, and the associations between the emergent clusters and SRH among Brazilian adolescents. METHOD: The data used in this cross-sectional study were from the baseline of the Movimente Program. Self-reported data were analyzed. SRH was recorded as a 5-point scale (from poor to excellent). Daily duration of exposure to the computer, the television, the cell phone, and games; PA; sleep; and weekly consumption of fruits and vegetables and ultra-processed foods were included in a Two-Step cluster analysis. Multilevel ordered logistic regressions assessed the associations between the clusters and SRH. RESULTS: The data of 750 students (girls: 52.8%, 13.1 ± 1.0 years) were analyzed. Good SRH was more prevalent (52.8%). Three clusters were identified: the Phubbers (50.53%; characterized by the longest cell phone use duration, shortest gaming and computer use, lowest PA levels, and low consumption of fruits and vegetables), the Gamers (22.80%; longest gaming and computer use duration, PA < sample average, highest intake of ultra-processed foods), and a Healthier cluster (26.67%; physically active, use of all screen-based devices < sample average, and healthier dietary patterns). For both Gamers (-0.85; 95% CI -1.24, -0.46) and Phubbers (-0.71; 95% CI -1.04, -0.38), it was found a decrease in the log-odds of being in a higher SRH category compared with the Healthier cluster. CONCLUSION: Specific clusters represent increased health-related risk. Assuming the interdependence of health-related behaviors is indispensable for accurately managing health promotion actions for distinguishable groups.

Implementation of a school-based physical activity intervention for Brazilian adolescents: a mixed-methods evaluation.

The effectiveness of physical activity interventions can be improved through examining the aspects related to their implementation. However, little such evidence has been collected, particularly in low- and middle-income countries. This study aimed to evaluate the implementation of a school-based physical activity intervention with qualitative and quantitative data from different actors (students, teachers and parents) involved in developing the program. The program was conducted in 2017 with three main components: (i) teacher training, (ii) environmental changes and (iii) educational actions. Mixed-method evaluation was performed by an independent evaluation team using a validated indicator matrix for the implementation process, including the self-reported information of students, teachers and parents, as well as interviews with teachers. In the 3 eligible schools, 350 adolescents (51% girls) answered the implementation questionnaire, as did 45 parents (84% mothers), and 47 teachers (70% female). In the qualitative analysis, 18 teachers participated. Categorical analysis found that the intervention was considered feasible by teachers. In general, teachers had a more positive perception of the implementation than did students. The lack of engagement from the school community and parents and the busy schedule of teachers were indicated to be the main difficulties. In conclusion, despite the teachers' motivation, some barriers prevented the successful implementation of the program.

Psychometric analysis of the Brazilian-version Kidscreen-27 questionnaire.

BACKGROUND: The objective of this study was to verify the reliability, discriminatory power and construct validity of the Kidscreen-27 questionnaire in Brazilian adolescents. METHODS: Adolescents that participated of the pilot study (210 adolescents; 52.9% boys; 13.7 years old) and of the baseline (816 participants; 52.7% girls; 13.1 years old) of the Movimente Project in 2016/2017 composed the sample of the present study. This project was carried out in six public schools in the city of Florianópolis, Santa Catarina, Brazil. Test-retest reproducibility was assessed by the intraclass correlation coefficient and Gwet coefficient; internal consistency through McDonald's Omega; Hankins' Delta G coefficient verified the scale's discriminatory power and; confirmatory factor analysis to assess construct validity. RESULTS: Reproducibility values ranged from 0.71 to 0.78 for the dimensions (ICC), and ranged from 0.60 to 0.83 for the items (Gwet). McDonald's Ômega (0.82-0.91) for internal consistency measures. Discriminatory power ranging from 0.94 for the dimension Social Support and Friends to 0.98 for Psychological Well-Being. The factorial loads were > 0.40, except for item 19 (0.36). The fit quality indicators of the model were adequate (X2[df] = 1022.89 [311], p < 0.001; RMSEA = 0.053 (0.049-0.087); CFI = 0.988; TLI = 0.987), confirming the five-factor structure originally proposed. CONCLUSIONS: The Brazilian-version Kidscreen-27 achieved good levels of reproducibility, internal consistency, discriminatory power and construct validity. Its use is adequate to measure the health-related quality of life of adolescents in the Brazilian context.

Association between sociodemographic, dietary, and substance use factors and accelerometer-measured 24-hour movement behaviours in Brazilian adolescents.

Sociodemographic factors and lifestyle behaviours were evidenced as correlates of self-reported 24-hour movement behaviours in high-income settings. However, it is unclear how these relations occur in a middle-income country setting, with unique cultural and social characteristics. This study aimed to examine the association between sociodemographic, dietary, and substance use factors with accelerometer-measured 24-hour movement behaviours in Brazilian adolescents. Information on sex, age, socioeconomic status (SES), family structure, dietary behaviours, and history of substance use were collected by a questionnaire. Sleep duration, sedentary behaviour, and light- and moderate-to-vigorous physical activity (LPA and MVPA) were measured using wrist-worn accelerometers. On average, females slept more (ß = 21.09, 95%CI 13.18; 28.98), engaged in more LPA (ß = 17.60, 95%CI 8.50; 27.13), and engaged in less sedentary behaviour (ß = -16.82, 95%CI -30.01; -4.30) and MVPA (ß = -4.76, 95%CI -7.48; -1.96) than males. Age and sedentary behaviour were positively associated (ß = 8.60, 95%CI 2.53; 14.64). Unprocessed foods were positively related to LPA (ß = 2.21, 95%CI 0.55; 3.92), whereas processed foods were positively related to sedentary behaviour (ß = 3.73, 95%CI 0.03; 7.38) and inversely related to MVPA (ß = -0.89, 95%CI -1.68; -0.10). Family structure, SES, and substance use factors were not significantly associated with any 24-hour movement behaviour.Conclusions: Sex, age, and dietary behaviours, unlike SES or substance use, were associated with 24-hour movement behaviours in this sample of Brazilian adolescents and are important factors to consider in interventions, policies, and practice. What is Known: • The 24-hour movement behaviours are composed of sleep, sedentary behaviour, and physical activity and are important determinants of health. • Most adolescents do not engage in adequate levels of physical activity, sedentary behaviour, and sleep, and there is a need to better understand factors related to these behaviours. What is New: • Sex, age, and dietary behaviours were associated with the 24-hour movement behaviours. • No associations were found between socioeconomic status and substance use with the 24-hour movement behaviours.

Effectiveness and moderators of a multicomponent school-based intervention on screen time devices: the Movimente cluster-randomized controlled trial.

BACKGROUND: Interventions targeting reduce screen time in adolescents are urgently needed, mainly in low and middle-income countries because of the lack of evidence. Thus, the aims of the study were to examine the effect of a cluster-randomized controlled trial on screen time (ST) devices among Brazilian adolescents and to identify possible moderators. METHODS: Movimente was a multicomponent school-based intervention that was performed in 2017 and consisted of teacher training, education curriculum, and environmental improvements. Baseline and post-intervention assessments (over one academic year) were conducted with students aged 10-16 years at baseline (baseline n = 921, [n = 538 intervention group; n = 383 control group]). A self-report questionnaire was used to measure daily minutes of device specific screen time (TV, computer, video games and smartphone) and demographic variables. Linear mixed models were used to examine intervention effects and an exploratory moderation analysis (sex, grade and socioeconomic status) was performed. RESULTS: The intervention had no significant effects on TV time (ß = - 6.4, 95% CI: - 6.1;13.4), game time (ß = - 8.2, 95% CI: - 7.2;10.8), computer time (ß = 1.1, 95% CI: - 6.3;18.5), smartphone time (ß = - 10.2, 95% CI: - 32.5;12.1), screen time (ß = - 12.8, 95% CI: - 50.5;24.8), meeting screen time guidelines (OR: 1.29, 95% CI: 0.65,2.57) and meeting screen time guidelines with smartphone (OR: 1.66, 95% CI: 0.37,7.40). There was a significant intervention effect on reducing TV time (ß = - 37.1, 95% CI: - 73.0, - 1.3) among 8th grade students only. CONCLUSIONS: The Movimente intervention was effective only for TV time among 8th grade students. Understanding how school-based interventions can improve adolescents' device specific screen time across age groups is needed. Future strategies should cover all screen-based devices. Further, there is a need for more studies in low- and-middle income countries to assist in the development of effective strategies. TRIAL REGISTRATION: Clinicaltrials.gov identifier NCT02944318 (25/10/2016).

Physical inactivity, television time and chronic diseases in Brazilian adults and older adults.

This study aimed to investigate the association between simultaneity of leisure-time physical inactivity and high television time with the presence of chronic diseases in adults and older adults in Brazil. We analyzed secondary data from Vigitel 2013 database, a cross-sectional national survey. It was included 37 947 adults (18-59 years) and 14 982 older adults (≥60 years) living in Brazilian state capitals. The association was between simultaneity of risk behaviors considering leisure-time physical inactivity (<10 min/day) and high television time (≥2 h/day), with the presence of chronic diseases (diabetes, dyslipidemia, hypertension and obesity), measured according to the age group. We performed a binary logistic regression, crude and adjusted analysis, using weighted to reflect population estimates. In adults, there was an association between leisure-time physical inactivity and television time with the presence of diseases. In practice, the simultaneity of risk behaviors when compared with those without risk behavior had higher odds for diabetes (OR = 1.83), dyslipidemia (OR = 1.17), hypertension (OR = 1.54) and obesity (OR = 1.60). In older adults, the simultaneity was associated with diabetes (OR = 1.61), hypertension (OR = 1.33) and obesity (OR = 1.81). We concluded that for adults and older adults the simultaneity of leisure-time physical inactivity and high television time increased the odds for the presence of chronic disease, especially for diabetes and obesity.

Is the availability of open public spaces associated with leisure-time physical activity in Brazilian adults?

This study aims to analyse the association between perceived presence of public spaces near residences and practice of physical activity during leisure time by adults in the state capitals of Brazil, based on sociodemographic characteristics. Participants were individuals aged ≥18 years living in the 27 state capitals of Brazil (n = 52 929, 53.9% female) who responded to a national survey called VIGITEL in 2013. Physical activity during leisure time (≥1 time/week), perception of space, population and sociodemographic variables (sex, age, years of study and geographic region) were self-reported. The adjusted binary logistic regression analysis was used. Among adults, the prevalence of physical activity during leisure was 45.1% (95% CI [44.2; 46.0]), and 71.1% (95% CI [70.2, 71.8]) perceived public space near their residence. A direct association between perceiving public space and physical activity ([OR] = 1.43; 95% CI [1.32; 1.55]) was observed. No significant difference was observed in the population groups (men and women, younger and older adults, and those with more and fewer years of study). Thus, even with the possible regional differences in Brazilian state capitals, the presence of public spaces increases the practice of physical activity during leisure time, independent of sociodemographic variables.

Mediating role of screen media use on adolescents' total sleep time: A cluster-randomized controlled trial for physical activity and sedentary behaviour.

BACKGROUND: The present study aimed to analyse the effect of an intervention for increasing physical activity (PA) and reducing sedentary time on adolescents' total sleep time (TST) and to examine whether the effect on adolescents' TST was mediated by the intervention changes on screen-based sedentary time. METHODS: This study was a school-based cluster-randomized controlled trial conducted with Brazilian adolescents in Grades 7 to 9 (in 2017). Three schools participated in each of the intervention group (IG) and control group (CG). The intervention involved the following three strategies designed to increase PA and reduce sedentary time: (a) teacher training, (b) environmental improvements, and (c) health educational component. TST and screen-based sedentary time (television use, cell phone use, playing on computer/video game, and computer use that is not for gaming purposes) on weekdays and weekends were assessed using a standardized questionnaire. Generalized linear mixed models were conducted to verify the effect of the intervention on TST. Mediation analyses were used to examine the mediator role of changes in screen-based sedentary time in the relationship between the intervention and TST. RESULTS: Overall, 597 students participated in this study (mean age: 13.0 ± 1.0 years; IG: n = 351; CG: n = 246). The intervention had no effect on TST on weekdays and weekends. Adolescents in the IG were more likely to report ≤2 hr of television viewing per day on weekdays at follow-up. Mediated effects by screen media use were not significant. CONCLUSIONS: The school-based intervention for increasing PA and reducing sedentary time had no effect on adolescents' TST.

Association between socio-economic status and physical activity is mediated by social support in Brazilian students.

This study evaluated whether the relationship between socioeconomic status (SES) and moderate-to-vigorous physical activity (MVPA) is mediated by social support of peers and parents. A cross-sectional study included students (n = 1182) aged 11 to 18 years who were recruited in 2014 from public schools in Fortaleza, Brazil. Participants completed a questionnaire to assess all variables. Mediation analyses were performed to determine the role of parental support and peer support on the relationship between SES and MVPA. Also, moderated-mediation analyses with estimating of conditional indirect effects were performed in order to identify whether gender is a moderator of the mediating effect. A positive and significant association between SES and MVPA was found among Brazilian students, and social support of parents and peers were significant mediators of this relationship. Conditional indirect effects showed that both parental and peer support had a significant indirect effect among boys; only parental support had a significant indirect effect among girls. These results suggest that improving social support can help reduce the impact of SES on physical activity among Brazilian adolescents.

Are adolescents really being sedentary or inactive when at school? An analysis of sedentary behaviour and physical activity bouts.

This study analysed physical activity (PA) and sedentary behaviour (SB) performed in bouts during schooltime. Adolescents of two schools answered a questionnaire, had their height and weight measured and wore accelerometers during schooltime. Moderate-to-vigorous intensity PA was estimated in bouts of 2, 5 and 10 min, and SB in bouts of 5, 10, 30 and 60 min. Body mass index was calculated, and adolescents were classified as overweight or normal weight. Frequency, duration and volume of PA and SB were calculated for the whole sample and for those who performed at least one bout weekly. PA and SB differences between gender and weight status were tested using Mann-Whitney and t tests. A total of 415 adolescents (54% girls, 12.3 ± 1.3 years old, 34.6% overweight) performed 0.1 (± 0.2), 0.2 (± 0.5) and 0.4 (± 0.6) bouts of 10, 5 and 2 min of PA, and 10.6 (± 2.0), 6.0 (± 1.3), 1.1 (± 0.9) and 0.4 (± 0.5) bouts/day of 5, 10, 30 and 60 min of SB, respectively. Boys accumulated less SB and more PA in bouts. No differences were found for weight status.Conclusion: Adolescents hardly engaged in bouted PA and accumulated more SB in smaller bouts during schooltime. Bouted PA and SB were not associated with weight status. What is Known: • Adolescents are not engaging in enough PA and are accumulating large volumes of SB, which might negatively impact their health. • Schools play an important role in daily overall PA, with opportunities such as PE classes and recesses. But most classes are still undertaken in seated positions. What is New: • Adolescents hardly engage in bouted (> 10 m) PA when at school., and most SB is accumulated in short bouts (≤ 10m). • Weight status was not associated with bouted PA or SB at school.

Clustering of diet, physical activity and sedentary behavior among Brazilian adolescents in the national school - based health survey (PeNSE 2015).

BACKGROUND: There is a lack of evidence regarding clusters of health-related behaviors among adolescents from low, lower-middle, and upper-middle income countries. This study aimed to identify clustering patterns of health-related behaviors (diet, physical activity [PA] and sedentary behavior [SB]) and association with sociodemographic variables among a population-based sample of Brazilian adolescents. METHODS: Cross-sectional data from the 2015 National School-Based Health Survey (PeNSE). A total of 102,072 (females: 51.7%) students in ninth-grade (age: 14.3 ± 1.1 years-old) enrolled in public and private schools were investigated in this study. Healthy and unhealthy diet, PA and SB were measured using a validated questionnaire. Two-step cluster analysis was conducted to identify lifestyle patterns. The methodology for complex analysis and weighting was used to inferential statistical procedures. Multinomial logistic regression assessed associations between sociodemographic factors and the clusters. RESULTS: Three reliable and meaningful clusters were identified and labelled as follows: (1) health-promoting SB and diet (32.6%); (2) health-promoting PA and diet (44.9%), and (3) health-risk (22.5%). Compared to boys, girls were less likely to be in clusters 1 (OR = 0.85; 95% CI = 0.78-0.93, p < 0.001) and 2 (OR = 0.43; 95% CI = 0.40-0.46, p < 0.001) than the health-risk cluster. Higher socioeconomic status was positively associated with health-promoting PA and diet, and negatively related to health-promoting SB and diet. Older adolescents were more likely to be in cluster 1 than in cluster 3, compared to younger adolescents. CONCLUSION: Approximately one-quarter of the population (health-risk cluster) reported engaging in multiple risk behaviors. Interventions may need to be tailored to specific adolescent groups, especially considering sociodemographic differences.

Physical activity as part of daily living: Moving beyond quantitative recommendations.

The purpose of this study is to discuss a paradigm shift towards a broader understanding of physical activity (PA) as part of daily living and, therefore, a different approach for PA guidelines, research, and promotion. To this aim, we centered the discussion in two topics: 1) PA: from a restricted view to a broader phenomenon; and 2) Recommendations for PA: moving beyond minutes and dose-response. A holistic understanding of PA and its relationship with health is not possible unless it is considered values, meanings, and symbols that impregnate the human behavior linked to the modes of living of a given people. If we do believe that PA is a behavior essential to human life, we must align our actions to our speech. However, current guidelines, as well as in most policies and programs of PA is largely portrayed as a way to attain longer life expectancy and less diseases, which runs against our consolidated understanding of PA as part of our everyday life. New guidelines could focus on how, when, why, where, and with whom we include PA in our daily lives, based on a day-long approach, instead of how much we should do in order to prevent non-communicable diseases.

"For whom was it effective?" Moderators of the effect of a school-based intervention on potential physical activity determinants among Brazilian students.

Knowledge about the effects of school-based interventions on modifiable physical activity (PA) determinants (e.g., social support), and whether the intervention effect differs according to students' characteristics (e.g., age and gender) are relevant PA promotion topics. This study aims to answer these topics among Brazilian students. This cluster-randomized controlled trial was conducted with 548 students in the intervention group and 537 in the control group (51.5% of boys; aged 11-18years). The four-month intervention included strategies focused on training teachers, opportunities for PA in the school environment, and health education. Potential PA determinants (attitude, self-efficacy, support of friends, parents, and teachers, perceived neighborhood environment and PA facilities in school) and moderators (gender, age, socioeconomic status (SES), and PA level at baseline) were assessed using self-reported instrument. Height and weight were measured to estimate the students' body mass index (BMI) status. Generalized linear models were used. In general, there was a significant and positive intervention effect for attitude, support of friends and teachers for PA, as well as PA facilities in school; effect size was 0.29, 0.24, 0.34, and 0.29, respectively (P<0.05). Age (support of friends, parents and teachers, and PA facilities in school), SES (support of friends and PA facilities in school), and BMI status (support of friends) were moderators of the intervention effect on some outcomes. In conclusion, the intervention improved potential PA determinants, but some changes occurred differently according to students' characteristics. These findings should be considered in PA policies in the school context. TRIAL REGISTRATION: This study is registered at Clinicaltrials.govNCT02439827.

Aerobic Fitness and Moderate to Vigorous Physical Activity in Children and Adolescents Living with HIV.

PURPOSE: To examine aerobic fitness, total moderate to vigorous physical activity (MVPA) and also patterns in terms of MVPA between children and adolescents with human immunodeficiency virus (HIV) and controls, and to determine whether differences, if any, are associated with HIV, sex and highly active antiretroviral therapy (HAART). METHOD: A cross-sectional analysis was carried out with 130 children and adolescents, aged between 8 and 15 years, divided into two groups (HIV group= 65 patients, control group= 65 healthy participants). Total MVPA was measured by accelerometers and 5 and 10-min bouts were estimated. The peak oxygen uptake (peak VO2) was measured by breath-by-breath respiratory exchange in an incremental cycle ergometer test. RESULTS: HIV-positive participants had lower peak VO2 (39.2 ± 6.8 vs. 44.5 ± 9.1 ml.kg-1min-1), lower bouts of MVPA of 5-min (19.7 ± 16.6 vs. 26.6 ± 23.5) and 10-min (3.6 ± 3.9 vs. 5.8 ± 7.2), but similar total MVPA (49.5 ± 28.9 vs. 49.1 ± 30.6 min.day-1). HIV infection in untreated, nonprotease inhibitors (PI)- based HAART and PI-based HAART patients was associated with lower 8.5 (95%CI= 12.5-4.6), 7.1 (95%CI= 10.6-3.6) and 4.5 (95%CI= 7.0-2.0) ml.kg-1min-1 of peak VO2. CONCLUSION: Children and adolescents with HIV demonstrated lower aerobic fitness compared with the controls and the absence of HAART may increase peak VO2 impairment. Lower bouts of MVPA were also observed in HIV group despite the similar values of total MVPA of controls.

Promoting physical activity for children and adolescents in low- and middle-income countries: An umbrella systematic review: A review on promoting physical activity in LMIC.

OBJECTIVE: It is unknown how much previous reviews on promoting physical activity (PA) for children and adolescents (aged 6-18years) take into account studies from low- and middle-income countries (LMIC, based on the World Bank definition) and the level of evidence of the effect of PA interventions in this population. This study aims to answer such questions using an umbrella systematic review approach. METHODS: We searched for peer-reviewed systematic reviews and original studies in eight electronic databases, screening of reference lists and expert contacts. Information in systematic reviews on PA interventions for children and adolescents from LMIC was discussed. Original studies on PA interventions (randomized-controlled trials [RCT], cluster-RCT and non-RCT) with children and adolescents from LMIC were eligible. We assessed the methodological quality in all studies, and the evidence level of effect on PA in intervention studies. RESULTS: Fifty systematic reviews (nine meta-analyses) and 25 original studies (20 different interventions) met eligibility criteria. Only 3.1% of mentioned studies in previous reviews were from LMIC. Strong and LMIC-specific evidence was found that school-based, multicomponent, and short-term (up to six months) interventions, focused on adolescents primarily (aged 13-18years), can promote PA in children and adolescents from LMIC. Other intervention characteristics had inconclusive evidence due to the low number of studies, low methodological quality, and/or small sample size. CONCLUSION: A minimal part of PA interventions mentioned in previous reviews are from LMIC. Our LMIC-specific analyses showed priorities of implementation and practical implication that can be used in public policies for PA promotion in LMIC.

Moderating effect of gross family income on the association between demographic indicators and active commuting to work in Brazilian adults.

OBJECTIVE: To investigate the moderating effect of gross family income on the association between demographic indicators and active commuting to work in Brazilian adults. METHODS: Secondary analysis of the survey "Lifestyle and leisure habits of industry workers" (n=46,981), conducted in 24 Brazilian states (2006-2008). Self-reported information was collected with a previously tested questionnaire. Crude and adjusted logistic regression models were applied to analyze the association between sociodemographic variables (sex, age, marital status, number of children, education, country area and company size) and active commuting to work in different strata of gross family income. To test the moderating effect, an interaction analysis was applied. RESULTS: The proportion of active commuters among low-, medium- and high-income workers was 40.7% (95%CI:40.0%;41.5%), 27.0% (95%CI:26.3;27.6%) and 11.1%, (95%CI:10.5%;11.7%), respectively. The moderating effect of gross family income was confirmed. Men were more likely (OR:1.22 95%CI:1.12;1.32) to commute actively than women among low-income individuals. Active commuting was less likely among older workers in low-(OR30-39:0.90 95%CI: 0.83;0.98; OR≥40: 0.76 95%CI: 0.68;0.85) and medium-income strata (OR30-39:0.87 95%CI:0.80;0.95; OR≥40:0.84 95%CI:0.76;0.93) and among married individuals in high-income strata (OR:0.72 95%IC:0.61;0.84). Adults with lower education (ORhigh:10.80 95%CI:8.47;13.77), working in the south (ORhigh:1.93 95%CI:1.53;2.44) and in small companies (ORlow:2.50 95%CI:2.28;2.74) were more likely to commute actively; however, the magnitude of these associations differed at each income strata. CONCLUSION: There was an inverse association between gross family income and active commuting. Gross family income acts as a moderator of the association between demographic indicators and active commuting.

Rationale and methods of a cluster-randomized controlled trial to promote active and healthy lifestyles among Brazilian students: the "Fortaleça sua Saúde" program.

BACKGROUND: Interventions on adolescents' lifestyle are important, but the main mechanisms that explain the changes (mediating variables) on lifestyle are unclear. This paper presents the rationale and methods of an intervention program focused on promoting active and healthy lifestyles (especially physical activity [PA] practice and reducing screen time) among Brazilian students-the Fortaleça sua Saúde program (Portuguese for "strengthen your health"). METHODS/DESIGN: This is a school-based cluster-randomized controlled trial. Three intervention and three control (no intervention) full-time public schools were randomly selected in Fortaleza, northeastern Brazil. Students (n = 1,272) from classes in Grades 7-9 were eligible, and 1,085 (548 in the intervention and 537 in control schools) completed the baseline and follow-up measures. The program duration was approximately four months and took place in 2014. Intervention strategies focused on teacher training, activities on health in the curriculum, active opportunities in the school environment (the availability of equipment for PA), and health education (health materials for students and parents). Data collection was undertaken before and immediately after the intervention. The primary variables included the practice of PA (weekly PA volume, PA behavior change stage and preference for PA during leisure-time) and screen time (TV and computer/video games). Potential intrapersonal, interpersonal and environmental mediators of PA and screen time were evaluated by a standardized questionnaire. Other lifestyle components (e.g., eating habits, substance use), psychological (e.g., self-rated health, body satisfaction) and biological (general and abdominal obesity) aspects, as well as academic performance were also evaluated in the total sample. Depressive symptoms, eating disorders, sleep quality, objectively-measured PA, and sedentary time were evaluated in obese students. DISCUSSION: If effective, this program will contribute to the development of public policies for the promotion of active and healthy lifestyles in youth, especially those from low- and middle-income countries. The main intrapersonal, interpersonal and/or environmental mediators of PA and screen time may also be indicated. Finally, we anticipate that the proposed strategies may be adaptable to public schools and may even be extended to the entire school system. TRIAL REGISTRATION: ClinicalTrials.Gov: NCT02439827 . Registration date: May 3, 2015.