The multiple mediation impact of adolescents' physical fitness and cognitive perceptions on their objective measures - The Cogni-Action Project.

OBJECTIVE: To establish whether physical fitness and cognitive self-perceptions act as mediators in the link between global fitness and cognitive performance measured objectively in adolescents. We also compared differences across sex. METHODS: A total of 1296 adolescents (50 % girls) from grades 5 to 8 (ages 10-14) participated in this cross-sectional study. The ALPHA-fitness test battery assessed physical fitness, comprising cardiorespiratory, speed-agility, and muscular fitness components. We used the 1-5-point International Fitness Scale for physical fitness self-perception, and the 1-10 scale for cognitive performance self-perception. Objective cognitive performance was assessed using a neurocognitive battery consisting of eight tasks. Using principal component analysis, these tasks were grouped into three domains: attention, working memory, and problem solving. We examined three serial mediation models adjusted for sex, standardized body mass index, maturation, and school vulnerability index. RESULTS: Physical fitness and cognitive self-perceptions mediated the effects on attention (B = .0027, CI = .0011 to .0047), memory (B = .0025; CI = .0003 to .0055 and B = .0035; CI = .0009 to .0063), and problem-solving (B = -.0137; CI = -.0231 to -.0052 and B = .0072; CI = .0043 to .0106). By sex, boys showed mediation in all domains, while girls only showed mediation in problem-solving. CONCLUSIONS: Adolescents' perceptions play a crucial and positive mediating role in linking objective measures of physical fitness to cognitive performance outcomes, particularly when self-perceptions of physical fitness and cognition are considered together. Therefore, educating families and school/health environments about the importance of adolescent perceptions, while fostering self-awareness and reinforcing their capabilities, is essential.

Results from Chile's 2022 report card on physical activity for children and adolescents.

Purpose: To summarize the results of Chile's 2022 Report Card (RC) on physical activity (PA) for Children and Adolescents. Methods: Chile's 2022 RC included ten core PA indicators common to the Global Matrix 4.0. Evidence from scientific articles, reports, and databases published between 2018 and January 2022 was included for each indicator. The data were collected and analyzed by a national scientific committee, which assigned letter grades (A to F) using a consensus based on benchmarks defined and revised by the Active Healthy Kids Global Alliance. Results: The committee assigned the following grades: Overall PA, D-; Organized Sports and Physical Activity Participation, C-; Active Play, Incomplete; Active Transportation, D; Sedentary Behavior, D-; Physical Fitness, Incomplete; Family and Peers, D; School, C; Community and Environment, D+; Government, A-. Conclusions: Chile's 2022 RC, like its previous versions, shows persistently low grades for most indicators. Overall PA remained nearly unchanged, while Community and Environment scored lower. Slight improvements were seen in Organized Sports, Family and Peers, and School Environment. While Chile has endeavored to increase children's activity levels, policies require implementation through a systemic, coherent framework to promote sustainable changes and reach a larger portion of children and youth.

Substantial parallel mediation contribution by cognitive domains in the relationship between adolescents' physical fitness and academic achievements: the Cogni-Action Project.

Objective: To determine how cognitive domains mediate the link between fitness components, their global score (GFS), and adolescents' academic achievement (ACA) across various school subjects. Methods: In this study, 1,296 adolescents aged 10-14 participated. GFS was computed by three fitness components (strength, muscular, and cardiorespiratory fitness) through the ALPHA-fitness test battery. ACA was determined by five school subjects (Language, English, Mathematics, Science, and History) and two academic scores (a) "Academic Average" (five subjects) and (b) "Academic-PISA" (Language, Mathematics, and Science). A principal component analysis was performed to establish four factors (working memory [WM], cognitive flexibility [CF], inhibitory control [IC], and fluid reasoning [FR]). A parallel mediation approach was implemented with 5,000 bootstrapped samples controlled for sex, maturity, central obesity, having breakfast before cognitive tasks, schools, and school vulnerability. Total, direct, indirect effects, and mediation percentages were estimated. Results: Overall, the finding showed a full parallel mediation effect for Language (92.5%) and English (53.9%), while a partial mediation for Mathematics (43.0%), Science (43.8%), History (45.9%), "Academic Average" (50.6%), and "Academic-PISA" (51.5%). In particular, WM, IC, and FR mediated all school subjects except mathematics, where IC was not significant. CF has not mediated any relationship between GF and academic performance. Conclusion: This study underscores the pivotal role of cognitive domains, specifically WM, IC, and FR, in mediating the link between physical fitness and academic performance in adolescents. These insights have relevant implications for educational and public health policies.

Associations of pattern-recognition-measured daily activities with sarcopenia and sarcopenic obesity in old age: The IMPACT65+ study.

BACKGROUND: Physical activity has shown beneficial effects for a good state of muscles in aging, but the specific activities of daily living that could be protective remains unclear. This study aimed to analyse the associations of different pattern-recognition-measured daily activities with sarcopenia and sarcopenic obesity in a sample of older adults. METHODS: 200 community-dwelling older adults wore the Intelligent Device for Energy Expenditure and Activity for two consecutive days. Twelve major daily activities recorded were merged in to three common intensity categories: sedentary behaviour (SB), light physical activity (LPA) and moderate-to-vigorous physical activity (MVPA). For physical performance measurements included, hand grip dynamometer and chair-stand tests were used. Skeletal muscle mass and fat mass were estimated by bioelectrical impedance analysis. Associations of daily activities with the study variables were examined using linear regression models. RESULTS: There were no significant associations between total time spent in SB, LPA, or MVPA and sarcopenia. Sarcopenic obesity showed a negative association with total time spent in MVPA [ß (95%CI): -0.29 (-0.41, -0.17)]. Walk at a brisk pace was significatively associated with lower limb physical performance, muscle mass and fat mass % [ß (95%CI): 1.15 (0.40, 1.91); 1.45 (0.68, 2.22) and -2.63 (-4.12, -1.14) respectively]. Other MVPA activities were also significatively associated with the same sarcopenic obesity components [ß (95%CI): 4.65 (0.55, 8.75); 8.59 (4.51, 12.67) and -13.98 (-21.96, -5.99) respectively]. CONCLUSION: Time spent in daily activities of moderate-to-vigorous intensity is negatively associated with sarcopenic obesity but not with sarcopenia.

Study protocol and rationale of "the UP project": evaluating the effectiveness of active breaks on health indicators in desk-based workers.

Background: Excessive sedentary time has been negatively associated with several health outcomes, and physical activity alone does not seem to fully counteract these consequences. This panorama emphasizes the essential of sedentary time interruption programs. "The Up Project" seeks to assess the effectiveness of two interventions, one incorporating active breaks led by a professional and the other utilizing a computer application (self-led), of both equivalent duration and intensity. These interventions will be compared with a control group to evaluate their impact on physical activity levels, sedentary time, stress perception, occupational pain, and cardiometabolic risk factors among office workers. Methods: This quasi-experimental study includes 60 desk-based workers from universities and educational institutes in Valparaiso, Chile, assigned to three groups: (a) booster breaks led by professionals, (b) computer prompts that are unled, and (c) a control group. The intervention protocol for both experimental groups will last 12 weeks (only weekdays). The following measurements will be performed at baseline and post-intervention: cardiometabolic risk based on body composition (fat mass, fat-free mass, and bone mass evaluated by DXA), waist circumference, blood pressure, resting heart rate, and handgrip strength. Physical activity and sedentary time will be self-reported and device-based assessed using accelerometry. Questionnaires will be used to determine the perception of stress and occupational pain. Discussion: Governments worldwide are addressing health issues associated with sedentary behavior, particularly concerning individuals highly exposed to it, such as desk-based workers. Despite implementing certain strategies, there remains a noticeable gap in comprehensive research comparing diverse protocols. For instance, studies that contrast the outcomes of interventions led by professionals with those prompted by computers are scarce. This ongoing project is expected to contribute to evidence-based interventions targeting reduced perceived stress levels and enhancing desk-based employees' mental and physical well-being. The implications of these findings could have the capacity to lay the groundwork for future public health initiatives and government-funded programs.

Self-Reported Moderate-to-Vigorous Physical Activity: Its Association with Health-Related Quality of Life in a Large Cohort of People with Chronic Diseases.

The aim of this study was to investigate the dose-response relationship between physical activity and health-related quality of life (HRQoL) in a large population-based sample of people with chronic disease. We analysed the data of 29,271 adults (15,315 women) who were diagnosed with chronic diseases and participated in the Welsh Health Survey (Wales, UK; data collection 2011-2015). Participants were classified, based on their weekly minutes of moderate-to-vigorous physical activity (MVPA), into four groups as follows: inactive (no MVPA), insufficiently active (<150 min/week), sufficiently active (≥150-<300), and very active (≥300). The main outcome was HRQoL measured via the Short-Form 36 Health Survey (SF-36). This study found a curvilinear association between MVPA and HRQoL and a dose-response relationship for the perception of general health and vitality domains. Compared to inactive participants, those who were very active had higher HRQoL scores (coefficient = 12.54; 95% confidence interval [CI] 11.39-13.70), followed by sufficiently active (coefficient = 11.70; 95% CI 10.91-12.49) and insufficiently active (coefficient = 9.83; 95% CI 9.15-10.51) participants. The fully adjusted regression model showed curvilinear associations between MVPA and the domains of SF-36. Future research should find ways to motivate people with chronic diseases to engage in physical activity. The evidence to support regular exercise in individuals with chronic diseases in all age groups is strong and compelling, and patients should be encouraged to regularly devote more time to physical activity in order to improve their health and well-being.

All-cause mortality attributable to sitting time and physical inactivity in chilean adults.

BACKGROUND: Evidence on all-cause mortality attributable to joint sitting time and physical inactivity is lacking. In this study, we estimated the proportion and number of deaths attributable to sitting time and physical inactivity in Chilean adults. METHODS: A sample of 5834 adults aged 20-96 years from a 2016-2017 Chilean National Health Survey was included to describe the prevalence of 16 joint categories of sitting time and physical activity. Relative risks for the joint association of sitting time and physical inactivity were obtained from a meta-analysis of individual participant data. We retrieved the number of deaths in adults ≥ 20 years in 2019 from the Chilean Ministry of Health. RESULTS: Participants with high sitting time (> 8 h/day) and low physical activity (< 2.5 MET-hour/week) were more likely to be women, 20-64 years, non-indigenous ethnicity, lived in the urban areas, had middle education level and monthly household income, and had public health insurance. Reducing sitting time and increasing physical activity to a theoretical minimum risk exposure level could prevent up to 11,470 deaths or 10.4% of all deaths. Increasing physical activity to >35.5 MET-hour/week and maintaining sitting time could prevent approximately 10,477 deaths or 9.5% of all deaths. Reducing sitting time to < 4 h/day and maintaining physical activity would not reduce the number of deaths (-3.4% or 38 deaths). CONCLUSION: Reducing sitting time may be ancillary for preventing mortality. Therefore, increasing physical activity should be the primary focus of interventions and policies in Chile.

A comparative study between traditional and sports school uniforms on cardiorespiratory and muscular fitness and waist-height-to-ratio in adolescents.

Background: Improving health of children and adolescents is crucial for their overall development. Therefore, it is essential to explore factors that may influence their health at both the public health and school system levels. Objective: This study compares physical fitness components and waist-height-to-ratio (WHtR) in adolescents according to school uniforms, namely the traditional uniform (i.e., shirt and school necktie in boys and skirt and blouse in girls) and the sports uniform (i.e., polo shirts or t-shirts and sport or short trousers). Additionally, it seeks to investigate potential differences in these measures based on sex and school type (i.e., public, subsidized, and private). Methods: This cross-sectional study used data from the Chilean national learning outcome assessment system (SIMCE)-2014 and involved 8,030 adolescents. Cardiorespiratory fitness (CRF) and muscular fitness (MF) were measured. WHtR was assessed as a health cardiovascular indicator. Mixed models and ANCOVA were performed to compare uniform types, adjusting for multiple covariates. value of p and effect size (ES) was used to establish significant results. Results: Overall, sports uniforms (SU) were linked to higher CRF (p < 0.001) than the traditional uniform (TU). Boys from private schools wearing SU presented higher CRF (p = 0.016; ES = 0.37), and a positive trend was observed for MF (p = 0.645; ES = 0.21). In subsidized, a trend was found in CRF (p = 0.005; ES = 0.16). Girls wearing SU from private schools showed a positive trend in CRF (p = 0.167; ES = 0.28). Trends in WHtR were found in both sexes from private (p = 0.555; ES = 0.24; p = 0.444; ES = 0.25, respectively). Conclusion: Wearing SU seems a promissory alternative to promote healthy physical fitness and body composition at the educational level. However, the relationship between higher physical activity and CRF, MF, and lower WHtR due to SU must be verified. Finally, when deciding to implement this measure, special attention must be paid to boys from public schools and girls from all types of schools.

Alarming low physical activity levels in Chilean adults with disabilities during COVID-19 pandemic: a representative national survey analysis.

Background: People with disabilities usually face barriers to regularly engaging in physical activities. Estimating physical activity patterns are necessary to elaborate policies and strategies to facilitate active lifestyles, considering the particular access difficulties experienced by this population. Purpose: This study aimed (i) to describe the prevalence of physical activity levels and (ii) to examine the associations of physical activity levels with socio-demographic variables and type of disability in the 2020 Chilean National Physical Activity and Sports Habits in Populations with Disabilities (CNPASHPwD) survey during the coronavirus disease 19 (COVID-19) pandemic. Methods: Cross-sectional data from 3,150 adults (18-99 years old), 59.8% female, were analyzed from November to December 2020. Self-reported age, gender, type of disability (i.e., physical, visual, hearing, intellectual, or mixed), socio-economic status, area and zone of residence, and physical activity levels (0 min/week, < 150 min/week, ≥ 150 min/week) were obtained. Results: 11.9% of the participants were classified as active (≥ 150 min/week), and 62.6% declared no involvement in physical activity. A larger proportion of females (61.7%) did not meet the current guidelines (≥ 150 min/week of physical activity) in comparison with males (p < 0.001). Participants with visual and hearing disabilities were more likely to be active than those with other types of disabilities. Those living in the central and southern regions of Chile were more likely to be physically active than those from the northern region. Also, older participants, women, and those from lower socio-economic statuses were less likely to meet the physical activity guidelines. Conclusion: Alarmingly, nine out of ten participants were categorized as physically inactive, particularly women, older adults, and those with a low socioeconomic status. If the pandemic context moderated, the considerable prevalence of reduced physical activity levels deserves future exploration. Health promotion initiatives should consider these aspects, emphasizing inclusive environments and increasing opportunities to favor healthy behaviors, countering the COVID-19 effects.

Physical Activity and Sitting Time Patterns and Sociodemographic Correlates Among 155,790 South American Adults.

BACKGROUND: To estimate the prevalence of different physical activity (PA) domains and sitting time (ST), and to analyze the association with sociodemographic indicators. METHODS: Data from the most recent nationally representative survey from each of the South American countries, comprising 155,790 adults (18-64 y), were used. Data on leisure-time, transport, and occupational PA (all 3 domains as nonzero), total PA (≥150 min/wk), and ST (≥8 h/d) were assessed by specific questionnaires in each survey. Gender, age group (18-34, 35-49, and 50-64 y), and education (quintiles) were used as sociodemographic factors. Random effect meta-analysis of the association between sociodemographic factors and PA and ST were conducted. RESULTS: The prevalence of PA guidelines compliance and elevated ST in South America was 70.3% and 14.1%, respectively. Women were less likely to achieve the recommended levels of total and domain-based PA. Participants in the highest quintile of education were more likely for elevated ST (2.80, 2.08-3.77), lower occupational PA (0.65, 0.44-0.95), but higher leisure-time PA (3.13, 2.31-4.27), in comparison with lowest quintile. Older adults were less likely to participate in total and leisure-time PA. CONCLUSION: Our findings highlight the urge to tackle the inequalities in PA practice in South America, especially gender and education inequalities, for leisure-time PA.

Sex differences in change of direction deficit and asymmetries in footballers with cerebral palsy.

The aims of this study were (1) to describe and examine differences in change of direction (COD) performance and the magnitude of asymmetries in para-footballers with cerebral palsy (CP) and controls and (2) to evaluate the association between COD outcomes and linear sprint performance. Twenty-eight international para-footballers with CP and thirty-nine non-impaired football players (control group) participated in this study. All participants completed a 10-m sprint and two attempts of the 505 COD test with the dominant and non-dominant leg. The COD deficit was calculated using the difference between the 505 test and the 10-m sprint time, while the asymmetry index was determined by comparing each leg's completion time and COD deficit. Players across groups showed interlimb asymmetries between the dominant and non-dominant legs in COD outcomes and deficit (p < 0.05, dg = -0.40 to -1.46), although these asymmetries imbalance were not significantly different between the sexes with and without impairment. Males with CP exhibited a faster directional COD speed and a shorter COD deficit than their female counterparts (p < 0.01, dg = -1.68 to -2.53). Similarly, the control group had faster scores than the CP groups of the same sex (p < 0.05, dg = 0.53 to 3.78). Lastly, the female CP group and male control groups showed a significant association between sprint and the COD deficit in the dominant leg (p < 0.05, r = -0.58 to 0.65). Therefore, the use of directional dominance, the COD deficit, and asymmetry outcomes could be helpful for classification purposes to assess the impact of the impairment on sport-specific activity testing according to sex.

Effectiveness of exergames programme to modify body composition and health-related physical fitness in adolescents with down syndrome after COVID-19 quarantine.

AIMS: to determine the effect of a 20-week exergame program on different indicators of body composition and components of health-related physical fitness in adolescents with Down syndrome. Methods and Procedures Outcomes: 49 adolescents (19 female and 30 males; average age, 14.19 ± 2.06 years) with Down syndrome were recruited and randomized to two groups (control group vs. intervention group). Adolescents allocated in the control group carried out a physical activity program three times a week for 20 weeks meanwhile adolescents allocated in the exercise group performed an exergame program three times a week for 20 weeks. RESULTS: The exercise group had significant improvements in all health-related physical fitness variables and there is an improvement in some body composition variables (p < 0.05). CONCLUSIONS AND IMPLICATIONS: 20 week exergame program consisting of 3 sessions of 60 minutes is able to improve levels of body composition and health-related physical fitness in adolescents with Down syndrome.Highlights Research in body composition and health-related physical fitness of people with Down syndrome has revealed that an exergame programme increases levels of health-related physical fitness in adolescents with Down syndromeAn exergame programme can improve differences in markers of body composition between the control group and the intervention groupThe intervention group that performed the exergame programme showed increases in health-related physical fitness levels after 20 weeks of intervention.The control group that performed a based on developing motor behaviour programme did not show differences in body composition or health-related physical fitness after 20 weeks of intervention.

Exchanging screen for non-screen sitting time or physical activity might attenuate depression and anxiety: A cross-sectional isotemporal analysis during early pandemics in South America.

OBJECTIVES: To examine the theoretical substitutions of screen exposure, non-screen sitting time, moderate and vigorous physical activity with depressive and anxiety symptoms in South American adults during the COVID-19 pandemic. DESIGN: A cross-sectional study during the first months of the COVID-19 pandemic with data from 1981 adults from Chile, Argentina, and Brazil. METHODS: Depressive and anxiety symptoms were assessed using the Beck Depression and Anxiety Inventories. Participants also reported physical activity, sitting time, screen exposure, sociodemographic, and tobacco use data. Isotemporal substitution models were created using multivariable linear regression methods. RESULTS: Vigorous physical activity, moderate physical activity, and screen exposure were independently associated with depression and anxiety symptoms. In adjusted isotemporal substitution models, replacing 10 min/day of either screen exposure or non-screen sitting time with any intensity of physical activity was associated with lower levels of depressive symptoms. Improvements in anxiety symptoms were found when reallocating either screen exposure or non-screen sitting time to moderate physical activity. Furthermore, replacing 10 min/day of screen exposure with non-screen sitting time was beneficially associated with anxiety (B = -0.033; 95 % CI = -0.059, -0.006) and depression (B = -0.026; 95 % CI = -0.050, -0.002). CONCLUSIONS: Replacement of screen exposure with any intensity of physical activity or non-screen sitting time could improve mental health symptoms. Strategies aiming to reduce depressive and anxiety symptoms highlight physical activity promotion. However, future interventions should explore specific sedentary behaviors as some will relate positively while others negatively.

Alcohol use in self-isolation during the COVID-19 pandemic: a cross-sectional survey in Brazil.

OBJECTIVES: To assess alcohol use and perceived change in alcohol consumption (before and during the pandemic) in Brazilians during the COVID-19 pandemic, their correlates, and their associations with depressive, anxiety and co-occurring depressive and anxiety symptoms (D&A). METHODS: This is a cross-sectional study comprising 992 individuals in self-isolation. A self-report questionnaire was used to assess whether participants were drinking during self-isolation and whether they changed their drinking behavior (drinking less, more, or no change) from before to during the pandemic. D&A symptoms were assessed using the Beck Depression and Anxiety Inventories (BDI and BAI). RESULTS: A total of 68.5% of participants reported alcohol consumption during the pandemic, and 22.7% of these reported increased alcohol use. Smoking was positively associated with alcohol consumption during the pandemic. Alcohol consumption was associated with anxiety (OR = 1.40, 95%CI 1.06-1.85, p < 0.01) and D&A (OR = 1.38, 95%CI 1.02-1.87, p = 0.033) symptoms. CONCLUSIONS: Drinking during self-isolation was prevalent and was associated with risk factors for alcohol use disorders. The long-term effects of high drinking rates and increased consumption should be proactively monitored and assessed.

Physical activity and diabetes mortality in people with type 2 diabetes: a prospective cohort study of 0.5 million US people.

AIM: To examine the association between physical activity and the cause of death with the greatest risk related to type 2 diabetes mellitus (T2DM) in a large population-based cohort representative of the general US adult population. METHODS: A total of 41,726 adults suffering from T2DM (age 62 ± 14 years) and 459,660 adults without diabetes (age 46 ± 18 years) who participated in the National Health Interview Survey from 1997 to 2014 were included in this prospective cohort study. Self-reported moderate-to-vigorous physical activity (MVPA) was categorized into inactive, insufficiently active, active and very active. Mortality data was obtained from the National Death Index. Cox regression models adjusted for potential confounders were performed to estimate hazard ratio (HR) and 95% confidence interval (CI). RESULTS: Diabetes mortality cause showed the highest relative risk of death among adults with T2DM compared to adults without diabetes (HR 5.72 [3.15;10.39]). There was a non-linear inverse dose-response association between MVPA and diabetes mortality among adults with T2DM, up to a plateau in risk reduction at approximately 500 min/week. Any level of activity was inversely associated with a significantly lower risk of diabetes mortality compared with being inactive (insufficiently active HR 0.71[0.54;0.97], active HR 0.68 [0.49;0.95], very active HR 0.44 [0.32;0.60]). Compared to adults without diabetes, the risk of diabetes mortality decreased from HR 7.38 [4.00;13.58] for inactive people with T2DM to HR 3.34 [1.76;6.32] for very active people with T2DM. CONCLUSIONS: Higher levels of MVPA were associated with lower risk of diabetes mortality among adults with T2DM.

Alcohol use in self-isolation during the COVID-19 pandemic: a cross-sectional survey in Brazil

Abstract Objectives To assess alcohol use and perceived change in alcohol consumption (before and during the pandemic) in Brazilians during the COVID-19 pandemic, their correlates, and their associations with depressive, anxiety and co-occurring depressive and anxiety symptoms (D&A). Methods This is a cross-sectional study comprising 992 individuals in self-isolation. A self-report questionnaire was used to assess whether participants were drinking during self-isolation and whether they changed their drinking behavior (drinking less, more, or no change) from before to during the pandemic. D&A symptoms were assessed using the Beck Depression and Anxiety Inventories (BDI and BAI). Results A total of 68.5% of participants reported alcohol consumption during the pandemic, and 22.7% of these reported increased alcohol use. Smoking was positively associated with alcohol consumption during the pandemic. Alcohol consumption was associated with anxiety (OR = 1.40, 95%CI 1.06-1.85, p < 0.01) and D&A (OR = 1.38, 95%CI 1.02-1.87, p = 0.033) symptoms. Conclusions Drinking during self-isolation was prevalent and was associated with risk factors for alcohol use disorders. The long-term effects of high drinking rates and increased consumption should be proactively monitored and assessed.

Physical activity and daily steps cut offs points for overweight/obesity prevention among eight Latin American countries.

This study aims to establish cut-off points for the number of minutes of physical activity intensity and the number of daily steps that identify overweight/obesity in adolescents, adults, and older adults. This study examined data from 2737 participants. Physical activity intensity and the number of daily steps were assessed using GT3X+ ActiGraph model accelerometers. Body mass index, waist-to-height ratio, and waist-to-hip ratio were used as indicators of overweight/obesity. The cut-off points for moderate-to-vigorous physical activity for the prevention of overweight/obesity according to body mass index in women ranged from 15.1 to 30.2 min/day; in men, the values were from 15.4 to 33.8 min/day. The lowest cut-off point for daily steps was established in the adolescent group for women and men (7304 and 5162). The highest value in women was 11,412 (51-65 years) and 13,234 in men (18-30 years). Results from measurements different from BMI, show average cut-off points for moderate-to-vigorous physical activity and daily steps of 29.1/8348 and 43.5/10,456 according to waist-to-height ratio; and results of 29.3/11,900 and 44.3/11,056 according to the waist-to-hip ratio; in women and men respectively. A more specific recommendation of physical activity and daily steps adjusted by sex and age range is suggested to prevent overweight/obesity.

Walking and cycling, as active transportation, and obesity factors in adolescents from eight countries.

BACKGROUND: Evidence has shown that active transportation decreases obesity rates, but considering walking or cycling as separate modes could provide additional information on the health benefits in adolescents. This study aimed to examine the associations between walking and cycling as form active transportation and obesity indicators in Latin American adolescents. METHODS: Population-based study with 671 adolescents (mean age: 15.9 [standard deviation: 0.8] years) from eight countries participating in the Latin American Study of Nutrition and Health/Estudio Latino Americano Nutrition y Salud (ELANS). Walking and cycling for active transportation were measured using the International Physical Activity Questionnaire long version. Body mass index, waist circumference, neck circumference, and relative fat mass were used as obesity indicators. Associations were estimated using logistic regression models for the pooled data adjusted for country, sex, age, socio-economic levels, race/ethnicity, leisure-time physical activity and energy intake. RESULTS: Mean time spent walking and cycling was 22.6 (SD: 33.1) and 5.1 (SD: 24.1) min/day, respectively. The median values were 12.8 (IQR: 4.2; 25.7) and 0 (IQR: 0; 6.2) for walking and cycling. Participants reporting ≥ 10 min/week of walking or cycling for active transportation were 84.2% and 15.5%, respectively. Costa Rica (94.3% and 28.6%) showed the highest prevalence for walking and cycling, respectively, while Venezuela (68.3% and 2.4%) showed the lowest prevalence. There was no significant association between walking for active transportation and any obesity indicator. In the overall sample, cycling for ≥ 10 min/week was significantly associated with a lower likelihood of overweight/obesity based on BMI (OR: 0.86; 95%CI: 0.88; 0.94) and waist circumference (OR: 0.90; 95%CI: 0.83; 0.97) adjusted for country, sex, age, socio-economic level, race/ethnicity, leisure-time physical activity and energy intake compared to cycling for < 10 min/week. There were no significant associations between cycling for active transportation and neck circumference as well as relative fat mass. CONCLUSIONS: Cycling for active transportation was negatively associated with obesity indicators, especially body mass index and waist circumference. Programs for promoting cycling for active transportation could be a feasible strategy to tackle the high obesity rates in adolescents in Latin America. TRIAL REGISTRATION: ClinicalTrials.Gov NCT02226627. Retrospectively registered on August 27, 2014.

Which one? A comparative study of traditional and sports uniforms on academic achievement, cognitive performance, playtime, bullying, and discrimination in adolescents: The Cogni-Action Project.

Objective: The aim of this study was to compare academic achievement, cognitive performance, playtime, bullying, and discrimination in adolescents according to traditional uniforms (TUs) and sports uniforms (SUs) worn at school, while simultaneously exploring the influence of the school vulnerability index. Methods: A total of 988 Chilean adolescents (52.6% boys) aged 10-14 years participated in this cross-sectional study. Academic achievement was evaluated by the average grade in maths, language, and science grades, while cognitive performance was assessed through eight cognitive tasks. TUs affecting physical activity, playtime, bullying, and discrimination were queried. Mixed model analyses were performed. Results: No differences were observed in academic achievement (TU: 5.4 ± 0.1 vs. SU: 5.5 ± 0.2, p = 0.785) or in cognitive performance (TU: 99.6 ± 0.8 vs. SU: 98.9 ± 1.8, p= 0.754) according to the school uniformtype. Moreover, 64.1 % of participants declared that wearing TU affects their physical activity (traditional uniforms: + 8 min and sports uniforms: + 20 min), and those who believed so spent more time playing than those who answered negatively (14.5 min, p = 0.012). Finally, adolescents wearing SU displayed a lower feeling of bullying and discrimination; this finding depended mainly on the school's vulnerability. Conclusion: It is concluded that wearing TU does not show an educational advantage at an academic and cognitive level that justifies its obligation. In addition, it could be suggested that schools consider adolescents' opinions in adopting a more comfortable uniform, such as the SU. This feasible and low-cost measure would help to increase adolescents' physical activity during the school day, and, contrary to belief, it would not be related to increased feelings of bullying and discrimination.

Time trends and inequalities of physical activity domains and sitting time in South America.

Background: We aimed to investigate time trends and inequalities of different physical activity (PA) domains and sitting time (ST) in adults from South American countries. Methods: We included cross-sectional data of nationally representative surveys on adults (n = 597 843) from nine South American countries (Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Peru, Uruguay, and Venezuela), with data collection time frames ranging from 2005 to 2020. Data on different PA domains (leisure-time, transport, and occupational) and ST were assessed through questionnaires. Trends according to education level (quintiles), gender (m/w), and age group (18-34 years, 35-49 years, 50-64 years) were estimated for the harmonized indicators of nonzero PA in the different domains, ≥150 min/week of total PA and ≥8 hours/d of ST. Results: Chile (2009/2010 = 78.9% vs 2016/2017 = 70.5%), and Peru (2009/2010 = 78.6% vs 2011 = 69.6%) reduced total PA, while Brazil (2013 = 57.3% vs 2019 = 67.0%) and Uruguay (2006 = 69.4% vs 2013 = 79.4%) increased, and Argentina and Venezuela maintained. There was an increasing trend for ST in Argentina, Peru, and Uruguay. Leisure-time PA increased in most countries (6/8 countries). Transport PA was relatively stable, while occupational PA presented mixed findings. Education inequalities increased over time for total and leisure-time PA, while age and gender inequalities were relatively constant. Conclusions: Future South American countries' efforts may be warranted to promote PA and reduce ST in adults, while addressing inequalities when implementing actions.