Effectiveness of an Ecological Model-Based Active Transport Education Program on Physical and Mental Health in High School Students (MOV-ES Project): Study Protocol for a Randomized Controlled Trial.

The United Nations, through its 2030 Agenda and Sustainable Development Goals, advocates for the establishment of conducive environments for physical activity, following the ecological model. In line with this initiative, active transportation emerges as an accessible, cost-effective, and sustainable approach to augmenting daily physical activity levels. This study protocol endeavors to assess the impact of an active transportation education program rooted in the ecological model on the physical and mental well-being of high school students. Drawing upon scientific insights, we hypothesize that a 16-week active transportation intervention will lead to a 3% reduction in average body fat percentage and a noteworthy enhancement in executive function (including inhibition, cognitive flexibility, and working memory), physical fitness (comprising cardiorespiratory fitness and muscle strength), and mental health (encompassing mood disorders and cognitive functioning). If this intervention proves effective, it could offer a viable solution for the school community, especially in reducing congestion within the school environment. The study protocol aims to evaluate the impact of an active transportation educational program based on the ecological model on the physical and mental well-being of high school students. Three high schools located in the urban area of Talca, Chile, will be randomly selected (one public, one privately subsidized, and one private non-subsidized). Each high school will be randomly assigned an experimental group (n = 30) and a control group (n = 30; without intervention). The experimental groups will receive an active transportation educational intervention during their physical education classes for four months (60 to 90 min sessions, once a week), while the control group will receive no intervention. The primary outcome will provide information on body composition and executive function. Secondary outcomes will include objective physical activity level, physical fitness, mental well-being, academic achievement, health-related quality of life, perception of environmental urban features, physical activity barriers, and adherence to active transportation. It is expected that the results of the MOV-ES Project will transcend the physical health of schoolchildren and will have an impact on the school community, especially by decongesting the school environment.

Association between Gross Motor Competence and Physical Fitness in Chilean Children Aged 4 to 6 Years.

The preschool period is considered critical for the development of motor competence, but as far as we know, no studies have investigated the association between motor competence and physical fitness in Chilean children. The aim of this study was to analyse the association between gross motor competence and physical fitness, controlling for possible confounding factors. A cross-sectional study was conducted with a sample of 144 preschool children (56.25% girls) with an average age of 5.3 years (4 to 6 years) from the Araucanía region, Chile. Motor competence was measured using the Children's Movement Assessment Battery, 2nd Edition (MABC-2). Regarding physical fitness, the components of cardiorespiratory fitness, lower body muscle strength and speed/agility were evaluated using the Battery to Assess FITness in PREschool (PREFIT). Partial correlation models and analysis of variance (ANCOVA) were used to assess differences in physical fitness between motor competence categories, controlling for age and body mass index. The mean fitness scores for cardiorespiratory fitness, lower body muscle strength and speed/agility components were significantly higher in children with higher gross motor competence. In terms of effect size, large values were found for the lower body strength component in model 1 for boys and in model 2 for the total samples of girls and boys. The results of this study suggest that good levels of gross motor competence are associated with better physical fitness levels.

The Effects of a Physical Activity Intervention on Adiposity, Physical Fitness and Motor Competence: A School-Based, Non-Randomized Controlled Trial.

Evidence suggests that early physical activity interventions are a means of preventing childhood obesity and are more effective when delivered in a school setting and based on the ecological model. Therefore, the present study aims to determine the effect of a multicomponent intervention based on the ecological model on adiposity, physical fitness and motor competence in children aged 4 to 5 years. METHODS: This study is a non-randomized controlled trial involving 173 children from Chile. The intervention was based on an ecological model and consisted of a physical activity program with three simultaneous parts, affecting intra- and interpersonal dimensions. The adiposity index, body mass index and waist circumference were measured. For physical fitness, muscle strength in the lower part, speed/agility and cardiorespiratory fitness were measured. Motor competence was assessed using catching, aiming and dynamic and static balance tests. RESULTS: After the intervention, there was no reduction in adiposity indices; in the intervention group, body mass index increased significantly with a high effect size. The intervention group showed significant differences in physical fitness in the components of muscle strength in the lower part (p = 0.000) and speed/agility (p = 0.002). For motor competence, the intervention group showed significant improvements in most components. CONCLUSIONS: The multicomponent intervention did not reduce adiposity indices; however, it caused significant improvements in the physical fitness and motor competence components, so it seems prudent to continue implementing it, given the benefits that adequate levels of motor competence and physical fitness bring to children's health, both in the short and long term.

Intensity of a Physical Exercise Programme Executed through Immersive Virtual Reality.

Evidence suggests that moderate to vigorous physical activity (MVPA) is necessary for health benefits. Immersive virtual reality is a technology that uses images, sounds, and tactile sensations from a simulated world to encourage healthy behaviours and physical activity. The aims of this research are (1) to determine the duration and intensity of physical activity performed through immersive virtual reality; (2) to determine differences in physical activity intensity according to gender. METHODS: A nonprobabilistic convenience sample composed of 39 university students of physical education pedagogy, who performed, through immersive virtual reality, a physical activity programme composed of three levels that progressively increased in complexity. Physical activity intensity was measured using accelerometers. RESULTS: Of the three levels, the most complex was not the one that produced the most minutes of MVPA. The three levels added up to 08:53 min of MVPA. No significant differences were found when comparing them by sex. CONCLUSIONS: The results of this study suggest that an exercise programme delivered through immersive virtual reality generates MVPA levels, with no major differences between sexes. Further research is needed to confirm the contribution of immersive virtual reality to physical activity.

Physical Activity in Immersive Virtual Reality: A Scoping Review.

Physical activity has benefits for health, but many adolescents are inactive. However, video games such as Immersive Virtual Reality (IVR) have grown in popularity as a leisure activity among young people, allowing them to manipulate objects in virtual environments increasing the practice of physical activity. The evidence indicates that the interest in physical activity through IVR is greater than in traditional methods, and different experiences have been reported. However, few studies indicate the sample evaluated, the effects found, or the IVR instruments used. Due to this, is the aim of this study is to identify the publications referring to IVR and physical activity, characterize them, and present the obtained main findings. For this, the guidelines described in the PRISMA-ScR for scoping reviews were applied. After the use of the inclusion and exclusion criteria, eight articles were included. Results show evidence regarding physiological outcomes, perceptual variables, interest and enjoyment, and psychological effects regarding physical activity through IVR. Additionally, the use of different devices and their prescriptions are explored. It is concluded that there is interest from the scientific community for the practice of physical activity through IVR, as well as for its application for the maintenance of active habits. This is important as it positions IVR as a method that can be a more experiential and effective way to develop and maintain a healthy lifestyle.

The Association between Sedentary Behavior, Physical Activity, and Physical Fitness with Body Mass Index and Sleep Time in Chilean Girls and Boys: A Cross-Sectional Study.

BACKGROUND: In recent decades, the school population has undergone behavioral changes that have affected their health and adult life. The current educational scenario presents high levels of sedentary behavior, physical inactivity, low physical fitness, high levels of obesity, and non-compliance with sleep recommendations. In Chile, the scientific evidence on associations between these behaviors is incipient. OBJECTIVE: To analyze the association between sedentary behavior, physical activity, and physical fitness with BMI and minutes of sleep in Chilean children aged 10 to 11 years. METHODS: A non-probabilistic convenience sample of 222 schoolchildren aged 10 to 11 years. The variables measured were body composition (BMI), cardiorespiratory fitness (20 m shuttle run test), lower and upper muscular strength (long jump test and handgrip dynamometry), speed (4 × 10 m running), and flexibility (sit and reach test). Physical activity and sleep were measured by accelerometers. RESULTS: Of the participants, 60.4% and 90.6% did not comply with sleep and physical activity recommendations, respectively. Physical fitness was higher in boys in all components. The results of the linear regression show that in girls, moderate-vigorous-intensity physical activity, lower- and upper-body muscular strength, and cardiorespiratory endurance were associated with BMI and sleep. In boys, light-intensity physical activity and upper-body muscular strength were associated with both variables. CONCLUSIONS: Physical activity intensity, strength, and cardiorespiratory fitness were associated with BMI and sleep; however, physical activity intensity and associated physical fitness components differed by gender.

Effects of physical activity interventions on anthropometric indicators and health indices in Chilean children and adolescents: A protocol for systematic review and/or meta-analysis.

INTRODUCTION: Physical activity interventions have been a proven effective means of preventing or treating overweight and obesity in children and adolescents. The results of these interventions in many cases are based on the determination of the effect they produce on anthropometric evaluations, which allow the calculation of health indices. However, the effects of physical activity interventions on anthropometric assessments in Chilean children and adolescents have not been systematized. The objective of this study is to provide a detailed protocol for a systematic review with meta-analysis that synthesizes the available evidence on the effect of physical activity interventions on anthropometric indicators and health indices in Chilean children and adolescents and identifies the field-based methods and health indices most used for body composition estimation. METHODS: This protocol was performed according to the PRISMA declaration. MEDLINE (PubMed), Web of Science, Scopus, and Scielo databases will be systematically searched. Eligible studies will include randomized controlled trials (RCTs), non-RCTs and pre-post studies. CONCLUSION: This systematic review and meta-analysis protocol is designed to provide up-to-date evidence that could significantly assist public health policy makers and implementers of physical activity interventions through evidence-based guidance and recommendations.

Consumption of ultra-processed food and its association with obesity in Chilean university students: A multi-center studyUltra-processed food and obesity in Chilean university students.

OBJECTIVE: To explore the associations between the consumption of three categories of ultra-processed food (sugary beverages, sweet, and salty snacks) and body mass index (BMI) among Chilean university students. METHODS: We conducted a multi-center, descriptive study among 2,039 students from 6 Chilean universities. Food consumption was surveyed using a validate food survey. That height and body weight were objectively measured to calculate BMI for determining weight status, and also, tobacco use and physical activity were measured. RESULTS: An intake equal to or higher than 1 serving of sugary beverage a day was associated with greater odds of obesity in university students (OR:1.32 [95% CI: 1.00, 1.74]), 2 servings/day (OR: 1.30 [95% CI: 1.04, 1.50]), and 3 servings/day (OR: 1.39 [95% CI: 1.05, 1.80]). Neither consumption of sweet nor salty snacks (≥1 servings/day) related to differential odds of obesity: (OR: 0.83 [95% CI: 0.42, 1.64]) and (OR: 1.79 [95% CI: 0.93, 3.41]), respectively. CONCLUSION: In a sample of Chilean university students, consumption of sugary beverages, and not consumption of sweet or salty snacks, was associated with obesity.

Tendencia de consejerías en actividad física y enfermedades cardiometabólicas en el Maule, Chile: estudio previo a pandemia por COVID-19 entre 2012 y 2019 / Trend in Physical Activity Counseling and Cardiometabolic Diseases in Maule, Chile: COVID-19 Pre-Pandemic Study between 2012 and 2019

BACKGROUND: Physical activity (PA) practice reduces the adverse effects of COVID-19. PA counseling promotes healthy lifestyles and prevents cardiometabolic diseases. AIM: To assess the trend in cases of PA counseling and the cardiometabolic disease between 2012 and 2019 (before COVID-19) in a southern Chilean region. MATERIAL AND METHODS: Records of Maule Region Health Service for 731.163 men, and 829.097 women aged < 10 to ≥ 65 years were analyzed. The average annual percentage change (AAPC) during the study period and the annual percentage change (APC) during intermediate periods, were calculated. RESULTS: There was a significant decrease in PA counseling in women in the study period (AAPC: −13.6%). In the 2012-2017 period a significant decrease in counseling for total, men and women were observed (APC: −18.1, −16.5 and −19.1%, respectively). Obesity increased significantly in total, men and women in the 2012-2019 period (AAPC: 10.1, 8.5 and 10.7%, respectively). The same trend was observed for hypertension (AAPC: 8.1, 8.5 and 7.6% respectively) and elevated blood glucose (AAPC: 10, 11.5 and 9.6%, respectively). CONCLUSIONS: In the study period PA counseling decreased along with an increase in obesity, hypertension and high blood glucose. Increasing PA counseling is a mainstay in the prevention of cardiometabolic diseases and probably to prevent contagion and complement the treatment of COVID-19.

Mediterranean Diet Interventions for Depressive Symptoms in Adults with Depressive Disorders: A Protocol for a Systematic Review and Meta-Analysis.

The associations between Mediterranean diet (MD) adherence and depression levels have been synthesized from observational studies. However, a systematic review with meta-analysis including randomized controlled trials (RCTs) on this relationship in adults with depressive disorders remains lacking. This protocol was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analysis for Protocols statement. MEDLINE (PubMed), Cochrane CENTRAL, PsycINFO, Scopus, and Web of Science databases will be systematically searched to identify studies published from database inception up to 30 September 2022. The inclusion criteria will comprise RCTs reporting pre-post changes in depression status (symptoms or remission) after a MD intervention compared to a control condition in adults over 18 years with depressive disorders. Pooled effect sizes and 95% confidence intervals will be calculated using the DerSimonian random-effects model. This study protocol determines the methodological approach for the systematic review and meta-analysis that will summarize the available evidence on the efficacy of MD interventions on depressive symptoms in adults with depressive disorders. The findings from this review may have implications for public mental health programs. The results will be disseminated through peer-reviewed publication, conference presentation, and infographics. No ethical approval will be required since only published data will be used. PROSPERO registration number: CRD42022341895.

Effectiveness of a physical activity intervention on the overweight and obesity of Chilean schoolchildren.

INTRODUCTION: Physical fitness is considered a measure that integrates most of the functions of the human organism that are involved in physical activity. Motor competence is important due to its observed implications in the physical, mental and social development of children and adolescents. These assessments require the existence of updated reference values that allow the categorization of individuals and groups according to levels of physical fitness and motor competence. This paper describes the study protocol to Effectiveness of a Physical Activity Intervention on the Overweight and Obesity of Chilean Schoolchildren, and in this way determine, through the calculation of a representative sample, reference values for physical fitness and motor competence in children aged 4 to 6 years in the region of La Araucanía, Chile. METHODS: children in pre-basic education in transition grades I and II (4 and 5 years old), and those in the first year of basic education (6 years old) will be invited to participate. The sample will be probabilistic. The measures of a randomized controlled trial (registered in ClinicalTrial.gov NCT04194580) will be used. CONCLUSION: the lack of reference values for physical condition and motor competence for children between 6 and 4 years of age in the Araucanía region highlights the need to establish values, which will contribute to improving the health of children of the age group to be worked on.

Association between Sleep Quality and Physical Activity in Physical Education Students in Chile in the Pandemic Context: A Cross-Sectional Study.

Background: Due to the health restrictions put in place to face the pandemic, a decrease in the levels of physical activity and an alteration in the quality of sleep have been observed. One group susceptible to these changes is represented by students of physical education pedagogy, who, under normal conditions, present high levels of physical activity. However, the correlation between these variables has not been studied in the context of a pandemic lockdown. Objective: The aim of this study was to determine the prevalence of the quality of sleep and physical activity level as a function of gender and evaluate the association between quality of sleep and physical activity level in physical education pedagogy students during the COVID-19 pandemic considering sociodemographic and health characteristics. Methods: This was a cross-sectional study. An online questionnaire was applied to 280 Chilean university students of physical education pedagogy. The survey considered sociodemographic information, healthy habits, and self-reported health and included the International Physical Activity Questionnaire (IPAQ) for physical activity levels and the Pittsburgh Sleep Quality Index (PSQI) for sleep quality. Results: The prevalence of good sleep quality was 20.4%. Furthermore, 52.9% of students had a high level of physical activity. Regression analysis between PSQI global score and age-adjusted physical activity levels indicated that being male and presenting a high level of physical activity favored a better PSQI global score. Conclusions: The prevalence of good sleep quality was low in general and significantly lower in women. Being male and having a high level of physical activity during quarantine benefits good sleep quality, regardless of age.

Anthropometric Indicators of the Cardiometabolic Risk, Muscle Strength, and Functional Capacity of Schoolchildren with Intellectual Disabilities during Lockdown in Chile.

Lockdown due to the COVID-19 pandemic has negatively impacted the social, psychological, and physical well-being of the world population. In the case of people with intellectual disabilities, the impact of lockdown on their physical condition and functionality is not completely clear. This study aimed to determine the effects of COVID-19 lockdown on the anthropometric indicators of cardiometabolic risk, muscle strength, and functionality on schoolchildren with intellectual disabilities. The sample was composed of 132 students of both sexes (n = 74 pre-lockdown; n = 58 lockdown) belonging to two special education centers from the Metropolitan Region of Santiago, Chile. Our results showed significant reductions (p ≤ 0.05) in absolute and relative handgrip strength, as well as in functionality, when comparing pre-lockdown and lockdown measurements, with a greater loss in girls than boys. The design and implementation of physical exercise programs centered on strength training are necessary for the physical and functional reconditioning of this population. These programs need to be implemented in special education centers considering the general well-being, quality of life and work needs of people with intellectual disabilities.

Associations between Physical Activity Level and Health Services Use in Spanish Adults.

One of the main concerns of governments and organisations worldwide is the cost and burden of health services, with sedentary lifestyles being a significant impacting factor, and physical activity is one of the potential solutions. Therefore, this study aims to analyse the possible associations between the physical activity level, hospitalisation prevalence, and the use and number of visits to emergency services in the Spanish population, examining potential differences between sex and age groups. This is a cross-sectional study based on data from the Spanish National Health Survey 2017 (ENSE 2017), the last one before the COVID-19 pandemic, with 17,199 participants. A descriptive analysis was performed using median and interquartile range (continuous variables) and absolute and relative frequencies (ordinal variables). Intergroup differences were analysed with non-parametric tests: chi-square and z-test for independent proportions (categorical variables), and Kruskal−Wallis and Mann−Whitney U (continuous variables). Spearman's rho was used to study correlations between variables. A multiple binary regression analysis was performed to predict hospitalisations. Hospitalisations and emergency services use showed a dependence relation with the physical activity level (p < 0.001): those who performed moderate and/or vigorous physical activity used those services less than sedentary individuals and those whose only activity was walking. Thus, associations could be drawn between the hospitalisation prevalence, the use and number of visits to emergency departments, and the physical activity level in the Spanish population aged 18−69 years in the pre-pandemic period.

Estimated Oxygen Consumption with the Abbreviated Method and Its Association with Vaccination and PCR Tests for COVID-19 from Socio-Demographic, Anthropometric, Lifestyle, and Morbidity Outcomes in Chilean Adults.

COVID-19 causes cardiovascular and lung problems that can be aggravated by confinement, but the practice of physical activity (PA) could lessen these effects. The objective of this study was to evaluate the association of maximum oxygen consumption (V˙O2max) with vaccination and PCR tests in apparently healthy Chilean adults. An observational and cross-sectional study was performed, in which 557 people from south-central Chile participated, who answered an online questionnaire on the control of COVID-19, demographic data, lifestyles, and diagnosis of non-communicable diseases. V˙O2max was estimated with an abbreviated method. With respect to the unvaccinated, those who received the first (OR:0.52 [CI:0.29;0.95], p = 0.019) and second vaccine (OR:0.33 [CI:0.18;0.59], p = 0.0001) were less likely to have an increased V˙O2max. The first vaccine was inversely associated with V˙O2max (mL/kg/min) (ß:−1.68 [CI:−3.06; −0.3], p = 0.017), adjusted for BMI (ß:−1.37 [CI:−2.71; −0.03], p = 0.044) and by demographic variables (ß:−1.82 [CI:−3.18; −0.46], p = 0.009); similarly occur for the second vaccine (ß: between −2.54 and −3.44, p < 0.001) on models with and without adjustment. Having taken a PCR test was not significantly associated with V˙O2max (mL/kg/min). It is concluded that vaccination significantly decreased V˙O2max, although it did not indicate cause and effect. There is little evidence of this interaction, although the results suggest an association, since V˙ O2max could prevent and attenuate the contagion symptoms and effects.

A Cross-Sectional Study on Self-Perceived Health and Physical Activity Level in the Spanish Population.

One-third of the Spanish population over 15 years of age did not achieve a reasonable amount of physical activity (PA) before the COVID-19 pandemic. We aim to analyse the associations between the PA level (PAL) and self-perceived health (SPH) in the Spanish population aged 15−69 years during the pre-pandemic period. A cross-sectional study was conducted using the Spanish National Health Survey 2017 (ENSE 2017) data, with 17,777 participants. We carried out a descriptive analysis, analysed intergroup differences with non-parametric statistical tests, and calculated the Odds Ratio (OR) and Relative Risk (RR) of having a negative SPH according to PAL. In addition, correlations between PAL and SPH were studied, finding associations between them (p < 0.001). Thus, performing moderate and intense PA was related to better SPH than just walking or inactive. Weak and moderate correlations were found between PAL and SPH (p < 0.001). We also found high ORs and RRs of negative SPH as PAL decreased. Moderate and intense PA were related to positive SPH, while the risk of negative perception in inactive people was higher.

[Trend in Physical Activity Counseling and Cardiometabolic Diseases in Maule, Chile: COVID-19 Pre-Pandemic Study between 2012 and 2019]. / Tendencia de consejerías en actividad física y enfermedades cardiometabólicas en el Maule, Chile: estudio previo a pandemia por COVID-19 entre 2012 y 2019.

BACKGROUND: Physical activity (PA) practice reduces the adverse effects of COVID-19. PA counseling promotes healthy lifestyles and prevents cardiometabolic diseases. AIM: To assess the trend in cases of PA counseling and the cardiometabolic disease between 2012 and 2019 (before COVID-19) in a southern Chilean region. MATERIAL AND METHODS: Records of Maule Region Health Service for 731.163 men, and 829.097 women aged < 10 to ≥ 65 years were analyzed. The average annual percentage change (AAPC) during the study period and the annual percentage change (APC) during intermediate periods, were calculated. RESULTS: There was a significant decrease in PA counseling in women in the study period (AAPC: -13.6%). In the 2012-2017 period a significant decrease in counseling for total, men and women were observed (APC: -18.1, -16.5 and -19.1%, respectively). Obesity increased significantly in total, men and women in the 2012-2019 period (AAPC: 10.1, 8.5 and 10.7%, respectively). The same trend was observed for hypertension (AAPC: 8.1, 8.5 and 7.6% respectively) and elevated blood glucose (AAPC: 10, 11.5 and 9.6%, respectively). CONCLUSIONS: In the study period PA counseling decreased along with an increase in obesity, hypertension and high blood glucose. Increasing PA counseling is a mainstay in the prevention of cardiometabolic diseases and probably to prevent contagion and complement the treatment of COVID-19.

Physical fitness of Latin America children and adolescents: a protocol for a systematic review and meta-analysis.

INTRODUCTION: Physical fitness (PF) is an important indicator of health in children and adolescents. Internationally, test batteries have been used to assess overall PF. In Latin America, however, while PF has been widely measured, there is no accepted test battery, making it difficult to monitor and/or compare the PF levels of Latin children. The aim of this study, therefore, is to systematically review and potentially meta-analyse the peer-reviewed literature regarding the assessment of PF in Latin American children and adolescents. METHODS AND ANALYSIS: This systematic review and meta-analysis will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols statement. The systematic literature search will be performed in MEDLINE, Scopus, SciELO, EMBASE, Cochrane Library, Web of Science, SPORTDiscus, LILACS and Latindex (Spanish) to locate articles published up to April 2021. Eligible studies will include both descriptive and analytic study designs. Meta-analyses are planned for sufficiently homogeneous PF outcomes with regard to statistical and methodological characteristics. Narrative syntheses are planned for PF outcomes that are considered to be too heterogeneous. The statistical program STATA V.15 will be used for meta-analyses, with subgroup analyses performed according to the characteristics of included studies. ETHICS AND DISSEMINATION: This systematic review and meta-analysis protocol is designed to provide updated evidence on the PF of Latin American children and adolescents. Findings from this review may be useful for teachers, researchers and other professionals responsible for paediatric fitness and health promotion/surveillance. The results will be disseminated through peer-reviewed scientific publications, conferences, educational talks and infographics. PROSPERO REGISTRATION NUMBER: CRD42020189892.

Changes in anthropometric parameters and physical fitness in older adults after participating in a 16-week physical activity program / Cambios en los parámetros antropométricos y la condición física en adultos mayores luego de participar en un programa de actividad física de 16 semanas

Abstract Introduction: Physical activity is important for achieving healthy aging. Objective: To analyze changes in anthropometric parameters and physical fitness among Chilean older adults after participating in a 16-week physical activity program and to evaluate whether there were differences in relation to their baseline nutritional status or not. Materials and methods: Pre-experimental quantitative study. The study population consisted of 176 older adults (155 women and 21 men) distributed in three groups: normal weight (n = 56), overweight (n=67) and obese (n = 53). The following variables were evaluated: body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHR) and physical fitness. Results: Significant decreases between pre- and post-measurements were found for WC (p<0.001), BMI (p=0.015), and WHR (p<0.001). Improvements were observed in the following tests: chair stand (p<0.001), arm curl (p<0.001), 2-min step (p<0.001), chair sit-&-reach (p=0.018) and back scratch (p=0.014). Regarding BMI, significant changes were observed between normal weight vs. overweight participants (p=0.001) and between normal weight vs. obese participants (p=0.001). Conclusion: Older adult participants that regularly attended the physical activity program were able to reduce their WC, BMI and WHR, and also improved their physical-functional performance on the chair stand, arm curl, 2-min step, chair sit-&-reach and back scratch tests. In addition, anthropometric parameters and physical fitness also improved regardless of their baseline nutritional status.

Resumen Introducción. La actividad física es de gran importancia para lograr un envejecimiento saludable. Objetivos. Estudiar los cambios en los parámetros antropométricos y la condición física de adultos mayores (AM) chilenos después de 16 semanas de participación en un programa de actividad física, y evaluar las diferencias en relación con su estado nutricional inicial. Materiales y métodos. Estudio pre-experimental cuantitativo. Población: 176 AM (155 mujeres y 21 hombres) distribuidos en 3 grupos: normopesos (n = 56), sobrepesos (n=67) y obesos (n = 53). Se evaluaron las siguientes variables: índice de masa corporal (IMC), perímetro de cintura (PC), índice cintura-estatura (ICE) y condición física. Resultados. Se observaron reducciones significativas en PC (p<0.001), IMC (p=0.015) e ICE (p<0.001), y mejoras en las siguientes pruebas: sentarse y levantarse de una silla (p<0.001), flexiones del codo (p<0.001), dos minutos de marcha (p<0.001), flexión del tronco en silla (p=0.018) y juntar las manos tras la espalda (p=0.014). Se encontraron diferencias significativas respecto al IMC entre participantes normopesos y sobrepesos (p=0.001), y entre normopesos y obesos (p=0.001). Conclusión. Los AM que participaron regularmente en el programa de actividad física lograron reducir su PC, IMC e ICE y mejorar su rendimiento físico-funcional en las pruebas de sentarse y levantarse de una silla, flexiones de codo, dos minutos de marcha, y flexibilidad del tren inferior y superior. Además, sus parámetros antropométricos y su condición física mejoraron independientemente de su estado nutricional inicial.

The Effects of Physical Activity and Diet Interventions on Body Mass Index in Latin American Children and Adolescents: A Systematic Review and Meta-Analysis.

The objective of this systematic review and meta-analysis is to compare the effect of physical activity only with that of physical activity plus diet interventions on body mass index (BMI) in Latin American children and adolescents. We searched the Medline, Embase, Scopus, Web of Science, and Scielo databases from their inception until March 2020, including studies examining the effect of physical activity or physical activity plus diet interventions on BMI in children and adolescents and based on data from intervention studies. The DerSimonian and Laird method was used to compute a pooled standardized mean difference for BMI in terms of effect size (ES) and respective 95% confidence intervals (CIs). Eighteen studies were included. Analyses were performed based on intervention (four studies were included for physical activity only and four studies were included for physical activity plus diet). In the analysis of physical activity only versus control, there was no effect on BMI (ES = 0.00; 95% CI -0.17-0.17, I2 = 0.0%; p = 0.443). In the analysis of physical activity plus diet versus control, there was a decrease in BMI in favour of the intervention group (ES = -0.28; 95% CI -0.42--0.14, I2 = 74.5%; p = 0.001). When ES was estimated considering only the effect in intervention groups, there was no evidence of a decrease in BMI (ES = -0.17; 95% CI -0.44-0.11, I2 = 84.5%; p < 0.001) for physical activity only (eight studies). However, there was a statistically significant decrease in BMI (ES = -0.30; 95% CI -0.50-0.11, I2 = 95.8%; p < 0.001) for physical activity plus diet (ten studies). Some limitations of this review could compromise our results, but the main limitation that should be stated is the quality of the studies (mainly medium/moderate), especially as physical activity and diet interventions cannot be blinded, compromising the quality of these studies. In summary, this meta-analysis offers evidence that physical activity plus diet interventions produced a reduction in BMI in Latin American children and adolescents, but physical activity only interventions did not.