Physical fitness and its association with cognitive performance in Chilean schoolchildren: The Cogni-Action Project.

This study aimed to establish the association and differences in a diversity of cognitive domains according to cardiorespiratory fitness (CRF), muscular fitness (MF), and speed-agility fitness (S-AF) level in a large sample of Chilean schoolchildren. 1171 Chilean schoolchildren aged 10-14 years participated. CRF, MF, and S-AF were assessed through the ALPHA-fitness test battery. Cognition was evaluated through the NeuroCognitive Performance Test, which involved eight tests related to four main domains: cognitive flexibility (CF), working memory (WM), inhibitory control (IC), and intelligence (IN). Both global (multivariate) and individual (univariate) analyses were performed to determine the differences in cognitive functioning according to low-, middle-, and high-fitness level. The global analyses showed a significant main effect for CRF, F(16,940)  = 3.08, p ≤ .001 and MF groups, F(16,953)  = 2.30, p = .002, but not for S-AF, F(16,948)  = 1.37, p = .105. CRF shows a significant main effect in seven of eight tests, involving CF, WM, IC, and IN domains, whereas MF shows a significant main effect in five of eight tests without association with IN. SA-F shows a significant main effect only with IC. Statistical differences were found between the low- and middle/high-fitness groups but not between the middle- and high-fitness groups. At a global level, both CRF and MF seem to be associated with a higher cognitive profile in scholars; however, at an individual level, all fitness components show a favorable relationship to some cognitive domine. Then, future cognitive developing strategies should consider all fitness components, prioritizing those low-fitness schoolchildren.

Active commuting to school among 36,781 Spanish children and adolescents: A temporal trend study.

This study examines trends in the rates of active commuting to school (ACS) in Spanish children (n = 18 343; 8.93 ± 1.68) and adolescents (n = 18 438; 14.11 ± 1.58) aged 6-18 years from 2010 to 2017. Given the study period included the economic crisis in Spain (2008-2013), the second aim of this study was to compare ACS rates during and after the economic crisis. Data were obtained from 28 studies conducted across Spain. The overall trends in ACS were evaluated using multilevel logistic regression analysis. Among Spanish children and adolescents, the rates of ACS to school ranged around 60% between 2010 and 2017. The rates of ACS in Spanish youth did not change significantly during the 2010-2017 period, except a sporadic increase in the rate of ACS in adolescents in 2012-2013. No significant association between the ACS and the economic crisis time period in youth was found. As conclusion, the ACS remains stable in Spain during the last decade, which is a promising result regarding the evidenced decreasing trend in many countries. Further educational and policy strategies are important to continue promoting this behavior in children and adolescents in the long term.

[Effects of physical exercise on aerobic fitness and cognition in older women with type 2 diabetes mellitus]. / Efectos de un programa de entrenamiento de marcha sobre las capacidad aeróbica y la función cognitiva en mujeres diabéticas de edad avanzada.

BACKGROUND: Among older people, physical exercise improves cognitive function, aerobic fitness, and thus functional independence. AIM: To determine the effects of a walking training program on aerobic fitness and cognitive function in older women with type 2 diabetes mellitus. MATERIAL AND METHODS: An experimental study was carried out in 76 women with type 2 diabetes mellitus aged between 64 and 78 years. Thirty-eight women in the exercise group (EG) participated in a controlled walking program 3 times a week for 48 sessions (60min /day) and 38 women in the control group (CG) were not trained. Weight, height, body mass index (BMI), estimated maximal oxygen uptake (VO2max), and cognitive function using the Minimental test were evaluated at baseline and the end of the intervention. RESULTS: The Minimental test improved significantly in the exercise group and did not change in the control group. Estimated VO-2max improved in women aged between 69 and 78 years. The distance walked in 6 minutes increased in all women of the experimental group. No changes in these parameters were observed in the control group. CONCLUSIONS: A structured walking program improved cognitive function, estimated aerobic capacity, and walking distance in these diabetic women.

Is the perceived neighborhood built environment associated with domain-specific physical activity in Latin American adults? An eight-country observational study.

BACKGROUND: Characteristics of the neighborhood built environment are associated with physical activity (PA). However, few studies with representative samples have examined environmental correlates of domain-specific PA in Latin America. We examined the associations of the perceived neighborhood built environment with domain-specific PA in a large sample of adults from eight Latin American countries. METHODS: This study examined data from 8185 adults (aged 18-65 years) from eight Latin American countries. The Neighbourhood Environment Walkability Survey - Abbreviated (NEWS-A) scale was used to assess perceptions of land use mix-diversity, land use mix-access, street connectivity, walking/cycling facilities, aesthetics, safety from traffic, and safety from crime. Perceived proximity from home to public open spaces (metropolitan parks, playgrounds, public squares) and to shopping centers was also measured. Transport-related and leisure-time PA were assessed using the long form of the International Physical Activity Questionnaire. Both logistic and linear regression models were estimated on pooled data. RESULTS: Perceptions of higher land use mix-access (OR: 1.40; 95% CI: 1.22,1.61), the existence of many alternative routes in the neighbourhood (1.12; 1.04,1.20), slow speed of traffic (1.19; 1.03,1.35) and few drivers exceeding the speed limits (1.09; 1.03,1.15) were associated with greater odds of reporting at least 10 min/week of transport-related PA. Perceptions of higher levels of land use mix-diversity, better aesthetics and greater safety from crime, the presence of crosswalks and pedestrian signals, and greater proximity of shopping centers were associated with more min/week of transport-related PA. Perceptions of higher land use mix-diversity (1.12; 1.05,1.20), higher land use mix-access (1.27; 1.13,1.43), more walking/cycling facilities (1.18; 1.09,1.28), and better aesthetics (1.10; 1.02,1.18) were associated with greater odds of engaging in at least 10 min/week of leisure-time PA versus none. Perceptions of higher land use mix-diversity were associated with more min/week of leisure PA. CONCLUSIONS: Different perceived neighborhood built environment characteristics were associated with domain-specific PA among adults from Latin America countries. Interventions designed to modify perceptions of the neighbourhood built environment might influence initiation or maintenance of domain-specific PA. TRIAL REGISTRATION: ClinicalTrials. Gov NCT02226627 . Retrospectively registered on August 27, 2014.

The Gut Barrier, Intestinal Microbiota, and Liver Disease: Molecular Mechanisms and Strategies to Manage.

Liver disease encompasses pathologies as non-alcoholic fatty liver disease, non-alcoholic steatohepatitis, alcohol liver disease, hepatocellular carcinoma, viral hepatitis, and autoimmune hepatitis. Nowadays, underlying mechanisms associating gut permeability and liver disease development are not well understood, although evidence points to the involvement of intestinal microbiota and their metabolites. Animal studies have shown alterations in Toll-like receptor signaling related to the leaky gut syndrome by the action of bacterial lipopolysaccharide. In humans, modifications of the intestinal microbiota in intestinal permeability have also been related to liver disease. Some of these changes were observed in bacterial species belonging Roseburia, Streptococcus, and Rothia. Currently, numerous strategies to treat liver disease are being assessed. This review summarizes and discusses studies addressed to determine mechanisms associated with the microbiota able to alter the intestinal barrier complementing the progress and advancement of liver disease, as well as the main strategies under development to manage these pathologies. We highlight those approaches that have shown improvement in intestinal microbiota and barrier function, namely lifestyle changes (diet and physical activity) and probiotics intervention. Nevertheless, knowledge about how such modifications are beneficial is still limited and specific mechanisms involved are not clear. Thus, further in-vitro, animal, and human studies are needed.

[Association of physical inactivity with low levels of education]. / Nivel educativo y su asociación con niveles de actividad física en Chile.

BACKGROUND: A higher educational level is associated with healthier lifestyles. AIM: To assess the association between the level of compliance with physical activity recommendations and years of formal education in Chilean adults. MATERIAL AND METHODS: Analysis include 6,174 participants from the National Health Survey 2016-2017. Physical activity levels were assessed through the Global Physical Questionnaire (GPAQ v2). Physical inactivity was defined as < 600 MET/minute/week. RESULTS: Among subjects without education, 44% and 27% of women and men respectively, were physically inactive. Among women and men with the highest number of years of education (> 16) the figures for physical inactivity were 27% and 15% respectively. The odds for not meeting the physical activity recommendations was 2.3 [95% confidence intervals (CI): 1.57; 3.38] and 3.9 [95% CI: 2.27; 6.95] in women and men without any formal education respectively, as compared with those who reported 12 years of education. Women and men who reported a high level of education ≥ (16 years) did not show significant differences compared to the reference group. CONCLUSIONS: People with low levels of education are were likely to be physically inactive.

[Comparison between self-reported and device measured physical activity according to nutritional status]. / Comparación de los niveles de actividad física medidos con cuestionario de autorreporte (IPAQ) con medición de acelerometría según estado nutricional.

BACKGROUND: It is unknown if nutritional status could influence the accuracy of self-reported physical activity (PA) levels. AIM: To compare PA measured using the international physical activity questionnaire (IPAQ) and by accelerometry (ActiGraph) according to nutritional status in Chilean adults. MATERIAL AND METHODS: This is an observational cross-sectional study that used information from the GENADIO project carried out in Chile between 2009-2011. The sample consisted of 322 people. PA levels and sitting time were determined through the IPAQ self-report questionnaire and ActiGraph accelerometers (GTM1). The nutritional status was determined according to body mass index (BMI). RESULTS: Compared with the measurement made with accelerometry, the IPAQ self-report questionnaire underestimated the levels of light PA, total PA and sedentary time in -171.5, -54.8 and -40.6 min / day, respectively. However, IPAQ overestimated the levels of moderate PA and vigorous PA in 91.0 and 47.3 min/day respectively, compared with accelerometry. Compared with normal weight, obese subjects reported higher levels of moderate PA (105.5 and 48.9 min/day, respectively) and vigorous PA (54.1 and 38.3 min/day respectively). Total PA had a greater delta of underestimation between IPAQ and accelerometer measurements in normal weight than in obese subjects (-122.1 vs -16.5 min/day, respectively). CONCLUSIONS: The measurement of PA by means of a self-report questionnaire was discrepant with its objective measurement with an accelerometer. The discrepancy is even higher in obese people.

Changes in compliance with school-based physical activity recommendations in Spanish youth: The UP&DOWN longitudinal study.

The study aimed (a) to examine changes in physical activity (PA) during the whole day, school hours, recess, and physical education classes (PEC) during a 2-year period in primary and secondary students; (b) to identify changes in the proportion of compliance with specific PA recommendations for these periods; and (c) to examine whether PA levels at baseline are associated with PA levels 2 years later. Eight hundred and fourteen (51.8% boys) children and 658 (50.1% boys) adolescents from 41 Spanish schools participated in the study. Hip-worn accelerometers were used to assess PA during different time periods. Light PA (LPA) declined during the whole day, school hours, recess (all P < 0.001, except child girls for recess), and PEC (all, P < 0.05) in children and adolescents. Moderate-to-vigorous PA (MVPA) during the whole day and recess declined in child boys (P < 0.01 and P < 0.001, respectively) and adolescent boys (P < 0.001 and P < 0.05, respectively). MVPA during PEC declined in adolescent boys (P < 0.001) and adolescent girls (all P < 0.05). The proportion of compliance with the specific PA recommendations for these periods declined (P < 0.05), except for PEC in adolescent girls. PA during the whole day at baseline was moderately associated with PA during the whole day years later (ICCs = 0.210-0.544, with one exception), but this association was lower for the school-based PA. In conclusion, time spent in MVPA and LPA during the whole day and recess declined over time in child and adolescent boys and during PEC in adolescents. These findings highlight the need to promote PA interventions in these settings.

Study protocol and rationale of the "Cogni-action project" a cross-sectional and randomized controlled trial about physical activity, brain health, cognition, and educational achievement in schoolchildren.

BACKGROUND: Education and health are crucial topics for public policies as both largely determine the future wellbeing of the society. Currently, several studies recognize that physical activity (PA) benefits brain health in children. However, most of these studies have not been carried out in developing countries or lack the transference into the education field. The Cogni-Action Project is divided into two stages, a cross-sectional study and a crossover-randomized trial. The aim of the first part is to establish the associations of PA, sedentarism, and physical fitness with brain structure and function, cognitive performance and academic achievement in Chilean schoolchildren (10-13 years-old). The aim of the second part is to determinate the acute effects of three PA protocols on neuroelectric indices during a working memory and a reading task. METHODS: PA and sedentarism will be self-reported and objectively-assessed with accelerometers in a representative subsample, whilst physical fitness will be evaluated through the ALPHA fitness test battery. Brain structure and function will be assessed by magnetic resonance imaging (MRI) in a randomized subsample. Cognitive performance will be assessed through the NeuroCognitive Performance Test, and academic achievement by school grades. In the second part 32 adolescents (12-13 year-old) will be cross-over randomized to these condition (i) "Moderate-Intensity Continuous Training" (MICT), (ii) "Cooperative High-Intensity Interval Training" (C-HIIT), and (iii) Sedentary condition. Neuroelectric indices will be measures by electroencephalogram (EEG) and eye-tracking, working memory by n-back task and reading comprehension by a reading task. DISCUSSION: The main strength of this project is that, to our knowledge, this is the first study analysing the potential association of PA, sedentarism, and physical fitness on brain structure and function, cognitive performance, and academic achievement in a developing country, which presents an important sociocultural gap. For this purpose, this project will use advanced technologies in neuroimaging (MRI), electrophysiology (EEG), and eye-tracking, as well as objective and quality measurements of several physical and cognitive health outcomes. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03894241 Date of register: March 28, 2019. Retrospectively Registered.

Association of leisure time and occupational physical activity with obesity and cardiovascular risk factors in Chile.

The aim of this study was to investigate the association between physical activity (PA), both occupational (OPA) and during leisure time (LTPA), with obesity and cardiovascular risk factors in Chilean adults. 5,157 participants from the Chilean National Health Survey 2009-2010 were included in this study. OPA and LTPA levels were assessed using the Global Physical Activity Questionnaire. The association between both PA with obesity and cardiovascular risk factors was determined using logistic regression. Our findings showed a significant trend between higher LTPA and lower odds for obesity (OR 0.64 [95% CI: 0.53; 0.76], central obesity 0.52 [0.44; 0.61]) and other cardiovascular risk factors including diabetes (OR: 0.72 [0.55; 0.94]), hypertension (OR: 0.59 [0.50; 0.71]) and metabolic syndrome (OR: 0.62 [0.50; 0.78]). In contrast, OPA was only associated with lower odds of diabetes (OR: 0.79 [0.65; 0.98]) and hypertension (0.85 [0.74; 0.98]). In conclusion, LTPA was associated with a lower risk of all major cardiovascular risk factors, whereas OPA was only associated with a lower risk of diabetes and hypertension.

[Lifestyles of Chilean housewives. Analysis of the 2009-2010 Chilean Health Survey]. / Caracterización de los estilos de vida en dueñas de casa chilenas. Análisis de la Encuesta Nacional de Salud 2009-2010.

BACKGROUND: Housewives represent a important proportion of the Chilean population. However, there is limited evidence about their lifestyles. AIM: To characterize lifestyles and determine the level of compliance with healthy lifestyles guidelines of housewives in Chile. MATERIAL AND METHODS: Housewives from the 2009-2010 National Health Survey were included. The variables studied included levels of physical activity (PA), sedentary behavior, diet, hours of sleep and smoking. Compliance with healthy lifestyle behaviors was evaluated through logistic regression, granting a value of 1 for compliance and 0 for non-compliance. A healthy lifestyle was defined as meeting at least four healthy behaviors. RESULTS: Housewives aged > 55 years had a higher BMI and waist circumference compared to those aged < 40 years. Housewives were also more likely to report moderate alcohol consumption and were more likely to meet a healthier lifestyle score (Odds ratio = 1.52 [95% confidence intervals: 1.09 to 2.11], p = 0.013). No significant age trends were observed for other lifestyle behaviors. CONCLUSIONS: Housewives had high levels of central obesity, excess body weight and high levels of salt intake but low alcohol intake. Their healthy lifestyles behaviors increased along with increasing age.

Active Commuting to University and its Association with Sociodemographic Factors and Physical Activity Levels in Chilean Students.

Background and Objectives: Active commuting to and from university (ACU) could be a strategy to increase physical activity levels (PA) and promote health in young university students. We aimed to a) examine the patterns of commuting to university in Chilean students; b) the association between the mode of commuting to and from university and socio-demographic factors and PA-levels. Materials and Methods: A total of 496 university students (21.6 ± 2.4 years old) from two universities from Valparaíso (central coast of Chile) participated in this study. Personal data, home address, socio-economic status, PA, and the usual mode of commuting to and from the university were self-reported by a questionnaire. The commute distances were objectively measured using Google-Maps-software. Associations were examined using binary logistic regressions. Results: The main mode of commuting was by bus (to university: 55.2% vs. from university: 59.3%; p < 0.001). The least used mode was cycling (1.4% to and from university). Students living >5-km from university were less active commuters than those living in closer distances: (2-5 km, odds ratio (OR): 4.424, 95% and 95% confidence intervals (CI): 2.443-8.011, p < 0.001; 2 km, OR: 143.052, 95% CI: 55.154-371.030, p < 0.001). Students with low PA-levels were less active commuters than those with medium (OR: 1.446; 95% CI: 0.864-2.421; p = 0.160) or higher levels (OR: 1.880; 95% CI: 1.880-1.094; p = 0.022). Students who lived between 2 and 5 km, presented a significant association to be active commuters when they showed medium PA-levels (OR: 5.244, 95% CI: 1.358-20.246; p = 0.016). Conclusions: Chilean university students from Valparaíso are mainly passive commuters using public transport as the main mode of commuting to and from university; longer distances from home to the university are associated with low PA levels. ACU in distances between 2-5 km (mainly walking) could contribute to having medium PA-levels in Chilean university students. Thus, promoting the ACU walking to and from the university in such distances could be an effective strategy to increase the overall PA levels in Chilean university students.

Normative Reference of Standing Long Jump for Colombian Schoolchildren Aged 9-17.9 Years: The FUPRECOL Study.

Ramírez-Vélez, R, Martínez, M, Correa-Bautista, JE, Lobelo, F, Izquierdo, M, Rodríguez-Rodríguez, F, and Cristi-Montero, C. Normative reference of standing long jump for Colombian schoolchildren aged 9-17.9 years: The FUPRECOL study. J Strength Cond Res 31(8): 2083-2090, 2017-The purpose of this study was to generate normative values for the standing long jump (SLJ) test in 9- to 17.9-year olds and to investigate sex and age-group differences. The sample comprised 8,034 healthy Colombian schoolchildren [boys n = 3,488 and girls n = 4,546; mean (SD) age 12.8 (±2.3) years old]. Each participant performed two SLJ. Centile smoothed curves, percentile, and tables for the third, 10th, 25th, 50th, 75th, 90th, and 97th percentiles were calculated using Cole's Lambda-Mu-Sigma method. The 2-way analysis of variance tests and Cohen's d showed that the maximum SLJ (centimeter) was higher in boys than in girls across age groups (p < 0.01), reaching the peak at 13 years. Posthoc analyses within the sexes showed yearly increases in SLJ in all ages. In boys, the 50th percentile SLJ score ranged from 109 to 165 cm. In girls, the 50th percentile jump ranged from 96 to 120 cm. For girls, jump scores increased yearly from age 9 to 12.9 years before reaching a plateau at an age between 13 and 15.9. Our results provide, for the first time, sex- and age-specific SLJ reference values for Colombian schoolchildren aged 9-17.9 years. The normative values presented in this study provide the basis for the determination of the proposed age- and sex-specific standards for the FUPRECOL (Association for Muscular Strength with Early Manifestation of Cardiovascular Disease Risk Factors Among Colombian Children and Adolescents) Study-Physical fitness battery for children and adolescents.

High muscular fitness has a powerful protective cardiometabolic effect in adults: influence of weight status.

BACKGROUND: Low levels of muscular fitness (MF) are recognized as an important marker of nutritional status and a predictor of metabolic complications, cardiovascular disease and death, however, the relationship between MF, body mass index (BMI) and the subsequent cardiometabolic protective effects has been less studied among Latin American populations. This study identified an association between MF and the cardiometabolic risk score index (CMRSI) and the lipid-metabolic cardiovascular risk index (LMCRI) in a wide sample of university students grouped according to their BMI. METHODS: Six thousand ninety five healthy males (29.6 ± 11.7 year-old) participated in the study. Absolute strength was measured using a T.K.K. analogue dynamometer (handgrip), and the participant's strength was then calculated relative to their body mass (MF/BM). The LMCRI was derived from the levels of triglycerides, low-density lipoprotein cholesterol (LDL-c), high-density lipoprotein cholesterol (HDL-c), and glucose levels in a blood sample. The CMRSI was calculated by summing the standardized residuals (z-score) for waist circumference, total cholesterol, LDL-c, triglycerides, HDL-c, and median blood pressure. Subjects were divided into six subgroups according to BMI (normal vs. overweight/obese) and MF/BM tertiles (unfit, average, fit). RESULTS: The group of participants with low and moderate levels of MF/BM showed higher CMRSI values independent of BMI (P < 0.001). The group with normal BMI and high MF/BM had the highest levels of cardiometabolic protection. All overweight/obese BMI groups had significantly higher LMCRI values independent of the level of MF/BM (P < 0.001). CONCLUSIONS: Participants with high MF/BM showed reduced cardiometabolic risk, which increased significantly when they were within normal parameters.

Variations of body composition, physical activity and caloric intake in schoolchildren during national holidays.

UNLABELLED: Scientific literature has described that a significant body weight increase in schoolchildren occurs during some holiday periods (summer, winter, and thanksgiving holidays), harming their health. In this regard, it is thought that this phenomenon is mainly due to changes in eating habits and the variation in levels of physical activity; however, this approach has not yet been explored during national holidays (NAH) in Chile. PURPOSE: To determine any changes in body composition, physical activity and caloric intake during NAH. METHODS: A total of 46 schoolchildren (24 boys, age 10.5 ± 0.5; BMI 21.7 ± 4.7) participated. Measurements were performed 2 days before and after the NAH (9 days). Weight was measured and fat percentage was established using the Slaughter formula. Levels of physical activity were measured with accelerometers, validating 3 weekdays and 1 weekend; caloric intake was established through a 24-h recall. RESULTS: Weight, percentage of fat and caloric intake increased significantly (250 g, 2.2 % and 733.3 kcal, respectively; p < 0.05); however, none of the variables of physical activity showed significant changes. CONCLUSION: The change in caloric intake seems to be the main cause of weight and fat gain during the NAH.

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.