Chronic effects of school physical activity on cognitive performance in youngs: a systematic review protocol / Efeitos crônicos da atividade física escolar no desempenho cognitivo de jovens: um protocolo de revisão sistemática

Recent systematic reviews point out the positive acute effects of physical activity on executive func-tions in children and adolescents, but the chronic effects in this age group are still uncertain. This study aims to describe a systematic review with meta-analysis protocol to elucidate the chronic effects of physical activity at school on the executive functions and attention of children and ad-olescents, considering the effect-moderators and examining different interventions in the school environment. A systematic search will be carried out for studies published in the PUBMED, Em-base, Scopus and Cochrane Library databases. Studies that meet the following predefined criteria (PICOS criteria) will be included: 1) studies conducted with healthy children and adolescents (6-18 years-old), 2) studies with physical activity interventions in school, 3) studies conducted with a control group, and 4) studies with cognitive flexibility, working memory, inhibitory control and attention outcomes. Target outcomes will be extracted as pre-and post-test values. Intervention time, frequencies, intensity, volume, session time, and intervention type will be extracted for meta-regres-sion analysis. For methodological quality will be using the tool for the assessment of study quality and reporting in exercise training studies. Pooled effect estimates will be calculated from the scores of changes between baseline and end of interventions. The effect size will be expressed as Cohens' and presented as standardized mean differences and calculations will be performed using random-effects models. Statistical heterogeneity will be evaluated by Cochran's Q statistic and the I² inconsistency test. The meta-analyses will be performed using OpenMeta[Analyst]

Revisões sistemáticas recentes apontam os efeitos agudos positivos da atividade física nas funções executivas em crianças e adolescentes, mas os efeitos crônicos nessa faixa etária ainda são incertos. Este artigo tem como objetivo descrever o protocolo de revisão sistemática e meta-análise que busca elucidar os efeitos crônicos da atividade física no ambiente escolar sobre as funções executivas e atenção de crianças e adolescentes, conside-rando os efeitos-moderadores e examinando diferentes tipos de intervenções no ambiente escolar. Será reali-zada uma busca sistemática de estudos publicados nas bases de dados PUBMED, Embase, Scopus e Cochrane Library. Serão incluídos estudos que atendam aos seguintes critérios pré-definidos (critérios PICOS): 1) estudos realizados com crianças e adolescentes saudáveis (6-18 anos), 2) estudos com intervenções de ativi-dade física na escola, 3) estudos de intervenção, randomizados ou não, realizados com grupo controle e 4) estudos com flexibilidade, memória de trabalho, controle inibitório e resultados de atenção. Os resultados alvo serão extraídos como valores pré e pós-teste. Tempo de intervenção, frequências, intensidade, volume, tempo de sessão e tipo de intervenção serão extraídos para análise de meta-regressão. Para a qualidade metodológica será utilizado o instrumento para avaliação da qualidade do estudo e relato em estudos de treinamento físico. As estimativas de efeito agrupadas serão calculadas a partir das pontuações das mudanças entre a linha de base e o final das intervenções. O tamanho do efeito será expresso em Cohens e apresentado como diferenças médias padronizadas e os cálculos serão realizados utilizando modelos de efeitos aleatórios. A heterogeneida-de estatística será avaliada pela estatística Q de Cochran e pelo teste de inconsistência I². As meta-análises serão realizadas usando OpenMeta[Analyst]

Prevalence of responders of a school intervention at physical fitness and mental health of children: a quasi-experimental study

Abstract Aim: to verify the effect of a physical education program at school on physical fitness and mental health in children and to determine the individual prevalence of responders. Methods: This is a quasi-experimental study, developed with 67 children aged between 6 and 11 years old. (8.09 ± 1.81). A 21-week intervention was performed, that intervention condition (IC) consisted of sports and circuit training, and nutritional education. For the control condition (CC) classes followed to the Common Curricular National Base. The following variables were evaluated at baseline and post-intervention: physical fitness and mental health through the strength and difficulties questionnaire. Mixed analysis of variance and the prevalence of responders were used for statistical analysis. Results: The main results indicate that there were improvements in the IC in the components of physical fitness (cardiorespiratory fitness, speed, and agility) and mental health indicators (total difficulties, emotional symptoms, problems with peers, and prosocial behavior) after a school physical education program in comparison with the CC. Concerning the prevalence of responders between groups, it was found differences in cardiorespiratory fitness (CC: 33.33%; IC: 65.38%), agility (CC: 36.66%; IC: 73.07%), speed (CC: 43.33%; IC: 79.16%), emotional symptoms (CC: 28.57%; IC: 50.00%), and prosocial behavior (CC: 17.14%; IC: 46.87%). Conclusion: It is reinforced that well-planned physical education classes and simple intervention programs can be adopted at the school level and are capable of promoting children's physical and mental health.

Caracterización de los estilos de vida en dueñas de casa chilenas: análisis de la Encuesta Nacional de Salud 2009-2010 / Lifestyles of Chilean housewives: analysis of the 2009-2010 Chilean Health Survey

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.

Relación entre niveles de actividad física y sedentarismo con síndrome metabólico. ENS Chile 2009-2010 / Relationship between levels of physical activity and sedentarism with metabolic syndrome. ENS Chile 2009-2010

Resumen: Objetivo: Asociar una nueva e integradora clasificación de actividad física (AF) y sedentarismo con riesgo de síndrome metabólico (SM) en una muestra representativa de adultos chilenos. Material y métodos: Se incluyeron 5040 participantes de la Encuesta Nacional de Salud de Chile 2009-2010. Fueron creadas cuatro categorías mediante una combinación entre niveles de AF y sedentarismo (SED) usando el cuestionario GPAQ. El SM fue definido según las normas del NCEP ATP-III. Resultados: Se observa una menor probabilidad de presentar SM sólo en las categorías que cumplen con las recomendaciones internacionales de AF (p<0.05), "activo y bajo-SED" (RM=0.72 [0.57 a 0.91]) y "activo y alto-SED" (RM=0.63 [0.49 a 0.81]). El nivel de sedentarismo (alto/bajo) no se asoció con una reducción significativa de SM en ninguno de los grupos. Conclusiones: Este tipo de clasificación demuestra que la principal estrategia para reducir el riesgo de SM debiera estar asociada con cumplir las recomendaciones de AF.

Abstract: Objective: To use a new methodology to classify the level of physical activity (PA) by combining the levels of PA and sedentary time (SED) in order to establish its association with metabolic syndrome (MS). Materials and methods: A representative sample of Chilean adults (≥18 years old) who participated in the National Health Survey (ENS 2009-2010) was included in this study (n=5 040). Four categories were created using a combination of PA and SED levels through the GPAQ questionnaire. MS was defined according to the norms established by NCEP ATP-III. Results: A lower probability of MS was observed only in the categories that comply with the international recommendations of PA, "active and low-SED" (OR=0.72 [0.57 to 0.91]) and "active and high-SED" (OR=0.63 [0.49 to 0.81]). While the level of SED (high/low) was not associated with a significant reduction of MS in any of the groups. Conclusions: This type of classification demonstrates that the main strategy to reduce the risk of MS should be associated with compliance with the recommendations of PA.

Influencia de la edad sobre el cumplimiento de las recomendaciones de actividad física: Resultados de la Encuesta Nacional de Salud en Chile 2009-2010 / Adherence to physical activity recommendations across age categories: Findings from the 2009-2010 Chilean National Health Survey

RESUMEN A pesar de que la actividad física (AF) es un factor protector contra las enfermedades crónicas no transmisibles, un gran porcentaje de la población no cumple los niveles mínimos recomendados. El objetivo fue investigar como varían los niveles de práctica de AF entre los diferentes grupos etarios en la población chilena. Se incluyeron 5.133 participantes de la Encuesta Nacional de Salud 2009-2010. La AF fue determinada utilizando el cuestionario GPAQ. La inactividad física fue definida como <600 MET/min/semana de AF moderada a vigorosa. La asociación entre AF y edad fue investigada por sexo mediante regresión logística. Las mujeres presentaron una mayor probabilidad de ser físicamente inactivas en comparación a los hombres (p<0,0001). Al analizar la prevalencia de inactividad física por sexo y grupo etario, esta cambió ligeramente entre los 20 a 59 años, pero a partir de los 60 se observó un incremento importante en la prevalencia llegando a 63% y 56% para mujeres y hombres >80 años, respectivamente. Los resultados obtenidos confirman la necesidad de seguir fomentando la práctica regular de AF física a través de todo el ciclo vital, pero en especial sobre los 60 años, ya que este grupo presenta una mayor probabilidad de ser físicamente inactivo.

ABSTRACT Although physical activity (PA) is a protective factor against non-communicable diseases, there is an important proportion of the population who do not meet PA guidelines. Our aim was to investigate how adherence to PA guidelines varies across different age groups in the Chilean population. 5,133 participants from the 2009-2010 Chilean Health Survey were included in this study. PA was measured using the Global Physical Activity Questionnaire (GPAQ). Physical inactivity was defined as <600 MET/min/week of moderate to vigorous intensity PA. Logistic regression was used to investigate the association of PA with age. The main finding of this shows that women were more likely to be inactive than men (p<0.0001). Physical inactivity prevalence varied slightly between 20 and 59 years. However, among those individuals aged >60 years the prevalence increased markedly, reaching 63% and 56% for women and men aged >80 years, respectively. These findings confirm the necessity of promoting PA across the lifespan, but more importantly, these results suggest that more promotion and opportunities for engaging in PA should be created especially for older adults, who are more likely to be physically inactive.

Tiempo destinado a estar sentado y niveles de adiposidad ¿Cuál es su efecto sobre el desarrollo de diabetes mellitus tipo 2? / The joint effect of sitting time and obesity on the odds of developing type 2 diabetes

Background: Obesity and sedentary behavior are risk factors acting independently in the development of type 2 diabetes. Aim: To investigate whether the association between diabetes and obesity is modified by the levels of sitting time (ST) in the Chilean population. Material and Methods: We included 4,611 participants from the cross-sectional 2009-2010 Chilean National Health Survey in this study. Diabetes was determined as fasting glucose levels ≥126 mg/dl. Body mass index (BMI) and waist circumference (WC) were measured using standardized protocols. Sitting time was assessed using the Global Physical Activity Questionnaire. The association among diabetes, obesity and ST was determined using logistic regression. Results: The odds for diabetes increased by 3.1-fold in people with high levels of ST and obesity in comparison to those with low levels of ST and normal BMI (Odds ratio (OR): 4.17 [95% confidence intervals (CI): 2.87 to 6.05], P < 0.01). The odds for diabetes increased by 2.7- fold in highly sedentary subjects with central obesity (OR: 3.73 [95% IC: 2.61 to 5.33], P < 0.01) in comparison to those with low levels of ST and normal WC. Conclusions: Elevated levels of sitting time and obesity are associated with a higher odds of developing diabetes.

Comparación de los niveles de actividad física durante la vida universitaria / Comparison of the physical activity levels during the university life

Background: A high percentage of Chilean university students are inactive. Aim: To determine differences in physical activity (PA) levels and energy expenditure in a group of university students according to their length of stay in the university. Material and Methods: We studied 56 students aged 22 ± 2 years (29 women). They wore a triaxial accelerometer during seven days, determining steps/day, steps/min, sedentary time and PA levels. Participants also answered a PA questionnaire. Their weight and height were measured. They were divided in two groups according to the time spent at university (1-2 years and 3-5 years). Results: No significant differences in energy expenditure were observed between both groups of students. The number of steps/day and steps/ min was significantly higher in the group with 3 to 5 years in the university than their counterparts with 1-2 years. Conclusions: As the university years increase, there is a tendency to increase the time spent walking (18.3%) but without an increase in the moderate-vigorous PA.

Factores asociados a inactividad física en Chile: resultados de la Encuesta Nacional de Salud 2009-2010 / Correlates of physical inactivity: Findings from the Chilean National Health Survey 2009-2010

Background: Physical inactivity is an important risk factor for cardiovascular diseases. Aim: To identify factors associated with physical inactivity in Chilean adults. Material and Methods: Participants from the Chilean Health Survey (5,133 individuals) were included in this study. Physical activity was measured using the Global physical activity questionnaire (GPAQ). Physical inactivity was defined as < 600 MET. min.week−1 of moderate to vigorous intensity physical activity. Logistic regression was used to identify correlates of physical inactivity. Results: The main finding of this study were that women (odds ratio (OR): 1.51 [95% confidence intervals (CI): 1.32-1.72]) were more likely to be inactive compared to men and that older adults were more likely to be inactive than their younger or middle age counterparts (OR: 3.06 [95% CI: 2.45-3.82]). Other correlates of physical inactivity were individuals with obesity (OR: 1.43 [95% CI: 1.20-1.70]), diabetes (OR: 1.96 [95% CI: 1.61-2.38]), hypertension (OR: 1.72 [95% CI: 1.50-1.97]), metabolic syndrome (OR: 1.42 [95% IC: 1.18-1.70]), a low education level (OR: 1.26 [95% CI: 1.06-1.49]) and higher levels of sedentary behavior (OR: 2.77 [95% CI: 2.36-3.25]). Conclusions: Women, older people and sedentary subjects with chronic non-transmissible conditions are at higher risk of being physically inactive.

Mayores niveles de transporte activo se asocian a un menor nivel de adiposidad y menor riesgo de obesidad: resultados de la Encuesta Nacional de Salud 2009-2010 / Association of active commuting with obesity: findings from the Chilean National Health Survey 2009-2010

Background: Active commuting is associated with a lower risk for obesity in developed countries. Aim: To investigate the association between active commuting and obesity risk in Chile. Material and Methods: Active commuting was measured using the Global Physical Activity Questionnaire (GPAQ v2) in 5,293 participants from the Chilean National Health Survey 2009-2010. Body mass index (BMI) and waist circumference (WC) were the study outcomes. The association between active commuting and obesity was investigated using linear and logistic regression analysis. Results: Thirty four percent of responders [95% confidence intervals (CI): 32.6-35.1] were passive commuters. Active commuters had a lower BMI and WC than their passive counterparts. Thirty minutes increment in active commuting were associated with a −0.20 kg.m-2 lower BMI [95% CI: −0.33 to −0.07, p < 0.01] and a −076 cm lower WC [95% CI: −1.08 to −0.43, p < 0.01]. The odds of having a BMI > 25 kg.m-2 was 0.93 [95% CI: 0.88 to 0.98, p = 0.01] per every 30 minutes' increment in active commuting, whereas the odds for central obesity was 0.87 [95% CI: 0.82 to 0.92, p < 0.01]. Conclusions: Active commuting is associated with a lower adiposity and lower risk for obesity in Chilean adults.

El sedentarismo se asocia a un incremento de factores de riesgo cardiovascular y metabólicos independiente de los niveles de actividad física / Sedentary lifestyle is associated with metabolic and cardiovascular risk factors independent of physical activity

Background: Sedentary behavior is a main risk factor for cardiovascular disease and mortality. Aim: To investigate the association between sedentary behavior and metabolic and cardiovascular risk factors. Material and Methods: We assessed 322 participants aged between 18 to 65 years. Physical activity and sedentary behavior were measured with accelerometers (Actigraph®). Body mass index (BMI), waist circumference, percentage of body fat, diet and blood markers (glucose, lipid profile, insulin and HOMA-IR) were measured with standardized protocols. Results: Thirty four percent of participants were physically inactive and spent on average 8.7 h/day on sedentary activities. Per one hour increase in sedentary behavior there were significant adverse changes in glucose (4.79 mg/dl), insulin (2.73 pmol/l), HOMA-IR (0.75), BMI (0.69 kg/m²), waist circumference (1.95 cm), fat mass (1.03%), total cholesterol (9.73 mg/dl), HDL-cholesterol (-3.50 mg/dl), LDL-cholesterol (10.7 mg/dl) and triglycerides (12.4 mg/dl). These findings were independent of main confounding factors including total physical activity, dietary factors, BMI and socio-demographics. Conclusions: The detrimental effect of sedentary behaviors on cardiometabolic and obesity-related traits is independent of physical activity levels. Therefore, reducing sedentary time should be targeted in the population apart from increasing their physical activity levels.

An integrative methodology for classifying physical activity level in apparently healthy populations for use in public health / Uso de un método integrador para clasificar el nivel de actividad física de grupos de población aparentemente sanos y su aplicación en la salud pública / Metodologia integrativa para classificar o nível de atividade física em populações aparentemente saudáveis para uso em saúde pública

ABSTRACT Physical inactivity is one of the most important risk factors contributing to morbidity and mortality in the world, although sedentary behavior (SB), low-intensity physical activity (LIPA), and shorter sleep duration have also been associated with various chronic diseases and physiopathological conditions that may affect health, irrespective of one's level of physical activity (PA). Current methods to evaluate and classify the PA level in the population appear to be limited, as they primarily focus on time spent performing moderate-to-vigorous PA (MVPA). The aim of this article is to analyze the scientific literature in regard to various combinations of patterns among sleep, SB, LIPA, and MVPA, in order to propose a more integrative PA classification in apparently healthy children, adolescents, and adults. In general, the most common classification is composed of four categories that combine MVPA with SB level as follows: i) "physically active" or "physically inactive" (meets or does not meet weekly MVPA recommendations) and ii) "high SB" or "low SB" (depending on amount of accumulated sedentary time per day). There is a consensus regarding the classification of physically active or not, but agreement has not been reached on the classification of a high SB or low SB level. This new, integrative approach appears to be an appropriate methodological proposal for categorizing the level of PA, with the aim of providing health professionals and researchers a more comprehensive vision of PA behaviors among the population.

RESUMEN La inactividad física es uno de los factores de riesgo más importantes que aumentan la morbilidad y mortalidad en el mundo, aunque el sedentarismo, la actividad física leve y una menor duración del sueño también se han asociado con diversas afecciones fisiopatológicas y enfermedades crónicas que pueden afectar la salud, independientemente del nivel de actividad física. Los métodos usados hoy en día para evaluar y clasificar el nivel de actividad física de la población parecen tener limitaciones, pues se centran principalmente en el tiempo dedicado a la actividad física de moderada a vigorosa. El objetivo de este artículo es analizar la bibliografía científica relacionada con diversas combinaciones de hábitos en lo referente al sueño, el sedentarismo, la actividad física leve y la actividad física de moderada a vigorosa, a fin de proponer una clasificación más integradora de la actividad física que realizan niños, adolescentes y adultos aparentemente sanos. En general, la clasificación más común consta de cuatro categorías que combinan la actividad física de moderada a vigorosa con el nivel de sedentarismo de la siguiente manera: 1) "físicamente activo" o "físicamente inactivo" (sigue o no las recomendaciones sobre cuánta actividad física de moderada a vigorosa debe realizarse cada semana); y 2) "nivel alto de sedentarismo" o "nivel bajo de sedentarismo", dependiendo de la cantidad de tiempo dedicado a actividades sedentarias que se acumule por día. Hay consenso sobre la clasificación de físicamente activo o físicamente inactivo, pero no se ha llegado a un acuerdo con respecto la clasificación de un nivel alto o bajo de sedentarismo. Este enfoque nuevo e integrador parece ser una propuesta metodológica apropiada para clasificar el nivel de actividad física, con el objetivo de proporcionar a investigadores y profesionales de la salud una visión más amplia del comportamiento de la población frente a la actividad física.

RESUMO A inatividade física é um importante fator de risco contribuinte para a morbidade e a mortalidade em todo o mundo, embora o comportamento sedentário (CS), a atividade física de baixa intensidade (AFBI) e a redução da duração de sono estejam também associados a diversas doenças crônicas e estados fisiopatológicos potencialmente prejudiciais à saúde, qualquer que seja o nível de atividade física (AF). As metodologias atuais para avaliar e classificar o nível de AF de uma população têm limitações porque se baseiam sobretudo no tempo dispendido em AF de intensidade moderada a vigorosa (AFMV). O propósito deste artigo é examinar a literatura científica quanto às diversas combinações de padrões de sono, CS, AFBI e AFMV a fim de propor uma classificação de AF mais integrativa para crianças, adolescentes e adultos aparentemente saudáveis. A classificação de uso geral está dividida em quatro categorias que combinam AFMV com o nível de CS: i) fisicamente ativo ou fisicamente inativo (satisfaz ou não satisfaz os níveis recomendados de AFMV semanal) e ii) nível alto ou nível baixo de CS (segundo o tempo sedentário acumulado por dia). Existe consenso quanto à classificação de fisicamente ativo ou inativo, mas não quanto à classificação de nível alto ou baixo de CS. Esta nova abordagem integrativa é possivelmente uma proposição metodológica adequada para categorizar o nível de AF, pois oferece aos profissionais da saúde e pesquisadores uma concepção mais ampla dos comportamentos de atividade física na população.

Altos niveles de adiposidad se asocian a un deterioro en la salud metabólica en adultos chilenos / Higher adiposity levels are associated with detrimental metabolic health in Chilean adults

RESUMEN Antecedentes: El exceso de grasa corporal es uno de los principales factores de riesgo de enfermedades cardiometabólicas. Objetivo: Investigar las asociaciones entre indicadores de adiposidad y metabólicos en población adulta chilena. Métodos: Estudio observacional de corte transversal en 475 adultos, a quienes se evaluó el índice de masa corporal (IMC), perímetro cintura (PC) y porcentaje de masa grasa (%MG). Se midió presión arterial, glicemia, insulina, HOMA-IR, colesterol total, triglicéridos, colesterol HDL y LDL, alanina-amino transpeptidasa, gama-glutamil transpeptidasa, leptina y proteína C-reactiva ultra sensible (PCRus). La asociación entre indicadores de adiposidad y marcadores metabólicos fue determinada mediante regresión lineal múltiple. Resultados: Los tertiles superiores de IMC, PC y %MG se asociaron significativamente (p< 0,05) con niveles bajos de colesterol HDL y altos de insulina, HOMAIR, triglicéridos, colesterol total, colesterol LDL, ALT, GGT, PCRus y leptina; esto para ambos sexos. Se observó además que los valores de presión arterial sistólica y presión arterial diastólica, fueron significativamente mayores en mujeres en relación a un mayor IMC. Conclusión: A medida que aumentó el nivel de adiposidad, se deterioran los marcadores de salud cardiovascular y metabólica, independientemente del indicador de adiposidad empleado.

ABSTRACT Background: Adiposity is positively associated with metabolic and inflammatory markers, which increase the risk of developing metabolic disease related to obesity. Aim: To investigate the association between adiposity markers and metabolic health in Chilean adults. Methods: We conducted a cross-sectional study with 475 participants. Body mass index (BMI), waist circumference (WC) and body fat (using 4 skinfold) were measured. The outcomes of interest were blood pressure, fasting glucose, insulin, HOMA-IR, total cholesterol, triglycerides (TG), HDL and LDL cholesterol,γ-glutamyltransferase (GGT), alanine aminotransferase (ALT), leptin and high sensitive C-reactive protein (hsCRP). The association between adiposity and metabolic outcomes were investigated using multiple linear regression analysis. Results: Individuals in the highest tertile for BMI, WC and body fat had a lower concentration of HDL-cholesterol and higher concentration of insulin, HOMA-IR, TG, LDL and total cholesterol, GGT, ALT, leptin and hsCRP. Blood pressure was higher with increasing BMI in females only. There was no significant association between fasting glucose and any of the adiposity markers. Conclusion: Higher adiposity levels were associated with a detrimental metabolic health. The effect of higher BMI, WC and body fat were similar across metabolic markers.

Ser físicamente activo modifica los efectos nocivos del sedentarismo sobre marcadores de obesidad y cardiometabólicos en adultos / Being physically active modifies the detrimental effect of sedentary behavior on obesity and cardiometabolic markers in adults

Background: Sedentary behavior is a major risk factor for cardiovascular disease and mortality. Aim: To investigate whether the associations between sedentary behavior and cardiometabolic markers differs across physical activity levels. Materials and Methods: Cross sectional study of 314 participants aged 18 to 65 years. Body mass index (BMI) and waist circumference were measured, and body fat was derived from the sum of four skinfolds. Physical activity was measured objectively using accelerometers (Actigraph GT1M, USA®). A fasting blood sample was obtained to measure glucose, insulin, HOMA-IR, lipid profile and high sensitive C reactive protein (hsCRP). Those participants with an activity level > 600 MET.min-1.week-1 were classified as physically active. Results: Thirty four percent of participants were physically inactive and spent an average of 8.7 h.day-1 in sedentary pursuits. Physically inactive individuals had poorer cardiometabolic health than their physically active counterparts. Per one hour decrease in overall sedentary behavior, there was a significant improvement in glucose (-8.46 and -4.68 mg.dl-1), insulin (-2.12 and -1.77 pmol.l-1), HOMA-IR (-0.81 and -0.56) BMI (-0.93 and -0.62 kg.m-2) and waist circumference (-2.32 and -1.65 cm) in physically active and inactive participants, respectively. Conclusions: Being physically active may modify the detrimental effects of sedentary behavior on cardiometabolic and obesity-related traits.

Fitness cardiorrespiratorio se asocia a una mejora en marcadores metabólicos en adultos chilenos / Inverse association of cardiorespiratory fitness with cardiovascular risk factors in Chilean adults

Background: A high level of cardiorespiratory fitness (CRF) is an important protector against cardiovascular and metabolic diseases. Aim: To explore the association of CRF with several metabolic markers and estimate the variation of these parameters by an increase of 1 MET change in CRF. Material and Methods: Cross-sectional study of 447 adults (56% women) without medical history of cardiometabolic diseases. Physical activity evaluated using accelerometry, body mass index (BMI), blood pressure, blood glucose and insulin and lipid profile were measured. HOMA-IR was calculated with fasting glucose and insulin levels. The submaximal Chester Step Test was used to measure CRF. Results: CRF was significantly associated with the level and intensity of physical activity, and all metabolic markers (p-trend < 0.05), except with diastolic blood pressure. It was estimated that 1-MET increase in CRF is associated with waist circumference (β -0.32 cm), fat mass (β -0.22%), insulin (β -0.67 pmol.l-1), HOMA-IR (β -0.17) and HDL cholesterol (β +1.46 mg.dl-1). All these associations were independent of main covariates such as age, sex, education, smoking and body mass index. Conclusions: A higher level of CRF is inversely associated with several metabolic markers that are risk factors for cardiovascular disease.

Un mayor nivel de actividad física se asocia a una menor prevalencia de factores de riesgo cardiovascular en Chile: resultados de la Encuesta Nacional de Salud 2009-2010 / Higher physical activity levels are associated with lower prevalence of cardiovascular risk factors in Chile

Background: Little is known about the relationship between physical activity (PA) and cardiovascular risk factors in the Chilean population. Aim: To investigate the association between different levels and intensities of PA and the prevalence of cardiovascular (CV) risk factors in Chilean adults. Material and Methods: Data from the National Health Survey 2009-10 including 5157 participants, provided by the Epidemiology Department of the Ministry of Health, was analyzed in this study. The prevalence of type 2 diabetes mellitus, hypertension, metabolic syndrome and dyslipidemia were determined using international criteria. PA levels were determined using the Global Physical Activity Questionnaire (GPAQ v2) and different levels of PA were derived from it (transport-related, moderate and vigorous PA). Quartiles of PA were determined to investigate the association between PA and cardiovascular risk factors. Results: Twenty three percent of women and 17.1% of men did not meet the PA recommendation (≥ 600 METs.min.week-1). When prevalence of CV risk factors were compared between inactive individuals (< 600 METs.min.week-1) and active individuals (≥ 9500 METs.min.week-1) a significantly lower prevalence of diabetes mellitus (6.2% and 10%), hypertension (18.0% and 12.4%) and metabolic syndrome (8.9% and 12.1%) for women and men, respectively, was found in the active participants. Similar results were found for high versus low transport-related PA. Conclusions: Increasing levels of PA are associated with a significantly lower frequency of cardiovascular risk factors in Chilean adults.

Influencia de las clases de educación física sobre el nivel de actividad física medido a través de una aplicación móvil en adolescentes / Influence of physical education classes on the level of physical activity measured through a mobile application in adolescents

La literatura científica ha demostrado a través de diversos métodos (cuestionarios y acelerómetros, principalmente) que las clases de educación física (EF) influyen positivamente en el logro de las recomendaciones de actividad física (AF) en la población escolar. Sin embargo, el uso de nuevas tecnologías como los teléfonos móviles o smartphone, parecen ser una interesante herramienta de bajo costo que también podrían ayudar a determinar el nivel de AF. Por tanto, el objetivo del presente estudio fue describir como influye la clase de EF en el número de pasos diarios en escolares que utilizaron una aplicación móvil “RuntasticPedometer” para monitorear dicha variable. La muestra estuvo compuesta por 50 estudiantes (edad media de 14.1 +/-1.6 años) pertenecientes al Instituto de Educación Secundaria “Melchor de Macanaz” de la localidad de Hellín (Albacete, España). Tras analizar los datos, se observaron diferencias significativas (p<0.05) durante los días en que los escolares realizaron la clase de EF y los que no (9.950 vs. 8.023 pasos/día,respectivamente). Además, la variación entre los días con y sin EF también fueron estadísticamente diferentes entre niños y niñas (2.644 vs. 1.579 pasos/día, respetivamente).Finalmente, se podría concluir que las clases de EF parecen influir positivamente en el aumento del número de pasos en escolares, lo que elevaría las posibilidades de que estos niños y niñas logren los parámetros mínimos de AF recomendada por las diversas organizaciones de salud. Por otro lado, cabe señalar que el uso de nuevas tecnologías de uso masivo como los smartphone, podrían ser una interesante herramienta a validar orientadas al monitoreo de la AF.

The scientific literature has demonstrated through various methods (questionnaires and accelerometers, mainly), the classes of physical education (PE) positively influence the achievement of the recommendations of physical activity (PA) in the school population. However, the use of new technologies such as mobile phones or smartphone, appear to be an interesting inexpensive tool that could also help determine the level of AF. Therefore, the objective of this study was to describe as PE class influences in the daily number of steps in school who used a mobile application "Runtastic Pedometer" to monitor the variable. The sample consisted of 50 students (mean age 14.1 +/- 1.6 years) belonging to the Institute of Secondary Education "MelchorMacanaz" from the Hellín (Albacete, Spain). After analyzing the data, significant differences (p <0.05) were observed during the days when the school made PE class and those without (8,023 vs. 9,950 steps / day, respectively). Moreover, the variations between days with and without EF were also statistically different between boys and girls (2,644 vs. 1,579 steps/day,respectively). Finally, one could conclude that PE classes seem positively influence the increase in the number of steps in school raising the chances that these children achieve the minimum standards recommended HF various health organizations. On the other hand, it notes that the use of new technologies in widespread use as the smartphone could be an interesting tool to validate oriented monitoring AF.