Food insecurity in Chilean university students during the COVID-19 pandemic

Background: Food and nutrition were affected by the COVID-19 pandemic, increasing levels of food insecurity. University students were a risk group for food insecurity due to the closure of educational establishments where they received their main meals. Aim: To assess food insecurity among Chilean public university students before and during the COVID-19 pandemic. Material and Methods: The study had a non-probabilistic before-and-after design. Undergraduate students from all colleges at the university were invited to answer an online survey about food insecurity, devised based on FAO Food Insecurity Experience Scale. Results: Nine hundred and one students answered the survey. The prevalence of moderate/severe food insecurity increased from 9.5% to 14.3% before and during the pandemic, respectively. Forty two percent (n = 196) of student households became food insecure during the sanitary crisis. Students commented on the positive and negative aspects of the pandemic in their eating behaviors. Conclusions: Undergraduate students are vulnerable to food insecurity. Mitigation actions should be carried out when educational establishments are closed.

Antecedentes: La alimentación y la nutrición se están viendo afectadas por la pandemia por COVID-19, aumentando los niveles de inseguridad alimentaria. Un grupo susceptible a la inseguridad alimentaria son los estudiantes universitarios debido al cierre de los establecimientos educativos donde ellos pueden recibir sus alimentos principales. Objetivo: Evaluar la inseguridad alimentaria de los estudiantes de una universidad pública de Chile, antes y durante la pandemia por COVID-19. Material y Métodos: El estudio tuvo un diseño de antes y después, no probabilístico. Se invitó a participar a estudiantes universitarios de todas las facultades de la universidad a contestar un cuestionario en línea, desarrollado basado en la escala de experiencia de inseguridad alimentaria de la FAO. Resultados: Novecientos y un estudiantes respondieron la encuesta. En estos estudiantes, la prevalencia de inseguridad alimentaria moderada/grave aumentó de 9,5% a 14,3% antes y durante la pandemia, respectivamente. El 42,3% (n = 196) de los hogares estudiantiles pasó a tener inseguridad alimentaria durante la crisis sanitaria. Los estudiantes comentaron aspectos positivos y negativos de la pandemia en sus conductas alimentarias. Conclusiones: Estos resultados reflejan que estos estudiantes son vulnerables para inseguridad y amerita acciones de mitigación cuando los establecimientos educativos están cerrados.

Food insecurity in Chilean university students during the COVID-19 pandemic.

BACKGROUND: Food and nutrition were affected by the COVID-19 pandemic, increasing levels of food insecurity. University students were a risk group for food insecurity due to the closure of educational establishments where they received their main meals. AIM: To assess food insecurity among Chilean public university students before and during the COVID-19 pandemic. MATERIAL AND METHODS: The study had a non-probabilistic before-and-after design. Undergraduate students from all colleges at the university were invited to answer an online survey about food insecurity, devised based on FAO Food Insecurity Experience Scale. RESULTS: Nine hundred and one students answered the survey. The prevalence of moderate/severe food insecurity increased from 9.5% to 14.3% before and during the pandemic, respectively. Forty two percent (n = 196) of student households became food insecure during the sanitary crisis. Students commented on the positive and negative aspects of the pandemic in their eating behaviors. CONCLUSIONS: Undergraduate students are vulnerable to food insecurity. Mitigation actions should be carried out when educational establishments are closed.

The influence of body composition on the six-minute walk test in Chilean preschool and school children.

INTRODUCTION: Background: the six minutes' walk test (6MWT) measures submaximal physical activity. Objective: this study determines the association of children´s nutritional status and body composition with the results of the 6MWT. Methods: a sample of 1419 Chilean children, 4 to 10 years of age, were assessed including anthropometry, body composition by validated equations, the 6MWT test, and in 50 % of the sample heart rate prior the test, at one minute into the test, and at one minute posttest with a Polar watch. Results: the distance walked ranged from 473.1 ± 47.8 meters in preschool children to 584.2 ± 65.7 meters in school children. In heart rate there was a significant difference between obese and eutrophic children. The distance walked in the 6MWT was positively associated with fat-free mass (p < 0.05) and BMI (R2 = 0.49). Body composition influences 6MWT quartile distribution, as well as nutritional status. Age and height explained 49 % of the variance (R2 = 0.42 and 0.47, respectively) in the 6MWT, and there are significant differences in this variable by sex, body composition, and nutritional status. Conclusions: body composition was associated with walking performance in children. Thus, it is important to evaluate height and body composition when assessing the six-minute walk test because of this important relationship.

INTRODUCCIÓN: Introducción: el test de la marcha de seis minutos (TM6M) mide una actividad física submáxima. Este estudio evaluó el efecto del test de la marcha sobre la composición corporal y el estado nutricional en niños. Métodos: en una muestra de 1419 niños chilenos de 4 a 10 años de edad se evaluaron la antropometría, la composición corporal por ecuaciones validadas, el TM6M y, en el 50 % de la muesta, la frecuencia cardíaca mediante un reloj Polar. Resultados: la distancia caminada varió desde 473,1 ± 47,8 metros en los niños preescolares hasta 584,2 ± 65,7 metros en los escolares. En la frecuencia cardíaca hubo una diferencia significativa entre niños obesos y eutróficos. La distancia caminada se asoció positivamente con la masa libre de grasa (R2 = 0,37) y el IMC (R2 = 0,49). Por otra parte, la composición corporal varía en función de los cuartiles de composición corporal y el estado nutricional. La edad y la altura explicaron el 49 % de la varianza de la prueba (R2 = 0,42 and 0,47, respectivamente). Existen diferencias significativas en la distancia recorrida en el TM6M en función del sexo, la composición corporal y el estado nutricional. Conclusiones: composición corporal, talla e IMC se asociaron a la distancia recorrida en el TM6M. Por tanto, se sugiere medir estas variables cuando se evalúe el test de marcha de seis minutos.

El perfil del tutor clínico en los escenarios actuales / The profile of the clinical tutor in current settings

Actualmente, uno de los objetivos de la educación médica es proporcionar a los estudiantes la oportunidad de desarrollar habilidades clínicas y competencias profesionales. Por lo cual el docente tutor generador de aprendizaje debe poseer las herramientas necesarias para ello. La tutoría clínica, es una estrategia fundamental en la enseñanza de los saberes de las ciencias médicas. Considerada como educación "no formal" en contraste con la educación tradicional de las aulas, la enseñanza en los ambientes clínicos tiene su propia estructura o formas de enseñanza. En este sentido, el docente tutor debe reconocer cuáles son las funciones de la tutoría clínica, para así, establecer objetivos claros que respondan al programa de formación de un profesional y que permita la conducción de la tutoría de manera óptima, generando en el estudiante aprendizaje significativo. Esta revisión tiene por objetivo entregar información actualizada respecto al abordaje actual de la tutoría clínica en las carreras del área de salud y describir las competencias pedagógicas que debe tener un tutor clínico.

Currently, one of the goals of medical education is to provide students with the opportunity to development clinical skills and professional competencies. Therefore, the tutor generator learning must have the necessary tools to do. Clinical tutoring is a fundamental strategy in the teaching of knowledge of medical sciences. Considered as "non-formal" instruction in contrast to traditional classroom instruction, teaching in clinical settings has its own structure or forms of teaching. Therefore, the tutor teacher must recognize what are the functions of clinical tutoring, in order to establish clear objectives that respond to the training program of a professional and that allow the conductivity of the tutoring in an optimal way, generating meaningful learning in the student. This review aims to provide updated information regarding the current approach to clinical tutoring in health careers and to describe the pedagogical competencies that should have a clinical tutor.

Validación de un instrumento para evaluar consejería adolescente diferenciada en un centro de salud / Validation of an instrument for assessing adolescent counseling differentiated in a health center

RESUMEN La OMS/OPS admite que los patrones de conducta sexuales de los adolescentes y jóvenes han cambiado. Se afirma la consejería adolescente ha mostrado buenos resultados. Por ello el propósito de este estudio es evaluar un cuestionario que evaluará este tipo de intervención. Objetivos Establecer la validez de constructo y la confiabilidad de un instrumento para evaluar consejería en adolescentes asistentes al centro de salud Rucahueche. Métodos Estudio exploratorio con una muestra de 151 adolescentes entre 15 y 19 años, a los que se les aplicó un cuestionario autoadministrado. La validez de constructo y de consistencia interna fue evaluada por análisis factorial y el Alfa de Cronbach, respectivamente. Resultados El análisis factorial identificó en 3 dimensiones 10 constructos, los cuales explicaron el 62% - 67% de su variabilidad. A su vez, el análisis de consistencia interna obtuvo una puntuación de alfa de 0,934. Conclusiones El instrumento mostró evidencias de validez de constructo y de confiabilidad. Dichos análisis indican la factibilidad de aplicación del instrumento. Sin embargo, la validación del instrumento aún es un reto, debido a su relevancia para una mirada más profunda sobre la atención y la gestión en la atención de adolescentes. Por tanto, se considerará seguir haciendo estudios para explorar su dimensionalidad y validez de contenido.

ABSTRACT The WHO/PAHO admits that the sexual behavior patterns of adolescents and young people have changed. It is claimed adolescent counseling has shown good results. Therefore, the purpose of this study is to evaluate a questionnaire that will evaluate this type of intervention. Objectives To establish the construct validity and reliability of an instrument for assessing adolescent counseling attending the health center Rucahueche. Methods An exploratory study with a sample of 151 adolescents aged 15 to 19 years, who were applied a self-administered questionnaire. Construct validity and internal consistency was assessed by factor analysis and Cronbach's alpha, respectively. Results: Factor analysis identified three dimensions 10 constructs, which accounted for 62% -67% of its variability. In turn, analysis of internal consistency score was alpha of 0.934. Conclusions The instrument showed evidence of construct validity and reliability. These analyzes indícate the feasibility of the instrument. However, validation of the instrument is still a challenge, because of its relevance to a deeper look on the care and management in adolescent care. Therefore, it is deemed to continue doing studies to explore the dimensionality and content validity.

Predictive anthropometric models of total and truncal body fat in Chilean children.

OBJECTIVES: This study aimed to develop predictive anthropometric models for total and truncal body fat in Chilean children using the following anthropometric measurements: weight, height, skinfold thickness, and circumference. METHODS: This cross-sectional study included 669 Chilean children (12.0 y ± 1.3) in Tanner stage IV from the Growth and Obesity Chilean Cohort Study. Anthropometric measurements and dual-energy X-ray absorptiometry were determined to calculate total and truncal body fat. Prediction models were fitted by linear regression analysis. RESULTS: The predictive equation for log total body fat (kg) was 0.449 + 0.049 (body mass index in kg/m2) + 0.018 (triceps skinfold in mm) + 0.012 (biceps skinfold in mm) + 0.019 (brachial circumference in cm) + 0.091 (sex: 1 = boy, 2 = girl) + 0.018 (age in y). The predictive equation for log truncal fat (kg) was -2.107 + 0.046 (waist circumference in cm) + 0.010 (subscapular skinfold in mm) + 0.259 (sex: 1 = boy, 2 = girl) + 0.006 (age in y). The test of concordance between the predictive equations of total and truncal body fat with gold standard was r = 0.85 and 0.91, respectively. CONCLUSIONS: In Chilean children, the high correlation between observed and predicted values enabled us to develop predictive equations for total and truncal body fat for children.

Efectividad de la formación en tutoría clínica en nutrición / Effectiveness of training in clinical tutoring in nutrition

RESUMEN Uno de los objetivos de la enseñanza tutorial en la carrera de Nutrición y Dietética, es proporcionar a los estudiantes un espacio de aprendizaje para desarrollar habilidades clínicas y competencias profesionales. El propósito del estudio fue evaluar un programa de capacitación en tutoría clínica dirigido a tutores clínicos nutricionistas y su efecto en las percepciones de los estudiantes de práctica clínica y su desempeño profesional. Se desarrolló una intervención antes y después de capacitación en tutoría clínica en nutrición, con una muestra no probabilística (n=8 nutricionistas tutores clínicos; n='6 estudiantes). Se hizo un análisis cualitativo de codificación temática y se contrastaron las calificaciones obtenidas mediante T Student. Una vez realizada la intervención los docentes adquirieron herramientas para conducir la tutoría clínica y los estudiantes tuvieron mejores experiencias clínicas. Si bien, el rendimiento académico no mejoró (5,9±0,3; v/s 6,'±0,4; p= 0,4), los docentes percibieron mejoría en el aprendizaje. Se puede concluir que la formación de nutricionistas competentes, responsables de brindar bienestar y cuidado integral a los pacientes depende de la excelencia en la formación del cuerpo docente, que sea centrada en el estudiante y con una enseñanza de calidad que promueva el aprendizaje efectivo.

ABSTRACT One of the objectives of clinical tutoring in the Nutrition and Dietetics major is to provide students with a learning space to develop clinical skills and professional competencies. The aim of the study was to evaluate a training program in clinical tutoring aimed at clinical nutritionist tutors. The effect on students' perceptions of clinical practice and professional performance was evaluated. A pre- and post-intervention test was administered in a non-probabilistic sample (n= 8 nutritionists clinical tutors, n= 16 students). A qualitative analysis of thematic coding was done and the Student t-test was used to compare pre- posttests. Once the intervention was done, the teachers acquired tools to conduct clinical tutoring and students had better clinical experiences. Although academic performance did not improve (5.9±0.3, versus 6.1±0.4, p= 0.4), teachers perceived an improvement in learning. We can conclude that the training of competent nutritionists, responsible for providing well-being and comprehensive care to patients depends on the excellence of the teaching staff, student-centered teaching and a quality education that promotes effective learning.

A waist-to-height ratio of 0.54 is a good predictor of metabolic syndrome in 16-year-old male and female adolescents.

BACKGROUND: We aimed to determine the sensitivity and specificity of selected anthropometric indicators as predictors of cardiovascular risk in adolescents. METHODS: Cross-sectional study in 678 adolescents (16.8 y ± 0.3) from an infancy cohort. Weight, height, waist circumference (WC), and hip circumference were measured. Body mass index (BMI), waist-to-hip ratio (WHR) and waist-to-height ratio (WHtR) were estimated. MetS was diagnosed with IDF/AHA/NHLBI. Optimal cutoffs of BMI, WC, WHR, and WHtR for diagnosing MetS were determined using ROC analysis. RESULTS: In males, WHtR (0.96) had the greatest area under the ROC curve, followed by WC (0.95) and BMI (0.93). In females, BMI (0.84) had the greatest area under the ROC curve (0.84), followed by WHtR (0.83) and WC (0.83). In both sexes, the optimal WHtR cutoff for MetS diagnosis was 0.54. A BMI of 26.9 in males and 26.3 in females were the optimal cutoffs for diagnosing MetS. Finally, WC values of 92 and 81.6 cm in males and females, respectively, were the optimal cutoffs for MetS diagnosis. CONCLUSIONS: In both sexes, a WHtR value of 0.54 was a good predictor of MetS. In males and females, the optimal cutoff of BMI for Mets diagnosis was below the values for diagnosing obesity.

Impact of gaining or maintaining excessive weight in infancy on markers of metabolic homeostasis in young children: A longitudinal study in Chilean children.

Childhood obesity in Chile is one of the highest in the world. The objective of this study was to assess the impact of excessive weight gained or maintained over a 3-year period, on markers of metabolic homeostasis in young children. This is a longitudinal study which includes 243 children followed from 4 to 7 years. We assessed BMI, body fat percentage, waist circumference (WC), waist-hip ratio (WHR), waist-height (WH) and trunk fat as well as the following metabolic parameters: glucose, insulin, triglycerides, total cholesterol, LDL, HDL and metabolic risk score. Kruskal- Wallis was used to assess differences in metabolic markers by nutritional status and logistic regression to determine the effect of maintaining or gaining excess weight over the 3-year period, compared with children who maintained a normal weight. Children who were obese at both ages compared with those who were normal weight, had a significantly higher WC, serum concentrations of total fat, total cholesterol, triglycerides, LDL cholesterol and metabolic risk score (P < 0.05). Children who were overweight or obese at 4 and 7 years, had a greater risk of having a high WC (OR: 3.37; P = 0.03), total cholesterol (OR: 4.17; P < 0.003), triglycerides (OR: 1.96; P = 0.04); thus a higher metabolic risk score (OR: 3.21; P = 0.003). Excess weight maintained over time in early childhood, significantly increases the risk of having higher serum biomarkers of cardiovascular risk, which in turn determines the magnitude of cardiovascular and metabolic risks later in life.

[Physical fitness and insulin sensitivity in a group of obese children from 8 to 13 years of age by puberal state]. / Condición física y sensibilidad insulínica en un grupo de escolares obesos de 8 a 13 años según estado puberal.

INTRODUCTION: Insulin resistance is the most common metabolic disorder associated with obesity and highest cardiometabolic risk in children. If the inadequate physical condition is added, they have a high risk of developing cardiometabolic complications at an early age. OBJECTIVE: To evaluate physical fitness and insulin sensitivity in obese school children of 8-13 years of age from three public schools in the Metropolitan Region of Santiago. METHODS: the study was carried out in 61 obese school children (25 Tanner I-II y 36 Tanner III-V). Anthropometric measures, Tanner stages, body composition (using 4-compartment model), physical fitness with the six-minute test and laboratory indicators, glucose, insulin and HOMA-IR, were measured. Metabolic syndrome was diagnosed according to the criteria of Cook. RESULTS: Obese prepubertal and pubertal children and adolescents showed inadequate physical fitness, refl ected in the distance and heart rate during and after the six-minute test. In turn, the sample has a high prevalence of insulin resistance in conjunction with metabolic syndrome. CONCLUSIONS: Regardless of the pubertal status, obese schoolchildren have a poor physical fitness and decreased insulin sensitivity reflected in a compensatory hyperinsulinemia.

INTRODUCCIÓN: la resistencia a la insulina es la alteración metabólica más común relacionada con la obesidad y se asocia a un mayor riesgo cardiovascular en la edad pediátrica. Si a esto se suma una inadecuada condición física, existe un alto riesgo de desarrollar complicaciones cardiometabólicas tempranamente. OBJETIVO: evaluar la condición física y la resistencia insulínica en escolares obesos de 8 a 13 años de edad, seleccionados en tres establecimientos públicos de la Región Metropolitana de Santiago. MÉTODOS: el estudio se llevó a cabo en 61 escolares obesos (25 Tanner I-II y 36 Tanner III-V). Se realizaron mediciones antropométricas, etapas de Tanner, composición corporal con el modelo de cuatro compartimentos, condición física con el test de seis minutos (TM6min) e indicadores de laboratorio, glicemia, insulinemia y HOMA-IR. Se diagnosticó síndrome metabólico según criterio de Cook.RESULTADOS: los escolares y adolescentes obesos prepúberes y púberes presentan una inadecuada condición física, reflejada en la distancia recorrida y en la frecuencia cardiaca durante y posterior al TM6min. A su vez, la muestra presenta una alta prevalencia de resistencia a insulina en conjunto con síndrome metabólico. CONCLUSIONES: independientemente del estado puberal, los escolares obesos presentan una baja condición física y una disminución de la sensibilidad a la insulina, que se refleja en un hiperinsulinismo compensatorio.

Condición física y sensibilidad insulínica en un grupo de escolares obesos de 8 a 13 años según estado puberal / Physical fitness and insulin sensitivity in a group of obese children from 8 to 13 years of age by puberal state

Introducción: la resistencia a la insulina es la alteración metabólica más común relacionada con la obesidad y se asocia a un mayor riesgo cardiovascular en la edad pediátrica. Si a esto se suma una inadecuada condición física, existe un alto riesgo de desarrollar complicaciones cardiometabólicas tempranamente. Objetivo: evaluar la condición física y la resistencia insulínica en escolares obesos de 8 a 13 años de edad, seleccionados en tres establecimientos públicos de la Región Metropolitana de Santiago. Métodos: el estudio se llevó a cabo en 61 escolares obesos (25 Tanner I-II y 36 Tanner III-V). Se realizaron mediciones antropométricas, etapas de Tanner, composición corporal con el modelo de cuatro compartimentos, condición física con el test de seis minutos (TM6min) e indicadores de laboratorio, glicemia, insulinemia y HOMA-IR. Se diagnosticó síndrome metabólico según criterio de Cook. Resultados: los escolares y adolescentes obesos prepúberes y púberes presentan una inadecuada condición física, reflejada en la distancia recorrida y en la frecuencia cardiaca durante y posterior al TM6min. A su vez, la muestra presenta una alta prevalencia de resistencia a insulina en conjunto con síndrome metabólico. Conclusiones: independientemente del estado puberal, los escolares obesos presentan una baja condición física y una disminución de la sensibilidad a la insulina, que se refleja en un hiperinsulinismo compensatorio (AU)

Introduction: Insulin resistance is the most common metabolic disorder associated with obesity and highest cardiometabolic risk in children. If the inadequate physical condition is added, they have a high risk of developing cardiometabolic complications at an early age. Objective: To evaluate physical fitness and insulin sensitivity in obese school children of 8-13 years of age from three public schools in the Metropolitan Region of Santiago. Methods: the study was carried out in 61 obese school children (25 Tanner I-II y 36 Tanner III-V). Anthropometric measures, Tanner stages, body composition (using 4-compartment model), physical fitness with the six-minute test and laboratory indicators, glucose, insulin and HOMA-IR, were measured. Metabolic syndrome was diagnosed according to the criteria of Cook. Results: Obese prepubertal and pubertal children and adolescents showed inadequate physical fitness, reflected in the distance and heart rate during and after the six-minute test. In turn, the sample has a high prevalence of insulin resistance in conjunction with metabolic syndrome. Conclusions: Regardless of the pubertal status, obese schoolchildren have a poor physical fitness and decreased insulin sensitivity reflected in a compensatory hyperinsulinemia (AU)

Multivariate Adaptative Regression Splines (MARS), una alternativa para el análisis de series de tiempo / Multivariate Adaptive Regression Splines (MARS), an alternative for the analysis of time series

Multivariate Adaptative Regression Splines (MARS) es un método de modelación no paramétrico que extiende el modelo lineal incorporando no linealidades e interacciones de variables. Es una herramienta flexible que automatiza la construcción de modelos de predicción, seleccionando variables relevantes, transformando las variables predictoras, tratando valores perdidos y previniendo sobreajustes mediante un autotest. También permite predecir tomando en cuenta factores estructurales que pudieran tener influencia sobre la variable respuesta, generando modelos hipotéticos. El resultado final serviría para identificar puntos de corte relevantes en series de datos. En el área de la salud es poco utilizado, por lo que se propone como una herramienta más para la evaluación de indicadores relevantes en salud pública. Para efectos demostrativos se utilizaron series de datos de mortalidad de menores de 5 años de Costa Rica en el periodo 1978-2008 (AU)

Multivariate Adaptive Regression Splines (MARS) is a non-parametric modelling method that extends the linear model, incorporating nonlinearities and interactions between variables. It is a flexible tool that automates the construction of predictive models: selecting relevant variables, transforming the predictor variables, processing missing values and preventing overshooting using a self-test. It is also able to predict, taking into account structural factors that might influence the outcome variable, thereby generating hypothetical models. The end result could identify relevant cut-off points in data series. It is rarely used in health, so it is proposed as a tool for the evaluation of relevant public health indicators. For demonstrative purposes, data series regarding the mortality of children under 5 years of age in Costa Rica were used, comprising the period 1978-2008 (AU)

[Multivariate Adaptive Regression Splines (MARS), an alternative for the analysis of time series]. / Multivariate Adaptative Regression Splines (MARS), una alternativa para el análisis de series de tiempo.

Multivariate Adaptive Regression Splines (MARS) is a non-parametric modelling method that extends the linear model, incorporating nonlinearities and interactions between variables. It is a flexible tool that automates the construction of predictive models: selecting relevant variables, transforming the predictor variables, processing missing values and preventing overshooting using a self-test. It is also able to predict, taking into account structural factors that might influence the outcome variable, thereby generating hypothetical models. The end result could identify relevant cut-off points in data series. It is rarely used in health, so it is proposed as a tool for the evaluation of relevant public health indicators. For demonstrative purposes, data series regarding the mortality of children under 5 years of age in Costa Rica were used, comprising the period 1978-2008.

Comparison of body fat calculations by sex and puberty status in obese schoolchildren using two and four compartment body composition models.

INTRODUCTION: Determine body composition changes in adiposity can assess an individual. OBJECTIVE: The objective of this study was to evaluate total body fat percentage based on two and four compartment models in obese Chilean school children, adjusting for differences in sex and puberty status. METHODS: Sixty-one obese school children (33 boys and 28 girls) between 8 and 13 years of age were evaluated. Two compartment measurements of body fat percentage considered isotope dilution, plethysmography, radiographic absorptiometry and bioelectrical impedance; using the four compartment model as a benchmark. RESULTS: Each method explained between 43-87% of the variance in body fat percentage in Tanner stage I and II children and between 78-96% in Tanner stage III and V children. In both groups of children methods differed significantly for stage I, with the exception of plethysmography. High R2 values were observed for girls in all Tanner stages. Each method explained between 34-92% of the variance in body fat percentage for girls in stages I and II and between 63-93% for stages III and V. In obese boys, R2 values were high for stages III and V. In girls and boys in Tanner stage III and V, the smallest differences were observed for isotopic dilution, and DXA (dual-energy X-ray absorptiometry) scan for stages I and II. CONCLUSIONS: For obese boys and girls, the two compartment model with isotopic dilution and DXA had the best precision and smallest differences in determining body fat percentage compared to the benchmark.

Comparison of body fat calculations by sex and puberty status in obese schoolchildren using two and four compartment body composition models / Comparación de modelos de dos y cuatro compartimentos para grasa corporal en escolares obesos según su sexo y desarrollo puberal

Introduction: Determine body composition changes in adiposity can assess an individual. Objective: The objective of this study was to evaluate total body fat percentage based on two and four compartment models in obese Chilean school children, adjusting for differences in sex and puberty status. Methods: Sixty-one obese school children (33 boys and 28 girls) between 8 and 13 years of age were evaluated. Two compartment measurements of body fat percentage considered isotope dilution, plethysmography, radiographic absorptiometry and bioelectrical impedance; using the four compartment model as a benchmark. Results: Each method explained between 43-87% of the variance in body fat percentage in Tanner stage I and II children and between 78-96% in Tanner stage III and V children. In both groups of children methods differed significantly for stage I, with the exception of plethysmography. High R2 values were observed for girls in all Tanner stages. Each method explained between 34-92% of the variance in body fat percentage for girls in stages I and II and between 63-93% for stages III and V. In obese boys, R2 values were high for stages III and V. In girls and boys in Tanner stage III and V, the smallest differences were observed for isotopic dilution, and DXA (dual-energy X-ray absorptiometry) scan for stages I and II. Conclusions: For obese boys and girls, the two compartment model with isotopic dilution and DXA had the best precision and smallest differences in determining body fat percentage compared to the benchmark (AU)

Introducción: determinar la composición corporal permite valorar cambios en la adiposidad de un individuo. Objetivo: el objetivo de este estudio fue evaluar la grasa corporal total basada en modelos de dos compartimentos (2C) y compararlos con el modelo de cuatro compartimentos (4C) en escolares chilenos obesos, considerando potenciales diferencias por sexo y desarrollo puberal. Métodos: 61 escolares obesos (33 niños y 28 niñas), de entre 8 y 13 años. La medición de la grasa corporal por 2C consideró dilución isotópica, pletismografía, absorciometría radiográfica y bioimpedanciometría; utilizando como patrón de referencia el modelo de 4 compartimentos. Resultados: cada método dio cuenta de 43-87% de la varianza para determinar el porcentaje de grasa corporal en niños en etapa I y II y 78-96% en etapa III y IV. En ambos grupos de niños, las pendientes difirieron significativamente en la etapa I, con la excepción de la pletismografía. En niñas los valores de R2 altos se observaron en todas las etapas del desarrollo puberal. Cada método dio cuenta de 34-92% de la varianza para determinar el porcentaje de grasa corporal en niñas etapa I y II y 63-93% en etapa III y IV, respectivamente. En niños obesos, los valores de R2 fueron altos, principalmente en el grupo de etapa III y IV. En niños y niñas de Tanner III y IV, las menores diferencias con el patrón de referencia fueron con dilución isotópica; en cuanto a Tanner I y II, las menores diferencias se obtuvieron con DEXA. Conclusiones: en ambos sexos, el modelo de dos compartimentos con dilución isotópica y DEXA tuvo la mayor precisión y las menores diferencias para determinar la grasa corporal en los niños y adolescentes obesos, en comparación con el patrón de referencia (AU)

Energy expenditure and intake comparisons in Chilean children 4-5 years attending day-care centres / Comparación entre el gasto y el consumo de energía en niños chilenos de 4-5 años asistentes a jardines infantiles

Introduction: the doubly labelled water (DLW) method has an accuracy of 1% and within-subject precision of 5-8%, depending on subject’s age and environments issues. Energy intake assessment is prone to errors (>15- 20%) depending in the method utilized. Objective: to quantify DLW methodology errors in four to five year olds that could affect the comparison with energy intake. Methods: energy expenditure (TEE, by DLW), was assessed during 14 days in 18 preschool children, who attended eight hours daily to day-care centres. Energy intake was determined by a combined method: food weighing during weekdays and recall after leaving the Centre (17h to sleep time) plus 24 h recall, during the weekend. Several assumptions affecting DLW total error were assessed to determine their influence in the comparison to energy intake (i.e. background variability, space ratio, proportion of water subject to fractionation, food quotient value). Results: the individual mean energy expenditure was 1 373 ± 177 kcal and the energy intake (1 409 ± 161 kcal). The overall difference between intake and expenditure was 42.9 kcal/day (limits of agreement + 259.1 to -112.3 kcal/day). TEE measurement error only explained a minor quantity (2.4%), between both measurements, and the observed mean isotope dilution space was 1.030 ± 0.010 confirming the value utilized in adults studies. Conclusions: energy expenditure data is similar to other studies in preschool children. The small difference found between energy intake and expenditure may be attributed to the applied energy intake methodology, the homogeneous diet at care centres during the week-days and the lower DLW methodology error (AU)

Introducción: el método del agua doblemente marcada (ADM) tiene una precisión del 1% y en un mismo sujeto es de 5-8%, dependiendo de la edad y el entorno del sujeto. La evaluación de la ingesta energética es propensa a errores (> 15-20%), dependiendo del método utilizado. Objetivo: cuantificar los errores metodológicos del ADM en niños de 4-5 años que podrían afectar la comparación con la ingesta de energía. Métodos: el gasto de energía (GTE, por ADM), se evaluó durante 14 días en 18 preescolares, asistentes a guarderías infantiles. La ingesta energética se determinó mediante un método combinado: pesaje de alimentos durante los días de la semana y registro después de salir del centro (17 horas en adelante), además de un recordatorio de 24 horas, durante un día del fin de semana. Resultados: el promedio individual del gasto energético total fue 1373 ± 177 kcal y la ingesta de energía (1.409 ± 161 kcal). La diferencia global entre la ingesta y el gasto fue 42,9 kcal/día. El error de medición del GET explicó una variación del 2,4%, entre ambas mediciones, y el espacio de dilución de isótopos fue 1030 ± 0.010, confirmando el valor utilizado en los estudios de adultos. Conclusiones: los datos de GET fueron similares a otros estudios realizados en niños en edad preescolar. La pequeña diferencia encontrada entre la ingesta y el gasto energético se puede atribuir a la metodología de la ingesta de energía aplicada, la dieta homogénea en los centros de atención, durante los días de la semana, y el bajo error metodológico del ADM (AU)

ENERGY EXPENDITURE AND INTAKE COMPARISONS IN CHILEAN CHILDREN 4-5 YEARS ATTENDING DAY-CARE CENTRES.

INTRODUCTION: the doubly labelled water (DLW) method has an accuracy of 1% and within-subject precision of 5-8%, depending on subject's age and environments issues. Energy intake assessment is prone to errors (>15- 20%) depending in the method utilized. OBJECTIVE: to quantify DLW methodology errors in four to five year olds that could affect the comparison with energy intake. METHODS: energy expenditure (TEE, by DLW), was assessed during 14 days in 18 preschool children, who attended eight hours daily to day-care centres. Energy intake was determined by a combined method: food weighing during weekdays and recall after leaving the Centre (17h to sleep time) plus 24 h recall, during the weekend. Several assumptions affecting DLW total error were assessed to determine their influence in the comparison to energy intake (i.e. background variability, space ratio, proportion of water subject to fractionation, food quotient value). RESULTS: the individual mean energy expenditure was 1 373 ± 177 kcal and the energy intake (1 409 ± 161 kcal). The overall difference between intake and expenditure was 42.9 kcal/day (limits of agreement + 259.1 to -112.3 kcal/day). TEE measurement error only explained a minor quantity (2.4%), between both measurements, and the observed mean isotope dilution space was 1.030 ± 0.010 confirming the value utilized in adults studies. CONCLUSIONS: energy expenditure data is similar to other studies in preschool children. The small difference found between energy intake and expenditure may be attributed to the applied energy intake methodology, the homogeneous diet at care centres during the week-days and the lower DLW methodology error.

Introducción: el método del agua doblemente marcada (ADM) tiene una precisión del 1% y en un mismo sujeto es de 5-8%, dependiendo de la edad y el entorno del sujeto. La evaluación de la ingesta energética es propensa a errores (> 15-20%), dependiendo del método utilizado. Objetivo: cuantificar los errores metodológicos del ADM en niños de 4-5 años que podrían afectar la comparación con la ingesta de energía. Métodos: el gasto de energía (GTE, por ADM), se evaluó durante 14 días en 18 preescolares, asistentes a guarderías infantiles. La ingesta energética se determinó mediante un método combinado: pesaje de alimentos durante los días de la semana y registro después de salir del centro (17 horas en adelante), además de un recordatorio de 24 horas, durante un día del fin de semana. Resultados: el promedio individual del gasto energético total fue 1373 ± 177 kcal y la ingesta de energía (1409 ± 161 kcal). La diferencia global entre la ingesta y el gasto fue 42,9 kcal/día. El error de medición del GET explicó una variación del 2,4%, entre ambas mediciones, y el espacio de dilución de isótopos fue 1030 ± 0.010, confirmando el valor utilizado en los estudios de adultos. Conclusiones: los datos de GET fueron similares a otros estudios realizados en niños en edad preescolar. La pequeña diferencia encontrada entre la ingesta y el gasto energético se puede atribuir a la metodología de la ingesta de energía aplicada, la dieta homogénea en los centros de atención, durante los días de la semana, y el bajo error metodológico del ADM.

Pilot nutrition and physical activity intervention for preschool children attending daycare centres (JUNJI): primary and secondary outcomes.

INTRODUCTION: A pilot intervention was conducted to promote physical activity and nutrition in public preschool education (near half a million children in Chile), in order to prevent obesity. OBJECTIVE: To assess the primary (body fat) and secondary outcomes (physical activity and energy intake) of a nutrition and physical activity pilot intervention for preschool children, attending day care centres. METHODS: A pilot intervention in six day care centres selected at random (n = 530), in 4-5 years old preschool children, Santiago, Chile intending to: provide nutritional and physical activity education to educators and health promotion activities for the family, which in turn, will affect the primary (body fat), and secondary outcomes (physical activity pattern and energy food intake) were measured in a representative subsample of 120 intervened and 145 controls children. RESULTS: In relation to secondary outcomes monitoring, moderate-vigorous activity was duplicated in the intervention group (+5.4% and +4.7%, respectively), in both obese and eutrophic children. Energy intake decreased in 11.7% in obese and 7.5% in eutrophic children. Dietary fat intake was reduced (-11 g in obese and -8.4 g in eutrophic children). Intervened obese children reduced body fat in 1.5%, meanwhile in control obese children, body fat increased 1.3% (p < 0.01). CONCLUSIONS: The pilot intervention demonstrated the feasibility to influence dietary risk factors and physical activity at the day care centres and families. Therefore, the implementation of the validated intervention program will be tested in different weather conditions, to prevent unhealthy habits in preschool children and their families.

Introducción: Intervención piloto en nutrición y actividad física para prevenir obesidad en la educación preescolar (cerca de medio millón de niños en Chile). Objetivo: Evaluar los resultados primarios (grasa corporal) y secundarios (actividad física e ingesta energética) de una intervención piloto para niños/as asistentes a guarderías infantiles. Métodos: Intervención piloto en seis guarderías seleccionadas al azar (n = 530 preescolares), 4-5 años en Santiago de Chile, con el objeto de: a) proporcionar educación en nutrición y actividad física para los educadores; b) actividades de promoción de la salud para la familia. El objetivo primario (grasa corporal), y los resultados secundarios (patrón de actividad física y la ingesta energética) se midieron en 265 preescolares (120 intervenidos y 145 niños controles). Resultados: La actividad física moderada- intensa se duplicó en los intervenidos (+5,4% y +4,7%, respectivamente), tanto en niños obesos y eutróficos. La ingesta energética se redujo en 11,7% en obesos y 7,5% en los eutróficos y la de grasa en (-11 g en obesos y -8,4 g en niños eutróficos). Los niños obesos intervenidos redujeron la grasa corporal en 1,5%, mientras que en los niños controles obesos, se incrementó 1,3% (p < 0,01). Conclusiones: La intervención piloto demostró la viabilidad de influir en los factores de riesgo dietarios y de actividad física en las guarderías y en las familias. Por lo tanto, la ejecución del proyecto piloto se pondrá a prueba en diferentes condiciones climáticas, para prevenir hábitos no saludables en los preescolares y sus familias.

Pilot nutrition and physical activity intervention for preschool children attending daycare centres (JUNJI); primary and secondary outcomes / Intervención piloto en nutrición y actividad física para preescolares asistentes a jardines infantiles (JUNJI); resultados primarios y secundarios

Introduction: A pilot intervention was conducted to promote physical activity and nutrition in public preschool education (near half a million children in Chile), in order to prevent obesity. Objective: To assess the primary (body fat) and secondary outcomes (physical activity and energy intake) of a nutrition and physical activity pilot intervention for preschool children, attending day care centres. Methods: A pilot intervention in six day care centres selected at random (n = 530), in 4-5 years old preschool children, Santiago, Chile intending to: provide nutritional and physical activity education to educators and health promotion activities for the family, which in turn, will affect the primary (body fat), and secondary outcomes (physical activity pattern and energy food intake) were measured in a representative subsample of 120 intervened and 145 controls children. Results: In relation to secondary outcomes monitoring, moderate-vigorous activity was duplicated in the intervention group (+5.4% and +4.7%, respectively), in both obese and eutrophic children. Energy intake decreased in 11.7% in obese and 7.5% in eutrophic children. Dietary fat intake was reduced (-11 g in obese and -8.4 g in eutrophic children). Intervened obese children reduced body fat in 1.5%, meanwhile in control obese children, body fat increased 1.3% (p < 0.01). Conclusions: The pilot intervention demonstrated the feasibility to influence dietary risk factors and physical activity at the day care centres and families. Therefore, the implementation of the validated intervention program will be tested in different weather conditions, to prevent unhealthy habits in preschool children and their families (AU)

Introducción: Intervención piloto en nutrición y actividad física para prevenir obesidad en la educación preescolar (cerca de medio millón de niños en Chile). Objetivo: Evaluar los resultados primarios (grasa corporal) y secundarios (actividad física e ingesta energética) de una intervención piloto para niños/as asistentes a guarderías infantiles. Métodos: Intervención piloto en seis guarderías seleccionadas al azar (n = 530 preescolares), 4-5 años en Santiago de Chile, con el objeto de: a) proporcionar educación en nutrición y actividad física para los educadores; b) actividades de promoción de la salud para la familia. El objetivo primario (grasa corporal), y los resultados secundarios (patrón de actividad física y la ingesta energética) se midieron en 265 preescolares (120 intervenidos y 145 niños controles). Resultados: La actividad física moderada- intensa se duplicó en los intervenidos (+5,4% y +4,7%, respectivamente), tanto en niños obesos y eutróficos. La ingesta energética se redujo en 11,7% en obesos y 7,5% en los eutróficos y la de grasa en (-11 g en obesos y -8,4 g en niños eutróficos). Los niños obesos intervenidos redujeron la grasa corporal en 1,5%, mientras que en los niños controles obesos, se incrementó 1,3% (p < 0,01). Conclusiones: La intervención piloto demostró la viabilidad de influir en los factores de riesgo dietarios y de actividad física en las guarderías y en las familias. Por lo tanto, la ejecución del proyecto piloto se pondrá a prueba en diferentes condiciones climáticas, para prevenir hábitos no saludables en los preescolares y sus familias (AU)

[Impact of strength training exercise on secondary prevention of childhood obesity; an intervention within the school system]. / Impacto del ejercicio de fuerza muscular en la prevención secundaria de la obesidad infantil; intervención al interior del sistema escolar.

INTRODUCTION: The physical exercise is an important therapeutic tool to prevent and treat obesity, as well as reducing metabolic alterations and the risk of non-communicable diseases. OBJECTIVE: To evaluate the impact of a strength training exercise intervention within the school system, this includes muscular strength exercise, dietary education and psychological support in obese children. METHODS: We worked with 120 obese schoolchildren, between 8 and 13 years, recruited from 3 schools. Group 1 (n = 60) participated in the intervention, which included physical exercise, dietary education, and psychological support, for 3 months. Group 2 (n = 60) received only the educational intervention and psychological support for the first 3 months, and then received the exercise intervention from months 3 to 6. Participants were evaluated for BMI, waist circumference, body fat, presence of metabolic syndrome and cardiovascular risk factors. RESULTS: At 3 months, there were significant differences between the groups for change in BMI z-score, waist circumference, and body fat as well as prevalence of metabolic syndrome, abdominal obesity, hypertriglyceridemia, and fasting hyperglycemia. In group 1, these parameters decreased and increased, in group 2. From months 3 to 6, Group 2 showed a significant decrease in abdominal obesity, high blood pressure, and hypertriglyceridemia, while Group 1 showed a significant increase in high blood pressure and no change in other cardiovascular risk factors. CONCLUSION: This study demonstrates the positive impact of a strength training physical exercise program on reduction of body fat, metabolic syndrome and cardiovascular risk factors. This study supports the use of exercise as a treatment for obesity and its comorbidities in schoolchildren.

Introducción: El ejercicio físico es una importante herramienta terapéutica para prevenir y tratar la obesidad y disminuir las alteraciones metabólicas asociadas al desarrollo de las enfermedades crónicas no transmisibles. Objetivo: Evaluar el impacto de una intervención al interior del sistema escolar, que incluye el ejercicio de fuerza muscular, educación alimentaria y apoyo psicológico en escolares obesos. Métodos: Se trabajó con 120 escolares obesos, entre 8 y 13 AÑOs, reclutados en 3 colegios. El Grupo 1 (n = 60), fueron intervenidos simultáneamente con ejercicio físico, educación alimentaria y apoyo psicológico durante 3 meses. El Grupo 2 (n = 60), durante el mismo período, recibió sólo la intervención educativa y el apoyo psicológico, siendo intervenido con ejercicio entre los 3 y los 6 meses. Se evaluó IMC, perímetro de cintura, grasa corporal, síndrome metabólico y factores de riesgo cardiovasculares. Resultados: A los 3 meses, hubo diferencias significativas entre ambos grupos en la variación del zIMC, circunferencia cintura, grasa corporal, síndrome metabólico, obesidad abdominal, hipertrigliceridemia e hiperglicemia de ayuno. En el grupo 1, estos parámetros disminuyeron y aumentaron, en el grupo 2. Entre los 3-6 meses, en el grupo 2, hubo una disminución significativa en la obesidad abdominal, presión arterial elevada e hipertrigliceridemia, en tanto en el grupo 1, aumento significativo de la presión arterial elevada sin variaciones en los otros factores de riesgo cardiovasculares. Conclusiones: Se demostró el impacto positivo del ejercicio físico de fuerza muscular en la reducción de la grasa corporal, del síndrome metabólico y de los factores de riesgo cardiovasculares. Este trabajo refuerza el uso del ejercicio como tratamiento de la obesidad y de sus comorbilidades en escolares.