BackgroundIn adults, there is a substantial body of evidence that physical inactivity or low cardiorespiratory fitness levels are strongly associated with the development of metabolic syndrome. Although this association has been studied extensively in adults, little is known regarding this association in adolescents. The aim of this study was to analyze the association between physical activity and cardiorespiratory fitness levels with metabolic syndrome in Brazilian adolescents.MethodsA random sample of 223 girls (mean age, 14.4 ± 1.6 years) and 233 boys (mean age, 14.6 ± 1.6 years) was selected for the study. The level of physical activity was determined by the Bouchard three-day physical activity record. Cardiorespiratory fitness was estimated by the Leger 20-meter shuttle run test. The metabolic syndrome components assessed included waist circumference, blood pressure, HDL-cholesterol, triglycerides, and fasting plasma glucose levels. Independent Student t-tests were used to assess gender differences. The associations between physical activity and cardiorespiratory fitness with the presence of metabolic syndrome were calculated using logistic regression models adjusted for age and gender.ResultsA high prevalence of metabolic syndrome was observed in inactive adolescents (males, 11.4%; females, 7.2%) and adolescents with low cardiorespiratory fitness levels (males, 13.9%; females, 8.6%). A significant relationship existed between metabolic syndrome and low cardiorespiratory fitness (OR, 3.0 [1.13-7.94]).ConclusionThe prevalence of metabolic syndrome is high among adolescents who are inactive and those with low cardiorespiratory fitness. Prevention strategies for metabolic syndrome should concentrate on enhancing fitness levels early in life.

Objective:To analyze physical activity and sedentary behavior in preschool children during their stay at school and the associated factors.Methods:370 preschoolers, aged 4–6 years, stratified according to gender, age and school region in the city of Londrina, PR, participated in the study. A questionnaire was applied to principals of preschools to analyze the school infrastructure and environment. Physical activity and sedentary behavior were estimated using accelerometers for five consecutive days during the children's stay at school. The odds ratio (OR) was estimated through binary logistic regression.Results:At school, regardless of age, preschoolers spend relatively more time in sedentary behaviors (89.6–90.9%), followed by light (4.6–7.6%), moderate (1.3–3.0%) and vigorous (0.5–2.3%) physical activity. The indoor recreation room (OR 0.20, 95%CI 0.05–0.83) and the playground (OR 0.08, 95%CI 0.00–0.80) protect four-year-old schoolchildren from highly sedentary behavior. An inverse association was found between the indoor recreation room and physical activity (OR 0.20, 95%CI 0.00–0.93) in five-year-old children. The indoor recreation room (OR 1.54, 95%CI 1.35–1.77), the playground (OR 2.82, 95%CI 1.14–6.96) and the recess (OR 1.54, 95%CI 1.35–1.77) are factors that increase the chance of six-year-old schoolchildren to be active.Conclusions:The school infrastructure and environment should be seen as strategies to promote physical activity and reduce sedentary behavior in preschool children.

BackgroundArterial hypertension is a major public health problem and has increased considerably in young individuals in past years. Thus, identifying factors associated with this condition is important to guide intervention strategies in this population.ObjectiveTo determine high blood pressure prevalence and its associated factors in adolescents.MethodsA random sample of 1,242 students enrolled in public schools of the city of Curitiba (PR) was selected. Self-administered questionnaires provided family history of hypertension, daily energy expenditure, smoking habit, daily fat intake, and socioeconomic status. Waist circumference was measured following standardized procedures, and blood pressure was measured with appropriate cuffs in 2 consecutive days to confirm high blood pressure. Relative frequency and confidence interval (95%CI) indicated high blood pressure prevalence. Bivariate and multivariate analyses assessed the association of risk factors with high blood pressure.ResultsThe high blood pressure prevalence was 18.2% (95%CI 15.2-21.6). Individuals whose both parents had hypertension [odds ratio (OR), 2.22; 95%CI 1.28-3.85] and those with high waist circumference (OR, 2.1; 95%CI 1.34-3.28) had higher chances to develop high blood pressure.ConclusionPositive family history of hypertension and high waist circumference were associated with high blood pressure in adolescents. These factors are important to guide future interventions in this population.

The purpose of the study was to examine the minimum number of monitoring days for reliably estimating physical activity (PA) and sedentary behaviour (SB) from accelerometer data in older adults. Forty-two older adults from a local senior centre participated in this study. Participants wore an ActiGraph wGT3X-BT on the right hip for 7 consecutive days. Accelerometer data were downloaded to a computer and converted to activity count data in 60s epochs. Time spent in SB and different PA intensity categories were estimated with commonly used activity count cut-points. Participants with at least 7 valid days of monitoring (≥10 hday) were included in the analysis. Intraclass correlation coefficients (ICC) were calculated for determining single-day monitoring reliability. The Spearman-Brown prophecy formula was used to estimate the minimum number of monitoring days required for achieving an ICC of 0.80. Single-day ICC values for time spent in SB and PA intensity categories ranged from 0.45 to 0.61. Minimum number of monitoring days required for achieving an ICC of 0.80 ranged from 2.5 to 4.9 days. In this study, a minimum of 5 consecutive days of monitoring was required for reliably estimating SB and PA from accelerometer data in older adults.

Objectives: to characterize the nutritional status a n d d i e t a r y Organization. Dietary intake was calculated using the S u r v e y o f C o n s u m e r F o o d F re q u e n c y. A n a l y s i s w a s carried out using descriptive and frequency analysis, and Student's t test with p<0.05. R e s u l t s : m o s t i n d i v i d u a l s p re s e n t e d a n o r m a l n u t r i t i o n a l s t a t u s ( 8 4 % b e i n g e u t ro p h i c , 1 2 % o v e rw e i g h t / o b e s e a n d 4 % u n d e r w e i g h t ) . T h e d i e t w a s

The school infrastructure and environment should be seen as strategies to promote physical activity and reduce sedentary behavior in preschool children.

BackgroundThe clustering of metabolic syndrome risk factors is inversely related to the amount of physical activity. However, the question remains as to how much daily physical activity is enough to prevent the onset of metabolic disorders in adolescents? Therefore, the objectives of this study were to associate the metabolic risk score with the moderate to vigorous physical activity (MVPA) and to identify the amount of daily physical activity to prevent the onset of the metabolic risk factors in Brazilian adolescents.MethodsThe study involved 391 participants aged 10 to 18 years. Physical activity was measured by accelerometry. The counts obtained in the different activities were transformed into metabolic equivalents and classified as light (≥ 1.5 but < 3.0 METs), moderate (≥ 3.0 but < 6.0 METs) and vigorous (≥ 6.0 METs) activities. The continuous risk score for metabolic syndrome was calculated using the following risk factors: waist circumference, blood pressure, blood glucose, HDL-C and triglycerides.ResultsTime spent in MVPA was inversely associated with the continuous risk score for metabolic syndrome (p < 0.05). Analysis of the ROC curve suggests that these adolescents must perform at least 88 minutes per day of MVPA.ConclusionsThese findings reinforce previous evidence that physical activity relates to metabolic syndrome in adolescents. This population should be encouraged to gradually replace part of their sedentary time with physical activities.

Artículo recibido el 10/03/09; revisado recibido el 16/06/09; aceptado el 24/09/09. ResumenFundamento: La aterosclerosis es la enfermedad coronaria que afecta con mayor frecuencia a la población adulta brasilera. Aún cuando se trata de una enfermedad predominantemente de adultos, los factores de riesgo asociados pueden surgir en individuos jóvenes.Objetivo: Verificar la asociación del nivel de actividad física (NAF) y el consumo de lípidos con los factores de riesgo para aterosclerosis en adolescentes.Métodos: Fueron evaluados 260 niños y 237 niñas con edades entre 10 y 18 años. El nivel de actividad física fue estimado a través del recordatorio propuesto por Bouchard et al. El consumo de lípidos fue evaluado mediante una encuesta alimentaria desarrollada por Sichieri y Everhart. La presión arterial se midió utilizando un esfigmomanómetro de columna de mercurio. El colesterol total, el HDL-C y los triglicéridos fueron determinados por el método enzimático-colorimétrico. El LDL-C se calculó mediante la fórmula de Friedewald. En el análisis estadístico, se empleó la regresión logística, con nivel de significancia estipulado en p < 0,05.Resultados: En cuanto al NAF, el 17,3% de los niños y el 22,6% de las niñas fueron clasificados como sedentarios. En los hábitos alimentarios, el 54% y el 48,6% de los niños y niñas, respectivamente, presentaron consumo de lípidos por encima de las recomendaciones. Niños con niveles elevados de colesterol total y de LDL-C tuvieron mayor razón de chances de ser sedentarios que sus pares más activos. La aparición de niveles elevados de LDL-C estuvo asociada al consumo excesivo de grasa saturada en ambos sexos. a una menor predisposición a los factores de riesgo para enfermedades cardiovasculares en adultos 2,4 . Sin embargo, no todos estos resultados hallados fueron confirmados en poblaciones pediátricas [5][6][7] . Estudios de prevalencia recientes han demostrado que la exposición a los factores de riesgo para aterosclerosis no se restringe a la población adulta 8,9 , contrariando, de esta forma, la creencia generalizada de que niños y adolescentes están al margen de este tipo de riesgo para la salud. ConclusiónCon datos del Bogalusa Heart Study, Berenson et al 10 demostraron la presencia de factores de riesgo, como el aumento del índice de masa corporal, presión arterial, LDL-C y triglicéridos y relataron que estos aumentos están relacionados a lesiones ateroscleróticas, aún en individuos jóvenes.Salvo en trastornos congénitos, en los que los cambios de conducta pueden no ser suficientes para la normalización metabólica de los portadores, algunos factores de riesgo son receptivos a cambios comportamentales 11 . Así, estos cambios IntroducciónLa aterosclerosis es la enfermedad coronaria que afecta con mayor frecuencia a la población adulta brasilera, y la hipertensión arterial y las dislipidemias son los principales factores de riesgo para su desarrollo 1 . Estudios publicados refieren que, independientemente del origen étnico, individuos que consumen grandes cantidades de grasas, pr...