Luciano Machado Ferreira Tenório de Oliveira

Intra-individuals and inter- and intra-observer reliability of short-term heart rate variability in adolescents

To examine the reliability of heart rate variability (HRV) parameters in adolescents and to analyse the inter‐ and intra‐observer reliability of data analysis.

Association between general and abdominal obesity with high blood pressure: difference between genders

OBJECTIVE To assess the association between general and abdominal obesity with high blood pressure in adolescents of both genders from the public school system. METHODS This was an epidemiological, descriptive, exploratory study, with a quantitative approach and local scope whose sample consisted of 481 high school students (aged 14-19), selected by using a random cluster sampling strategy. Blood pressure was measured through the use of automated monitor and was considered high when the pressure values were at or above the 95th percentile. The analyses were performed using the chi-squared test and binary logistic regression. RESULTS The prevalence of high blood pressure was 6.4%, and it was higher among boys (9.0% vs. 4.7%, p<0.05). There was no significant difference between general (p=0.903) and abdominal obesity (p=0.157) when genders were compared. After adjusting for age, high blood pressure was associated with general (OR=6.4; p<0.001) and abdominal obesity (OR=7.0; p<0.001) only among boys, when comparing the fourth quartile with the first quartile of body mass index (≤ 18.6 kg/m(2)vs. ≥ 23.5 kg/m(2)) and waist circumference (≤ 69 cm vs. ≥ 80.1cm). CONCLUSION It was observed that general and abdominal obesity are associated with high blood pressure only in boys, regardless of age.

EXERCÍCIO FÍSICO OU ATIVIDADE FÍSICA: QUAL APRESENTA MAIOR ASSOCIAÇÃO COM A PERCEPÇÃO DA QUALIDADE DO SONO DE ADOLESCENTES?

ABSTRACT Objective: To analyze the association of exercises and physical activity with the perception of sleep quality by adolescents. Methods: This is a cross-sectional epidemiological survey with statewide coverage, whose sample was composed of 6,261 adolescents (14-19 years old) who were selected by random sampling of conglomerates. The Global School-Based Student Health Survey questionnaire was used for data collection. The chi-square test and the binary logistic regression were applied for data analyses. Results: In the sample, 29% of adolescents did not exercise and were not classified as physically active. Adolescents who did not exercise were more likely to present a negative perception of sleep quality (OR 1.13, 95%CI 1.04-1.28, p=0.043). No association between the level of physical activity and the perception of sleep quality was found (OR 1.01, 95%CI 0.89-1.14, p=0.868). Those who practiced exercises only had less chance of perceiving sleep quality as poor (OR 0.82, 95%CI 0.71-0.95). However, those who practiced exercise and had a physically active life had less chances of having a negative perception of their sleep (OR 0.79, 95%CI 0.68-0.93). Conclusions: Practicing physical activity alone was not enough to increase the chances of positive sleep quality perception. Only physical exercise had a positive association with sleep quality perception.

Health self-perception and its association with physical activity and nutritional status in adolescents

OBJECTIVE To evaluate the association between total physical activities, physical activity in free time and nutritional status with self-perceived health in adolescents of both genders. METHODS This is a quantitative study that integrates the school-based, cross-sectional epidemiological survey with statewide coverage, whose sample consisted of 6261 adolescents (14-19 years old) selected by random conglomerate sampling. Data were collected using the Global School-based Student Health Survey. The chi-squared test (χ2) and the Poisson regression model with robust variance were used in the data analyses. RESULTS It was observed that 27.3% of the adolescents had a negative health self-perception, which was higher among girls (33.0% vs. 19.0%, p<0.001). After adjusting for potential confounding factors, it was observed that boys who did not practice physical activity during free time (PR=1.44, 95% CI: 1.15-1.81) and were classified as insufficiently active (PR=1.27, 95% CI: 1.04-1.56), as well as girls who did not practice physical activity during free time (PR=1.15, 95% CI: 1.02-1.29) and were classified as overweight (PR=1.27, 95% CI: 1.01-1.29) had a greater chance of negative health self-perception. CONCLUSION Behavioral issues may have different effects on health self-perception when comparing boys with girls. Negative health self-perception was associated with nutritional status in girls and a lower level of physical activity in boys, and the practice of physical activity in the free time was considered a protective factor against a negative health self-perception for adolescents of both genders.

Does the type of sedentary behaviors influence blood pressurein adolescents boys and girls? A cross-sectional study

The aim of this study was to analyze the association between different sedentary behaviors and high blood pressure in adolescent boys and girls. We conducted a cross-sectional study with 6,264 Brazilian adolescents (14 to 19 years old). Demographic data, obesity indicators and blood pressure, were evaluated. Time spent in the sedentary behaviors (television viewing, playing video games, using the computer, non-screen sitting and, total time sitting) were also assessed. The girls spent more time watching television than boys, whereas boys spent more time using computers and video games (12.7% vs. 7.4%, p < 0.001) than girls. Boys who watched more than four hours of television presented higher odds to give high blood pressure after adjustments for physical activity level, body mass index, age and educational level of mother (OR = 2.27, p < 0.001). In girls, we did not find a relation between sedentary behaviors and high blood pressure (p > 0.05). Television viewing time is associated with high blood pressure only boys. So, reduce this sedentary behavior, stimulating physical activities, might be essential to health, principally for male adolescents.