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Aim: To investigate the association of parental and adolescents' screen time with self-rated health and to examine the mediating effects of psychosocial factors (social relationships and distress) on this association. Method: A cross-sectional study was conducted among 984 Brazilian adolescents (10- to 17-year-olds). Self-rated health, screen time (adolescents and parental), and perception of social relationships and distress were evaluated through self-report questionnaires. Structural equation modeling was adopted to investigate the pathways of the relationship between adolescents' screen time and self-rated health. Results: Adolescents' screen time was directly and negatively related to self-rated health only in boys (r = -0.158, p = 0.015). In girls, screen time was related to self-rated health through distress (r = -0.188, p = 0.007) and social relationships (r = 0.176, p = 0.008). The models fit was adequate (?[superscript 2]/df = 3.0, root mean square error of approximation <0.08, comparative fit index >0.90, and Tucker-Lewis Index >0.90). Conclusions: Higher screen time was associated with poor self-rated health in boys, while in girls, psychosocial factors mediated the adverse relationships between screen time and self-rated health.

The purpose of the study was to clarify the independent association between sedentary behavior and physical activity with multiple chronic diseases and medicine intake in older individuals. Sedentary behavior and physical activity were measured by questionnaires. Diseases and medication use were self-reported. Poisson's regression was adopted for main analysis, through crude and adjusted prevalence ratio and confidence interval of 95%. For men, sedentary time >4 hr/day presented a 76% higher prevalence of ≥2 chronic diseases, while physical inactivity increases the likelihood of using ≥2 medicines in 95%. For women, sedentary behavior >4 hr/day presented an 82% and 43% greater prevalence for ≥2 chronic diseases and the intake of ≥2 medicines, respectively. Sedentary behavior represents an independent associated factor of multiple chronic diseases in older men and women. In addition, inactivity for men and sedentarism for women are associated with the amount of medicine intake. [ABSTRACT FROM AUTHOR]

Background: This study describes the levels and patterns of television (TV) viewing in Brazilian adults and investigates associations of TV viewing with hypertension, type 2 diabetes, and heart disease. Methods: Data from the Brazilian Health Survey, a nationally representative survey that was conducted in 2013 (N = 60,202 men and women age≥ =18 y), were used. Information regarding TV viewing, physician diagnoses of type 2 diabetes, hypertension, and heart disease was collected via interview-administered questionnaire. Data on covariables (including chronological age, educational status, skin color, sodium consumption, sugar consumption, tobacco smoking, alcohol consumption, and leisure-time physical activity) were also selfreported. Logistic regression models and population attributable fractions were used for the etiological analyses. Results: The prevalence (95% confidence interval) of >4 hours per day of TV viewing was 12.7% (12.0-13.4) in men and 17.5% (16.8-18.3) in women. Men and women being younger or older, moderately educated, living alone, smoking tobacco, and drinking alcohol were associated with higher reported TV viewing time. Odds ratios (95% confidence interval) revealed that >4 hours per day of TV viewing was associated with type 2 diabetes [male: 1.64 (1.23-2.17) and female: 1.33 (1.09-1.63)], hypertension [male: 1.36 (1.14-1.63) and female: 1.20 (1.05-1.37)], and heart disease [male: 1.96 (1.43-2.69) and female: 1.30 (1.00-1.68)]. Exceeding 4 hours per day of TV viewing was responsible for 6.8% of type 2 diabetes, 3.7% of hypertension, and 7.5% of heart disease cases. Conclusions: Independent of covariates, >4 hours per day of TV viewing was associated with type 2 diabetes, hypertension, and heart disease. High volumes of TV viewing are prevalent and appear to contribute to chronic disease burden. [ABSTRACT FROM AUTHOR]

Background This study examined the joint associations of leisure time physical activity and television (TV) viewing time with the prevalence of chronic diseases among Brazilian adults. Methods Data from the Brazilian Health Survey, a nationally representative survey conducted in 2013 (n  = 60 202; ≥18 years), were used. Time spent in TV viewing and leisure physical activity, physician diagnoses of diabetes, hypertension and heart disease and information on co-variables (chronological age, education, ethnicity, candies/sweets consumption, sodium intake and tobacco smoking) were collected via interview. Descriptive statistics (mean and 95% confidence interval) and logistic regression models were used for etiological analyses. Results Physical activity attenuated but did not eliminate the risk associated with high TV viewing for at least one chronic disease in the general population [odds ratio [OR]: 1.29 (1.11–1.50)] and among women [OR: 1.31 (1.09–1.60)], adults [OR: 1.24 (1.05–1.46)] and older adults [OR: 1.63 (1.05–2.53)]. On the other hand, physical activity eliminated the risk associated with high TV viewing for at least one chronic disease among men [OR: 1.24 (0.98–1.58)]. Conclusions We conclude that physical activity can attenuate but not eliminate the negative effects of high TV viewing on chronic disease among subgroups of Brazilian adults. [ABSTRACT FROM AUTHOR]

Background and purpose: There is a growing body of evidence indicating that phase angle (PhA) can be used as an indicator of nutritional status, disease prognosis, and mortality risk; however, it is still unknown whether PhA can be used as an explanator of functional capacity and muscle quality in older women. The main purpose of this cross-sectional study was to explore whether PhA is associated with muscle quality and functional capacity in older women, regardless of total and regional body composition. Methods: A total of 125 older women-66.7 (4.7) years; 65.6 (10.9) kg body mass; 156.1 (5.2) cm height; 26.9 (4.0) kg/m body mass index-participated in this study. Anthropometric, PhA, body composition (whole-body dual-energy x-ray absorptiometry) and muscle quality (defined as total muscular strength per kilogram of appendicular lean soft tissue) were measured. The functional capacity was assessed by 4 tests: 10-m walk test, rising from sitting position, rising from ventral decubitus position, and rising from a chair and walking around the house. The summing z-scores for the 4 tests was used as a continuous functional capacity score. Linear regression analysis was conducted to test whether PhA is related to the dependent variables (muscle quality and functional capacity), after adjusting for potential covariates. Results: The PhA presented a small-to-moderate relationship with muscle quality (r = 0.27; P < .01) and functional capacity (r = 0.31; P < .01), respectively. These relationships remained significant after adjustment for age, lower limb lean soft tissue, and total fat mass for muscle quality (β= 0.55; P < .01) and functional capacity (β= 1.38; P < .01). Conclusion: Our findings suggest that healthy elderly women with higher values of PhA have a better muscle quality and functionality, regardless of age and body composition. [ABSTRACT FROM AUTHOR]

Aim Examine the association between child and adolescent physical activity maintenance categories and metabolic profile in adolescence. Methods This cross-sectional study was conducted with 1152 adolescents (57.4% female) aged 10–16 years from Londrina, Brazil. Physical activity was self-reported in childhood (7–10 years old, retrospective data) and adolescence through questionnaires. Cardiorespiratory fitness (20 m shuttle-run test), body fat (skinfolds), waist circumference, blood pressure (automatic instrument) and blood variables (fasting glucose, HDL-cholesterol and triglycerides) were measured at adolescence. Results Frequency of physical activity in childhood and adolescence was 50.3 and 17.2%, respectively, and only 25.7% of boys and 10.9% of girls were active at both ages. Adolescents who were physically active in childhood alone were less likely [OR = 0.71 (95% CI: 0.52–0.97)] to present low cardiorespiratory fitness in adolescence compared to those who were non-active in childhood. Regardless of controlled, actives in childhood and adolescence were less likely to present low cardiorespiratory fitness [OR = 0.50 (95% CI: 0.34–0.73)], high blood pressure [OR = 0.52 (95% CI: 0.32–0.85)] and high metabolic risk score [OR = 0.44 (95% CI: 0.22–0.90)] compared to the non-actives at both ages. Conclusions Actives through childhood to adolescence are less likely to present low cardiorespiratory fitness, high blood pressure and high metabolic risk. [ABSTRACT FROM AUTHOR]

The aim of this study was to estimate the prevalence and correlates of blood pressure (BP) according to somatic maturation in Southern Brazilian adolescents. A total of 1321 adolescents participated in the study (732 girls), aged between 10 and 16 years, enrolled in public schools. The assessment of BP was performed using oscillometric equipment. Measurements of body weight, height, waist circumference, and skinfold thickness were performed. Somatic maturation was estimated by the age at peak height velocity. Behavioral and hereditary variables were obtained using a questionnaire. Early-maturing adolescents had the highest prevalence of high BP (28%; 95% confidence interval, 24.6-33.5) compared with other maturational groups (P=.003). In late-maturing adolescents, the variables associated with BP were paternal hypertension (systolic BP: β=4.9; diastolic BP: β=5.3) and early physical activity (systolic BP: β=-4.0; diastolic DBP: β=-3.6). In average-maturing adolescents, waist circumference (systolic BP: β=0.3), body mass index (diastolic BP: β=0.5), and mother's hypertension (diastolic BP: β=1.8) were positively related to BP. In early-maturing adolescents, only waist circumference (systolic BP: β=0.3; diastolic BP: β=0.3) was associated with BP. The authors conclude that the prevalence of high BP is greater in adolescents with early maturity and the outcome appears to be related to biological indicators in this group. On the other hand, in late-maturing adolescents, behavioral and hereditary variables are more related to BP. [ABSTRACT FROM AUTHOR]

Objectives To analyze the relationship between different physical activity (PA) domains and sociodemographic, psychological, behavioral and biological factors in Brazilian adolescents. Methods 1,220 adolescents (55.1% female) aged between 10 and 16 years-old participated in this study. The Baecke questionnaire was used to evaluate different PA domains, namely occupational, sports and leisure-time. Socioeconomic status, number of siblings, friendships satisfaction, mother's and father's PA level and previous experience with sports were self-reported. Cardiorespiratory fitness, waist circumference, and somatic maturity were estimated by objective indicators. Linear regression was used for the main statistical analysis. Results The variables consistently related to all of the PA domains were gender (boys more active), friendship satisfaction (positive with sports and leisure-time PA and negative with occupational PA) and cardiorespiratory fitness (positive). There were also domain-specific relationships for occupational (number of siblings [ β = 0.02] and father's PA [ β = 0.13]), sport practice (previous experience with sports [ β = 0.33], waist circumference [ β = 0.01] and somatic maturity [ β = −0.12]) and leisure-time PA (chronological age [ β = −0.15], mother's PA [ β = 0.47] and previous experience with sports [ β = 0.17]). Conclusions The different domains of PA are related to specific variables in adolescence. This information may be helpful in formulating strategies for physical activity promotion, particularly in adolescents from low-to-middle income countries. Am. J. Hum. Biol. 28:112-117, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

The article reports on research which investigated the effects static stretching had on the performance of multiple sets in the bench press (BP) exercise. Researchers evaluated 15 men who performed the bench press and either stretched or did not. They found that the performance of multiple sets in the BP exercise did not seem to be influenced by static stretching.

The article presents the results of a study which investigated the effect of exercise intensity upon perceived exertion during multi-set resistance training. An overview of related previous research is provided, detailing a drop in the intensity between sets is required to maintain the same level of perceived exertion. Details of the experiment protocol are also presented, including use interval 1-repetition maximum test sessions and the OMNI Resistance Exercise Scale.

Purpose: In postmenopausal women, optimizing muscular strength and physical performance through proper resistance training (RT) is crucial in achieving optimal functional reserve later in life. This study aimed to compare if a higher-load-tolower-load (HL-to-LL) scheme is more effective than a lower-load-to-higher-load (LL-to-HL) scheme on muscular strength and physical performance in postmenopausal women after 12 and 24 wk of RT. Methods: Twenty-four postmenopausal women were randomized into two groups: LL-to-HL (n = 12, 27-31 repetitions maximum (RM) in the first 12 wk, and 8-12RM in the last 12 wk) or HL-to-LL (n = 12, 8-12RM during the first 12 wk, and 27-31RM in the last 12 wk). Muscular dynamic (1RM test) and isometric strength (MIVC) and functional tests (sit-to-stand power, 400-m walking, and 6-min walking) were analyzed at baseline, after 12 and 24 wk. Results: Different load intensity transition schemes resulted in enhancements (P < 0.05) in dynamic (45° leg press: LL-to-HL = 21.98% vs HL-to-LL = 16.07%; leg extension: LL-to-HL = 23.25% vs HL-to-LL = 16.28%; leg curl: LL-to-HL = 23.89% vs HL-to-LL = 13.34%) and isometric strength (LLto-HL = 14.63% vs HL-to-LL = 19.42%), sit-to-stand power (LL-to-HL = 7.32% vs HL-to-LL = 0%), and walking speed (400-m test: LL-to-HL = 3.30%vsHL-to-LL = 5.52%; 6-min test: LL-to-HL = 4.44%vs HL-to-LL = 5.55%) after 24wk of RT, without differences between groups (P > 0.05). However, only the HL increased the dynamic strength in 45° leg press and leg extension and sit-to-stand power. Moreover, walking speed changes were more strongly correlated with the changes in MIVC (P < 0.05). Conclusions: Our results indicate that both load intensity transition schemes produce similar improvements in muscular strength and physical performance in postmenopausal women after 24 wk of RT. However, the HL was more effective in increasing 45° leg press and leg extension strength, as well as power (mainly when performed after the LL), whereas having little effect on leg curl strength, isometric strength, and walking speed. Our findings suggest that although an HL makes a muscle isotonically stronger, it may have limited impact on isometric strength and walking speed in postmenopausal women. [ABSTRACT FROM AUTHOR]

Background: Aging is accompanied by progressive and accentuated decline in muscular strength and skeletal muscle mass, affecting health and functional autonomy. Both resistance training (RT) and diet are strategies that may contribute to improvement in the health of the elderly., Aim: The purpose of this study was to evaluate the effects of higher habitual protein intake on RT-induced changes in body composition and strength in untrained postmenopausal women., Methods: Seventy older women were submitted to an RT program. Body composition, muscular strength, and dietary intake (24 h dietary recall) were performed pre- and post-intervention. To verify different intervention effects according to protein intake of the participants, the sample was separated into tertiles according to protein intake: low, moderate, and high protein intake., Results: A time vs. group interaction ( p < 0.05) was observed, with high protein intake presenting greater increases compared with low protein intake, for skeletal muscle mass (5.3% vs. 1.3%), lower limb lean soft tissue (4.9% vs. 1.4%), upper lean soft tissue (4.9% vs. 1.2%), preacher curl (24% vs. 15.2%), and total strength (16.4% vs. 11.7%). A time vs. group interaction ( p < 0.05) was observed, with high protein intake presenting greater increases compared with moderate protein intake, for skeletal muscle mass (5.3% vs. 3.2%). In all groups, a main effect of time ( p < 0.05) was observed for knee extension and chest press., Conclusions: We conclude that intake of >1.0 g/kg/day of protein promotes gains in skeletal muscle mass and muscular strength after RT in untrained older women.

Objectives: The aim of the present study was to examine the stability of physical fitness, and the interrelationships among intra-individual changes in fitness and fatness among elementary school children., Methods: A longitudinal study was conducted among 372 adolescents (196 boys) and followed up over 3 years (from childhood to adolescence). Physical fitness was estimated using three indicators: cardiorespiratory fitness (through a 9-minute running test), flexibility (through a sit-and-reach test), and muscle resistance (through maximal abdominals in 1 minute). Body adiposity was obtained through triceps and subscapular skinfolds. Somatic maturation was assessed by the peak of height velocity. Kappa and Lin's tests of concordance as well as logistic regression analyses were conducted with P < 0.05 in STATA 15.1., Results: Tracking of physical fitness from childhood to adolescence was moderate for both sexes [boys: kappa = 0.441 (P < 0.001); LCCC = 0.591 (P < 0.001). Girls: kappa = 0.335 (P < 0.001); LCCC = 0.534 (P < 0.001)]. A larger increment in body fat was associated with a higher likelihood to decrease a tertile in physical fitness among boys [OR: 4.17 (95% CI: 1.31-13.22)] and with a lower likelihood to increase a tertile in physical fitness among both sexes [boys: OR = 0.25 (95% CI: 0.09-0.67); girls: OR: 0.37 (95% CI: 0.15-0.92)]., Conclusions: Health-related physical fitness has moderate tracking from childhood to adolescence. Increases in body adiposity from childhood to adolescence are associated with a reduction in physical fitness tertile., (© 2019 Wiley Periodicals, Inc.)

Objective: To test the biocultural model through direct and indirect associations between biological maturation, adiposity, cardiorespiratory fitness, feelings of sadness, social relationships, and physical activity in adolescents., Methods: This was a cross-sectional study conducted with 1,152 Brazilian adolescents aged between 10 and 17 years. Somatic maturation was estimated through Mirwald's method (peak height velocity). Physical activity was assessed through Baecke questionnaire (occupational, leisure, and sport contexts). Body mass index, body fat (sum of skinfolds), cardiorespiratory fitness (20-m shuttle run test), self-perceptions of social relationship, and frequency of sadness feelings were obtained for statistical modeling., Results: Somatic maturation is directly related to sport practice and leisure time physical activity only among girls (β=0.12, p<0.05 and β=0.09, respectively, p<0.05). Moreover, biological (adiposity and cardiorespiratory fitness), psychological (sadness), and social (satisfaction with social relationships) variables mediated the association between maturity and physical activity in boys and for occupational physical activity in girls. In general, models presented good fit coefficients., Conclusion: Biocultural model presents good fit and emotional/biological factors mediate part of the relationship between somatic maturation and physical activity., (Copyright © 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.)

Aim: The aim was to evaluate the association between age at menarche and cancer using a nationally representative sample of Brazilian women., Methods: Data from the Brazilian Health Survey (PNS), a nationally representative survey conducted in 2013 (n = 33,715 women; ≥18 years), were used. Information on cancer diagnosis, age at menarche and other co-variables (chronological age, educational status, skin colour, menopause, leisure-time physical activity and tobacco smoking) were collected via interview. Logistic regression models were used for aetiological analyses., Results: The prevalence of cancer diagnosis was greater among women with early age at menarche [2.6% (2.0-3.5%)] compared to on-time [1.6% (1.4-1.9%)] and late women [2.0% (1.1-3.4%)]. The onset of menarche ≤11 years was significantly associated with cancer risk, regardless of co-variables [OR =2.45 (1.34-4.48)], compared to the late group., Conclusion: Early age at menarche was associated with cancer risk in adulthood, regardless of race, educational status, chronological age, obesity, menopause onset, tobacco smoking or physical activity.

We examine the joint association of weight status and leisure-time physical activity on high blood pressure in a nationally representative sample of adults and older adults in Brazil. This was a national cross-sectional survey conducted in Brazil in 2013 (Brazilian Health Survey). The sample consisted of 59 402 participants (56% women, aged 18 to 100 years). Outcome was objectively assessed blood pressure. Body mass index (BMI) was objectively measured, while self-reported information on leisure-time physical activity, TV viewing, chronological age, race, educational status, tobacco smoking, sodium consumption, and hypertension medication was obtained using questionnaires. Logistic regression analysis with adjusted odds ratio was conducted to test the joint association of BMI and leisure-time physical activity categories on high blood pressure. Overall, compared to normal weight (NW) and physically active group, the NW/inactive (OR = 1.28; 1.04 to 1.58), overweight/active (OR = 1.38; 1.08 to 1.78), overweight/inactive (OR = 1.89; 1.53 to 2.33), obese/active (OR = 2.19; 1.59 to 3.01) and obese/inactive (OR = 2.54; 2.05 to 3.15) groups were 28% to 254% more likely to have high blood pressure. The attenuation and high blood pressure was greater for women and adults than for men and older adults. Thus, leisure-time physical inactivity and being overweight and obesity were associated with high blood pressure in Brazilian population. Engaging in sufficient level of physical activity during leisure could attenuate, but not eliminate, the negative influence of obesity on high blood pressure in Brazilian adults and older adults., (©2018 Wiley Periodicals, Inc.)

Background: This study aims to describe the regional prevalence and patterns of physical activity (PA) and sedentary behavior among Brazilian adolescents., Methods: Data from the Brazilian Scholar Health Survey, a nationally representative survey of ninth-grade adolescents [mean age: 14.29 y (14.27-14.29)] conducted in 2015 (n = 101,445), were used. Outcomes were television viewing, sitting time (ST), total PA, and active traveling collected via self-administered questionnaire. Information on frequency of physical education classes and type of school was collected from the school's director. Frequencies with 95% confidence intervals were used to determine the prevalence and patterns of outcomes., Results: Higher prevalence of PA (≥300 min/wk) and ST (>4 h/d) was found in Midwest (PA = 38.0%; ST = 44.5%), South (PA = 37.6%; ST = 50.1%), and Southeast (PA = 36.1%; ST = 49.3%) compared with Northeast (PA = 29.7%; ST = 36.9%) and North (PA = 34.4%; ST = 34.8%) regions of Brazil. ST was higher among adolescents from private schools (51.5%) than public schools (42.9%), whereas active traveling was greater among students of public schools than private schools (62.0% vs 34.4%). Most inequalities in outcomes between capital and interior cities were in the poorest regions., Conclusions: The results indicate that national plans targeting regional inequalities are needed to improve PA and to reduce sedentary behavior among Brazilian adolescents.

Background: In pediatric populations, the use of resting heart rate as a health index remains unclear, mainly in epidemiological settings. The aims of this study were to analyze the impact of resting heart rate on screening dyslipidemia and high blood glucose and also to identify its significance in pediatric populations., Methods: The sample was composed of 971 randomly selected adolescents aged 11 to 17 years (410 boys and 561 girls). Resting heart rate was measured with oscillometric devices using two types of cuffs according to the arm circumference. Biochemical parameters triglycerides, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and glucose were measured. Body fatness, sleep, smoking, alcohol consumption and cardiorespiratory fitness were analyzed., Results: Resting heart rate was positively related to higher sleep quality (β = 0.005, p = 0.039) and negatively related to cardiorespiratory fitness (β = -0.207, p = 0.001). The receiver operating characteristic curve indicated significant potential for resting heart rate in the screening of adolescents at increased values of fasting glucose (area under curve = 0.611 ± 0.039 [0.534 - 0.688]) and triglycerides (area under curve = 0.618 ± 0.044 [0.531 - 0.705])., Conclusion: High resting heart rate constitutes a significant and independent risk related to dyslipidemia and high blood glucose in pediatric populations. Sleep and cardiorespiratory fitness are two important determinants of the resting heart rate.