Implementation of different strategies of the "ActTeens" intervention for adolescents: a process evaluation / Implementação das diferentes estratégias da intervenção "ActTeens" para adolescentes: uma avaliação do processo

Multicomponent programs to promote physical activity have shown promise to help adolescents to increase physical activity levels. Although evaluation of the intervention implementation process is important, information about this evaluation is rarely reported. This observational study aimed to evaluate the implementation of a 12-week physical activity intervention program for adolescents. The ActTeens program consists of three components: (1) structured physical activity sessions; (2) self-monitoring associated with daily goal setting; (3) healthy lifestyle messages (mHealth). The evaluation of the process was carried out through observations and self-reported information from the students. Fifty-one adolescents (37.5% girls) answered the questionnaire. Overall, the reach was 73.3%, retention rate 96.3%, and satisfaction with the intervention was high (score 5). The structured sessions presented high fidelity, and good acceptability among adolescents, with an average attend-ance rate of 93.7%. Participants rated the sessions as enjoyable and the teacher's role as excellent. Adherence to self-monitoring (goal setting with a pedometer) was moderate and 57.8% of adoles-cents reported using the device daily. In addition, adolescents reported that the use of a pedometer increased their motivation to practice physical activity (72.4%). Satisfaction with the messages was considered low, with only 37.8% agreeing that the messages promoted the adoption of a healthy lifestyle. In conclusion, the structured sessions and the self-monitoring showed good acceptability among adolescents, and these strategies were considered relevant to promote a more physically active lifestyle. However, the component mHealth, when used as a single strategy, did not aid the adoption of healthy behavior

Programas multicomponentes para promoção da atividade física têm se mostrado promissores para auxiliar os adolescentes a aumentar seus níveis de atividade física. Embora a avaliação do processo de implementação da intervenção seja importante, informações sobre esta avaliação raramente são relatadas. O presente estudo teve como objetivo avaliar a implementação de um programa de intervenção de atividade física de 12 sema-nas para adolescentes. O programa ActTeens consiste de três componentes principais: (1) sessões estruturadas de atividade física; (2) auto-monitoramento associado com estabelecimento de metas diárias; (3) orientações sobre um estilo de vida saudável (mHealth). A avalição do processo foi por meio de observações e informações autorreferidas dos alunos. Cinquenta e um adolescentes (37,5% meninas) responderam o questionário. No geral, o alcance foi de 73,3%, a taxa de retenção 96,3% e satisfação com a intervenção foi alta (escore 5). As sessões estruturadas tiveram alta fidelidade, boa aceitabilidade entre os adolescentes com a frequência média de participação de 93,7% por aula. Os participantes classificaram as sessões como prazerosas e o papel do pro-fessor como excelente. A aderência ao automonitoramento (estabelecimento de metas com pedômetro) foi mode-rada e 57,8% dos adolescentes relataram usar o dispositivo diariamente. Além disso, os adolescentes relataram que o uso do pedômetro aumentou a motivação para a prática de atividade física (72,4%). A satisfação com as mensagens por aplicativo foi considerada baixa, sendo que apenas 37,8% concordaram que as mensagens promoveram a adoção de um estilo de vida saudável. Em conclusão, as sessões estruturadas e o uso do pedô-metro para automonitoramento mostraram boa aceitabilidade entre os adolescentes, e estas estratégias foram consideradas relevantes para promover um estilo de vida fisicamente mais ativo. Entretanto, o componente mHealth, quando usado como uma estratégia única, não auxiliou na adoção de um comportamento saudável

Improving physical activity behaviors, physical fitness, cardiometabolic and mental health in adolescents - ActTeens Program: A protocol for a randomized controlled trial.

This trial aims to investigate the effects of the ActTeens physical activity program, on adolescents' physical activity level, health-related fitness, cardiometabolic and mental health. The trial will aim to recruit ~140 adolescents (aged 13-14 years). Participants will be randomized into either intervention or control groups. The intervention will be guided by social cognitive theory and self-determination theory and implemented over one school term (24-weeks). The ActTeens Program will include: (1) structured physical activity sessions delivered within physical education, including movement-based games and dynamic stretching warm-ups; resistance training skill development; high-intensity training workouts; and cool-downs; (2) self-monitoring plus goal setting for physical activity by pedometer-smart wearable; and (3) healthy lifestyle guidance (social support) by WhatsApp® messages about healthy eating and regular physical activity for the intervention and parents groups. Study outcomes will be assessed at baseline, 24-weeks from baseline, and 12-months from baseline. Physical activity (accelerometer) is the primary outcome. Secondary outcomes include muscular and cardiorespiratory fitness, cardiometabolic profile, and mental health. A process evaluation will be conducted (i.e., recruitment, retention, attendance, and program satisfaction). This project will have the potential to address many questions and debates regarding the implementation of physical activity interventions in low-and- middle-income countries. Trial registration: ClinicalTrials.gov NCT05070377. Registered on 7 October 2021.

Acute Perceptive Responses to 2 Combined Training Methods in Adolescents: A Crossover Study.

OBJECTIVE: To compare the acute perceptive responses of different combined training methods in adolescents. MATERIALS AND METHODS: The sample consisted of 50 adolescents, insufficiently active, aged between 14 and 18 years (58% female). The adolescents performed 2 sessions in a randomized order: moderate-intensity continuous training + resistance training (MICT + RT) and high-intensity interval training + resistance training (HIIT + RT). The rating of perceived exertion, affect, and satisfaction were measured by self-report in 5 moments during the combined training (HIIT or MICT-moments 1, 2, and 3; RT-moments 4 and 5) and 10 minutes after the end of the session. RESULTS: During HIIT, adolescents reported higher values of rating of perceived exertion compared to the MICT session at moments 2 and 3 in both sexes (P < .05). In addition, at moments 2 and 3 of the HIIT session, female participants were reported to have a higher value of satisfaction compared to MICT (F = 3.953; P = .005; η2 = .067). CONCLUSION: During the execution of both HIIT + RT and MICT + RT protocols, adolescents showed an increase in the values of pleasure and satisfaction, regardless of sex.

Efeitos de diferentes métodos de treinamento na melhora dos indicadores cardiometabólicos em corredores recreacionais: uma revisão sistemática / Effects of different training methods in improving cardiometabolic indicators in recreational runners: a systematic review

: O exercício físico, em especial a corrida de rua tem sido recomendada para prevenção e tratamento de doenças crônicas não transmissíveis. O objetivo desta revisão sistemática foi verificar os efeitos de diferentes métodos de treinamento sobre os indicadores cardiometabólicos de corredores recreacionais. As bases de dados eletrônicas utilizadas na presente pesquisa foram: PUBMED, SCIENCE DIRECT, LILACS e COCHRANE LIBRARY, usando os descritores agrupados segundo o método PICO; População ("adults" OR "young adult" OR "middle aged") AND Intervenção ("endurance training" OR "aerobic training" OR "running") OR Comparação ("recreational runners" OR "jogging") AND Outcome/Desfecho ("cardiovascular risk factors" OR "cardiometabolic risk factors" OR "metabolic syndrome"). Na seleção os artigos foram excluídos por título, resumo e texto. Obteve-se um total de 813 artigos encontrados, no qual nove (9) preencheram os critérios de inclusão e baixo risco de viés de acordo com a Escala Testex. Foram encontrados três métodos de treinamento: Combinado (Contínuo +Intervalado); Contínuo e Intervalado. Considerando a somatória das amostras dos nove estudos, um total de 604 indivíduos (466 homens e 138 mulheres) participaram dos ensaios. Os diferentes métodos de treinamentos resultaram na redução dos níveis de triglicerídeos, insulina e glicose e na redução do colesterol total e LDL, e consequentemente o aumento do HDL. Na composição corporal houve diminuição significativa do peso e da gordura corporal, do IMC, na medida da circunferência da cintura, e no aumento da capacidade aeróbia (VO2). Concluiu-se que os treinamentos combinado, contínuo e intervalado podem ser aplicados para melhora dos indicadores cardiometabólicos, cada um dentro da sua especificidade de frequência, volume e intensidade.(AU)

Physical exercise, especially running, has been recommended for the prevention and treatment of chronic non-communicable diseases. The objective of this systematic review was to verify the effects of different training methods on the cardiometabolic indicators of recreational runners. The electronic databases used in the present research were: PUBMED, SCIENCE DIRECT, LILACS and COCHRANE LIBRARY, using the descriptors grouped according to the PICO method; Population ("adults" OR "young adult" OR "middle aged") AND Intervention ("endurance training" OR "aerobic training" OR "running") OR Comparison ("recreational runners" OR "jogging") AND Outcome / Outcome ("Cardiovascular risk factors" OR "cardiometabolic risk factors" OR "metabolic syndrome"). In the selection, articles were excluded by title, abstract and text. A total of 813 articles were obtained, in which nine (9) met the inclusion criteria and low risk of bias according to the Testex Scale. Three training methods were found: Combined (Continuous + Interval); Continuous and Interval. Considering the sum of the samples from the nine studies, a total of 604 individuals (466 men and 138 women) participated in the trials. The different training methods resulted in a reduction in the levels of triglycerides, insulin and glucose and in the reduction of total cholesterol and LDL, and consequently an increase in HDL. In body composition, there was a significant decrease in weight and body fat, in BMI, as measured by waist circumference, and in increased aerobic capacity (VO2). It is concluded that combined, continuous and interval training can be applied to improve cardiometabolic indicators, each within its specific frequency, volume and intensity.(AU)

Physical Activity, Sport Practice and Cardiovascular Risk Factors in Workers From a Public Hospital: A Trajectory Analysis.

Background: Studies have demonstrated the positive effects of physical activity on cardiovascular risk factors. Longitudinal studies using modeled trajectories are necessary to understand patterns of physical activity and association with cardiovascular risk factors. Objective: To analyze the association between sports practice in young people and current physical activity with the trajectory of cardiovascular risk factors in workers at a public hospital. Methods: Four hundred and seventeen workers was followed for four years reporting Physical Activity, health status, lifestyle behaviors and socio-demographic characteristics. Group-based trajectory modeling identified the trajectories of PA and associations with time-stable and time-varying covariates. We considered a range of sociodemographic and health and lifestyle factors as potential covariates. Results: The results shows the association between participation in sports activities in youth and current physical activity and trajectories of cardiovascular risk, adjusted for sex and age (p < 0.05). Adults who reported having played sports in their youth and are currently active have a lower risk of having a history of obesity and low HDL-c than workers who did not play sports in their youth and are currently sedentary 0.690 (0.565-0.844) obesity, 0.647 (0.500-0.837) low HDL-c. Conclusion: The practice of sports in youth and current physical activity is a protective factor against the trajectory of obesity and low HDL-c, mainly in female workers. Programs to encourage the practice of physical activity should be carried out in order to reduce cardiovascular risk factors and prevent chronic diseases in workers.

Hiit, resistance training, and risk factors in adolescents: a systematic review / Hiit, treinamento resistido e fatores de risco em adolescentes: uma revisão sistemática / Hiit, entrenamiento resistido y factores de riesgo en adolescentes: una revisión sistemática

ABSTRACT It has been shown that combined physical exercise is an efficient non-pharmacological approach in the context of public health, since it has demonstrated satisfactory results in the prevention, treatment and control of various morbidities. Therefore, it is essential to systematize current knowledge to enable professionals involved in the prescription of physical exercise to do so based on evidence. Thus, the objective of this study was to perform a systematic review of randomized clinical trials to verify changes in cardiometabolic risk factors induced by high-intensity interval training (HIIT) and resistance training (RT) in adolescents. The systematic search was performed in the following databases: Pubmed, ScienceDirect, Cochrane, LILACS and Scielo. Initially 933 studies were identified, then two researchers eliminated duplications and manuscripts that did not meet the eligibility criteria. Thus, two articles were included that met these criteria: a randomized clinical trial conducted with adolescents (10 to 19 years) of both sexes, an intervention lasting for at least four weeks, which prescribed HIIT and RT in the same session or not, and evaluation of at least one cardiometabolic risk factor. The results demonstrated that eight to 12 weeks of HIIT and RT without nutritional intervention were effective in significantly reducing waist circumference and body fat percentage. However, data pertinent to the efficacy of this combination on risk of developing type 2 diabetes mellitus and arterial hypertension are controversial. In view of the above, it is ascertained from the included studies that the combination of HIIT and RT has the potential to reduce cardiometabolic risk factors in adolescents; therefore, further studies should be conducted to determine the effectiveness of this prescription of physical exercise. Level of Evidence II; Systematic review of Level II or Level I Studies with discrepant results.

RESUMO Tem sido evidenciado que o exercício físico combinado é uma abordagem não farmacológica eficiente no âmbito da saúde pública, uma vez que tem demonstrado resultados satisfatórios na prevenção, tratamento e controle de diversas morbidades. Portanto, é essencial a sistematização do conhecimento atual para que profissionais envolvidos na prescrição de exercícios físicos possam fazê-lo baseados em evidências. Dessa forma, o objetivo do presente estudo foi realizar uma revisão sistemática de ensaios clínicos randomizados para verificar as alterações dos fatores de risco cardiometabólicos induzidas pelo treinamento intervalado de alta intensidade (HIIT) e treinamento resistido (TR) em adolescentes. A busca sistemática foi realizada nas seguintes bases de dados: Pubmed, ScienceDirect, Cochrane, LILACS e Scielo. Inicialmente foram identificados 933 estudos, em seguida, dois pesquisadores eliminaram as duplicações e os manuscritos que não atenderam aos critérios de elegibilidade. Assim, foram incluídos dois artigos que atenderam aos critérios de inclusão: ensaio clínico randomizado conduzido com adolescentes (10 a 19 anos) de ambos os sexos, intervenção com duração de, pelo menos, quatro semanas, que prescreveu HIIT e TR na mesma sessão ou não, e avaliação de, pelo menos, um fator de risco cardiometabólico. Os resultados demonstraram que oito a 12 semanas de HIIT e TR, sem intervenção nutricional, foram eficazes para reduzir significativamente a circunferência da cintura e o percentual de gordura. Entretanto, os dados pertinentes à eficácia dessa combinação sobre o risco de desenvolvimento de diabetes mellitus tipo 2 e hipertensão arterial são controversos. Diante do exposto, verifica-se, a partir dos estudos incluídos, que a combinação de HIIT e TR tem o potencial de reduzir fatores de risco cardiometabólicos em adolescentes, portanto, novos estudos devem ser realizados para determinar a efetividade dessa prescrição de exercícios físicos. Nível de Evidência II; Revisão sistemática de Estudos de Nível II ou Nível I com resultados discrepantes.

RESUMEN Se ha evidenciado que el ejercicio físico combinado es un enfoque no farmacológico eficiente en el ámbito de la salud pública, ya que ha demostrado resultados satisfactorios en la prevención, tratamiento y control de diversas morbilidades. Por lo tanto, es esencial la sistematización del conocimiento actual, para que los profesionales involucrados en la prescripción de ejercicios físicos puedan hacerlo basándose en evidencias. De esta forma, el objetivo del presente estudio fue realizar una revisión sistemática de ensayos clínicos aleatorizados para verificar los cambios de los factores de riesgo cardiometabólicos inducidos por el entrenamiento en intervalos de alta intensidad (HIIT) y entrenamiento resistido (ER) en adolescentes. La búsqueda sistemática se realizó en las siguientes bases de datos: Pubmed, ScienceDirect, Cochrane, LILACS y Scielo. Inicialmente se identificaron 933 estudios, luego dos investigadores eliminaron las duplicaciones y los manuscritos que no cumplieron los criterios de elegibilidad. Así, se incluyeron dos artículos que cumplieron estos criterios de inclusión: ensayo clínico aleatorizado conducido con adolescentes (10 a 19 años) de ambos sexos, intervención con una duración de al menos cuatro semanas, que prescribió HIIT y ER en la misma sesión o no, y evaluación de al menos un factor de riesgo cardiometabólico. Los resultados demostraron que ocho a 12 semanas de HIIT y ER, sin intervención nutricional, fueron eficaces para reducir significativamente la circunferencia de la cintura y el porcentaje de grasa. Sin embargo, los datos pertinentes sobre la eficacia de esta combinación sobre el riesgo de desarrollar diabetes mellitus tipo 2 e hipertensión arterial son controvertidos. Delante de lo expuesto se verifica, a partir de los estudios incluidos, que la combinación de HIIT y ER tiene el potencial de reducir factores de riesgo cardiometabólicos en adolescentes, por lo tanto, deben ser realizados nuevos estudios para determinar la efectividad de esa prescripción de ejercicios físicos. Nivel de evidencia II; Revisión sistemática de Estudios de Nivel II o Nivel I con resultados discrepantes.

Tempo de prática de atividade física de intensidade moderada a vigorosa e marcadores de síndrome metabólica em adolescentes / Time of practice of moderate to vigorous physical activity and markers of metabolic syndrome in adolescents

Intervenções envolvendo aumento da atividade física em adolescentes mostram-se promissoras em relação à redução de fatores de risco para a síndrome metabólica (SM). Entretanto, ainda não está bem estabelecido o efeito decorrente do acúmulo da atividade física nos dias de semana, final de semana e total. O objetivo do presente estudo foi verificar a correlação da prática de atividade física de intensidade moderada à vigorosa (AFMV), nos dias de semana (AFMV-DS), final de semana (AFMV-FS) e total (AFMV-T), com a SM e seus fatores. Foram avaliados 109 adolescentes de 10 a 16 anos de idade (66% do sexo feminino). A SM foi definida pelos marcadores: circunferência da cintura (CC), pressão arterial (PA), triglicérides, HDL-C e glicemia em jejum. O tempo em AFMV foi mensurada por acelerômetros ActiGraph modelo GT3X (≥ 4 dias de uso, sendo ≥ 1 de final de semana, ≥ 10 horas/dia de uso). O coeficiente de correlação de Spearman foi utilizado para a verificação da associação entre o escore "z" da prática de atividade física (AFMV-DS, AFMV-FS e AFMV-T) com o escore de cada fator da SM e o escore de SM (média dos fatores da SM). Foi verificada correlação inversa entre AFMV-FS e CC (rho = -0,20), PA sistólica (rho = -019) e SM (rho = -0,20). A AFMV-T apresentou correlação inversa com triglicerídeos (rho = -0,19). As magnitudes das correlações revelam pouco ou nenhum efeito. Conclui-se que de forma geral a AFMV parece apresentar pouca correlação com a SM e seus fatores, mas pode ter alguma contribuição em estratégias multifatoriais de tratamento ou prevenção

Interventions involving increased physical activity in adolescents are promising in terms of reducing risk factors for metabolic syndrome (MS). However, is not well established the effect resulting from the accumula-tion of physical activity on weekdays, weekends and total. The objective of the present study was to verify the correlation between moderate-to-vigorous physical activity (MVPA), on weekdays (MVPA-WD), weekend days (MVPA-WE) and total (MVPA-T), with SM and its factors. 109 adolescents aged 10 to 16 years (66% female) were evaluated. MS was defined by the markers: waist circumference ( WC), blood pressure (BP), triglycerides, HDL-C and fasting blood glucose. MVPA time was measured by ActiGraph accelerators model GT3X (≥ 4 days of use, ≥ 1 at the weekend, ≥ 10 hours/day of use). Spearman's correlation coefficient was used to verify the association between the "z" score of physical activity (MVPA-WD, MVPA-WE and MVPA-T) with the "z" score of each of the SM factors and the SM score (mean of SM factors). An inverse correlation was found between MVPA-WE and WC (rho = -0.20), systolic BP (rho = -019) and SM (rho = -0.20). MVPA-T showed an inverse correlation with triglycerides (rho = -0.19). The magnitudes of the cor-relations reveal little or no effect. It is concluded that, in general, MVPA seems to have little correlation with MS and its factors, but it could have some contribution in multifactorial treatment strategies or prevention

O tempo sentado está associado aos fatores de risco cardiometabólicos em adolescentes? / Is sitting time associated with cardiometabolic risk factors in adolescents?

O presente estudo teve como objetivo verificar a associação entre o tempo sentado e fatores de risco cardiometabólicos em adolescentes. A amostra foi composta por 454 adolescentes (50,6% masculino) com idades entre 12 a 18 anos. O tempo diário despendido sentado e a prática de atividade física moderada-vigorosa foram avaliados por meio do recordatório de três dias de Bouchard. Os fatores de risco cardiometabólicos analisados foram: circunferência de cintura; glicose; HDL-C; triglicerídeos; e pressão arterial. Foi utilizada a análise de variância com dois fatores (sexo e quartis) para comparar os fatores de risco cardiometabólicos entre os quartis de tempo sentado. Para verificar a associação entre o tempo sentado e os fatores de risco cardiometabólicos foi empregado a regressão linear múltipla. Foi observado que os meninos pertencentes ao 4º quartil (maior tempo sentado) apresentaram valores mais elevados de glicose e triglicerídeos em comparação com seus pares com menos tempo. No sexo feminino, verificou-se que as pertencentes ao 3º e 4º quartil apresentaram maiores valores de triglicerídeos e glicose em comparação ao 1º quartil. Associações positivas e significativas foram observadas entre o tempo sentado e os valores de circunferência da cintura (ß = 0,093; p < 0,05), glicose (ß = 0,111; p < 0,05) e pressão arterial diastólica (ß = -0,115; p < 0,05) mesmo após o ajuste para a prática de atividade física moderada-vigorosa. De acordo com os achados do presente estudo, conclui-se que os adolescentes que permaneceram maior tempo sentado apresentaram maiores valores de glicose, triglicerídeos e escore de risco cardiometabólico em comparação aos que despenderam menos tempo

This study aimed to verify if there is an association between sitting time and cardiometabolic risk factors in adolescents. The sample was composed of 454 adolescents (50.6% male) aged between 12 and 18 years. The time spent in sitting and physical activity were assessed through a record of three days by Bouchard. The following cardiometabolic risk factors were analyzed: waist circumference, glucose, HDL ­ cholesterol, tri-glycerides, and blood pressure. It was used the Two-way Analysis of Variance (sex and quartiles) to compare the cardiometabolic risk factors between the quartiles of sitting time. To verify the association between sitting time and cardiometabolic risk factors it was used the multivariate linear regression. Boys of the 4th quartile (higher sitting time) presented higher values of glucose and triglycerides compared to their peers with less time. Girls of the 3rd and 4th quartile presented higher triglycerides and glucose values, compared to the 1st quartile. Significant associations (p < 0.05) were observed between sitting time with waist circumference (ß = 0.093; p < 0.05), glucose (ß = 0.111; p < 0.05) and diastolic blood pressure (ß = 0.115; p < 0.05) even after the adjustment for the moderate to vigorous physical activity. According to the findings of this study, we concluded that adolescents who spent more sitting time had higher values of glucose, triglycerides and cardiometabolic risk score compared with who has less sitting time

Effects of 2 Methods of Combined Training on Cardiometabolic Risk Factors in Adolescents: A Randomized Controlled Trial.

PURPOSE: To analyze the effects of 2 combined training methods on the cardiometabolic risk factors in adolescents. METHODS: A total of 76 adolescents (16.1 [1.1] y, n = 44 female) were randomized into groups of moderate-intensity continuous training combined with resistance training (MICT + RT), high-intensity interval training combined with resistance training (HIIT + RT), or control. The training sessions were performed twice weekly for 12 weeks. The outcomes evaluated included body fat percentage, waist circumference, fasting blood glucose, fasting insulin, total cholesterol, triglycerides, low-density lipoprotein, high-density lipoprotein, glycated hemoglobin, insulin resistance index, blood pressure, peak oxygen consumption (VO2peak), and cardiometabolic risk Z score. RESULTS: The intervention groups presented a significant reduction in the cardiometabolic risk Z score after 12 weeks of the combined exercise program. In relation to the cardiometabolic risk Z score between groups, the HIIT + RT group presented a significant intervention effect when compared with the control group (Cohen d = 0.23; P < .05). Significant intervention effects were found when comparing the MICT + RT and control groups for body fat percentage, high-density lipoprotein, and VO2peak. Between the HIIT + RT and control groups, significant intervention effects were found for body fat percentage, blood pressure, and VO2peak. There were not significant differences between the HIIT + RT and MICT + RT groups. CONCLUSION: Twelve weeks of HIIT + RT and MICT + RT were effective in significantly reducing the cardiometabolic risk in these adolescents.

Health-related physical fitness indicators and clustered cardiometabolic risk factors in adolescents: A longitudinal study.

BACKGROUND/OBJECTIVE: This study examined relationships between health-related physical fitness indicators and clustered cardiometabolic risk factors in adolescents between 2014 and 2017. METHODS: The sample consisted of 93 students (60% girls), with complete data sets in both 2014 and 2017. The physical fitness components evaluated were: flexibility (sit and reach), muscular fitness (curl-up and push-up), cardiorespiratory fitness (progressive aerobic cardiovascular endurance run), and body fat (BMI). The cardiometabolic risk factors were: waist circumference, blood pressure, high-density lipoprotein cholesterol (HDL-C), triglycerides and fasting blood glucose. Z-scores were calculated for each risk factor, with the sum of risk factor z-scores values used to represent clustered cardiometabolic risk. RESULTS: The results of cross-sectional analysis indicated that muscle fitness (curl-up: ß = -0.37, p < 0.001; push-up: ß = -0.38, p < 0.005) and cardiorespiratory fitness (ß = -0.56, p < 0.001) were inversely associated with clustered cardiometabolic risk, with BMI positively associated (ß = 0.58, p < 0.001). In the longitudinal analysis, cardiorespiratory fitness (ß = -0.33; p < 0.005) and body fat (ß = 0.46, p < 0.001) demonstrated a significant association with clustered cardiometabolic risk. However, no significant associations between the health-related physical fitness and clustered cardiometabolic risk were observed after adjustment for baseline values. CONCLUSION: Our cross-sectional findings highlight the importance of health-related physical fitness indicators to adolescents. In regarding the longitudinal analysis, further studies are needed in order to clarify the influence of physical fitness in the adolescence and cardiometabolic risk later in life.

Acute effects of physical exercise at different intensities on inflammatory markers in obese adolescents / Efeito agudo do exercício físico em diferentes intensidades sobre os marcadores inflamatórios em adolescentes obesos

ABSTRACT Obesity promotes a state of chronic low-grade inflammation of white adipose tissue, which is associated with different chronic diseases. While exercise induces an anti-inflammatory environment, little is known about the acute effects of continuous exercise at different intensities on inflammatory markers in obese adolescents. This study included 10 obese adolescents of both sexes, between 15 and 18 years of age. Volunteers performed two 30-minute exercise sessions. The 1st exercise session was performed at moderate intensity (55% VO2peak) and the 2nd at vigorous intensity (75% VO2peak), with a one-week interval between sessions. Blood samples were collected 10 minutes before and 20 minutes after the exercise sessions. Inflammatory markers were analyzed using the chemiluminescence method. Statistical analysis was performed using the two-factors ANOVA test for repeated measures and statistical significance was set at 5% (p <0.05). The results showed that 30 minutes of moderate aerobic exercise resulted in significant changes in circulating levels of TNF-α (6.23 ± 1.64 to 7.03 ± 1.49) and IL-6 (3.35 ± 1.53 to 3.85 ± 1.73). The results of this study showed that a single exercise session of moderate intensity lasting for 30 minutes induced acute responses in inflammatory markers in the obese adolescents evaluated.

RESUMO A obesidade promove um estado de inflamação crônica de baixo grau do tecido adiposo branco, o qual está associado a doenças crônicas. O exercício físico induz um ambiente anti-inflamatório, porém pouco se sabe sobre o efeito agudo do exercício físico contínuo em diferentes intensidades sobre os marcadores inflamatórios em adolescentes obesos. Participaram deste estudo 10 adolescentes obesos de ambos os sexos, entre 15 e 18 anos. Os voluntários realizaram duas sessões de 30 minutos de exercício, sendo a 1ª sessão na intensidade moderada (55% VO2pico) e a 2ª sessão na intensidade vigorosa (75% VO2pico), com o intervalo de uma semana entre cada sessão. As amostras sanguíneas foram coletadas 10 minutos pré e 20 minutos pós exercício. Os marcadores inflamatórios foram analisados através do método Quimiluminescência. Para análise estatística foi utilizado o teste ANOVA para medidas repetidas com dois fatores e o nível de significância adotado foi de 5% (p< 0,05). Os resultados indicaram que 30 minutos de exercício aeróbico moderado resultou em mudanças significativas nos níveis circulatórios de TNF-α (6,23 ± 1,64 para 7,03 ± 1,49) e IL-6 (3,35 ± 1,53 para 3,85 ± 1,73). A partir dos resultados encontrados no presente estudo, pode-se concluir que uma única sessão de exercício físico de intensidade moderada com 30 minutos de duração induziu respostas agudas nos marcadores inflamatórios nestes adolescentes obesos

Exercício intervalado de alta intensidade e pressão arterial ambulatorial de adolescentes obesos / High-intensity interval exercise and ambulatory blood pressure of obese adolescents

O objetivo deste estudo foianalisar o comportamento da pressão arterial ambulatorial de adoles-centes obesos após uma sessão de exercício intervalado de alta intensidade (HIT) na esteira ergo-métrica. Trata-se de uma pesquisa com delineamento cross-over randomizado, realizada com nove adolescentes do sexo masculino de 15 a 18 anos de idade. Os voluntários realizaram dois protocolos experimentais, com intervalo mínimo de 48 horas: controle e HIT. O protocolo HIT foi constituído de cinco séries a 85 ­ 95% do VO2pico por um minuto, intercalados por três minutos de recuperação a 40 ­ 50% do VO2pico. Antes e após os protocolos, frequência cardíaca, pressão arterial sistólica (PAS), pressão arterial diastólica e pressão arterial média foram mensuradas na posição sentada. A medida ambulatorial da pressão arterial foi realizada nos dois protocolos por meio de um monitor automá-tico da marca SpaceLabs 90207, programado para realizar medidas a cada 20 minutos, das 12:00 às 22:00 horas. Os efeitos dos protocolos experimentais nas respostas hemodinâmicas foram testados por meio da análise de variância para medidas repetidas, considerando-se os fatores (controle e HIT) e tempo (pré-sessão e pós-sessão). Os resultados apontaram diferença significativa entre as médias da PAS nos protocolos controle e HIT na primeira hora após o final do exercício (133,66 ± 7,56 vs 125,88 ± 7,20 mmHg, respectivamente; p = 0,005), indicando hipotensão pós-exercício induzida pelo HIT. O protocolo HIT empregado promoveu efeito hipotensor de moderada magnitude e curta duração sobre a PAS

The objective of this study was to analyze the behavior of ambulatory blood pressure of obese adolescents after a session of high intensity interval exercise (HIT) on treadmill. This was a randomized cross-over study with nine male adolescents between 15 and 18 years of age. The volunteers performed two experimental pro-tocols with a minimum interval of 48 hours: control and HIT. The HIT protocol consisted of five series at 85 ­ 95% of VO2peak for one minute, interspersed by three minutes of recovery at 40 ­ 50% of VO2peak. Before and after the protocols, heart rate, systolic blood pressure (SBP), diastolic blood pressure and mean arterial pres-sure were obtained in the seated position. Ambulatory blood pressure measurement was performed in both protocols through an automatic monitor of the mark SpaceLabs 90207, programmed to perform measure-ments every 20 minutes from 12:00 to 22:00 hours. The effects of the experimental protocols on hemodynamic responses were tested through analysis of variance for repeated measures, considering the factors (control and HIT) and time (pre-session and post-session). The results showed a significant difference between the means of SBP in the control and HIT protocols in the first hour after the end of the exercise (133.66 ± 7.56 vs 125.88 ± 7.20 mmHg, respectively, p = 0.005), indicating post-exercise hypotension induced by HIT. The HIT protocol employed promoted a moderate magnitude and short duration hypotensive effect on SBP

Tracking of physical activity in adolescents between 2010 and 2014 / Tracking da atividade física em adolescentes entre 2010 e 2014

Abstract Even though the benefits of regular physical activity (PA) are well established, national tracking studies are still scarce. The aim of the study was to analyze the tracking of physical activity (PA) in 2010, 2012 and 2014 of adolescents from Jacarezinho, Paraná. Adolescents (ages: 15.6 ± 0.6 years) were evaluated in 2014, who had participated in the 2010 and 2012 surveys. The Baecke questionnaire was used to evaluate the physical activity fields: school, sports and leisure time. ANOVA for repeated measures was used to compare the physical activity index (PAI) in years 2010, 2012 and 2014. The Spearman correlation coefficient was used to relate PAI obtained in 2014 with previous years. Significant reduction was observed in both sexes in the total and school index in 2012 and 2014 in relation to 2010. The leisure time index also presented a significant reduction in male sex from 2012 to 2014 (p<0.05). In the correlation between 2014 and the previous years, boys demonstrated weak association in the leisure index in 2010 (rho=0.292). In the female sex, values were significant in the leisure time and total indexes (rho=0.263; rho=0.307) in 2010 and in the sports and total indexes (rho=0.337; rho=0.332) in 2012. The research indicates that PA of adolescents decreased with age advancement, resulting in low to moderate tracking.

Resumo Embora os benefícios da prática regular de atividade física (AF) estejam bem estabelecidos na literatura, estudos nacionais de rastreamento (tracking) ainda são escassos. O objetivo do estudo foi analisar o tracking da atividade física entre 2010, 2012 e 2014 em adolescentes de Jacarezinho, Paraná. Foram avaliados em 2014 adolescentes (idades: 15,6 ± 0,6 anos) que já tinham participado do levantamento em 2010 e 2012. A atividade física foi avaliada pelo questionário de Baecke nos domínios: escolar, esportivo e lazer. ANOVA para medidas repetidas foi adotada para comparar os índices de atividade física (IAF) entre 2010, 2012 e 2014. O coeficiente de correlação de Spearman foi empregado para associar os IAF obtidos em 2014 com os anos anteriores. Foi observada redução significativa em ambos os sexos nos índices total e escolar de 2012 e 2014 em comparação ao ano de 2010. O índice lazer também apresentou redução significativa no sexo masculino de 2012 a 2014 (p<0,05). Na correlação entre 2014 e os anos anteriores, os meninos demonstraram fraca associação no índice lazer em 2010 (rho=0,292). Já no sexo feminino, os valores foram significativos nos índices lazer e total (rho=0,263; rho=0,307) em 2010 e nos índices esportivo e total (rho=0,337; rho=0,332) no ano de 2012. Os achados indicam que a AF dos adolescentes diminuiu com o avanço da idade, tendo como resultado o tracking fraco a moderado.

Number of days required for reliably estimating physical activity and sedentary behaviour from accelerometer data in older adults.

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 h.day-1) 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.

Efeitos de uma intervenção com pedômetro sobre o risco metabólico em crianças obesas / Effects of an intervention with pedometer on metabolic risk in obese children / Efectos de una intervención con podómetro en el riesgo metabólico en niños obesos

RESUMO Introdução: Nas últimas décadas, a incidência de obesidade na população pediátrica vem aumentando, juntamente com a inatividade física. A obesidade e a inatividade física são componentes predisponentes para o agravo dos fatores de risco metabólico, sendo de fundamental importância seu tratamento visando melhora da saúde dos jovens. Objetivo: Verificar o efeito de 12 semanas de uma intervenção focada na atividade física sobre os fatores de risco metabólico em crianças obesas. Métodos: A amostra final foi composta por 19 escolares com idade entre oito e 10 anos (10 no grupo pedômetro e nove no grupo controle). A atividade física foi mensurada e orientada por meio do pedômetro Yamax(r) sw 700 (Tóquio, Honchu, Japão). Para comparações intra e entre grupos foi aplicado a ANOVA two way para medidas repetidas com significância estipulada em p < 0,05. Resultados: O número de passos aumentou significativamente somente no grupo pedômetro após as 12 semanas de intervenção (pré 9729,7 ± 2539,8 vs. pós 13151,6 ± 3581,7). Foi observado aumento significativo do peso corporal, da estatura e do IMC no grupo controle. No grupo pedômetro, observou-se aumento significativo apenas na estatura. Com relação aos fatores de risco metabólicos, não foi encontrada mudança significativa no grupo controle, enquanto no grupo pedômetro foi observada diminuição significante nos valores de insulina (pré 12,21 ± 8,53 vs. pós 7,26 ± 4,70 µUI/ml) e HOMA IR (pré 2,76 ± 1,93 vs. pós 1,49 ± 0,93). Conclusão: A presente intervenção com atividade física a partir do estabelecimento de metas utilizando pedômetros reduziu significativamente as concentrações de insulina e o índice de homeostase (HOMA IR) em crianças obesas, independentemente da perda de peso.

ABSTRACT Introduction: In recent decades, the incidence of obesity in children is increasing along with physical inactivity. Obesity and physical inactivity are predisposing components to the worsening of metabolic risk factors and treatment is fundamental aiming at improving the health of young people. Objective: To verify the effect of 12 weeks of an intervention focused on physical activity on metabolic risk factors in obese children. Methods: The final sample consisted of 19 students aged between 8 and 10 years (10 in the pedometer group and nine in the control group). Physical activity was measured and guided by the Yamax(r) sw 700 pedometer (Tokyo, Honshu, Japan). For within and between groups comparisons the two way ANOVA was applied for repeated measures with significance set at p<0.05. Results: The number of steps increased significantly only in the pedometer group after the 12-week intervention (9729.7±2539.8 before vs. 13151.6±3581.7 after). Significant increase was observed in body weight, height, and BMI in the control group. In the pedometer group, it was observed significant increase only in stature. Regarding the metabolic risk factors, there was no significant change found in the control group, while in the pedometer group a significant decrease in insulin levels was observed (12.21±8.53 before vs. 7.26±4.70 µUI/ml after) and HOMA IR (2.76±1.93 before vs. 1.49±0.93 after). Conclusion: This intervention with physical activity from setting goals using pedometers significantly reduced the concentrations of insulin and the homeostasis index (HOMA IR) in obese children regardless of weight loss.

RESUMEN Introducción: En las últimas décadas, la incidencia de la obesidad en los niños es cada vez mayor, junto con la inactividad física. La obesidad y la inactividad física son componentes que predisponen al empeoramiento de los factores de riesgo metabólico, siendo de fundamental importancia el tratamiento destinado a mejorar la salud de los jóvenes. Objetivo: Comprobar el efecto de 12 semanas de una intervención centrada en la actividad física sobre los factores de riesgo metabólico en los niños obesos. Métodos: La muestra final fue de 19 estudiantes de edades comprendidas entre ocho y 10 años (10 en el grupo podómetro y nueve en el grupo de control). La actividad física se midió y fue guiada por el podómetro Yamax(r) sw 700 (Tokio, Honchu, Japón). Para las comparaciones dentro y entre grupos se aplicó la ANOVA de dos vías para medidas repetidas, con una significación establecida en p < 0,05. Resultados: El número de pasos aumentó significativamente sólo en el grupo podómetro después de 12 semanas de intervención (pre 9729,7 ± 2539,8 vs. post 13151,6 ± 3581,7). Se observó un aumento significativo en el peso corporal, la estatura y el IMC en el grupo control. En el grupo podómetro, hubo un aumento significativo sólo en estatura. En cuanto a los factores de riesgo metabólico, no hubo ningún cambio significativo en el grupo control, mientras que en el grupo podómetro se observó disminución significativa de los valores de insulina (pre 12,21 ± 8,53 vs. post 7,26 ± 4,70 µUI/ml) y HOMA IR (pre 2,76 ± 1,93 vs. post 1,49 ± 0,93). Conclusión: Esta intervención con actividad física a partir del establecimiento de metas utilizando podómetros redujo significativamente las concentraciones de insulina y el índice de la homeostasis (HOMA-IR) en niños obesos, independientemente de la pérdida de peso.

School environment, sedentary behavior and physical activity in preschool children / Ambiente escolar, comportamento sedentário e atividade física em pré-escolares

Abstract 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.

Resumo Objetivo: Analisar a atividade física e o comportamento sedentário de pré-escolares durante a permanência na escola e os fatores associados. Métodos: Participaram do estudo 370 pré-escolares de 4 a 6 anos, estratificados de acordo com sexo, idade e região da escola em Londrina (PR). Foi aplicado um questionário às diretoras das pré-escolas para analisar a infraestrutura e o ambiente escolar. A atividade física e o comportamento sedentário foram estimados com acelerômetros por cinco dias consecutivos durante a permanência na escola. A razão de chances (RC) foi estimada por meio da regressão logística binária. Resultados: Na escola, independentemente da idade, os pré-escolares permanecem relativamente mais tempo em comportamento sedentário (89,6%-90,9%), seguido de atividade física leve (4,6%-7,6%), moderada (1,3%-3%) e vigorosa (0,5%-2,3%). A sala de recreação interna (RC=0,20; IC95% 0,05-0,83) e o parque (RC=0,08; IC95% 0,00-0,80) protegem os alunos de 4 anos do comportamento sedentário elevado. Associação inversa foi encontrada entre sala de recreação interna e atividade física (RC=0,20; IC95% 0,00-0,93) nos escolares de 5 anos. Sala de recreação interna (RC=1,54; IC95% 1,35-1,77), parque (RC=2,82; IC95% 1,14-6,96) e recreio (RC=1,54; IC95% 1,35-1,77) são fatores que aumentam a chance dos escolares de 6 anos de serem ativos. Conclusões: A infraestrutura e o ambiente da escola devem ser considerados como estratégias para promover a atividade física e reduzir o comportamento sedentário em pré-escolares.

High Blood Pressure in Adolescents of Curitiba: Prevalence and Associated Factors / Pressão Arterial Alterada em Adolescentes de Curitiba: Prevalência e Fatores Associados

Abstract Background: Arterial 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. Objective: To determine high blood pressure prevalence and its associated factors in adolescents. Methods: A 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. Results: The 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. Conclusion: Positive 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.

Resumo Fundamento: A hipertensão arterial é um grave problema de saúde pública e, nos últimos anos, tem aumentado consideravelmente em jovens. A identificação de fatores associados com essa condição é importante para guiar estratégias de intervenção nessa população. Objetivo: Determinar a prevalência e os fatores associados com a pressão arterial alterada em adolescentes. Métodos: Foi selecionada amostra probabilística de 1.242 adolescentes da rede pública de ensino de Curitiba (PR). Por meio de questionários, foram obtidos o histórico familiar de hipertensão, o gasto energético diário, informações sobre tabagismo, o consumo diário de gorduras e a classificação econômica. A circunferência da cintura foi medida por procedimentos padronizados. A pressão arterial foi aferida com manguitos adequados em 2 dias consecutivos para a confirmação da pressão arterial alterada. Frequências relativas e intervalos de confiança (IC95%) indicaram a prevalência de pressão arterial alterada. Regressões logística bivariadas e multivariadas testaram a associação dos fatores de risco com a pressão arterial alterada. Resultados: A prevalência de pressão arterial alterada foi de 18,2% (IC95% 15,2-21,6). Mais chances de pressão arterial alterada foram encontradas nos indivíduos que possuíam ambos os pais com hipertensão arterial [odds ratio (OR), 2,22; IC95% 1,28-3,85] e naqueles com a circunferência da cintura aumentada (OR, 2,1; IC95% 1,34-3,28). Conclusão: O histórico familiar positivo de hipertensão arterial e a circunferência da cintura aumentada estiveram associados a pressão arterial alterada em adolescentes. Esses fatores são importantes para guiar intervenções futuras nessa população.

High Blood Pressure in Adolescents of Curitiba: Prevalence and Associated Factors.

BACKGROUND: Arterial 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. OBJECTIVE: To determine high blood pressure prevalence and its associated factors in adolescents. METHODS: A 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. RESULTS: The 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. CONCLUSION: Positive 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.

Effect of exercise order on the number of repeats and training volume in the tri-set training method / Efeito da ordem dos exercícios sobre o número de repetições e volume de treino no método de treinamento tri-set

Abstract Although the tri-set system is widely adopted by athletes and experienced weight training practitioners aimed at optimizing the metabolic overload, there are still few works in literature on the effect of exercise order manipulation on this training system. Therefore, this work was aimed at investigating the effect of exercise order manipulation on the number of repeats and training volume using the tri-set system for lower limbs. This is a randomized cross-over design study. The experimental group consisted of 14 healthy men (23.53 ± 5.40 years; 24.51 ± 2.96 kg/m2). Subjects were submitted to two experimental sessions at different exercise order for lower limbs: Sequence A: squat on guided bar, leg press 45° and bilateral leg extension; sequence B: bilateral leg extension, leg press 45° and squat on guided bar. Three sets to volitional fatigue in all exercises were performed, with intensity of 75% 1RM. Superiority for sequence B in the total number of repeats (70.14 ± 13 vs 60.93 ± 7.94 repeats, p = 0.004) and total training volume (9129.64 ± 2830.05 vs 8238.29 ± 2354.20 kg, p = 0.014) was observed. Based on the above, the performance of single-joint exercises before multi-joint exercises in the tri-set system adopted for lower limbs induced higher number of repeats and total training volume.

Resumo Embora o sistema tri-set seja amplamente adotado por atletas e praticantes experientes de treinamento com pesos que buscam otimizar a sobrecarga metabólica, a literatura carece de investigações acerca do efeito da manipulação da ordem dos exercícios nesse sistema de treinamento. Sendo assim, objetivou-se investigar o efeito da manipulação da ordem dos exercícios sobre o número de repetições e volume de treino, utilizando o sistema tri-set para membros inferiores. Trata-se de uma pesquisa com delineamento cross-over aleatorizado. O grupo experimental foi composto por 14 homens saudáveis (23,53 ± 5,40 anos; 24,51 ± 2,96 kg/m2). Os avaliados foram submetidos a duas sessões experimentais em diferentes ordens de exercícios para membros inferiores: sequência A: agachamento na barra guiada, leg press 45° e cadeira extensora bilateral; sequência B: cadeira extensora bilateral, leg press 45° e agachamento na barra guiada. Foram executadas três séries até a fadiga voluntária em todos os exercícios, com intensidade de 75% de 1RM. Observou-se superioridade para a sequência B no número total de repetições (70,14 ± 13,00 vs 60,93 ± 7,94 repetições; p = 0,004) e volume total (9129,64 ± 2830,05 vs 8239,29 ± 2354,20 kg; p = 0,014). Diante do exposto, a execução de um exercício monoarticular antes de multiarticulares, no sistema tri-set adotado para membros inferiores, induziu a um maior número de repetições e volume total de treinamento.

School environment, sedentary behavior and physical activity in preschool children. / Ambiente escolar, comportamento sedentário e atividade física em pré-escolares.

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 to 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 to 0.83) and the playground (OR=0.08; 95%CI 0.00 to 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 to 0.93) in five-year-old children. The indoor recreation room (OR=1.54; 95%CI 1.35 to 1.77), the playground (OR=2.82; 95%CI 1.14 to 6.96) and the recess (OR=1.54; 95%CI 1.35 to 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.