Influence of endurance and resistance exercise order on the postexercise hemodynamic responses in hypertensive women.

The study aims to evaluate the effects of the order of endurance and resistance exercises on postexercise blood pressure (BP) and hemodynamics in hypertensive women. Nineteen hypertensive women underwent 3 sessions: control (50 minutes rest), endurance (50-60% of heart rate reserve) followed by resistance exercise (50% of 1 repetition maximum) (E + R), and resistance followed by endurance exercise (R + E). Before and 30 minutes after each session, BP, peripheral vascular resistance, cardiac output, stroke volume, and heart rate were measured. Postexercise increases in systolic (E + R: +1 ± 3 mm Hg and R + E: +3 ± 3 mm Hg), diastolic (E + R: +3 ± 1 mm Hg and R + E: +3 ± 2 mm Hg), and mean BP (E + R: +3 ± 1 mm Hg and R + E: +3 ± 2 mm Hg) were significantly lower after the exercise sessions compared with the control session (p ≤ 0.05). The exercise sessions abolished the increases in peripheral vascular resistance (E + R: +0.00 ± 0.04 mm Hg·min·L and R + E: +0.05 ± 0.05 mm Hg·min·L) and the decreases in cardiac output (E + R: +0.04 ± 0.28 L·min and R + E: -0.26 ± 0.28 L·min) observed after the control session (p ≤ 0.05). After the exercise sessions, stroke volume decreased (E + R: -14 ± 3 ml and R + E: -9 ± 4 ml) and heart rate increased (E + R: +5 ± 1 b·min and R + E: +4 ± 1 b·min) in comparison with the control session (p ≤ 0.05). For all the variables, there were no significant differences between the exercise sessions. Regardless of the order of endurance and resistance exercises, combined exercise sessions abolished increases in BP observed in a control condition due to a reduction in peripheral vascular resistance and increases in cardiac output. Thus, combined exercises should be prescribed to individuals with hypertension to control their BP, regardless of the order they are accomplished.

Segurança, reprodutibilidade, fatores intervenientes e aplicabilidade de testes de 1-RM / Safety, reliability, intervenient factors and applicability of 1-RM tests

Um dos métodos mais utilizados para mensuração da força muscular é o teste de uma repetição máxima (1-RM), tendo em vista a sua versatilidade para aplicação em diferentes exercícios, a especificidade do movimento e o baixo custo operacional. Neste trabalho discutimos as evidências disponíveis a respeito da segurança, da reprodutibilidade, dos fatores intervenientes e da aplicabilidade prática do teste de 1-RM. Com base nas informações disponíveis até o presente momento, o teste de 1-RM parece ser um método seguro do ponto de vista ortopédico e cardiovascular e a sua reprodutibilidade depende, fundamentalmente, da realização de procedimentos de testagem adequados para a estabilização da carga, assim como do controle dos fatores intervenientes os quais podem influenciar no desempenho do teste. Embora a aplicabilidade para o diagnóstico e acompanhamento da força muscular seja ampla, a utilização de testes de 1-RM para a prescrição de treinamento com pesos ainda é bastante discutível.

One of the most used methods for measuring muscular strength is the one repetition maximum test (1-RM), since its versatility for use in different exercises, its specificity of movement and low operating cost. Despite the advantages, some questions remain unclear. In this study we discuss about the available evidences regarding safety, reproducibility, intervenient factors and the practical applicability of the 1-RM test. The available evidence suggests that the 1-RM test is cardiovascular and orthopedic safely and Its reliability depends on the appropriate test procedures used for load stabilization as well as the control of intervenient factors that may influence the test performance. Although the applicability for the diagnosis and monitoring of muscular strength is large, the use of the 1-RM tests for the prescription of weight training is highly debatable.

Isokinetic strength and endurance in proximal and distal muscles in patients with peripheral artery disease.

BACKGROUND: The objective of this study was to analyze the muscle strength and endurance of the proximal and distal lower-extremity muscles in peripheral artery disease (PAD) patients. METHODS: Twenty patients with bilateral PAD with symptoms of intermittent claudication and nine control subjects without PAD were included in the study, comprising 40 and 18 legs, respectively. All subjects performed an isokinetic muscle test to evaluate the muscle strength and endurance of the proximal (knee extension and knee flexion movements) and distal (plantar flexion and dorsiflexion movements) muscle groups in the lower extremity. RESULTS: Compared with the control group, the PAD group presented lower muscle strength in knee flexion (-14.0%), dorsiflexion (-26.0%), and plantar flexion (-21.2%) movements (P < 0.05) but similar strength in knee extension movements (P > 0.05). The PAD patients presented a 13.5% lower knee flexion/extension strength ratio compared with the control subjects (P < 0.05), as well as lower muscle endurance in dorsiflexion (-28.1%) and plantar flexion (-17.0%) movements (P < 0.05). The muscle endurance in knee flexion and knee extension movements was similar between PAD patients and the control subjects (P > 0.05). CONCLUSION: PAD patients present lower proximal and distal muscle strength and lower distal muscle endurance than control patients. Therefore, interventions to improve muscle strength and endurance should be prescribed for PAD patients.

Reprodutibilidade da medida da pressão arterial auscultatória durante o exercício de força / Reproducibility of auscultatory blood pressure measurement during resistance exercise

O método auscultatório tem sido sugerido como opção viável para a medida da pressão arterial (PA) durante o exercício de força. Todavia, os indicadores de reprodutibilidade deste método durante o exercício de força ainda não foram estabelecidos. O objetivo do estudo foi analisar a reprodutibilidade intra e interavaliadores da medida da PA auscultatória obtida durante o exercício de força. Quatorze sujeitos (24±5 anos; 22,0±2,4 kg/m²; PA sistólica: 116±7 mmHg e PA diastólica: 75±4 mmHg) realizaram três séries de 15 repetições, com 50% de 1-repetição máxima no exercício extensão de joelhos em dois momentos distintos (M1 e M2). Antes e durante os séries, a PA sistólica e diastólica foram medidas em ambos os braços simultaneamente por dois avaliadores. O coeficiente de correlação intraclasse (ICC) intra-avaliador da PA sistólica foi de 0,75 (0,57-0,86) e 0,76 (0,59-0,87) para os avaliadores 1 e 2, respectivamente. Além disso, os valores da PA sistólica foram similares entre o M1 e M2, tanto para o avaliador 1 (144±9 vs 146±18, p=0,08), como para o avaliador 2 (152±9 vs. 153±12, p=0,32). O ICC interavaliadores da PA sistólica foi 0,68 (0,46 - 0,82) e o da PA diastólica foi de 0,21 (0,11-0,50). Pode-se concluir que a medida auscultatória da PA sistólica durante o exercício de força apresenta reprodutibilidade intra e interavaliadores, variando de 0,68 a 0,76, ao passo que a medida PA diastólica, durante o exercício de força, apresenta baixos níveis de reprodutibilidade.

The auscultatory method has been suggested as a viable option for blood pressure (BP) measurement during resistance exercise. However, indicators of reproducibility of this method during resistance exercise have not been established. This study aimed to analyze intra- and inter-examiner reproducibility of auscultatory BP measurements obtained during resistance exercise. Fourteen subjects (24 ± 5 years; 22.0 ± 2.4 kg/m²; systolic BP, 116 ± 7 mmHg; diastolic BP, 75 ± 4 mmHg) performed three sets of 15 repetitions of the knee extension exercise at 50% of their 1-repetition maximum at two different time points (T1 and T2). Before and during exercise, systolic and diastolic BP were measured simultaneously in both arms by two examiners. The intra-examiner intraclass correlation coefficient (ICC) for systolic BP was 0.75 (0.57-0.86) and 0.76 (0.59-0.87) for examiners 1 and 2, respectively. In addition, systolic BP values were similar at T1 and T2 both for examiner 1 (144 ± 9 vs. 146 ± 18, p = 0.08) and examiner 2 (152 ± 9 vs. 153 ± 12, p = 0.32). Inter-examiner ICC was 0.68 (0.46-0.82) for systolic BP and 0.21 (0.11-0.50) for diastolic BP. It can be concluded that auscultatory systolic BP measurement during resistance exercise shows intra- and inter-examiner reproducibility ranging from 0.68 to 0.76, whereas diastolic BP measurement during resistance exercise shows low reproducibility.

Efeito agudo da intensidade do exercício de força na modulação autonômica cardíaca pós-exercício / Acute effect of resistance exercise intensity in cardiac autonomic modulation after exercise / Efecto agudo de intensidad del ejercicio de fuerza en la modulación autónoma del corazón post-ejercicio

FUNDAMENTO: O balanço simpatovagal cardíaco se altera após o exercício de força. Contudo, o impacto das características do treinamento de força nessa resposta ainda não está claro. OBJETIVO: Analisar o efeito agudo da intensidade do exercício de força para tronco e membros superiores na modulação autonômica cardíaca pós-exercício. MÉTODOS: Quinze homens jovens realizaram três sessões experimentais em ordem aleatória: controle (C), exercício de força com 50 por cento de 1-RM (E50 por cento) e exercício de força com 70 por cento de 1-RM (E70 por cento). As sessões incluíram 05 exercícios para tronco e membro superior, realizados em três séries de 12, 9 e 6 repetições, respectivamente. Antes e aos 20 e 50 minutos após as intervenções, a frequência cardíaca foi medida para posterior análise espectral da sua variabilidade. RESULTADOS: Em comparação aos valores anteriores à intervenção, o intervalo RR e a banda de alta frequência (AF) aumentaram (maiores alterações: + 112 ± 83 ms; +10 ± 11 un, respectivamente, p < 0,01), enquanto que a banda de baixa frequência (BF) e a razão BF/AF diminuíram (maiores alterações: -10 ± 11 un; -2 ± 2, respectivamente, p < 0,01) após a sessão C. Nenhuma dessas variáveis se alterou significantemente após a sessão E50 por cento (p > 0,05). Em comparação aos valores pré-exercício, o intervalo RR e a banda AF diminuíram (maiores alterações: -69 ± 105 ms; -13 ± 14 un, respectivamente, p < 0,01), enquanto que a banda BF e a razão BF/AF aumentaram (maiores alterações: -13 ± 14 un, +13 ± 14 un e +3 ± 3 un, respectivamente, p < 0,01) após a E70 por cento. CONCLUSÃO: A maior intensidade de exercício de força para tronco e membros superiores promoveu, agudamente, maior aumento do balanço simpatovagal cardíaco pós-exercício.

BACKGROUND: Cardiac sympathovagal balance is altered after resistance exercise. However, the impact of the characteristics of resistance training in this response remains unclear. OBJECTIVE: Analyze the acute effect of resistance exercise intensity for trunk and upper limbs in cardiac autonomic modulation after exercise. METHODS: Fifteen young men performed three experimental sessions in random order: control (C), resistance exercise with 50 percent of 1-RM (E50 percent) and resistance exercise with 70 percent of 1-RM (E70 percent). The sessions included 05 exercises for the trunk and upper limbs performed in three sets of 12, 9 and 6 repetitions, respectively. Before and at 20 and 50 minutes after the interventions, the heart rate was measured for spectral analysis of variability. RESULTS: In comparison to the values before the intervention, the RR interval and the band of high frequency (HF) increased (major changes: + 112 ± 83 ms; +10 ± 11 un, respectively, p < 0.01), while the low frequency band (LF) and LF/HF ratio decreased (major changes: -10 ± 11 pc; -2 ± 2, respectively, p < 0.01) after the session C. None of these variables changed significantly after the E50 percent session (p > 0.05). Compared to pre-exercise values, the RR interval and the HF band decreased (major changes: -69 ± 105 ms; -13 ± 14 un, respectively, p <0.01), while the LF band and the LF/HF ratio increased (major changes: -13 ± 14 un, 13 ± 3 14 ± 3 and un, respectively, p <0.01) after E70 percent. CONCLUSION: The higher intensity of resistance exercise for trunk and upper limbs promoted, in an acute manner, greater increase in cardiac sympathovagal balance after exercise.

FUNDAMENTO: El balance simpatovogal cardíaco se altera después del ejercicio de fuerza. Sin embargo, el impacto de las características del entrenamiento de fuerza en esta respuesta no está claro. OBJETIVO: Analizar el efecto agudo de intensidad del ejercicio de fuerza para el tronco y miembros en la modulación autonómica del corazón post-ejercicio. MÉTODOS: Quince hombres jóvenes realizaron tres sesiones experimentales en orden aleatorio: control (C), ejercicio de fuerza con el 50 por ciento de 1-RM (E50 por ciento) y ejercicio de fuerza con el 70 por ciento de 1-RM (E70 por ciento). Las sesiones incluyeron 05 ejercicios para tronco y miembro superior, realizados en tres series de 12, 9 y 6 repeticiones, respectivamente. Antes y a los 20 y 50 minutos después de las intervenciones, la frecuencia cardiaca se midió para un análisis espectral posterior de su variabilidad. RESULTADOS: En comparación con los valores anteriores de la intervención, el intervalo RR y la banda de alta frecuencia (AF) se incrementó (cambios importantes: + 112 ± 83 ms; +10 ± 11 un, respectivamente, p < 0,01), mientras que la banda de baja frecuencia (BF) y la razón BF/AF disminuyeron (cambios importantes: -10 ± 11 un; -2 ± 2, respectivamente, p < 0,01) tras la sesión C. Ninguna de estas variables se alteró significantemente tras la sesión E50 por ciento (p > 0,05). En comparación a los valores pre ejercicio, el intervalo RR y la banda AF disminuyeron (cambios importantes: -69 ± 105 ms; -13 ± 14 un, respectivamente, p < 0,01), mientras que la banda BF y la razón BF/AF aumentaron (cambios importantes: -13 ± 14 un, +13 ± 14 un y +3 ± 3 un, respectivamente, p < 0,01) tras la E70 por ciento. CONCLUSIÓN: La mayor intensidad de ejercicio de fuerza para el tronco y miembros superiores produjo de modo agudo, un mayor incremento simpatovagal cardíaco post-ejercicio.

Relação entre aptidão física e os indicadores de qualidade de vida de indivíduos com claudicação intermitente / Correlation between physical fitness and indicators of quality of life of individuals with intermittent claudication

O objetivo deste estudo foi verificar a relação entre a aptidão física e os indicadores de qualidade de vida de indivíduos com claudicação intermitente (CI). Participaram do estudo 42 indivíduos (65,2 ± 8,3 anos) com CI, de ambos os gêneros. Para a avaliação da aptidão física, foram realizados teste de esforço em esteira, para obtenção da distância de claudicação (DC) e da distância total de marcha (DTM) e o teste de uma repetição máxima no exercício extensão de joelho. Os indicadores de qualidade de vida foram avaliados por meio do Medical Outcome Study Questionnaire Short Form 36, composto por oito domínios: capacidade funcional (CF), aspectos físicos (AF), dor, estado geral de saúde, vitalidade (VI), aspectos sociais (AS), aspectos emocionais (AE) e saúde mental. Para a análise estatística foi utilizado o coeficiente de correlação de Pearson, com p < 0,05. Foi observada correlação significante entre o domínio da CF com a DC e a DTM (r = 0,60, p < 0,01 e r = 0,49, p < 0,01, respectivamente), o domínio da AF com a DTM (r = 0,46, p < 0,01), o domínio da VI e dos AS com a DC (r = 0,34, p = 0,03 e r = 0,33, p = 0,04, respectivamente) e o domínio da AE com a DC e a DTM (r = 0,43, p = 0,01 e r = 0,44, p = 0,01, respectivamente). Como conclusão, os resultados deste estudo sugerem que os indicadores da qualidade de vida nos domínios da saúde física e da saúde emocional são relacionados com a capacidade de caminhada de indivíduos com CI.

The aim of this study was to investigate the relationship between physical fitness and the indicators of quality of life in individuals with intermittent claudication (IC). Forty-two subjects (65.2 ± 8.3 years) with IC of both genders participated in the study. Exercise treadmill test, to assess claudication distance (CD) and total walking distance (TWD), and one repetition maximum knee extension test were used to evaluate physical fitness. The quality of life indicators were obtained from the Medical Outcome Study Questionnaire Short Form, which is composed of eight domains: physical functioning (PF), physical aspects (PA), pain, general health, vitality (VI), social functioning (SF), emotional aspects (EA) and mental health. For statistical analysis Pearson correlation coefficient was used, with p < 0.05. There was a significant correlation between PF and CD and TWD (r = 0.60, p < 0.01 and r = 0.49; p < 0.01, respectively), between RP and TWD (r = 0.46, p < 0.01), between VI and SF and CD (r = 0.34, p = 0.03 e r = 0.33, p = 0.04; respectively), and between EA and CD and TWD (r = 0.43, p = 0.01 and r = 0.44, p = 0.01; respectively). In conclusion, the results of this study suggest that indicators of quality of life, both related to physical health and emotional health, are correlated with the walking capacity in patients with IC.

Impact of a supervised strength training or walking training over a subsequent unsupervised therapy period on walking capacity in patients with claudication.

Previous studies have demonstrated that supervised strength training (ST) or walking training (WT) improve walking capacity in patients with claudication. However, it remains unknown whether these improvements would be sustained over a subsequent unsupervised period. This article reports the findings of a study to analyze whether the improvements in walking capacity, achieved with a supervised ST or WT, would be sustained over a subsequent unsupervised therapy period in patients with claudication. Patients were initially randomized to supervised exercise consisting of ST (n = 15) or WT (n = 15) for 12 weeks. After this period, 12 patients in each group consented to be followed for an additional 12 weeks of unsupervised therapy. Initial claudication distance (ICD) and total walking distance (TWD) were measured at baseline, after the supervised period (Week 12) and after the unsupervised period (Week 24). In comparison with baseline values, both groups similarly increased ICD and TWD at Week 12. From Week 12 to Week 24, both groups similarly decreased ICD (ST: -55 ± 110 m and WT: -82 ± 142 m, P =.04) and TWD (ST: -68 ± 186 m and WT: -128 ± 112 m, P < .01). However, in both groups, ICD (ST: +126 ± 149 m and WT: +50 ± 167 m, P = .01) and TWD (ST: +104 ± 162 m and WT: +45 ± 139 m, P =.01) at Week 24 remained greater than baseline values. The conclusion is that supervised ST or WT followed by an unsupervised therapy period similarly decreased walking capacity in patients with claudication. However, after the unsupervised period, walking capacity remained at a higher level than before the onset of the supervised exercise-training period.

Acute effect of resistance exercise intensity in cardiac autonomic modulation after exercise.

BACKGROUND: Cardiac sympathovagal balance is altered after resistance exercise. However, the impact of the characteristics of resistance training in this response remains unclear. OBJECTIVE: Analyze the acute effect of resistance exercise intensity for trunk and upper limbs in cardiac autonomic modulation after exercise. METHODS: Fifteen young men performed three experimental sessions in random order: control (C), resistance exercise with 50% of 1-RM (E50%) and resistance exercise with 70% of 1-RM (E70%). The sessions included 05 exercises for the trunk and upper limbs performed in three sets of 12, 9 and 6 repetitions, respectively. Before and at 20 and 50 minutes after the interventions, the heart rate was measured for spectral analysis of variability. RESULTS: In comparison to the values before the intervention, the RR interval and the band of high frequency (HF) increased (major changes: + 112 ± 83 ms; +10 ± 11 un, respectively, p < 0.01), while the low frequency band (LF) and LF/HF ratio decreased (major changes: -10 ± 11 pc; -2 ± 2, respectively, p < 0.01) after the session C. None of these variables changed significantly after the E50% session (p > 0.05). Compared to pre-exercise values, the RR interval and the HF band decreased (major changes: -69 ± 105 ms; -13 ± 14 un, respectively, p <0.01), while the LF band and the LF/HF ratio increased (major changes: -13 ± 14 un, 13 ± 3 14 ± 3 and un, respectively, p <0.01) after E70%. CONCLUSION: The higher intensity of resistance exercise for trunk and upper limbs promoted, in an acute manner, greater increase in cardiac sympathovagal balance after exercise.

Cardiovascular responses to walking in patients with peripheral artery disease.

PURPOSES: The study's purposes were to assess the cardiovascular responses during constant-load walking and to identify predictors of this response in peripheral artery disease (PAD) patients. METHODS: Seventy-nine patients with PAD performed a constant-load treadmill test (2 mph, 0% grade). During the test, systolic blood pressure (BP), diastolic BP, and HR were obtained at the fourth minute to the last minute of exercise. Patients were also characterized by demographic measures, cardiovascular risk factors, baseline exercise performance, and vascular measures. RESULTS: During constant-load walking, there was a significant increase (P < 0.01) in systolic BP (+12 ± 10 mm Hg), diastolic BP (+6 ± 9 mm Hg), and HR (+5 ± 5 bpm). The HR responses were negatively correlated with the ischemic window (r = -0.23, P < 0.05), expressed as an area under the curve of the resting ankle systolic BP and its recovery from a maximal graded treadmill test, and positively correlated with the HR during the first minute of recovery from the maximal graded treadmill test (r = 0.27, P < 0.05). The increase in cardiovascular variables during constant-load walking was greater in subjects with a higher body mass index and in men (P < 0.05). CONCLUSIONS: Patients with PAD had an increased cardiovascular response during constant-load walking, and these responses were greater in obese patients and in men. The clinical implication is that PAD patients engaged in walking training programs, particularly men and those with obesity, require frequent assessment of cardiovascular parameters to avoid exaggerated increases in BP and HR during constant-load walking.

Abdominal obesity in adolescents: prevalence and association with physical activity and eating habits.

BACKGROUND: Abdominal obesity in adolescents is associated with cardiovascular and metabolic diseases, but its prevalence and the factors associated with its occurrence are unknown. OBJECTIVES: To determine the prevalence of abdominal obesity in adolescents, and to evaluate whether the indicators of physical activity and dietary habits are associated with the occurrence of abdominal obesity in adolescents. METHODS: The sample included 4138 high school students (14-19 years), selected by cluster sampling in two stages. We obtained data using the Global School-based Health Survey, and anthropometric measurements were taken for determination of overweight and abdominal obesity. Logistic regression was used for analysis of behavioral factors associated with the occurrence of abdominal obesity. The identification of cases of abdominal obesity was performed by waist circumference analysis, using age- and gender-related cutoff points as reference. RESULTS: The mean age was 16.8 years (s = 1.4), and 59.8% of subjects were female. The prevalence of abdominal obesity was 6% (95%CI: 5.3-6.7), and it was significantly higher among girls (6.7%, 95%CI: 5.8-7.8) than among boys (4.9%, 95%CI: 3, 9-6, 0). In the crude analysis, gender and overweight were associated with the occurrence of abdominal obesity. The analysis adjustment by logisic regression allowed us to observe that physical activity was significantly associated with the occurrence of obesity in this group (OR = 0.7; 95% CI: 0.49-0.99), regardless of the presence of overweight. CONCLUSIONS: The prevalence of abdominal obesity was low compared to that observed in international studies, and physical activity was a factor associated with the occurrence of this event in adolescents.

Obesidade abdominal em adolescentes: prevalência e associação com atividade física e hábitos alimentares / Abdominal obesity in adolescents: prevalence and association with physical activity and eating habits

FUNDAMENTO: A obesidade abdominal em adolescentes está associada a doenças cardiovasculares e metabólicas, mas a prevalência e os fatores associados à sua ocorrência são ignorados. OBJETIVOS: Determinar a prevalência e verificar se indicadores de atividade física e hábitos alimentares estão associados à ocorrência de obesidade abdominal em adolescentes. MÉTODOS: A amostra compreendeu 4.138 estudantes do ensino médio (14-19 anos), selecionados mediante amostragem por conglomerados em dois estágios. Obtiveram-se os dados por meio do Global School-based Health Survey, enquanto medidas antropométricas foram aferidas para determinação de excesso de peso e obesidade abdominal. Regressão logística binária foi empregada para análise dos fatores comportamentais associados à ocorrência de obesidade abdominal. Identificação dos casos de obesidade abdominal foi efetuada por análise da circunferência da cintura, tomando-se como referência pontos de corte para idade e sexo. RESULTADOS: A idade média foi de 16,8 anos (s =1,4), e 59,8 por cento dos sujeitos eram do sexo feminino; a prevalência de obesidade abdominal foi de 6 por cento (IC95 por cento:5,3-6,7), significativamente superior entre as moças (6,7 por cento; IC95 por cento: 5,8-7,8) em comparação aos rapazes (4,9 por cento; IC95 por cento:3,9-6,0). As análises brutas evidenciaram que sexo e excesso de peso são fatores associados à ocorrência de obesidade abdominal. O ajustamento das análises por regressão logística permitiu observar que a prática de atividades físicas está significativamente associada à ocorrência de obesidade abdominal nesse grupo (OR = 0,7; IC95 por cento:0,49-0,99), independentemente da presença de excesso de peso. CONCLUSÕES: A Prevalência de obesidade abdominal foi baixa em comparação ao observado em levantamentos internacionais, e a prática de atividades físicas é um fator associado à ocorrência desse evento em adolescentes.

BACKGROUND: Abdominal obesity in adolescents is associated with cardiovascular and metabolic diseases, but its prevalence and the factors associated with its occurrence are unknown. OBJECTIVES: To determine the prevalence of abdominal obesity in adolescents, and to evaluate whether the indicators of physical activity and dietary habits are associated with the occurrence of abdominal obesity in adolescents. METHODS: The sample included 4138 high school students (14-19 years), selected by cluster sampling in two stages. We obtained data using the Global School-based Health Survey, and anthropometric measurements were taken for determination of overweight and abdominal obesity. Logistic regression was used for analysis of behavioral factors associated with the occurrence of abdominal obesity. The identification of cases of abdominal obesity was performed by waist circumference analysis, using age- and gender-related cutoff points as reference. RESULTS: The mean age was 16.8 years (s = 1.4), and 59.8 percent of subjects were female. The prevalence of abdominal obesity was 6 percent (95 percentCI: 5.3-6.7), and it was significantly higher among girls (6.7 percent, 95 percentCI: 5.8-7.8) than among boys (4.9 percent, 95 percentCI: 3, 9-6, 0). In the crude analysis, gender and overweight were associated with the occurrence of abdominal obesity. The analysis adjustment by logisic regression allowed us to observe that physical activity was significantly associated with the occurrence of obesity in this group (OR = 0.7; 95 percent CI: 0.49-0.99), regardless of the presence of overweight. CONCLUSIONS: The prevalence of abdominal obesity was low compared to that observed in international studies, and physical activity was a factor associated with the occurrence of this event in adolescents.