Effects of 12 Weeks of Resistance Training on Cardiovascular Risk Factors in School Adolescents.

Background and objectives: The practice of physical exercise, especially resistance exercise, is important for the treatment and/or prevention of cardiovascular risk factors in adult individuals. However, there are few studies on its effects on adolescent individuals. Therefore, the aim of the present study was to evaluate the effects of applying a 12-week resistance training program on cardiovascular risk factors in adolescents. Materials and Methods: Thus, 122 adolescents aged 13-16 years of both genders participated in the study from school in the city of Lagarto, Sergipe (SE), Brazil, divided into two groups: Control Group (CG) and Group undergoing resistance training (RTG). Blood collection and anthropometric measurements were performed before and after the 12-week resistance training program (RTP). Results: After 12 weeks of the RTP in the adolescents, there was a reduction in the triglyceride variables (9.55%, p = 0.0286), Low-Density Lipoproteins (LDL) (5.42%, p = 0.0244), non-High-Density Lipoproteins (HDL) (5.40%, p = 0.0019), blood glucose (6.71%, p = 0.0040), systolic blood pressure (10.13%, p < 0.0001), as well as an increase in the body weight variable (1.73%, p = 0.0003). Conclusions: It was concluded that a 12-week RTP can prevent and/or alleviate the development of several chronic degenerative diseases in adulthood and that resistance training is important for maintaining the health of adolescents.

Metabolic, hemodynamic and structural adjustments to low intensity exercise training in a metabolic syndrome model.

BACKGROUND: The increase in fructose consumption is paralleled by a higher incidence of metabolic syndrome, and consequently, cardiovascular disease mortality. We examined the effects of 8 weeks of low intensity exercise training (LET) on metabolic, hemodynamic, ventricular and vascular morphological changes induced by fructose drinking in male rats. METHODS: Male Wistar rats were divided into (n = 8 each) control (C), sedentary fructose (F) and ET fructose (FT) groups. Fructose-drinking rats received D-fructose (100 g/l). FT rats were assigned to a treadmill training protocol at low intensity (30% of maximal running speed) during 1 h/day, 5 days/week for 8 weeks. Measurements of triglyceride concentrations, white adipose tissue (WAT) and glycemia were carried out together with insulin tolerance test to evaluate metabolic profile. Arterial pressure (AP) signals were directly recorded. Baroreflex sensitivity (BS) was evaluated by the tachycardic and bradycardic responses. Right atria, left ventricle (LV) and ascending aorta were prepared to morphoquantitative analysis. RESULTS: LET reduced WAT (-37.7%), triglyceride levels (-33%), systolic AP (-6%), heart weight/body weight (-20.5%), LV (-36%) and aortic (-76%) collagen fibers, aortic intima-media thickness and circumferential wall tension in FT when compared to F rats. Additionally, FT group presented improve of BS, numerical density of atrial natriuretic peptide granules (+42%) and LV capillaries (+25%), as well as the number of elastic lamellae in aorta compared with F group. CONCLUSIONS: Our data suggest that LET, a widely recommended practice, seems to be particularly effective for preventing metabolic, hemodynamic and morphological disorders triggered by MS.

Sildenafil: two decades of benefits or risks?

Sildenafil is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE-5). A patent was registered for this drug in 1990, which expired in 2010. Since expiration, the drug has been marketed under various trade names or as generic drugs. Numerous clinical trials have been conducted addressing the effectiveness of the drug for erectile dysfunction (ED) and its safety regarding the presence or absence of specific comorbidities. After over 20 years in the market, we need to ask: has the scientific community reached a general consensus as to the overall efficacy and safety of the drug? Can we firmly state that the benefits of the drug outweigh its risks? This review suggests that sildenafil is an effective and easily manageable treatment for erectile dysfunction, both in the absence and in the presence of comorbidities. After two decades of the emergence of sildenafil as a drug of choice for the treatment of ED (and the numerous studies and clinical trials undertaken during this time span), it is now possible to state that the benefits of the drug do outweigh the risks, and represent an significant improvement in the quality of life in men with ED.

Walking promotes metabolic and baroreflex sensitivity improvement in fructose-fed male rats.

The aim of this study was to investigate metabolic and cardiovascular responses to walking in fructose-fed rats. Male Wistar rats were divided into control (C), sedentary fructose (SF) and walking fructose (WF). Fructose-fed rats received D-fructose (100 g/l). WF rats walked on a treadmill at constant load (0.3 km/h) during 1 h/day, 5 days/week for 8 weeks. Measurements of triglyceride concentrations, adipose tissue and glycemia were carried out together with insulin tolerance test to evaluate metabolic profile. Arterial pressure (AP) signals were directly recorded. Baroreflex sensitivity (BR) was evaluated by the reflex tachycardia (TR) and bradycardia (BR) to AP changes. The results showed that walking decreased the adipose tissue (SF: 6.5 ± 0.4; WF: 2.8 ± 0.1; C: 3.0 ± 0.3 g), blood triglyceride levels (SF: 291 ± 6.5; WF: 150 ± 8.1; C: 103 ± 4.5 mg/dl) and increased insulin sensitivity (SF: 2.5 ± 0.2; WF: 3.3 ± 0.32; C: 4.8 ± 0.4 %/min). Baroreflex sensitivity was improved in the WF group expressed by BR (SF: 0.75 ± 0.10; WF: 1.18 ± 0.10; C: 1.5 ± 0.14 ms/mmHg) and TR (SF: 0.80 ± 0.12; WF: 1.21 ± 0.10; C: 1.35 ± 0.11 ms/mmHg), as well as when verified by the alpha index. Although the WF group showed decreased AP when compared with the SF group, the values still enhanced in relation to C rats (SF: 137 ± 2; WF: 129 ± 1; C: 115 ± 6 mmHg). Our findings allow a better understanding of the effects of walking, a low-intensity exercise training, on the hemodynamic and metabolic aspects of male rats with metabolic syndrome and indicate that walking seems to be particularly effective in treating metabolic disturbances in this model.

Low-dose enalapril reduces angiotensin II and attenuates diabetic-induced cardiac and autonomic dysfunctions.

Activation of renin-angiotensin system has been linked to cardiovascular and autonomic dysfunctions in diabetes. Experiments were performed to investigate the effects of angiotensin-converting enzyme inhibitor (ACEI), enalapril, on cardiac and autonomic functions in diabetic rats. Diabetes was induced by streptozotocin (50 mg/kg), and rats were treated with enalapril (1 mg · kg(-1) · d(-1)). After 30 days, evaluations were performed in control, diabetic, and enalapril-treated groups. Cardiac function was evaluated by echocardiography and through cannulation of the left ventricle (at baseline and in response to volume overload). Heart rate and systolic blood pressure variabilities were evaluated in the time and frequency domains. Streptozotocin rats had left ventricular systolic and diastolic dysfunctions, expressed by reduced ejection fraction and increased isovolumic relaxation time. The ACEI prevented these changes, improved diastolic cardiac responses to volume overload and total power of heart rate variability, reduced the ACE1 activity and protein expression and cardiac angiotensin (Ang) II levels, and increased angiotensin-converting enzyme 2 activity, despite unchanged blood pressure. Correlations were obtained between Ang II content with systolic and diastolic functions and heart rate variability. These findings provide evidence that the low-dose ACEI prevents autonomic and cardiac dysfunctions induced by diabetes without changing blood pressure and associated with reduced cardiac Ang II and increased angiotensin-converting enzyme 2 activity.

Strength Training Reduces Cardiac and Renal Oxidative Stress in Rats with Renovascular Hypertension. / Treino de Força Reduz Stress Oxidativo Cardíaco e Renal em Ratos com Hipertensão Renovascular.

BACKGROUND: Strength training has beneficial effects on kidney disease, in addition to helping improve antioxidant defenses in healthy animals. OBJECTIVE: To verify if strength training reduces oxidative damage to the heart and contralateral kidney caused by the renovascular hypertension induction surgery, as well as to evaluate alterations in the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) endogenous antioxidant enzymes. METHODS: Eighteen male rats were divided into three groups (n=6/group): sham, hypertensive, and trained hypertensive. The animals were induced to renovascular hypertension through left renal artery ligation. Strength training was initiated four weeks after the induction of renovascular hypertension, continued for a 12-weeks period, and was performed at 70% of 1RM. After the training period, the animals were euthanized and the right kidney and heart were removed for quantitation of hydroperoxides, malondialdehyde and sulfhydryl groups, which are markers of oxidative damage. In addition, the activity of SOD, CAT, and GPx antioxidant enzymes was also measured. The adopted significance level was 5% (p < 0.05). RESULTS: After strength training, a reduction in oxidative damage to lipids and proteins was observed, as could be seen by reducing hydroperoxides and total sulfhydryl levels, respectively. Furthermore, an increased activity of superoxide dismutase, catalase, and glutathione peroxidase antioxidant enzymes was observed. CONCLUSION: Strength training is able to potentially reduce oxidative damage by increasing the activity of antioxidant enzymes. (Arq Bras Cardiol. 2021; 116(1):4-11).

FUNDAMENTO: O treino de força tem efeitos benéficos em doenças renais, além de ajudar a melhorar a defesa antioxidante em animais saudáveis. OBJETIVO: Verificar se o treino de força reduz o dano oxidativo ao coração e rim contralateral para cirurgia de indução de hipertensão renovascular, bem como avaliar as alterações na atividade das enzimas antioxidantes endógenas superóxido dismutase (SOD), catalase (CAT) e glutationa peroxidase (GPx). MÉTODOS: Dezoito ratos machos foram divididos em três grupos (n=6/grupo): placebo, hipertenso e hipertenso treinado. Os animais foram induzidos a hipertensão renovascular através da ligação da artéria renal esquerda. O treino de força foi iniciado quatro semanas após a indução da hipertensão renovascular, teve 12 semanas de duração e foi realizada a 70% de 1RM. Depois do período de treino, os animais foram submetidos a eutanásia e o rim esquerdo e o coração foram retirados para realizar a quantificação de peróxidos de hidrogênio, malondialdeído e grupos sulfidrílicos, que são marcadores de danos oxidativos. Além disso, foram medidas as atividades das enzimas antioxidantes superóxido dismutase, catalase e glutationa peroxidase. O nível de significância adotado foi de 5% (p < 0,05). RESULTADOS: Depois do treino de força, houve redução de danos oxidativos a lipídios e proteínas, como pode-se observar pela redução de peróxidos de hidrogênio e níveis sulfidrílicos totais, respectivamente. Além disso, houve um aumento nas atividades das enzimas antioxidantes superóxido dismutase, catalase e glutationa peroxidase. CONCLUSÃO: O treino de força tem o potencial de reduzir danos oxidativos, aumentando a atividades de enzimas antioxidantes. (Arq Bras Cardiol. 2021; 116(1):4-11).

Hemodynamic and creatine kinase changes after a 12-week equipment-based Pilates training program in hypertensive women.

Exercise therapy is a conservative strategy to manage hypertension. The aim of this study was to investigate the effects of a 12-week equipment-based Pilates training program on the hemodynamics of medication-controlled hypertensive women. Forty-five women were classified into two groups: medication-controlled hypertensive (n = 30) or control (n = 15). To be eligible for the hypertensive group, participants had to have a clinical diagnosis of hypertension, be taking medication to control their blood pressure and not to have done any exercise activity in the previous three months. In the control group, the participants needed to have normal blood pressure levels and not to have done any exercise activity in the previous three months. All women participated in a 12-week equipment-based Pilates training program (2 × 60min sessions per week). Systolic and diastolic blood pressure (SBP, DBP), heart rate (HR) and creatine kinase levels (CK) were assessed before and after the program. SBP, DBP and heart rate were also assessed before and after each session. There was no statistically significant difference after Pilates training for systolic (normotensive MD 4.1, 95%CI -9.2 to 17.5, hypertensive MD 3.8, 95%CI -5.3 to 13.1) and diastolic (normotensive MD 5.8, 95%CI -2.0 to 13.7, hypertensive MD 4.0, 95%CI -4.3 to 12.4) blood pressure. Heart rate was reduced after Pilates training in both normotensive (MD 4.5, 95%CI 1.1 to 7.8) and medication-controlled hypertensive (MD 7.9, 95%CI 4.4 to 11.4) women. Creatine kinase activity was reduced after Pilates training in medication-controlled hypertensive women (p = 0.019). Blood pressure was not altered, but heart rate and creatinine kinase activity were reduced following 12 weeks of Equipment-based Pilates training.

Exercise improves cardiovascular control in a model of dislipidemia and menopause.

The present study investigated the effects of exercise training on arterial pressure, baroreflex sensitivity, cardiovascular autonomic control and metabolic parameters on female LDL-receptor knockout ovariectomized mice. Mice were divided into two groups: sedentary and trained. Trained group was submitted to an exercise training protocol. Blood cholesterol was measured. Arterial pressure (AP) signals were directly recorded in conscious mice. Baroreflex sensitivity was evaluated by tachycardic and bradycardic responses to AP changes. Cardiovascular autonomic modulation was measured in frequency (FFT) and time domains. Maximal exercise capacity was increased in trained as compared to sedentary group. Blood cholesterol was diminished in trained mice (191+/-8mg/dL) when compared to sedentary mice (250+/-9mg/dL, p<0.05). Mean AP and HR were reduced in trained group (101+/-3mmHg and 535+/-14bpm, p<0.05) when compared with sedentary group (125+/-3mmHg and 600+/-12bpm). Exercise training induced improvement in bradycardic reflex response in trained animals (-4.24+/-0.62bpm/mmHg) in relation to sedentary animals (-1.49+/-0.15bpm/mmHg, p<0.01); tachycardic reflex responses were similar between studied groups. Exercise training increased the variance (34+/-8 vs. 6.6+/-1.5ms(2) in sedentary, p<0.005) and the high-frequency band (HF) of the pulse interval (IP) (53+/-7% vs. 26+/-6% in sedentary, p<0.01). It is tempting to speculate that results of this experimental study might represent a rationale for this non-pharmacological intervention in the management of cardiovascular risk factors in dyslipidemic post-menopause women.

Noninvasive and invasive evaluation of cardiac dysfunction in experimental diabetes in rodents.

BACKGROUND: Because cardiomyopathy is the leading cause of death in diabetic patients, the determination of myocardial function in diabetes mellitus is essential. In the present study, we provide an integrated approach, using noninvasive echocardiography and invasive hemodynamics to assess early changes in myocardial function of diabetic rats. METHODS: Diabetes was induced by streptozotocin injection (STZ, 50 mg/kg). After 30 days, echocardiography (noninvasive) at rest and invasive left ventricular (LV) cannulation at rest, during and after volume overload, were performed in diabetic (D, N = 7) and control rats (C, N = 7). The Student t test was performed to compare metabolic and echocardiographic differences between groups at 30 days. ANOVA was used to compare LV invasive measurements, followed by the Student-Newman-Keuls test. Differences were considered significant at P < 0.05 for all tests. RESULTS: Diabetes impaired LV systolic function expressed by reduced fractional shortening, ejection fraction, and velocity of circumferential fiber shortening compared with that in the control group. The diabetic LV diastolic dysfunction was evidenced by diminished E-waves and increased A-waves and isovolumic relaxation time. The myocardial performance index was greater in diabetic compared with control rats, indicating impairment in diastolic and systolic function. The LV systolic pressure was reduced and the LV end-diastolic pressure was increased at rest in diabetic rats. The volume overload increased LVEDP in both groups, while LVEDP remained increased after volume overload only in diabetic rats. CONCLUSION: These results suggest that STZ-diabetes induces systolic and diastolic dysfunction at rest, and reduces the capacity for cardiac adjustment to volume overload. In addition, it was also demonstrated that rodent echocardiography can be a useful, clinically relevant tool for the study of initial diabetic cardiomyopathy manifestations in asymptomatic patients.

Treino de Força Reduz Stress Oxidativo Cardíaco e Renal em Ratos com Hipertensão Renovascular / Strength Training Reduces Cardiac and Renal Oxidative Stress in Rats with Renovascular Hypertension

Resumo Fundamento O treino de força tem efeitos benéficos em doenças renais, além de ajudar a melhorar a defesa antioxidante em animais saudáveis. Objetivo Verificar se o treino de força reduz o dano oxidativo ao coração e rim contralateral para cirurgia de indução de hipertensão renovascular, bem como avaliar as alterações na atividade das enzimas antioxidantes endógenas superóxido dismutase (SOD), catalase (CAT) e glutationa peroxidase (GPx). Métodos Dezoito ratos machos foram divididos em três grupos (n=6/grupo): placebo, hipertenso e hipertenso treinado. Os animais foram induzidos a hipertensão renovascular através da ligação da artéria renal esquerda. O treino de força foi iniciado quatro semanas após a indução da hipertensão renovascular, teve 12 semanas de duração e foi realizada a 70% de 1RM. Depois do período de treino, os animais foram submetidos a eutanásia e o rim esquerdo e o coração foram retirados para realizar a quantificação de peróxidos de hidrogênio, malondialdeído e grupos sulfidrílicos, que são marcadores de danos oxidativos. Além disso, foram medidas as atividades das enzimas antioxidantes superóxido dismutase, catalase e glutationa peroxidase. O nível de significância adotado foi de 5% (p < 0,05). Resultados Depois do treino de força, houve redução de danos oxidativos a lipídios e proteínas, como pode-se observar pela redução de peróxidos de hidrogênio e níveis sulfidrílicos totais, respectivamente. Além disso, houve um aumento nas atividades das enzimas antioxidantes superóxido dismutase, catalase e glutationa peroxidase. Conclusão O treino de força tem o potencial de reduzir danos oxidativos, aumentando a atividades de enzimas antioxidantes. (Arq Bras Cardiol. 2021; 116(1):4-11)

Abstract Background Strength training has beneficial effects on kidney disease, in addition to helping improve antioxidant defenses in healthy animals. Objective To verify if strength training reduces oxidative damage to the heart and contralateral kidney caused by the renovascular hypertension induction surgery, as well as to evaluate alterations in the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) endogenous antioxidant enzymes. Methods Eighteen male rats were divided into three groups (n=6/group): sham, hypertensive, and trained hypertensive. The animals were induced to renovascular hypertension through left renal artery ligation. Strength training was initiated four weeks after the induction of renovascular hypertension, continued for a 12-weeks period, and was performed at 70% of 1RM. After the training period, the animals were euthanized and the right kidney and heart were removed for quantitation of hydroperoxides, malondialdehyde and sulfhydryl groups, which are markers of oxidative damage. In addition, the activity of SOD, CAT, and GPx antioxidant enzymes was also measured. The adopted significance level was 5% (p < 0.05). Results After strength training, a reduction in oxidative damage to lipids and proteins was observed, as could be seen by reducing hydroperoxides and total sulfhydryl levels, respectively. Furthermore, an increased activity of superoxide dismutase, catalase, and glutathione peroxidase antioxidant enzymes was observed. Conclusion Strength training is able to potentially reduce oxidative damage by increasing the activity of antioxidant enzymes. (Arq Bras Cardiol. 2021; 116(1):4-11)

Influence of overweight on functional capacity of physically active older women / Influência do sobrepeso na capacidade funcional de mulheres idosas fisicamente ativas

Abstract Aging comprises a dynamic and progressive process, characterized by physiological and functional changes. Among these changes, increase in body fat is considered relevant, since it can leads to impaired physical fitness and augmented cardiometabolic risks. Considering this, the objective of this study was to evaluate the influence of overweight on functional capacity of physically active older women. A field survey was performed with 24 older women who practiced physical exercise. Participants were submitted to anamnesis, anthropometric measures (i.e., body mass and height); the Senior Fitness test; sit and reach flexibility test; and handgrip strength test. Pearson's correlation test and multivariate logistic regression were used to verify the association between overweight and functional capacity. It was observed that hip flexibility (R=-0.494, p=0.014) and flexibility of the lower limbs (i.e., sit and reach test) showed negative correlation with the body mass index (R=-0.446, p=0.02); and after the multivariate logistic regression, negative correlation of lower limbs flexibility (B=-0,035, p=0,014) and the body mass index was observed. Thus, higher the body mass index among participants, lower hip flexibility they presented.

Resumo O envelhecimento compreende um processo dinâmico e progressivo. Caracteriza-se por alterações fisiológicas e funcionais, sendo a modificação na composição corporal com o acréscimo de gordura corpórea considerada relevante, podendo ocasionar comprometimento da aptidão física e alterações cardiometabólicas. O objetivo deste estudo foi avaliar a influência do sobrepeso na capacidade funcional em idosas praticantes de exercício físico. Foi realizada uma pesquisa de campo correlacional com 24 idosas praticantes de exercício físico. Todas as idosas foram submetidas a anamnese, analise antropométrica com avaliação da massa corporal e estatura, capacidade funcional com a bateria de testes de Rikli e Jones (Sênior Fitness test), flexibilidade com o banco de Wells e força de prensão manual com o teste de preensão manual. Utilizou-se o teste de correlação de Pearson e a regressão logística multivariada pelo método Stepwise para verificar a associação entre sobrepeso e capacidade funcional. Observou-se que a flexibilidade de Quadril (R=-0,494, p=0,014) e a flexibilidade dos membros inferiores pelo banco de Wells (R=-0,446, p=0,02) apresentaram forte correlação negativa com o índice de massa corporal (IMC). Após a regressão logística multivariada, percebeu-se uma forte correlação negativa com a flexibilidade do quadril (B=-0,035, p=0,014). Assim, a flexibilidade do quadril entre as idosas ativas com sobrepeso reduziu com o aumento do IMC.

Hemodynamic response after concurrent cross exercise in hypertensive women / Respostas hemodinâmicas pós-exercício concorrente cruzado em mulheres hipertensas / Respuestas hemodinámicas post ejercicio concurrente cruzado en mujeres hipertensas

ABSTRACT Introduction: Systemic arterial hypertension is a disease that mainly affects women. Objective: This study aimed to verify the hypotensive effect and blood pressure reactivity in women submitted to a concurrent cross exercise (CC) session. Methods: Fifteen volunteers (54±3) performed aerobic exercise alternated with a series of weights exercises, for the analysis of blood pressure variation (by the oscillometric method) and pressure reactivity (by the Cold pressure test) before and after exercise. Results: The results demonstrated the occurrence of post-exercise hypotension in the systolic phase in the comparison between CC and C post-exercise (−11.65 mmHg). CC led to attenuation of 7mmHg and 4mmHg for SBP and DBP, respectively, in the blood pressure reactivity after one session. Conclusion: It is concluded that concurrent cross exercise ensures hypotension and positive reactivity of systolic blood pressure. Level of evidence II; Therapeutic studies-Investigating the results of treatment.

RESUMO Introdução: A hipertensão arterial sistêmica é uma doença que acomete, principalmente, mulheres. Objetivo: O presente estudo teve como objetivo verificar o efeito hipotensor e a reatividade da pressão arterial em mulheres submetidas a uma sessão de exercício concorrente cruzado (CC). Métodos: Quinze voluntárias (54±3) realizaram exercício aeróbico alternado com uma série de exercícios com peso para a análise da variação da pressão arterial (através do método oscilométrico) e reatividade pressórica (através do Cold pressure test) pré- e pós-exercício. Resultados: Os resultados demonstraram a ocorrência da hipotensão pós-exercício na fase sistólica na comparação entre CC e C pós- exercício (−11,65mmHg). O CC provocou a atenuação de 7 mmHg e 4 mmHg para PAS e PAD, respectivamente, na reatividade pressórica após uma sessão. Conclusão: Conclui-se que o exercício concorrente cruzado garante hipotensão e reatividade positiva da pressão arterial sistólica. Nível de evidência II; Estudos terapêuticos-Investigação dos resultados do tratamento.

RESUMEN Introducción: La hipertensión arterial sistémica es una enfermedad que afecta principalmente a las mujeres. Objetivo: El presente estudio tuvo como objetivo verificar el efecto hipotensor y la reactividad de la presión arterial en mujeres sometidas a una sesión de ejercicio concurrente cruzado (CC). Métodos: Quince voluntarias (54 ± 3) realizaron ejercicio aeróbico alternando con una serie de ejercicios con peso para el análisis de la variación de la presión arterial (a través del método oscilométrico) y reactividad presórica (a través del Cold Pressure Test) pre y post ejercicio. Resultados: Los resultados demostraron la ocurrencia de hipotensión post ejercicio en la fase sistólica en comparación entre CC y C post ejercicio (−11,65mmHg). El CC provocó la atenuación de 7 mmHg y 4 mmHg para PAS y PAD, respectivamente, en la reactividad presórica después de una sesión. Conclusión: Se concluye que el ejercicio concurrente cruzado garantiza hipotensión y reactividad positiva de la presión arterial sistólica. Nivel de evidencia II; Estudios terapéuticos-Investigación de los resultados del tratamiento.

Endothelium adjustments to acute resistance exercise are intensity-dependent in healthy animals.

AIMS: We evaluated the acute effects of different intensities of resistance exercise over endothelium-dependent vasodilatation, eNOSser1177 phosphorylation level and endothelial production of NO in superior mesenteric artery of healthy rats. MAIN METHODS: Groups: control (Ct), resistance exercise in the intensities of 30% (Ex30%), 50% (Ex50%) and 70% (Ex70%) of the maximal load established by the maximal repetition test (1RM). Exercise protocol: 15 sets of 10 repetitions. The rings of mesenteric artery were mounted in an isometric system or were prepared for further implementation of Western blot and DAF-FM techniques. KEY FINDINGS: The maximal response of the relaxation induced by insulin was not altered in the animals of the Ex30% group when compared to the Ct group. However, the animals of the Ex50% and Ex70% groups presented an increase in this response when compared to the Ct group. The eNOSser1177 phosphorylation levels showed an increase in Ex50% and Ex70% groups when compared to the Ct (1.6-fold and 3.3-fold, respectively). In the endothelial production of NO, it was observed that the Ex30% group did not show alteration in the NO production when compared to the Ct group. On the other hand, the animals exercised in the Ex50% and Ex70% groups showed increase in the NO synthesis when compared to the animals in the Ct group. SIGNIFICANCE: Our results suggest that the magnitude of these vascular endothelium adjustments is strongly related to the increase of the resistance exercise intensity from the intensity of 50% of 1 RM.

Influence of antihypertensive pharmacological treatment on the acute cardiovascular responses to the resistance exercise in hypertensive middle-aged women

Abstract Aim: To investigate the hypothesis that the resistance exercise (RE) may be safer if the blood pressure (BP) is properly controlled through antihypertensive pharmacological treatment in hypertensive middle-aged women. Methods: The final sample was comprised of 19 hypertensive women, with an average age of 58±5 years and a body mass index of 29±5 Kg/m2. They were divided into three groups: controlled (n=6), uncompensated (n=8), and untreated (n=5). The subjects from all groups were submitted to a test of maximal strength on extensor chair and held a session of RE (knee extension, 3x12 to 60% 1RM) and the cardiovascular response (BP and heart rate) was monitored continuously by photoplethysmography during exercise and until five minutes after exercise (recovery). Results: Systolic BP (SBP) and diastolic BP (DBP) responses were lower in the controlled group compared to the other groups (p<0.05). The heart rate was not different between groups, while the double product was lower in the controlled group compared to the untreated group (p<0.05). The SBP and DBP peaks were lower in the controlled group compared to the other groups (p<0.05). Conclusion: The BP increases significantly during RE when the hypertension is not controlled. Pharmacological control was shown to be effective in preventing the increase of BP during the performance of the RE.

Resistance exercise restores endothelial function and reduces blood pressure in type 1 diabetic rats.

BACKGROUND: Resistance exercise effects on cardiovascular parameters are not consistent. OBJECTIVES: The effects of resistance exercise on changes in blood glucose, blood pressure and vascular reactivity were evaluated in diabetic rats. METHODS: Wistar rats were divided into three groups: control group (n = 8); sedentary diabetic (n = 8); and trained diabetic (n = 8). Resistance exercise was carried out in a squat device for rats and consisted of three sets of ten repetitions with an intensity of 50%, three times per week, for eight weeks. Changes in vascular reactivity were evaluated in superior mesenteric artery rings. RESULTS: A significant reduction in the maximum response of acetylcholine-induced relaxation was observed in the sedentary diabetic group (78.1 ± 2%) and an increase in the trained diabetic group (95 ± 3%) without changing potency. In the presence of NG-nitro-L-arginine methyl ester, the acetylcholine-induced relaxation was significantly reduced in the control and trained diabetic groups, but not in the sedentary diabetic group. Furthermore, a significant increase (p < 0.05) in mean arterial blood pressure was observed in the sedentary diabetic group (104.9 ± 5 to 126.7 ± 5 mmHg) as compared to that in the control group. However, the trained diabetic group showed a significant decrease (p < 0.05) in the mean arterial blood pressure levels (126.7 ± 5 to 105.1 ± 4 mmHg) as compared to the sedentary diabetic group. CONCLUSIONS: Resistance exercise could restore endothelial function and prevent an increase in arterial blood pressure in type 1 diabetic rats.

Monosodium glutamate neonatal treatment induces cardiovascular autonomic function changes in rodents.

OBJECTIVES: The aim of this study was to evaluate cardiovascular autonomic function in a rodent obesity model induced by monosodium glutamate injections during the first seven days of life. METHOD: The animals were assigned to control (control, n = 10) and monosodium glutamate (monosodium glutamate, n = 13) groups. Thirty-three weeks after birth, arterial and venous catheters were implanted for arterial pressure measurements, drug administration, and blood sampling. Baroreflex sensitivity was evaluated according to the tachycardic and bradycardic responses induced by sodium nitroprusside and phenylephrine infusion, respectively. Sympathetic and vagal effects were determined by administering methylatropine and propranolol. RESULTS: Body weight, Lee index, and epididymal white adipose tissue values were higher in the monosodium glutamate group in comparison to the control group. The monosodium glutamate-treated rats displayed insulin resistance, as shown by a reduced glucose/insulin index (-62.5%), an increased area under the curve of total insulin secretion during glucose overload (39.3%), and basal hyperinsulinemia. The mean arterial pressure values were higher in the monosodium glutamate rats, whereas heart rate variability (>7 times), bradycardic responses (>4 times), and vagal (~38%) and sympathetic effects (~36%) were reduced as compared to the control group. CONCLUSION: Our results suggest that obesity induced by neonatal monosodium glutamate treatment impairs cardiac autonomic function and most likely contributes to increased arterial pressure and insulin resistance.

The importance of animal studies in exercise science

Abstract The validity and relevance of research with animals for the development of knowledge in Exercise Science have for long been discussed. Given the complexity of the biological systems, the use of animal models offers a significant contribution to uncover new findings about acute and chronic effects of exercise, particularly when these studies in humans have limitations and ethical implications. There have been notable findings using experimental animals either in basic sciences or in clinical studies involving physiology, pharmacology, genetic, biochemistry, urology, endocrinology and cancer. This article presents a brief review of scientific research using animal models with a focus on exercise training as an effective tool for the prophylaxis and treatment of different pathological processes, which are the basis of many concepts taught and used in undergraduate courses and graduate programs, as well as in new researches showed in scientific conference meetings in numerous areas of science.(AU)

Anabolic steroid associated to physical training induces deleterious cardiac effects.

PURPOSE: Cardiac aldosterone might be involved in the deleterious effects of nandrolone decanoate (ND) on the heart. Therefore, we investigated the involvement of cardiac aldosterone, by the pharmacological block of AT1 or mineralocorticoid receptors, on cardiac hypertrophy and fibrosis. METHODS: Male Wistar rats were randomized into eight groups (n = 14 per group): Control (C), nandrolone decanoate (ND), trained (T), trained ND (TND), ND + losartan (ND + L), trained ND + losartan (TND + L), ND + spironolactone (ND + S), and trained ND + spironolactone (TND + S). ND (10 mg·kg(-1)·wk(-1)) was administered during 10 wk of swimming training (five times per week). Losartan (20 mg·kg(-1)·d(-1)) and spironolactone (10 mg·kg(-1)·d(-1)) were administered in drinking water. RESULTS: Cardiac hypertrophy was increased 10% by using ND and 17% by ND plus training (P < 0.05). In both groups, there was an increase in the collagen volumetric fraction (CVF) and cardiac collagen type III expression (P < 0.05). The ND treatment increased left ventricle-angiotensin-converting enzyme I activity, AT1 receptor expression, aldosterone synthase (CYP11B2), and 11-ß hydroxysteroid dehydrogenase 2 (11ß-HSD2) gene expression and inflammatory markers, TGFß and osteopontin. Both losartan and spironolactone inhibited the increase of CVF and collagen type III. In addition, both treatments inhibited the increase in left ventricle-angiotensin-converting enzyme I activity, CYP11B2, 11ß-HSD2, TGFß, and osteopontin induced by the ND treatment. CONCLUSIONS: We believe this is the first study to show the effects of ND on cardiac aldosterone. Our results suggest that these effects may be associated to TGFß and osteopontin. Thus, we conclude that the cardiac aldosterone has an important role on the deleterious effects on the heart induced by ND.

Prevalência de sobrepeso e obesidade infantil em instituições de ensino: públicas vs. privadas / Prevalence of overweight and obesity in childhood in educational institutions: public vs private / Prevalencia de sobrepeso y obesidad en la infancia en las instituciones educativas: públicas vs. privadas

INTRODUÇÃO: dados epidemiológicos indicam que a obesidade infantil está aumentando na população brasileira e é apontada como um fator de risco para o desenvolvimento precoce de doenças crônicas. A obesidade tem sido caracterizada pelo aumento do tecido adiposo e do peso corporal. OBJETIVO: diagnosticar e comparar a prevalência de sobrepeso e obesidade em escolares da rede pública EPU e privada EPR. Além disso, foi feita uma correlação entre o IMC e o percentual de gordura corporal em crianças de ambos os sexos. MÉTODOS: foram avaliadas variáveis antropométricas IMC e DOC de meninos n = 91 e meninas n = 109 entre 8 e 10 anos de idade. Foi observada maior prevalência de sobrepeso em meninos 19,6% e meninas 25,5% da EPR em comparação com meninos 6,7% e meninas 8,1% da EPU. O nível de obesidade também foi maior em meninos 34,8% e meninas 31,9% da EPR quando comparado com meninos 6,7% e meninas 6,5% da EPU. Obteve-se correlação positiva entre as variáveis de IMC e percentual de gordura corporal de meninos r = 0,82 e meninas r = 0,85. RESULTADOS: os resultados sugerem que, apesar do aumento em todas as classes sociais, o sobrepeso e a obesidade mostram-se mais presentes naqueles com poder econômico maior, verificando-se, portanto, uma relação socioeconômica. Essa constatação pode levar a um estado de saúde mais próximo do polo negativo. CONCLUSÃO: a análise do IMC demonstrou ser um índice para determinação eficiente de sobrepeso e obesidade em crianças. .

INTRODUCTION: epidemiological data indicate that childhood obesity is increasing in Brazil and is identified as a risk factor for early development of chronic diseases. Obesity has been characterized by increased adipose tissue and body weight. OBJECTIVE: to diagnose and compare the prevalence of overweight and obesity in schoolchildren from public EPU and private EPR schools. METHODS: anthropometrics variables BMI and DOC [skin folds] were evaluated in boys n=91 and girls n=109 between 8 and 10 years old. There was a higher prevalence of overweight in boys 19.6% and girls 25.5% of the EPR compared to boys 6.7% and girls 8.1% of the EPU. The obesity level was higher in boys 34.8% and girls 31.9% of the EPR compared to boys 6.7% and girls 6.5% of the EPU. Positive correlation was obtained between the variables BMI and % body fat in boys r=0.82 and girls r=0.85. RESULTS: the results suggest that despite the increase in all social classes, overweight and obesity prevalence were more present in those with higher economic status, confirming therefore a socioeconomic relationship. This finding may lead to a health condition closest to the negative pole. CONCLUSION: the BMI analysis proved to be an index for efficient determination of overweight and obesity in children. .

INTRODUCCIÓN: los datos epidemiológicos indican que la obesidad infantil se ha incrementado en Brasil y que se identifica como un factor de riesgo para el desarrollo temprano de las enfermedades crónicas. La obesidad se ha caracterizado por un aumento de tejido adiposo y del peso corporal. OBJETIVO: diagnosticar y comparar la prevalencia de sobrepeso y obesidad en escolares de instituciones educativas públicas EPU y privadas EPR. Además, se encontró una correlación entre el IMC y el porcentaje de grasa corporal en niños de ambos sexos. MÉTODOS: se evaluaron las variables antropométricas IMC y DOC [pliegues cutáneos] de niños n = 91 y niñas n = 109 de entre 8 y 10 años de edad. Hubo una mayor prevalencia de sobrepeso en los niños 19,6% y niñas 25,5% de EPR en comparación con los niños 6,7% y niñas 8,1% de EPU. El nivel de obesidad fue mayor en los niños 34,8% y niñas 31,9% de EPR en comparación con los niños 6,7% y niñas 6,5% de EPU. Una correlación positiva se obtuvo entre las variables IMC y el porcentaje de grasa corporal de los niños r = 0,82 y niñas r = 0,85. RESULTADOS: los resultados sugieren que, a pesar del aumento en todas las clases sociales, el sobrepeso y la obesidad eran más presentes en aquellos con mayor poder económico, por lo tanto existe una relación socioeconómica. Este hecho puede dar lugar a un estado de salud más cerca de un polo negativo. CONCLUSIÓN: el análisis de IMC resultó ser un índice para la determinación eficiente de sobrepeso y obesidad en los niños. .

A brief review of chronic exercise intervention to prevent autonomic nervous system changes during the aging process.

The aging process is associated with alterations in the cardiovascular and autonomic nervous systems. Autonomic changes related to aging involve parasympathetic and sympathetic alterations leading to a higher incidence of cardiovascular disease morbidity and mortality. Several studies have suggested that physical exercise is effective in preventing deleterious changes. Chronic exercise in geriatrics seems to be associated with improvement in the cardiovascular system and seems to promote a healthy lifestyle. In this review, we address the major effects of aging on the autonomic nervous system in the context of cardiovascular control. We examine the use of chronic exercise to prevent cardiovascular changes during the aging process.