Aerobic Training Is Better Than Resistance Training on Cardiac Function and Autonomic Modulation in Female ob/ob Mice.

Objective: This study evaluated the effects of aerobic, resistance, and combined exercise training on cardiac function and autonomic modulation in female ob/ob mice. Methods: Four-week-old female wild type and obese (ob/ob) mice were divided into five groups (n = 8): control (WT), obese (OB) obese + aerobic training (OBA), obese + resistance training (OBR), and obese + combined training (OBC). The exercise training was performed on treadmill and/or ladder at 40-60% maximum test during 8 weeks. Cardiac function was measured using echo machine. Heart rate variability (HRV) was evaluated in the time and frequency domain. Results: OB group presented higher body weight gain (~600%), glycemia (~44%) and glucose intolerance (~150%), reduction of cardiac vagal modulation, evidenced by a lower RMMSD (~56%), total power and high frequency band, and a higher isovolumic relaxation time (IVRT) (~24%) in relation to the WT group. Aerobic and combined training led to a lower IVRT (OBA: ~14%; OBC: ~14%) and myocardial global index (OBA: ~37%; OBC: ~44%). The OBA group presented an increased in vagal indexes of HRV than the other ob/ob groups. A negative correlation was observed between the delta of aerobic exercise capacity and MPI (r = 0.45; p = 0.002) and exercise capacity and body weight gain (r = 0.39; p = 0.002). Conclusion: Only the obese females underwent to aerobic exercise training showed improvement in cardiac function and HRV. Moreover, the aerobic exercise capacity as well as a greater responsivity to aerobic exercise training is intimately associated with these improvements, reinforcing the importance of aerobic exercise training to this population.

Association between Diastolic Dysfunction with Inflammation and Oxidative Stress in Females ob/ob Mice.

Objective: To evaluate autonomic and cardiovascular function, as well as inflammatory and oxidative stress markers in ob/ob female mice. Methods: Metabolic parameters, cardiac function, arterial pressure (AP), autonomic, hormonal, inflammatory, and oxidative stress markers were evaluated in 12-weeks female wild-type (WT group) and ob/ob mice (OB group). Results: OB animals showed increased body weight, blood glucose, and triglyceride levels, along with glucose intolerance, when compared to WT animals. Ejection fraction (EF) and AP were similar between groups; however, the OB group presented diastolic dysfunction, as well as an impairment on myocardial performance index. Moreover, the OB group exhibited important autonomic dysfunction and baroreflex sensitivity impairment, when compared to WT group. OB group showed increased Angiotensin II levels in heart and renal tissues; decreased adiponectin and increased inflammatory markers in adipose tissue and spleen. Additionally, OB mice presented a higher damage to proteins and lipoperoxidation and lower activity of antioxidant enzymes in kidney and heart. Correlations were found between autonomic dysfunction with angiotensin II and inflammatory mediators, as well as between inflammation and oxidative stress. Conclusions: Our results showed that female adult ob/ob mice presented discrete diastolic dysfunction accompanied by autonomic disorder, which is associated with inflammation and oxidative stress in these animals.

Bicycling for transportation improves heart rate variability in young adults.

BACKGROUND: Physical activity has been considered an effective method to treat and prevent cardiovascular and metabolic disease. An important mechanism benefited by exercise training is the cardiovascular autonomic control, often impaired in cardiometabolic disease. Cycling used as a daily means of transport can be considered an interesting alternative to regular physical exercise practice. Therefore, this study intent to compare metabolic, hemodynamic and cardiovascular autonomic profiles of young adult men who were used to cycle for transportation (CT) with those considered insufficiently actives (IA). METHODS: Body composition, blood pressure, glucose, total cholesterol and triglycerides were evaluated at rest. Heart rate variability was analyzed in time and frequency domains. RESULTS: No differences were observed for body composition, blood pressure, glycemia nor lipids between groups. CT group presented resting bradycardia. Heart rate variability was increased in cyclists, as well as the parameters of parasympathetic modulation. Sympathetic modulation was reduced in CT group when compared to IA group. Additionally, positive correlations were observed between resting heart rate and RMSSD and heart rate variability, while heart rate variability was correlated with sympathovagal balance. CONCLUSIONS: Our results demonstrated that bicycling regularly used as a means of transport is able to improve cardiovascular autonomic modulation, thus reducing the risk of cardiovascular disease.

Exercise Training Prevents Cardiovascular Derangements Induced by Fructose Overload in Developing Rats.

The risks of chronic diseases associated with the increasing consumption of fructose-laden foods are amplified by the lack of regular physical activity and have become a serious public health issue worldwide. Moreover, childhood eating habits are strongly related to metabolic syndrome in adults. Thus, we aimed to investigate the preventive role of exercise training undertaken concurrently with a high fructose diet on cardiac function, hemodynamics, cardiovascular autonomic modulation and oxidative stress in male rats after weaning. Male Wistar rats were divided into 4 groups (n = 8/group): Sedentary control (SC), Trained control (TC), Sedentary Fructose (SF) and Trained Fructose (TF). Training was performed on a treadmill (8 weeks, 40-60% of maximum exercise test). Evaluations of cardiac function, hemodynamics, cardiovascular autonomic modulation and oxidative stress in plasma and in left ventricle (LV) were performed. Chronic fructose overload induced glucose intolerance and an increase in white adipose tissue (WAT) weight, in myocardial performance index (MPI) (SF:0.42±0.04 vs. SC:0.24±0.05) and in arterial pressure (SF:122±3 vs. SC:113±1 mmHg) associated with increased cardiac and vascular sympathetic modulation. Fructose also induced unfavorable changes in oxidative stress profile (plasmatic protein oxidation- SF:3.30±0.09 vs. SC:1.45±0.08 nmol/mg prot; and LV total antioxidant capacity (TRAP)- SF: 2.5±0.5 vs. SC:12.7±1.7 uM trolox). The TF group showed reduced WAT, glucose intolerance, MPI (0.35±0.04), arterial pressure (118±2mmHg), sympathetic modulation, plasmatic protein oxidation and increased TRAP when compared to SF group. Therefore, our findings indicate that cardiometabolic dysfunctions induced by fructose overload early in life may be prevented by moderate aerobic exercise training.

Heart rate variability in tennis players / Variabilidade da frequência cardíaca em tenistas / Variabilidad de la frecuencia cardíaca en tenistas

ABSTRACT Introduction Some studies suggest that playing tennis brings benefits for the anthropometric and metabolic profile of those who practice it, reducing the risk of mortality more significantly than other sports. In addition, changes in cardiovascular autonomic regulation have been highlighted as a common factor in the development of cardiometabolic disorders. Objective To evaluate and compare hemodynamic parameters and cardiovascular autonomic modulation among former tennis players who still play the sport (ET), adults who play recreational tennis (TR), and adults classified as sedentary (S). Methods Thirty-four men aged between 23 and 45 years participated in the study. They were divided into 3 groups: ET, TR and S. Anthropometric parameters and blood pressure were evaluated and the R-R interval was recorded to quantify the cardiac autonomic modulation at rest. Results Similar values were observed between groups for blood pressure, waist circumference and body mass index. The amount of moderate and vigorous physical activities of the ET group was higher than that of the TR group. The ET presented resting bradycardia associated with increased pulse interval (PI) variance and high-frequency PI, and a reduction in low-frequency PI compared to the other groups studied. Reduced cardiac sympathovagal balance was observed in the ET group (1.7 ± 0.1) and TR group (2.5 ± 0.2) compared to the S group (3.2 ± 0.2); however, this change was exacerbated in the ET group compared to the TR group. Conclusion The results suggest that playing tennis induces beneficial changes in cardiac autonomic modulation that appear to be intensified as the volume of physical activity increases, suggesting that this practice is beneficial in the management of cardiovascular risk. Level of Evidence II; Diagnostic Studies - Investigating a Diagnostic Test.

RESUMO Introdução Alguns estudos sugerem que a modalidade esportiva tênis traz benefícios aos perfis antropométrico e metabólico de seus praticantes, reduzindo o risco de mortalidade de forma mais significante que outras modalidades esportivas. Além disso, as alterações na regulação autonômica cardiovascular têm sido evidenciadas como fator comum no desenvolvimento de disfunções cardiometabólicas. Objetivo Avaliar e comparar parâmetros hemodinâmicos e de modulação autonômica cardiovascular entre ex-atletas de tênis que ainda praticam essa modalidade (ET), adultos que praticam tênis recreativo (TR) e adultos classificados como sedentários (S). Métodos Fizeram parte do estudo 34 homens com idade entre 23 e 45 anos, divididos em três grupos: ET, TR e S. Parâmetros antropométricos e pressão arterial foram avaliados e o intervalo R-R foi registrado para quantificar a modulação autonômica cardíaca em repouso. Resultado Foram observados valores semelhantes de pressão arterial, circunferência da cintura e índice de massa corporal entre os grupos estudados. A quantidade de atividades físicas moderadas e vigorosas realizadas pelo grupo ET foi maior que do grupo TR. O grupo ET apresentou bradicardia de repouso associada a aumento da variância do intervalo de pulso (IP), da banda de alta frequência do IP e redução da banda de baixa frequência do IP em relação ao demais grupos estudados. Foi observada redução do balanço simpato-vagal cardíaco nos grupos ET (1,7 ± 0,1) e TR (2,5 ± 0,2) em comparação com o grupo S (3,2 ± 0,2); no entanto, essa alteração foi exacerbada no grupo ET quando comparado ao grupo TR. Conclusão Os resultados permitem concluir que a prática do tênis induziu alterações benéficas na modulação autonômica cardíaca, as quais parecem ser intensificadas em função do volume de atividade física, sugerindo benefício desta prática no manejo de risco cardiovascular. Nível de Evidência II; Estudos diagnósticos - Investigação de um exame para diagnóstico.

RESUMEN Introducción Algunos estudios sugieren que la modalidad deportiva de tenis trae beneficios a los perfiles antropométrico y metabólico de sus practicantes, reduciendo el riesgo de mortalidad de forma más significante que otras modalidades deportivas. Además, los cambios en la regulación autonómica cardiovascular se han evidenciado como un factor común en el desarrollo de disfunciones cardiometabólicas. Objetivo Evaluar y comparar parámetros hemodinámicos y de la modulación autonómica cardiovascular entre ex atletas de tenis que aún practican esa modalidad (ET), adultos que practican tenis recreativo (TR) y adultos clasificados como sedentarios (S). Métodos Hicieron parte del estudio 34 varones de entre 23 y 45 años, divididos en tres grupos: ET, TR y S. Se evaluaron los parámetros antropométricos y la presión arterial, y el intervalo R-R fue registrado para cuantificar la modulación autonómica cardiaca de reposo. Resultados Se observaron valores similares de presión arterial, circunferencia de la cintura e índice de masa corporal entre los grupos estudiados. La cantidad de actividades físicas moderadas y vigorosas realizadas por el grupo ET fue mayor que del grupo TR. El grupo ET presentó bradicardia de reposo asociada a aumento de la varianza del intervalo de pulso (IP), de la banda de alta frecuencia del IP y la reducción de la banda de baja frecuencia del IP en relación a los demás grupos estudiados. Se observó una reducción del balance simpático-vagal cardiaco en los grupos ET (1,7 ± 0,1) y TR (2,5 ± 0,2) en comparación al grupo S (3,2 ± 0,2); sin embargo, esta alteración fue exacerbada en el grupo ET en comparación al grupo TR. Conclusión Los resultados permiten concluir que la práctica del tenis indujo cambios benéficos en la modulación autonómica cardiaca, los cuales parecen ser intensificados en función del volumen de actividad física, sugiriendo beneficio de esta práctica en el manejo de riesgo cardiovascular. Nivel de Evidencia II; Estudios de diagnósticos - Investigación de un examen para diagnóstico.

Sedentary lifestyle in adolescents is associated with impairment in autonomic cardiovascular modulation / Sedentarismo em adolescentes é associado ao comprometimento da modulação cardiovascular autonômica / Sedentarismo en adolescentes es asociado al compromiso de la modulación cardiovascular autonómica

ABSTRACT Introduction Regular physical exercise, or a more active lifestyle, are important to prevent cardiovascular diseases, reducing not only cardiovascular mortality but also promoting a reduction in the risk factors related to these diseases. Objective To assess the association between physical inactivity and heart rate variability (HRV) in adolescents. Methods This was a cross-sectional study of the Diagnostic Type with Level of Evidence II according to the Oxford table. One hundred and twenty-nine adolescents were evaluated, aged 15 and 17 years old, divided into four groups: male teenagers who were insufficiently active (IAM n = 28) or physically active (FAM n = 29), and female teenagers who were insufficiently active (IAF n = 42) or physically active (FAF n = 30). The level of physical activity was assessed by the IPAQ. The HRV was evaluated in the time and frequency domains. Results Reduced pulse interval variance was observed in the insufficiently active male or female groups (5089 ± 378 ms2 and 4335 ± 276 ms2 respectively) compared to the physically active groups (9106 ± 606 ms2 and 6182 ± 366 ms2 respectively). Moreover, the insufficiently active groups presented higher cardiac sympathetic/vagal balance values (0.81 ± 0.05 and 0.80 ± 0.05 respectively) compared to the physically active groups (0.63 ± 0.05 and 0.55 ± 0.05 respectively). Conclusion A physically active lifestyle was associated with better cardiovascular autonomic modulation in adolescents. Level of Evidence II; Diagnostic Studies - Investigating a Diagnostic Test.

RESUMO Introdução A prática regular de exercícios físicos ou o estilo de vida mais ativo são importantes na prevenção de doenças cardiovasculares, reduzindo não somente a mortalidade cardiovascular, mas também favorecendo a redução dos fatores de risco relacionados com essas doenças. Objetivo Avaliar a associação entre inatividade física e variabilidade da frequência cardíaca (VFC) em adolescentes. Métodos Este foi um estudo transversal do tipo Diagnóstico com Nível de Evidência II segundo a tabela de Oxford. Foram avaliados 129 adolescentes com idades entre 15 e 17 anos, divididos em quatro grupos: adolescentes insuficientemente ativos (IAM, n = 28) ou fisicamente ativos (FAM, n = 29) do sexo masculino e adolescentes, insuficientemente ativos (IAF, n = 42) ou fisicamente ativos do sexo feminino (FAF, n = 30). O nível de atividade física foi avaliado por meio do IPAQ. A VFC foi avaliada no domínio do tempo e da frequência. Resultados Nos adolescentes do sexo masculino e feminino, foram observados valores menores na variância do intervalo de pulso nos grupos insuficientemente ativos (5.089 ± 378 ms2 e 4.335 ± 276 ms2, respectivamente) quando comparados com os grupos fisicamente ativos (9.106 ± 606 ms2 e 6.182 ± 366 ms2, respectivamente). Além disso, os grupos insuficientemente ativos apresentaram maiores valores de balanço simpato-vagal cardíaco (0,81 ± 0,05 e 0,80 ± 0,05, respectivamente) comparados aos dos grupos fisicamente ativos (0,63 ± 0,05 e 0,55 ± 0,05, respectivamente). Conclusão A vida fisicamente ativa foi associada à melhor modulação cardiovascular autonômica em adolescentes. Nível de Evidência II; Estudos diagnósticos - Investigação de um exame para diagnóstico.

RESUMEN Introducción La práctica regular de ejercicios físicos o el estilo de vida más activo son importantes en la prevención de enfermedades cardiovasculares, reduciendo no sólo la mortalidad cardiovascular, sino también favoreciendo la reducción de los factores de riesgo relacionados con esas enfermedades. Objetivo Evaluar la asociación entre inactividad física y variabilidad de la frecuencia cardíaca (VFC) en adolescentes. Métodos Este fue un estudio transversal del tipo Diagnóstico con Nivel de Evidencia II según la tabla de Oxford. Se evaluaron 129 adolescentes con edades entre 15 y 17 años, divididos en cuatro grupos: adolescentes insuficientemente activos (IAM, n=28) o físicamente activos (FAM, n=29) del sexo masculino y adolescentes insuficientemente activos (IAF, n=42) o físicamente activos del sexo femenino (FAF, n=30). El nivel de actividad física fue evaluado a través del IPAQ. La VFC fue evaluada en el dominio del tiempo y de la frecuencia. Resultados Los adolescentes del sexo masculino y femenino insuficientemente activos presentaron valores menores en la varianza del intervalo de pulso (5.089 ± 378; y 4.335 ± 276 ms2, respectivamente) cuando se compararon con los grupos físicamente activos (9.106 ± 606 y 6.182 ± 366 ms2, respectivamente). Además, los grupos insuficientemente activos presentaron mayores valores del balance simpático-vagal cardíaco (0,81 ± 0,05 y 0,80 ± 0,05, respectivamente) comparados a los grupos físicamente activos (0,63 ± 0,05 y 0,55 ± 0,05, respectivamente). Conclusión La vida físicamente activa fue asociada a la mejor modulación cardiovascular autonómica en adolescentes. Nivel de Evidencia II; Estudios de diagnósticos - Investigación de un examen para diagnóstico.

Impairment on cardiovascular and autonomic adjustments to maximal isometric exercise tests in offspring of hypertensive parents.

The objective of the present study was to compare cardiovascular and autonomic responses to a mental stress test and to a maximal isometric exercise test between offspring of normotensive (ON, n = 10) and hypertensive parents (OH, n = 10). Subjects underwent a 3-min Stroop Color Word Test and a maximal isometric exercise test performed in an isokinetic dynamometer with continuous RR interval monitoring. At rest, arterial pressure and heart rate were similar between groups, but there was a significant reduction in total RR interval variance (ON: 5933 ± 493 vs. OH: 2967 ± 390 ms(2)) and an increase in low-high frequency components ratio of heart rate variability (ON: 2.3 ± 0.4 vs. OH: 4.6 ± 0.8) in OH group. In the first minute of the mental stress test and after both tests, the OH group presented increased heart rate as compared with the ON group. After both tests, only the ON group presented an increase in sympathetic component, thus reaching resting values similar to those of the OH group. Our data demonstrated increased resting cardiac sympathetic modulation in offspring of hypertensive parents at similar levels to that observed in offspring of normotensive parents after a mental stress test or a maximal isometric exercise test. Additionally, the exacerbated heart rate responses to these physiological tests in OH subjects may be associated with resting autonomic dysfunction, thus reinforcing these evaluations as important tools for detecting early dysfunctions in this genetically predisposed population.

Influência do número de séries nos ajustes cardiovasculares e autonômicos ao exercício resistido em homens fisicamente ativos / Influence of the number of sets in cardiovascular and autonomic adjustments to resistance exercise in physically active men

OBJETIVO: Avaliar a influência do número de séries nas alterações cardiovasculares e na variabilidade da frequência cardíaca (VFC) pós exercício resistido (ER) em homens fisicamente ativos. MÉTODOS: A amostra foi composta por 13 homens (27,38 ± 1,59 anos), normotensos, praticantes de musculação, submetidos a duas rotinas de musculação. A rotina 1 (R1) foi composta por duas séries de 10RM com intervalo de um minuto entre as séries e dois minutos entre os exercícios, e a rotina 2 (R2) foi similar a R1, no entanto, com três séries para cada exercício. A pressão arterial (PA), o intervalo de pulso (IP) e a VFC foram medidos em repouso e no período de recuperação (60 minutos) do ER. RESULTADOS: O ER induziu redução da PA sistólica pós-R1 (pré: 119,4 ± 1,70 versus pós: 110,8 ± 1,80 mmHg) e R2 (pré: 121,6 ± 2,20 versus pós: 110,3 ± 1,11 mmHg). Entretanto, a PA diastólica (pré: 71,2 ± 1,80 versus pós: 64,3 ± 2,40 mmHg) e a PA média (pré: 88,0 ± 1,60 versus pós: 80,7 ± 1,60 mmHg) reduziram somente após a R2, observando-se frequência cardíaca (FC) aumentada neste momento. A R2 promoveu redução da variância do IP na recuperação quando comparada à R1. Somente a R2 induziu aumento da banda de baixa frequência e redução da banda de alta frequência do IP em relação ao repouso. CONCLUSÃO: A redução da PA foi associada ao maior número de séries, mas não com redução da FC e/ou da modulação simpática cardíaca em praticantes de musculação.

OBJECTIVE: To evaluate the influence of the number of sets on cardiovascular changes and heart rate variability (HRV) in resistance exercise (RE) recovery period in physically active men. METHODS: The sample was composed of 13 (27.38 ± 1.59 years) normotensive men, practitioners of RE. Two RE routines were performed: routine 1 (R1) consisted of two sets of 10RM with 1 minute between sets and 2 minutes between exercises; and routine 2 (R2) was similar to R1; however, with three sets of each exercise. Blood pressure (BP), pulse interval (PI) and HRV were measured at rest and during recovery (60 minutes) from the RE. RESULTS: RE induced reduction in systolic BP after R1 (pre: 119.4 ± 1.70 vs. post: 110.8 ± 1.80 mmHg) and R2 (pre: 121.6 ± 2.20 vs. post: 110 3 ± 1.11 mmHg). However, diastolic BP (pre: 71.2 ± 1.80 vs. post: 64.3 ± 2.40 mmHg) and mean BP (pre: 88.0 ± 1.60 vs. post: 80.7 ± 1.60 mmHg) reduced only after the R2, and heart rate (HR) was increased at this time. The R2 promoted variance of PI reduction in the recovery when compared to the R1. Furthermore, only the R2 induced increase in low frequency band and reduction in high frequency band of PI compared to rest values. CONCLUSION: BP reduction was associated with higher number of sets, but not with reduction in HR and/or cardiac sympathetic modulation in RE practitioners.

História familiar positiva de diabetes altera a resposta cronotrópica ao exercício agudo / Positive diabetes family history alters chronotropic response to acute exercise

O objetivo do presente estudo foi verificar os efeitos de uma sessão de exercício aeróbio (SEA) no perfil metabólico e hemodinâmico em filhos de diabéticos do tipo II. Jovens saudáveis do sexo masculino foram divididos em dois grupos: filhos de diabéticos (FD, n = 7) e filhos de normoglicêmicos (FN, n = 7). Foram realizadas medidas metabólicas (triglicérides e glicemia) e cardiovasculares (pressão arterial, PA, e frequência cardíaca, FC) em repouso, durante e após a SEA. A SEA foi realizada em esteira ergométrica com duração de 30 minutos e intensidade progressiva. Os grupos apresentaram valores semelhantes em relação ao triglicérides, PA e FC em repouso. A glicemia de jejum do grupo FD foi maior em relação ao grupo FN (99 ± 2 versus 89 ± 2mg/dL). O grupo FD apresentou maior resposta cronotrópica no início da SEA quando comparado ao grupo FN (86 ± 4 versus 125 ± 8bpm), mas a FC foi semelhante entre os grupos nas demais intensidades. No quinto minuto de recuperação da SEA a FC foi maior no grupo FD comparado ao grupo FN (FN: 88 ± 3 versus FD: 97 ± 4bpm). A PA foi semelhante entre os grupos durante e após a SEA. Os resultados demonstram que filhos de diabéticos jovens já apresentam alterações metabólicas em repouso e resposta exacerbada da FC no início e nos primeiros minutos de recuperação da SEA, sugerindo um maior risco cardiovascular nessa população.

The aim of this study was to verify the effects of one aerobic exercise session (AES) on the metabolic and hemodynamic profile in diabetes type II offspring. Healthy young males were assigned into 2 groups: diabetic offspring (DO, n=7) and euglicemic offspring (EO, n=7). Metabolic (triglycerides and glucose levels) and cardiovascular (arterial pressure, AP, heart rate, HR) measures were realized before, during and after the AES. The AES was realized on a treadmill during 30 minutes, with progressive intensity. The groups showed similar triglycerides, AP and HR values at rest. The glucose level was higher in DO group when compared to the ED group (99±2 vs. 89±2 mg/dL). The DO group showed higher chronotropic response at the beginning of AES when compared to the EO group (86±4 vs. 125±8 bpm), however, the HR was similar between the groups at the other exercise intensities. At the fifth minute of the recovery, the HR was higher in the DO group when compared to the EO group (FN: 88 ± 3 vs FD: 97± 4 bpm). The AP was similar between groups during and after the AES. The results showed that young diabetic offspring presented metabolic alterations at rest, and exacerbated HR response at the beginning and in the recovery period of the AES, suggesting a higher cardiovascular risk in this population.

Mecanismos associados ao desenvolvimento das complicações do diabetes tipo 2 em camundongos fêmeas ob/ob: papel preventivo do treinamento físico dinâmico aeróbio, resistido ou combinado / Mechanisms associated with the development of complications of type 2 diabetes in ob/ob female mice: preventive role of dynamic aerobic resistance or combined exercise training

O objetivo do presente estudo foi avaliar o papel do treinamento físico aeróbio, resistido ou combinado (aeróbio+resistido) no desenvolvimento do diabetes tipo 2 analisando mecanismos associados às complicações no diabetes em camundongos fêmeas com deficiência na produção leptina (ob/ob). Para tanto, foram utilizadas camundongos fêmeas, inicialmente com 4 semanas de idade, divididas em 6 grupos: ob/ob sedentárias com 4 semanas de vida (OS-4), selvagens sedentárias (SS) ou ob/ob sedentárias (OS-12) acompanhadas até a 12ª semana de vida, ob/ob treinamento aeróbio (OA), ob/ob treinamento resistido (OR) e ob/ob treinamento combinado (OC). Os grupos treinados foram submetidos a 8 semanas de treinamento físico dinâmico aeróbio em esteira (50 a 60% da velocidade máxima do teste de esforço) ou resistido em escada (4060% da carga máxima) ou a associação dos dois treinos (combinado). Foram avaliados: peso corporal; glicose, triglicérides e colesterol total sanguíneos; pressão arterial (PA) e frequência cardíaca (FC); sensibilidade barorreflexa (SBR); modulação autonômica cardiovascular; marcadores inflamatórios e hormonais; e parâmetros de estresse oxidativo. Os animais obesos (OS-12) apresentaram aumento de peso corporal, tecido adiposo, de glicemia, de triglicérides e de intolerância à glicose quando comparado aos animais selvagens (SS). Adicionalmente, o grupo OS-12 apresentou piores resultados nos testes aeróbio e de força. Não observamos diferenças entre os grupos SS e OS-12 em relação a PA e FC, porém o grupo OS-12 apresentou diminuição da variabilidade da frequência cardíaca (VFC) (33 ± 4ms2) e da sensibilidade barorreflexa em relação ao grupo SS (VFC: 178 ± 19 ms2). O grupo OS-12 apresentou aumento de angiotensina 2 nos tecidos renal e cardíaco, diminuição da adiponectina e aumento de citocinas inflamatórias no tecido adiposo e no baço em relação ao grupo SS. Somado a isso, os animais obesos apresentam maior dano a proteínas e lipoperoxidação e diminuição das...

The aim of this study was to evaluate the role of aerobic, resistance or combined (aerobic + resistance) exercise training in the development of type 2 diabetes, analyzing mechanisms associated with diabetes complications in female mice with deficiency in leptin production (ob/ob). Female mice, initially with 4 weeks of age, were divided into 6 groups: ob/ob sedentary with 4 weeks of life (OS-4), sedentary wild type (SS) or ob/ob sedentary (OS-12) followed until 12 week life, ob/ob+aerobic training (OA), ob/ob+resistance training (OR) and ob/ob+combined training (OC). The trained groups were submitted to eight weeks of dynamic aerobic exercise training on a treadmill (50-60% of maximum stress test speed) or resistance exercise on a ladder (40-60% of the maximum load) or an association of these two trainings (combined). Body weight; glucose, triglycerides, and total blood cholesterol; blood pressure (BP) and heart rate (HR); baroreflex sensitivity (BRS); cardiovascular autonomic modulation; inflammatory and hormonal markers; and oxidative stress parameters were evaluated. Obese animals (OS-12) showed increased body and fat weight, blood glucose, triglyceride and glucose intolerance when compared to wild type animals (SS). Additionally, OS-12 group showed decreased capacity in aerobic and strength exercise tests. We did not observe differences between the SS and the OS-12 groups regarding BP and HR, however the OS-12 group showed reduced heart rate variability (HRV) (33 ± 4ms2) and baroreflex sensitivity when compared to the SS group (178 ± 19 ms2). The OS-12 group showed increased angiotensin 2 in kidney and heart tissues, decreased adiponectin and increased inflammatory cytokines in adipose tissue and in the spleen in relation to the SS group. Moreover, obese animals presented increased protein oxidation and lipid peroxidation and decreased antioxidant enzymes in kidney and heart tissues when compared to SS group. The comparison between the OS-4 and the OS-12...