Hemodynamics and cardiac autonomic modulation after an acute concurrent exercise circuit in older individuals with pre- to established hypertension

OBJECTIVES: Few studies have investigated whether post-exercise hypotension (PEH) after concurrent exercise (CEX) is related to changes in cardiac output (Q) and systemic vascular resistance (SVR) in older individuals. We tested whether PEH after a single bout of CEX circuits performed in open-access facilities at the Third Age Academies (TAA) in Rio de Janeiro City (Brazil) would be concomitant with decreased Q and SVR in individuals aged ≥60 years with prehypertension. Moreover, we assessed autonomic modulation as a potential mechanism underlying PEH. METHODS: Fourteen individuals (age, 65.8±0.9 y; systolic/diastolic blood pressure [SBP/DBP], 132.4±12.1/72.8±10.8 mmHg; with half of the patients taking antihypertensive medications) had their blood pressure (BP), heart rate (HR), Q, SVR, HR variability (HRV), and spontaneous baroreflex sensitivity (BRS) recorded before and 50 min after CEX (40-min circuit, including seven stations of alternate aerobic/resistance exercises at 60-70% HR reserve) and non-exercise control (CONT) sessions. The study protocol was registered in a World Health Organization-accredited office (Trial registration RBR-7BWVPJ). RESULTS: SBP (Δ=−14.2±13.1 mmHg, p=0.0001), DBP (Δ=−5.2±8.2 mmHg, p= 0.04), Q (Δ=−2.2±1.5 L/min, p=0.0001), and BRS (Δ=−3.5±2.6 ms/mmHg; p=0.05) decreased after CEX as compared with the CONT session. By contrast, the HR increased (Δ=9.4±7.2 bpm, p<0.0001), and SVR remained stable throughout the postexercise period as compared with the CONT session (Δ=0.10±0.22 AU, p=0.14). We found no significant difference between the CEX and CONT with respect to the HRV indexes reflecting autonomic modulation. CONCLUSION: CEX induced PEH in the older individuals with prehypertension status. At least in the first 50 min, PEH occurred parallel to the decreased Q and increased HR, while SVR was not different. The changes in autonomic outflow appeared to be unrelated to the acute cardiac and hemodynamic responses.

Exercise Training Improves Heart Rate Recovery after Exercise in Hypertension

Abstract Aim: This study tested the hypothesis that: 1- the exercise training would improve the heart rate recovery (HRR) decline after maximal exercise test in hypertensive patients and; 2- the exercise training would normalize HRR decline when compared to normotensive individuals. Methods: Sixteen hypertensive patients were consecutively allocated into two groups: Exercise-trained (n = 9, 47±2 years) and untrained (n = 7, 42±3 years). An exercise-trained normotensive group (n = 11, 41±2 years) was also studied. Heart rate was evaluated by electrocardiogram. The autonomic function was evaluated based on heart rate changes on the first and the second min of recovery after the maximal exercise test. Exercise training consisted of three 60-minute exercise sessions/week for 4 months. Results: In hypertensive patients, exercise training significantly increased the HRR decline in the first (-19±2 vs. -34±3 bpm, P = 0.001) and second (-33±3 vs. -49±2 bpm, P = 0.006) minutes after the maximal exercise test. In addition, after exercise training, the initial differences in the HRR decline after exercise between hypertensive patients and normotensive individuals were no longer observed (first minute: -34±3 vs. -29±3 bpm, P = 0.52, and second minute: -49±2 vs. -47±4 bpm, P = 0.99). Conclusion: Hypertension causes a delay in HRR after the maximal exercise test yet the exercise training normalizes HRR during the post-exercise period in hypertensive patients.

Influência do nível de atividades físicas laborais, de lazer e locomoção na modulação autonômica cardíaca de repouso e na frequência cardíaca de recuperação / Influence of labor, leisure and locomotion physical activity level on resting cardiac autonomic modulation and in heart rate recovery

O objetivo deste estudo foi verificar a influência do nível das atividades laborais, de lazer e locomoção na modulação autonômica cardíaca de repouso e na freqüência cardíaca de recuperação. Métodos: Vinte jovens, saudáveis, do sexo masculino, que não praticavam exercício físico regular, foram divididos em dois grupos de acordo com o nível de atividade física habitual, obtido a partir do cálculo do escore total (ET), do questionário de Baecke: ‘menos ativos’ (n=10; 22,8±1,9 anos) e ‘mais ativos’ (n=10; 22,3±2,2 anos). Os registros dos intervalos R-R dos voluntários foram feitos em repouso, na posição supina por 15 minutos; durante o teste cardiopulmonar máximo e; por 5 minutos do período de recuperação. A variabilidade da freqüência cardíaca (VFC) foi analisada no domínio do tempo e da freqüência durante os últimos 5 minutos da coleta de repouso. Analisaram-se também índices de recuperação da freqüência cardíaca (FCrec). Resultados: Não houve diferença significativa entre os dois grupos em nenhum dos índices da VFC, assim como nos índices da FCrec. Conclusão: sugere-se que apenas atividades laborais, de lazer e te locomoção parecem não promover efeitos significativos na modulação autonômica cardíaca de repouso e na freqüência cardíaca de recuperação em jovens saudáveis. Nesse sentido, reforça-se a necessidade de atividades físicas sistematizadas e/ou aumento na intensidade das atividades laborais, de lazer e locomoção para promover adaptações autonômicas cardíacas.

Objective: The aim of this study was to investigate the labour, leisure and locomotion physical activities level on resting cardiac autonomic modulation and in heart rate recovery (HRR). Methods: 20 young healthy men, that didn’t practice physical exercise regularly, were divided into twogroups, according to their habitual physical activity level, obtained by the calculation of the total score, from Baecke’s questionnaire: ‘less actives’ (n=10; 22,8±1,9 years) and ‘more actives’ (n=10; 22,3±2,2years). The subjects’ R-R interval register was done by the supine resting position for 15 minutes; during the maximal effort text and; for 5 minutes from the recovery period. The heart rate variability (HRV) was analyzed in time and frequency domains, during the last 5 minutes of the resting register. It was alsoanalyzed HRR indexes. Results: There aren’t significant differences between the two groups in none of the HRV nor in the HRR indexes. Conclusion: In summary, it is suggested that only labour, leisure and locomotion activities seem not to provide significant effects on the resting cardiac autonomic modulation likewise in the HRR in healhy young men. Therefore, systematized physical activity or the rising of the intensity of labour, leisure and locomotionis are reinforced to provide positive cardiac autonomic adaptations.

Dieta hiperlipídica e ácido linoleico conjugado: efeitos nos lipídios séricos, peso e composição corporal de camundongos Apo E(-/-) exercitados / High-fat diet and conjugated linoleic acid: effects on serun lipids, weight and body composition of exercised Apo E(-/-) mice

Estratégias têm sido utilizadas para a prevenção de doenças cardiovasculares e aumento de peso. Sendo assim, muito tem sido especulado sobre alimentos funcionais e seus efeitos benéficos para a saúde humana e, em especial do Ácido Linoleico Conjugado (CLA). O objetivo foi avaliar os efeitos da dieta hiperlipídica e do CLA sobre os lipídios séricos, peso e composição corporal de camundongos Apolipoproteina E(-/-) (Apo E) exercitados. Camundongos knockout para Apo E foram alocados em quatro grupos/dieta: Normal (n=5), Hiperlipídica (n=6), Normal+CLA (n=5) e Hiperlipídica+CLA (n=6). Todos os grupos foram submetidos a um protocolo de corrida em esteira. Determinou-se o colesterol total, LDL-c e HDL-c no sangue, o peso e a composição corporal. Utilizou-se ANOVA e Tukey ao nível de significância de 5%. A dieta hiperlipídica elevou o colesterol total (Hiperlipídica=920,2±392,3 e Normal=382,3±207,9), LDL-c (Hiperlipídica=893,9±402,9 e Normal=339,9±204,8) e o peso corporal (Hiperlipídica=25,83±1,90 e Normal=339,9±204,8). O CLA reduziu a gordura (CLA=4,24±1,82 e Sem CLA=6,28±2,77) e elevou a proteína (CLA=23,02±1,04 e Sem CLA=21,45±1,04) na carcaça. Concluiu-se que a dieta hiperlipídica aumenta colesterol total e LDL-c e, o consumo de CLA diminui o gordura e aumenta a proteína na carcaça de camundongos Apo E(-/-) exercitados.

Strategies have been used for prevention of cardiovascular disease and weight gain. So much has been talked about functional foods and their beneficial effects on human health and, in particular conjugated linoleic acid. Evaluate the effects of high-fat diet and CLA on serum lipids, weight and body composition in Apolipoprotein E (-/-) mice (Apo E) exercised. Knockout mice ApoE were divided into four groups/diet: Normal (n=5), High-fat (n = 6), Normal+CLA (n=5) and High-fat+CLA (n=6). All groups underwent a protocol of treadmill running. Total cholesterol, LDL-c and HDL-c in the serum, weight and body composition were measured ANOVA followed by Tukey test were used (P<0.05). The high-fat diet elevated total cholesterol (High-fat=920,2± 392,3 and Normal=382,3±207,9), LDL-c (High fat=893,9±402,9 and Normal=339,9±204,8) and body weight (High-fat=25,83±1,90 and Normal= 339,9±204,8). The CLA reduced fat (CLA=4,24±1,82 and Without CLA=6,28±2,77) and increased the protein (CLA=23,02±1,04 and Without CLA=21,45±1,04) in the carcass. We conclude that the High-fat diet increases total cholesterol and LDL-C, and the consumption of the CLA reduces fat and increases the protein in the body composition of exercised ApoE(-/-) mice.