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This study aimed to assess whether the blood glucose levels influence cardiac autonomic modulation under fasting and after carbohydrate overload conditions. Participants (n = 108) were separated into lower blood glucose and higher blood glucose groups, based on the median (90.5 mg·dL-1) of fasting glucose assessed. The SD2, SDNN, LF indices, and LF/HF increased, and HF decreased after dextrose overload compared with fasting (p < 0.05). Body mass (78.9 vs 69.7 kg), abdominal circumference (90.2 vs 82.2 cm), systolic (113 vs 108 mm Hg) and diastolic (72 vs 67 mm Hg) blood pressure were higher (p < 0.05) in the higher blood glucose group. Heart rate variability (HRV) indices (SD1: 21.0 vs 26.5; SD2: 76.8: vs 86.1; RMSSD: 28.7 vs 37.5; SDNN: 56.1 vs 62.5 ms; pNN50: 10.6 vs 18.9%, HF: 328.4 vs 506.0; LF: 982.8 vs 1259.0 ms2), and the area under the curve of these indices after dextrose overload were lower in the higher blood glucose group (p < 0.05). Additionally, glycemia after dextrose overload was correlated with HRV indices (ρ = -0.216 to -0.273, p < 0.05). Individuals with higher blood glucose, even in the normality range, showed impairment in the cardiac autonomic modulation both at fasting and after carbohydrate overload. Novelty: Higher fasting blood glucose impairs cardiac autonomic modulation. Carbohydrate overload impairs cardiac autonomic modulation.

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The aim of the present study was to analyze the effect of neuromuscular electrical stimulation (NMES) and photobiomodulation (PBMT) on the cardiovascular parameters, hemodynamic function, arterial baroreflex sensitivity (BRS), and autonomic balance (ANS) of rats with heart failure (HF). Male Wistar rats (220-290 g) were organized into five groups: Sham (n = 6), Control-HF (n = 5), NMES-HF (n = 6), PBMT-HF (n = 6), and NMES + PBMT-HF (n = 6). Myocardial infarction (MI) was induced by left coronary artery ligation. Animals were subjected to an eight-week NMES and PBMT protocol. Statistical analysis included the General Linear Model (GLM) followed by a Bonferroni post-hoc test. Rats of the NMES-HF group showed a higher MI area than the Control-HF (P = 0.003), PBMT-HF (P = 0.002), and NMES + PBMT-HF (P = 0.012) groups. NMES-HF and NMES + PBMT-HF showed higher pulmonary congestion (P = 0.004 and P = 0.02) and lower systolic pressure (P = 0.019 and P = 0.002) than the Sham group. NMES + PBMT-HF showed lower mean arterial pressure (P = 0.02) than the Sham group. Control-HF showed a higher heart rate than the NMES-HF and NMES + PBMT-HF (P = 0.017 and P = 0.013) groups. There was no difference in the BRS and ANS variables between groups. In conclusion, eight-week NMES isolated or associated with PBMT protocol reduced basal heart rate, systolic and mean arterial pressure, without influence on baroreflex sensibility and autonomic control, and no effect of PBMT was seen in rats with HF.

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INTRODUCTION: Repetitive and time sensitive demands of clothing workers has been associated with higher salivary cortisol levels that may reflect the stress experienced by the worker. OBJECTIVE: This trial evaluates if suboccipital fascial release (SFR) is associated with reduced salivary cortisol levels. METHODS: Randomized controlled trial with 40 workers, divided into: untreated group (UG, n = 15) and treated group (TG, n = 25). Both were removed from the work environment. The TG received the above technique and the UG remained lying at rest, both for five minutes. Salivary cortisol levels were measured by a commercial enzyme-linked immunosorbent assay (ELISA) kit. Statistical analysis of data distribution, intragroup and intergroups, were performed with α adjusted to 0.05. RESULTS: Pre / post intragroup analyses showed significant differences in cortisol levels in both groups, as well as intergroup analyses with lower values in favor of TG (p = 0.014). CONCLUSION: The reduction in salivary cortisol levels in TG suggests that SFR may be more effective than rest in reducing stress. Future studies with increased experimental rigor are necessary to confirm this conclusion. CLINICAL TRIAL REGISTRATION NUMBER: REBEC - RBR - 56yk9m.

INTRODUCTION: Les exigences aiguës imposées aux travailleurs de l'industrie du vêtement ont été associées à de fortes concentrations de cortisol salivaire pouvant traduire le stress vécu par ces travailleurs. OBJECTIF: Cet essai vise à savoir si le relâchement des fascias des muscles sous-occipitaux est associé à une réduction des concentrations de cortisol salivaire. MÉTHODOLOGIE: Essai comparatif avec répartition aléatoire mené auprès de 40 travailleurs répartis en deux groupes: groupe non traité (GNT, n = 15) et groupe traité (GT, n = 25). Les sujets des deux groupes ont été retirés de leur milieu de travail. La technique ci-haut mentionnée a été utilisée sur les sujets du GT alors que les sujets du GNT sont restés au repos: pour les deux groupes, l'intervention a duré cinq minutes. Les concentrations de cortisol salivaire ont été mesurées à l'aide d'une trousse pour dosage d'immunoabsorption par enzyme liée (ELISA) offerte dans le commerce. L'analyse statistique de la distribution des données intra-groupes et inter-groupes a été effectuée avec α ajusté à 0.05. RÉSULTATS: L'analyse des données prétraitement et post-traitement à l'intérieur des groupes a révélé des différences appréciables de concentration de cortisol dans les deux groupes, les analyses entre les groupes montrant des concentrations plus faibles dans le GT (p = 0.014). CONCLUSION: La réduction des concentrations de cortisol salivaire dans le GT semble indiquer que le relâchement des fascias de muscles sous-occipitaux peut être plus efficace que le repos pour réduire le stress. Il faut mener d'autres études expérimentales plus rigoureuses pour confirmer cette conclusion. NUMÉRO D'ENREGISTREMENT DE L'ESSAI CLINIQUE: REBEC ­ RBR ­ 56yk9m.

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The aim of the study was to investigate the effects of ingesting isoflavones associated with combined aerobic and resistance exercise training on heart rate variability (HRV) indices in postmenopausal women. Twenty-eight healthy postmenopausal women performed 10 weeks of combined exercise training associated with isoflavone (n = 16) or placebo (n = 12) supplementation. The RR intervals (RRi) were collected for 20 min using a heart rate monitor. Analysis of HRV was performed in time (mean squared difference of successive RRi (RMSSD), standard deviation of all normal RRi (SDNN), and percentage of adjacent RRi differing by more than 50 ms (pNN50)), frequency (low-frequency percentage (LF%), high-frequency percentage (HF%), and low-/high-frequency ratio (LF/HF)), and nonlinear domains (standard deviation of the instantaneous variability of the beat-to-beat interval (SD1), long-term variability of the continuous RRi (SD2), and their ratio (SD2/SD1)). Student's t test did not show differences between groups in any general baseline characteristic variables. The results of the generalized estimating equation tests did not demonstrate interaction or group effects for any HRV indices. However, the results reported time effects for mean RR (p < 0.001), RMSSD (p = 0.044), and SD1 (p = 0.044), with increases in these indices in response to exercise training. There were no time effects for LF%, HF%, LF/HF, SDNN, pNN50, SD2, or SD2/SD1. In conclusion, isoflavone supplementation did not promote additional effects on HRV indices of postmenopausal women subjected to 10 weeks of combined exercise training. Novelty Combined training improves heart rate variability in postmenopausal women. Isoflavone supplementation did not promote additional effects on heart rate variability in postmenopausal women.

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Angiotensin-(1-7) counterbalances angiotensin II cardiovascular effects. However, it has yet to be determined how cardiovascular autonomic modulation may be affected by chronic and acute elevation of Ang-(1-7). Hemodynamics and cardiovascular autonomic profile were evaluated in male Sprague-Dawley (SD) rats and transgenic rats (TGR) overexpressing Ang-(1-7) [TGR(A1-7)3292]. Blood pressure (BP) was directly measured while cardiovascular autonomic modulation was evaluated by spectral analysis. TGR received A-779 or vehicle and SD rats received Ang-(1-7) or vehicle and were monitored for 5 h after i.v. administration. In another set of experiments with TGR, A-779 was infused for 7 days using osmotic mini pumps. Although at baseline no differences were observed, acute administration of A-779 in TGR produced a marked long-lasting increase in BP accompanied by increased BP variability (BPV) and sympathetic modulation to the vessels. Likewise, chronic administration of A-779 with osmotic mini pumps in TGR increased heart rate, sympathovagal balance, BPV, and sympathetic modulation to the vessels. Administration of Ang-(1-7) to SD rats increased heart rate variability values in 88% accompanied by 8% of vagal modulation increase and 18% of mean BP reduction. These results show that both acute and chronic alteration in the Ang-(1-7)-Mas receptor axis may lead to important changes in the autonomic control of circulation, impacting either sympathetic and (or) parasympathetic systems.

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Peripheral sympathetic overdrive in young obese subjects contributes to further aggravation of insulin resistance, diabetes, and hypertension, thus inducing worsening clinical conditions in adulthood. Exercise training has been considered a strategy to repair obesity autonomic dysfunction, thereby reducing the cardiometabolic risk. Therefore, the aim of this study was to assess the effect of early exercise training, starting immediately after weaning, on cardiac autonomic control in diet-induced obese rats. Male Wistar rats (weaning) were divided into four groups: (i) a control group (n = 6); (ii) an exercise-trained control group (n = 6); (iii) a diet-induced obesity group (n = 6); and (iv) an exercise-trained diet-induced obesity group (n = 6). The development of obesity was induced by 9 weeks of palatable diet intake, and the training program was implemented in a motor-driven treadmill (5 times per week) during the same period. After this period, animals were submitted to vein and artery catheter implantation to assess cardiac autonomic balance by methylatropine (3 mg/kg) and propranolol (4 mg/kg) administration. Exercise training increased running performance in both groups (p < 0.05). Exercise training also prevented the increased resting heart rate in obese rats, which seemed to be related to cardiac pacemaker activity preservation (p < 0.05). Additionally, the training program preserved the pressure and bradycardia responses to autonomic blockade in obese rats (p < 0.05). An exercise program beginning at weaning age prevents cardiovascular dysfunction in obese rats, indicating that exercise training may be used as a nonpharmacological therapeutic strategy for the treatment of cardiometabolic diseases.

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