Effects of combined muscle power and endurance training with different volumes on functional and hemodynamic parameters in previously trained older adults.

BACKGROUND: To promote optimal neuromuscular and cardiovascular gains in older adults, it seems crucial to investigate the effects of different combined training volumes in this population. Thus, the present study aimed to compare the effects of combined muscle power training (MPT) and endurance training (ET) with different volumes on functional and hemodynamic parameters in previously trained older adults. METHODS: Twenty-five older adults were randomly assigned to either the lower-volume group (LVG; n = 13) or the higher-volume group (HVG; n = 12). In the LVG, participants performed 1 set of 6 repetitions for each exercise, followed by 10 min of walking exercise. In the HVG, participants performed 2 sets of 6 repetitions for each exercise, followed by 20 min of walking exercise. Lift from the ventral decubitus position (LPDV), timed up-and-go (TUG), systolic blood pressure (SBP), and diastolic blood pressure (DBP) were assessed before and after 8 weeks. RESULTS: Significant increases in LPDV test occurred in both groups after 8 weeks (p < 0.05). Additionally, significant improvements in TUG performance occurred in both groups from week 0 to week 8 (p < 0.05). However, no significant changes were observed between groups in functional parameters (p > 0.05). SBP and DBP remain unchanged (p > 0.05) in both groups over the experimental period. CONCLUSIONS: These findings indicate that lower-volume and higher-volume of combined MPT and ET promoted improvements in functional parameters. This study has an important practical application, as it indicates that regardless of the volume (lower or higher), comparable improvements are observed in functional parameters in previously trained older adults.

Phenotypes of mutations related to voltage-dependent sodium channels on children and adolescents.

Cardiac channelopathies are a heterogeneous group of inherited cardiac diseases that are associated with mutations in the genes that encode the expression of cardiac ion channels. In view of this, it can be mentioned that the main hereditary arrhythmias in children and adolescents, caused by dysfunction of the ion channels, are Brugada Syndrome (BrS) and Long QT Syndrome (LQTS). However, few studies address the physiological effects of these conditions on children and adolescents. Thus, the aim of this study is to describe the mutation phenotype related to voltage-gated sodium channels in children and adolescents. A search was performed in the literature of PubMed, Scielo, and Google scholar. The search was limited to articles written in the last 5 years, so articles published between 2014 and 2019 were included. Among 2196 studies identified through a systematic literature review, 30 studies related to the theme were identified for a complete review and after applying exclusion criteria, 4 articles were included in the results of this study. As the most frequently observed channelopathy, BrS was also more identified in children and adolescents, characterized by episodes of syncope or sudden cardiac death. LQTS shows clinical manifestations with a mild phenotype and good prognosis, although it is necessary to monitor and correct serum electrolyte disturbances to prevent ventricular arrhythmias and, consequently, sudden death in patients with the pathology. The aim of this study is to find the general phenotypes related to genetic mutations of voltage-gated sodium channels, in a population aged from 7- to 14-year-old.

Effect of treatment with carvacrol and aerobic training on cardiovascular function in spontaneously hypertensive rats.

NEW FINDINGS: What is the central question of this study? Can two non-drug therapies, carvacrol and aerobic physical training, together have additive effects on the reduction of cardiovascular risks and control of arterial hypertension? What is the main finding and its importance? The oral use of carvacrol (20 mg/kg/day) can control sustained hypertension in spontaneously hypertensive rats, and when this use is associated with aerobic physical training, there is a more pronounced effect on the reduction of blood pressure values, making these therapies an adjunct option in the drug treatment of hypertension. ABSTRACT: Systemic arterial hypertension is considered the foremost cardiovascular risk factor, and it is important to examine different therapies that help prevent and treat it, especially when associated with other cardiovascular risk factors. In this context, it is known that both carvacrol and aerobic physical training benefit the cardiovascular system. This study investigated the effects of treatment with carvacrol combined with aerobic exercise on hypertensive rats with cardiovascular risk parameters. We used an experimental design with six groups: normotensive control (Wistar rats); hypertensive control (spontaneously hypertensive rats, SHR); positive control rats treated with amlodipine (Aml-20 mg); rats treated with carvacrol (Carv-20 mg); rats trained with exercise (Exer); and rats treated with carvacrol and exercise (ExerCarv). The treatment lasted for 4 weeks, monitoring heart rate and systolic blood pressure (SBP). At the end of the treatment, vascular reactivity tests were performed in addition to biochemical measurements of urea, creatinine, aspartate aminotransferase, alanine aminotransferase, triglycerides, total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, very low density lipoprotein cholesterol, atherogenic indexes, relative heart weight and histopathological analysis of cardiac perivascular tissue. Significant reductions in SBP were observed after the training period, with the ExerCarv group showing a greater magnitude of reduction (∆SBP = 88 ± 10.0 mmHg, 42%). This group also experienced reductions in atherogenic indices and improvement in all analysed lipid parameters, with no differences observed in the Exer group. The findings indicated that the interaction between aerobic exercise and carvacrol offers a greater BP reduction. Exercise is particularly effective for controlling biochemical parameters of cardiovascular risk, regardless of carvacrol use.

The effect of family history of hypertension and polymorphism of the ACE gene (rs1799752) on cardiac autonomic modulation in adolescents.

This study aims to analyze the behaviour of cardiac autonomic modulation in adolescents with a family history of hypertension along with polymorphism of the ACE gene (rs1799752). The study involved 141 adolescents, with a mean age of 14.89, divided into the following six groups: offspring of normotensive parents (ONP): DD, DI and II; and offspring of hypertensive parents (OHP): DD, DI and II. Blood pressure, body composition, family history of hypertension, sleep disorder, and sexual maturation were assessed for the groups' characterization. Afterwards, an electrocardiogram was performed, and oral mucosal cells were collected to analyze heart rate variability and genotypic research of angiotensin-converting enzyme. The main finding of this study was the decrease of vagal action in group OHP (genotype DD) relative to group ONP (genotype II): LF (%), 54.25 ± 3.14 vs 39.33 ± 3.80; HF (%), 45.74 ± 3.14 vs 60.66 ± 3.80; LF/HF, 1.48 ± 0.23 vs 0.68 ± 0.19. The results also showed changes in the variable diastolic blood pressure (DBP) in OHP (genotype DI) to ONP (genotype II) groups: 72.99 ± 2.33 vs 63.27 ± 1.72; and OHP (genotype DI) to ONP (genotype DD) groups. Adolescents with genotype DD and a family history of arterial hypertension present chances in cardiac autonomic modulation, the cardiac parasympathetic modulation is lower in these adolescents in comparison to participants of ONP + II group.

Acute Effects of Resistance Exercise With Blood Flow Restriction in Elderly Women: A Pilot Study.

AIM: To compare the acute effects of two resistance exercise sessions with different partial blood flow restrictions (BFR) on hemodynamic parameters and cardiac autonomic modulation in older women with metabolic syndrome. METHODS: Thirty-nine older women (64.4 ± 4.5 years) were allocated into three groups: BFR0 = resistance exercise (20%, 1 maximum repetition [MR]) + 0% BFR; BFR60 = 20% 1 MR resistance exercise + 60% BFR; and BFR80 = 20% 1MR resistance exercise + 80% BFR. RESULTS: A reduction of 14 mmHg (BFR60 group) and 13 mmHg (BRF80 group) was observed 48 hr after the first exercise session, while vagal modulation was increased in the BRF60 group after 24 and 48 hr. CONCLUSION: A low-intensity resistance exercise session with 60% and 80% of BFR resulted in blood pressure (systolic, diastolic, and mean) reduction and positive changes on heart rate variability after 24 h of a RE session.

A Case-control Study of Exercise and Kidney Disease: Hemodialysis and Transplantation.

We aimed to analyze the effect of an exercise training program in autonomic modulation, and exercise tolerance of hemodialysis and kidney-transplanted patients. 4 groups of exercised and non-exercised patients undergoing hemodialysis and kidney-transplanted subjects had their biochemical tests, and heart rate variability evaluations analyzed. Also, sleep quality, anxiety and depression questionnaires were evaluated. Both exercised groups showed improvements in cardiovascular autonomic modulation, biochemical markers, and exercise tolerance after the exercise training program. The exercised kidney-transplanted patients group showed better improvements in cardiovascular autonomic modulation, biochemical markers, and exercise tolerance when compared to the exercised hemodialysis patients group. Both groups showed improvements in sleep quality, anxiety, and depression. The group of kidney-transplanted patients show better results in the cardiovascular autonomic modulation than subjects undergoing hemodialysis. However, the patients undergoing hemodialysis showed improvements in blood pressure, HDL, hemoglobin and phosphorus, changes not observed in the kidney-transplanted group. Exercise is beneficial for both hemodialysis and kidney-transplanted patients groups. However, exercise programs should be focused mainly in improving cardiovascular risk factors in the HD patients.

Hypertension and Exercise Training: Evidence from Clinical Studies.

Hypertension is a worldwide prevalent disease, mostly manifested as its primary ethiology, characterized by a chronic, multifactorial, asymptomatic, and usually incurable state. It is estimated that more than one billion of the world population is hypertensive. Also, hypertension is the main cause of the two most frequent causes of death worldwide: myocardial infarction and stroke. Due to the necessity of the cardiovascular system to manage chronically increased levels of blood pressure, hypertension causes severe alterations in multiple organs, as the heart, vessels, kidneys, eyes and brain, thus increasing the risk of health complications. The heart is the main target organ and suffers several adaptations to compensate the increased blood pressure levels; nevertheless, long-term adaptations without proper control are extremely harmful to cardiovascular health. On the other hand, hypertension is a modifiable risk factor and its adequate control is highly dependent on lifestyle. Pharmacological treatment is of great success when adherence is high. Several classes of antihypertensive drugs are prescribed and can effectively maintain blood pressure within acceptable levels. However, non-pharmacological methods, as diet and exercise training, can not only optimize the treatment but also prevent or postpone hypertension development as well as its complications, acting as important complements to the ideal control of elevated blood pressure, and bringing together benefits beyond blood pressure decrease, as a general health status improvement and increased quality of life. There is consistent evidence that regular exercise training promotes several benefits when properly prescribed and practised, acting as "medicine" for dozens of chronic diseases. The effects of exercise training in blood pressure levels and in its mechanisms of control are of clinical relevance and efficacy. This chapter will describe the classical and recent results on the beneficial effects of different modalities of exercise training in the cardiovascular system of human primary hypertension, focusing on the mechanisms influenced by exercise training which help to decrease blood pressure and improve the cardiovascular system.

Autonomic modulation analysis in active and sedentary kidney transplanted recipients.

Modulation of the autonomic nervous system on heart rate can be compromised in chronic kidney disease and may result in changes in the frequency and duration of the cardiac cycle. The aim of this study was to evaluate autonomic modulation in active and sedentary renal transplant recipients. Twenty renal-transplanted individuals were analyzed at the Centro de Prevenção de Doenças Renais (Kidney Disease Education Centre), in the academic hospital of Universidade Federal do Maranhão, and were divided into the active group (AG) and the sedentary group (SG). The AG comprised of six men and four women (age 43.10 ± 13.02) and was in regular concurrent training intervention for 8 weeks, while the SG was composed of three men and seven women (age 36.8 ± 9.26). Analysis of heart rate (HR) variability in time and frequency domain demonstrated that HR mean values in the SG and AG were 787.32 ± 79.60 and 870 ± 106.66 ms, respectively. Differences were observed in the time domain and frequency domain. The total index of low frequency and high frequency showed no differences between the SG and AG. Biochemical variables presented significantly lower levels after 8 weeks of training. Higher heart rate variability in the time domain and greater vagal modulation was observed in the AG. The AG ad greater vagal modulation when compared to the SG, with removal of the sympathetic and increased parasympathetic in the behaviour was confirmed by sympatho-vagal balance. The AG also presented significant improvements in the frequency domain.

Autonomic changes in young smokers: acute effects of inspiratory exercise.

PURPOSE: One of the most important consequences of smoking is the development of cardiovascular diseases. However, little is known about the early consequences of smoking and the acute effects of a single inspiratory muscle exercise session (IME). We evaluated the acute effects of an IME on cardiac parameters of young smokers. METHODS: Twelve nonsmokers (C) and fifteen smokers [S; 2.08 (1.0-3.2) pack-years] underwent an acute IME. We evaluated blood pressure (BP) and lactate, and we recorded RR interval for posterior analysis of heart rate variability (HRV), before and after IME. RESULTS: At baseline, systolic BP and HRV parameters in time and frequency domains were changed in S group in comparison with the C. Following IME, S group reduced systolic BP (-8 %), low frequency band (LF) (-21.4 %), LF/high frequency (HF) (-57 %), as well as increased RR variance (+105 %) and HF band. CONCLUSIONS: Our findings indicate that a single session of inspiratory muscle exercise was able to both reduce systolic BP and improve parasympathetic and sympathetic modulations in young smokers. The results of the current study highlight the importance of furthering research on this area to better elucidate the acute and chronic effects of inspiratory muscle training on early cardiovascular and pulmonary changes of cigarette smoking.

Ventricular and autonomic benefits of exercise training persist after detraining in infarcted rats.

We evaluate the effects of detraining (DT, for 1 month) on the left ventricular (LV) remodeling and function, hemodynamic and baroreflex sensitivity (BRS), as well as on mortality rate of infarcted (MI) rats after 3 months of exercise training (ET, 50-70 % of VO2max). Male Wistar rats were divided into five groups: control (C, n = 10), untrained-infarcted (UI, n = 15), trained-infarcted (TI, n = 12), untrained-infarcted plus 1 month (UI-1, n = 15) and detrained-infarcted 1 month (DI-1, n = 15). LV function was evaluated by echocardiography at the initial and final of the protocols. After following, ET and/or DT protocols, hemodynamic and BRS [by tachycardic (TR) and bradycardic (BR) responses] were assessed. TI group displayed increased VO2max in comparison with UI and DI-1 groups; however, DI-1 values remained increased compared to UI-1 group. MI area was reduced by ET and maintained after DT. Ejection fraction (TI = 60 ± 2 and DI-1 = 61 ± 2 % vs. UI = 41 ± 1 and UI-1 = 37 ± 3 %), E/A ratio (TI = 1.6 ± 0.1 and DI-1 = 1.9 ± 0.1 vs. UI = 2.9 ± 0.2 and UI-1 = 2.9 ± 0.3), TR (TI = 3.3 ± 0.3 and DI-1 = 3.3 ± 0.4 vs. UI = 1.7 ± 0.1 and UI-1 = 1.6 ± 0.1 bpm/mmHg) and BR (TI = -2.2 ± 0.1 and DI-1 = -2.0 ± 0.1 vs. UI = -1.3 ± 0.09 and UI-1 = -1.2 ± 0.09 bpm/mmHg) were improved by ET and maintained after DT in comparison with untrained rats. These changes resulted in mortality reduction in the TI (8 %) and DI-1 groups (13 %) compared with the UI (46 %) and UI-1 (53 %) groups. These findings indicate that ET is not only an effective tool in the management of cardiovascular and autonomic MI derangements, but also that these positive changes were maintained even after 1 month of DT in rats.

Impacts of covid-19 on sleep quality and autonomic function in elderly diabetic women.

AIM: to analyze the quality of sleep and cardiac autonomic modulation of elderly diabetic women in the post-covid-19 syndrome. METHODOLOGY: 41 elderly women, aged 60-75 years, with a diagnosis of Type 2 Diabetes Mellitus and who had covid-19 were included, divided into three groups: 14 in the Diabetes without covid-19 group (DG), 15 in the Diabetes with covid-19 group (CG), 12 in the Diabetes with covid-19 group who had Pulmonary Compromise (IG). Sleep quality was assessed using the Pittsburgh questionnaire, anamnesis, capillary blood glucose, blood pressure collection, anthropometry, resting electrocardiogram for 10 min for heart rate variability (HRV) analysis. Data were analyzed by 1-way ANOVA followed by Tukey-Kramer Multiple Comparisons Test, significance for p ≤ 0.05. RESULTS: there was no significant difference in age, blood glucose, blood pressure, and body composition between the groups. In the analysis of sleep quality, there was significance in the following indices: sleep duration, sleep efficiency, sleep disturbances, and daytime sleepiness. Further, there was a reduction in autonomic indices between CG vs. DG: VarRR (ms2), SDNN (ms), SD1 (ms), TINN (ms), HF-log (ms2), LF-log (ms2); and between IG vs. DG: VarRR (ms2), SDNN (ms), RMSSD (ms), SD1 (ms), SD2 (ms), and HF-log (ms2). CONCLUSION: it is suggestive that diabetic elderly women who had covid-19, with and without pulmonary impairment, have impaired sleep quality and interference on HRV with decreased parasympathetic autonomic modulation.

Reliability of the Heart Rate Variability Registered Through Polar Cardio Frequency Meter in Individuals With Chronic Low Back Pain.

Objective: The purpose of this study was to analyze the intra- and inter-examiner reliability of the analysis of heart rate variability (HRV) captured by a Polar cardio frequency meter in individuals with chronic nonspecific low back pain. Methods: The study included 35 individuals with nonspecific low back pain, both sexes, aged 18 to 45. We used a Polar V800 cardio frequency meter to capture HRV in individuals in different positions, and we calculated the reliability through the intraclass correlation coefficient (ICC). Results: Regarding intra-examiner reliability, we found excellent reliability of HRV analysis in the supine position (ICC ranging from 0.89 to 1.00) and in the standing position (ICC ranging from 0.95 to 0.99). In addition, for inter-examiner reliability, we found substantial to excellent reliability of the HRV analysis in the supine position (ICC ranging from 0.76 to 0.98) and moderate to excellent reliability in the standing position (ICC ranging from 0.73 to 0.99). Conclusion: The HRV analysis captured by a Polar cardio frequency meter presented adequate reliability when considering different times and different examiners.

Comparison of the autonomic nervous system dysfunction between different chronic spine disorders: neck pain versus low back pain.

OBJECTIVE: This study aims to compare heart rate variability (HRV) between patients with chronic neck pain and patients with chronic low back pain and to correlate the chronic pain variables with heart rate variability indices. METHODS: This is a cross-sectional study. We divided the sample into two groups: neck pain (n=30) and low back pain (n=30). We used the Numeric Pain Rating Scale, Neck Disability Index, Roland-Morris Disability Questionnaire, Pain-Related Catastrophizing Thoughts Scale, Tampa Scale of Kinesiophobia, and Pain Self-Efficacy Questionnaire. For heart rate variability analysis, we used the following indices: mean RR, standard deviation of all RR intervals, mean heart rate, root mean square differences of successive RR intervals, triangular index, triangular interpolation of the interval histogram, low-frequency band in arbitrary units and in absolute values, high-frequency band in arbitrary units and in absolute values, standard deviation of the instantaneous beat-to-beat variability (standard deviation 1), long-term standard deviation of continuous RR intervals (standard deviation 2), and Stress Index. We used Student's t-test for comparisons and Spearman's coefficient for correlations. RESULTS: We observe insignificant values in the differences between the groups. Disability and self-efficacy were correlated with heart rate variability only in patients with chronic neck pain, whereas catastrophizing and kinesiophobia showed greater correlations with heart rate variability in patients with chronic low back pain. CONCLUSIONS: Autonomic dysfunction of individuals with chronic neck pain, when compared to patients with chronic low back pain, does present insignificant differences.

Possible influences of vitamin D levels on sleep quality, depression, anxiety and physiological stress in patients with chronic obstructive pulmonary disease: a case control study.

This study aimed to evaluate the effect of vitamin D deficiency on sleep quality, depression, anxiety, and physiological stress in patients with chronic obstructive pulmonary disease (COPD). We screened for COPD patients with normal (NorVD) (n=24) and insufficient (InsVD) (n=7) vitamin D levels. The Pittsburgh sleep quality index (PSQI), the Beck anxiety inventory (BAI), the Beck depression inventory (BDI) and the Baevsky's stress index were used for the sleep and psychometric evaluation. The evaluation of sleep quality by PSQI showed that NorVD individuals had higher duration and quality of sleep when compared with the InsVD group. Additionally, the group InsVD presented higher risk of developing sleep quality (OR=6.20; 95% CI=1.334, 29.013; p=0.009). BDI was higher in the InsVD, and this group had a higher risk of developing moderate and severe depression (OR=3.37; 95% CI=0.895, 12.722; p=0.03). The stress index indicated higher values in the InsVD in relation to the NorVD group (InsVD=24±0.8 vs. NorVD=16±0.9), and the group InsVD showed higher risk of developing high and very high physiological stress (OR=7.70; 95% CI=1.351, 43.878; p=0.01). The stress and sleep quality effects were negatively correlated with vitamin D levels. Insufficient levels of vitamin D negatively affect sleep quality and psychometric variables.

Correlation of sleep quality and cardiac autonomic modulation in hemodialysis patients.

Objectives: Sleep disorders in patients on hemodialysis are frequent, but few studies correlate these disorders with autonomic dysfunction in these patients. This study aimed to verify whether clinical and laboratory variables and heart rate variability are associated with worse sleep quality verified by the Pittsburg subjective scale in patients on hemodialysis. Material and Methods: A cross-sectional study was performed on forty-eight patients. Epidemiological, clinical, and laboratory data were collected. After were performed by recording the heart rate variability and applied Pittsburg questionnaires, Beck anxiety index (BAI), and Beck depression index (BDI). The global PSQI score >5 indicates that a person is a poor sleeper, the patients were divided according to the scores in the Pittsburg questionnaire into good and poor sleepers and the differences between all variables were analyzed. Results: Forty-eight patients were evaluated and the prevalence of 68.7% (n=33) of poor sleep quality was verified. From the depression and anxiety questionnaires, it was found that only 18.7% (n=9) had criteria for depression. In the analysis of the sympathetic dysfunction parameters, it was found that in the group with good sleep quality in the frequency domain (HFm2) and the LFnu in the group with worse sleep quality. There was a positive correlation between sleep quality scores the anxiety and depression scores. It is also verified that the variables LFnu had a positive correlation with higher scores of quality of sleep and HFnu had a negative correlation with the highest scores of quality of sleep. Conclusion: In patients undergoing hemodialysis, the poorest quality of sleep is correlated with worse cardiac autonomic modulation as well as higher scores on the depression and anxiety scales.

Cardiac Autonomic Modulation is a Key Factor for High Blood Pressure in Adolescentes. / Modulação Autonômica Cardíaca é Fator Chave para Pressão Alta em Adolescentes.

BACKGROUND: The interest regarding hypertension among children and adolescents has increased since the blood pressure rating system was updated to be compared with the adult rating system, changing the terminology from "normal high" to "prehypertension". OBJECTIVE: This study aimed to analyze the association between cardiac autonomic modulation and pressure levels of adolescents. METHODS: 203 adolescents were grouped according to systolic blood pressure (SBP) and diastolic blood pressure (DBP). One group was characterized as prehypertension, and the other as normotensive. Anthropometric, cardiovascular and sleep quality characteristics were collected. Initially, the data were submitted to the Kolmogorov-Smirnov normality test. Continuous quantitative variables were analyzed using the unpaired Student t-test. For the analysis of categorical variables, a chi-square test was used. A logistic regression model was performed. The level of significance was set at p<0.05. The data were expressed as mean ± standard deviation and confidence interval. The R software was used for data analysis. The effect size was calculated using the Cohen's formula. RESULTS: The prehypertension group showed an increase in Shannon entropy and a decrease in total variance. Also, in the logistic regression model, adolescents in this group were 1.03 times more likely to have Shannon entropy's affected when SBP was adjusted for gender, sexual maturation, school time, age, waist circumference, and sleep quality. CONCLUSION: Our data show that autonomic modulation may play an important role in the development of elevated blood pressure in adolescents, when controlling for other factors, such as school time and sleep quality.

FUNDAMENTO: O interesse pela hipertensão em crianças e adolescentes aumentou desde a atualização do sistema de classificação da pressão arterial para comparar com o sistema de classificação dos adultos, alterando a terminologia de "normal alta" para "pré-hipertensão". OBJETIVO: O objetivo deste estudo foi analisar a associação da modulação autonômica cardíaca com os níveis pressóricos dos adolescentes. MÉTODOS: 203 adolescentes foram agrupados de acordo com a pressão arterial sistólica (PAS) e a pressão arterial diastólica (PAD). Um grupo foi caracterizado como pré-hipertensão, e o outro como normotenso. Foram coletadas características antropométricas, cardiovasculares e de qualidade do sono. Inicialmente, os dados foram submetidos ao teste de normalidade Kolmogorov-Smirnov . As variáveis quantitativas contínuas foram analisadas por meio do teste T de Student não pareado. Para análise das variáveis categóricas, foi utilizado o teste qui-quadrado. Um modelo de regressão logística foi realizado. O nível de significância estabelecido foi p<0,05. Os dados foram expressos como média ± desvio padrão e intervalo de confiança. O software R foi utilizado para análise dos dados. O tamanho do efeito foi calculado com a fórmula de Cohen. RESULTADOS: O grupo pré-hipertensão apresentou aumento da entropia de Shannon e diminuição da variância total. Além disso, no modelo de regressão logística, os adolescentes deste grupo tiveram 1,03 mais chances de ter a entropia de Shannon afetada quando a PAS foi ajustada ao gênero, maturação sexual, tempo escolar, idade, circunferência da cintura e qualidade do sono. CONCLUSÃO: Nossos dados mostram que a modulação autonômica pode desempenhar um papel importante no desenvolvimento da pressão arterial elevada em adolescentes ao controlar fatores como tempo escolar e qualidade do sono.

Cardiac autonomic modulation of adolescents with different levels of sleep quality.

Evaluate the cardiac autonomic modulation of adolescents with different levels of sleep quality. METHODS: Adolescents aged 11 to 17 years who presented themselves an explanation of the project with consent form signed by participated in the study. Anthropometric and hemodynamic data collected, and questionnaires. RESULTS: Analysis of the variables, age, systolic blood pressure, diastolic blood pressure, waist circumference, body fat and body mass index among the groups with good and poor sleep quality did not present a significant difference (p>0.05) in any paired characteristics. Time domain analysis indicated lower values in the vagal modulation with poor sleep quality. In the frequency domain, LF component increased and HF component decreased significantly in the group with poor sleep quality. There was also a statistical difference in the LF/HF analysis, the group with poor sleep quality presented an increase in this variable. CONCLUSION: The subjects with poor sleep quality present lower cardiac autonomic modulation.

Effect of obesity on sleep quality, anthropometric and autonomic parameters in adolescent.

OBJECTIVE: To compare the effects of obesity on sleep quality, the anthropometric and autonomic parameters of adolescents. MATERIAL AND METHODS: A cross-sectional study was carried out with adolescents aged 11 to 18, analyzing parameters such as BMI, sleep quality records, waist circumference, fat percentage, blood pressure and sexual maturation, in addition to autonomic cardiac function through the analysis of heart rate variability. RESULTS: The anthropometric parameters of waist circumference, percentage fat mass, were significantly higher in the group of obese adolescents. Sympathetic modulation in LF% was significantly higher in obesity. Parasympathetic modulation in HF% was significantly lower in obese than in eutrophic. CONCLUSION: Obese adolescents do not have poor sleep quality; there is no distinction between boys and girls regarding the analyzed variables; however, obesity alone was responsible for negatively influencing anthropometric parameters, as well as impairing the autonomic cardiac modulation.

Dynamic Resistance Training Improves Cardiac Autonomic Modulation and Oxidative Stress Parameters in Chronic Stroke Survivors: A Randomized Controlled Trial.

Stroke survivors are at substantial risk of recurrent cerebrovascular event or cardiovascular disease. Exercise training offers nonpharmacological treatment for these subjects; however, the execution of the traditional exercise protocols and adherence is constantly pointed out as obstacles. Based on these premises, the present study investigated the impact of an 8-week dynamic resistance training protocol with elastic bands on functional, hemodynamic, and cardiac autonomic modulation, oxidative stress markers, and plasma nitrite concentration in stroke survivors. Twenty-two patients with stroke were randomized into control group (CG, n = 11) or training group (TG, n = 11). Cardiac autonomic modulation, oxidative stress markers, plasma nitrite concentration, physical function and hemodynamic parameters were evaluated before and after 8 weeks. Results indicated that functional parameters (standing up from the sitting position (P = 0.011) and timed up and go (P = 0.042)) were significantly improved in TG. Although not statistically different, both systolic blood pressure (Δ = -10.41 mmHg) and diastolic blood pressure (Δ = -8.16 mmHg) were reduced in TG when compared to CG. Additionally, cardiac autonomic modulation (sympathovagal balance-LF/HF ratio) and superoxide dismutase were improved, while thiobarbituric acid reactive substances and carbonyl levels were reduced in TG when compared to the CG subjects. In conclusion, our findings support the hypothesis that dynamic resistance training with elastic bands may improve physical function, hemodynamic parameters, autonomic modulation, and oxidative stress markers in stroke survivors. These positive changes would be associated with a reduced risk of a recurrent stroke or cardiac event in these subjects.

Inspiratory muscle training improves autonomic modulation and exercise tolerance in chronic obstructive pulmonary disease subjects: A randomized-controlled trial.

OBJECTIVES: We aimed to evaluate the effect a regular inspiratory muscle training program on autonomic modulation measured by heart rate variability, exercise capacity and respiratory function in chronic obstructive pulmonary disease subjects (COPD). DESIGN: Single-center controlled study, with balanced randomization (1:1 for two arms). SETTING: A COPD reference hospital localized in Sao Luís, Brazil. PARTICIPANTS: 22 COPD subjects joined the study. INTERVENTIONS: Three times a week for four weeks inspiratory muscle training (IMT) at 30% of PImax. MAIN OUTCOME MEASURES: Pulmonary capacities and inspiratory pressure, total six-minute walk test and, cardiac autonomic modulation. RESULTS: The intervention group showed improvements in the cardiac autonomic modulation, with increased vagal modulation (total variability and HF [ms2; adjusted p < 0.05]); increased expiratory and inspiratory capacities and, increased distance in the 6-min walk test. CONCLUSION: 12 weeks of IMT at 30% of the maximal inspiratory pressure increased cardiac autonomic modulation, expiratory and inspiratory and exercise capacity in COPD subjects.