Water drinking during aerobic exercise improves the recovery of non-linear heart rate dynamics in coronary artery disease: crossover clinical trial.

Introduction: The post-exercise recovery is a period of vulnerability of the cardiovascular system in which autonomic nervous system plays a key role in cardiovascular deceleration. It is already known that individuals with coronary artery disease (CAD) are at greater risk due to delayed vagal reactivation in this period. Water ingestion has been studied as a strategy to improve autonomic recovery and mitigate the risks during recovery. However, the results are preliminary and need further confirmation. Therefore, our aim was to investigate the influence of individualized water drinking on the non-linear dynamics of heart rate during and after aerobic exercise in CAD subjects. Methods: 30 males with CAD were submitted to a control protocol composed of initial rest, warming up, treadmill exercise, and passive recovery (60 min). After 48 hours they performed the hydration protocol, composed of the same activities, however, with individualized water drinking proportional to the body mass lost in the control protocol. The non-linear dynamics of heart rate were assessed by indices of heart rate variability extracted from the recurrence plot, detrended fluctuation analysis, and symbolic analysis. Results and discussion: During exercise, the responses were physiological and similar in both protocols, indicating high sympathetic activity and reduced complexity. During recovery, the responses were also physiological, indicating the rise of parasympathetic activity and the return to a more complex state. However, during hydration protocol, the return to a more complex physiologic state occurred sooner and non-linear HRV indices returned to resting values between the 5th and 20th minutes of recovery. In contrast, during the control protocol, only a few indices returned to resting values within 60 minutes. Despite that, differences between protocols were not found. We conclude that the water drinking strategy accelerated the recovery of non-linear dynamics of heart rate in CAD subjects but did not influence responses during exercise. This is the first study to characterize the non-linear responses during and after exercise in CAD subjects.

Analysis of Barriers to Public and Private Cardiac Rehabilitation Programs in Patients with Low and High Adherence.

INTRODUCTION: Participants in cardiac rehabilitation programs have low adherence to their sessions, which makes extremely important to recognize the barriers that cause non-adherence, identifying whether the type of service and level of adherence influence these barriers. METHODS: This is a cross-sectional observational study, in which 220 individuals (66.80±11.59 years) of both genders who are members of public and private exercise-based cardiac rehabilitation programs participated. The volunteers were divided according to the level of adherence, considering patients with low adherence (PLA) those with < 70% of attendance and high adherence (PHA) those with > 70%. Then, initial evaluation, Cardiac Rehabilitation Barriers Scale, analysis of socioeconomic level, Hospital Anxiety and Depression Scale, and Mini-Mental State Examination were applied. RESULTS: Higher total barriers were found in PLA in the public service compared to PHA in the private service (P=0.023). In the subscale "perceived need", PHA in the public service showed higher values than PLA and PHA in the private service (P≤0.001). The "access" barrier was higher for PHA in the public service when compared to PHA in the private service (P=0.024). PHA in the public service exhibited a higher barrier regarding questions about distance, transportation problems, cost, and time constraints. CONCLUSION: The public program presents higher barriers in the questions and categories compared to the private program, mainly the PHA. Furthermore, there are differences in the profile of the participants regarding socioeconomic and anxiety levels, treatment time, ethnicity, and city where they live.

Physical load and heart rate behavior in workers in the slaughterhouse and meat packing industries / Carga física e comportamento da frequência cardíaca em trabalhadores de frigorífico

Abstract High physical overload during the workday and some conditions present in the workplace can generate several losses in the worker's health. The use of tools capable of identifying physical load (PL), such as heart rate (HR) analysis, is essential. The aim of the study was to evaluate the physical load and heart rate behavior of workers in the slaughterhouse. The cardiovascular load reached by two individuals was 12% and 24%. In relation to the PL rating, they fit as moderately heavy to heavy work. The HR, was higher at the end of the work when compared to the beginning. Furthermore, it was pointed out that the temperature, noise, and body mass index were above normality values. The physical workload was classified as moderately heavy to heavy. The limit HR was reached in some moments of the work by one of the workers and two of them reached higher HR values at the end of the work.

Resumo A elevada sobrecarga física durante a jornada de trabalho e algumas condições presentes no ambiente de trabalho podem gerar diversos prejuízos na saúde do trabalhador. A utilização de ferramentas capazes de identificar a carga física (CF), como a análise da frequência cardíaca (FC), é fundamental. O objetivo do estudo foi avaliar o comportamento da carga física e da frequência cardíaca dos trabalhadores de frigorífico. A carga cardiovascular alcançada por dois indivíduos foi de 12% e 24%. Em relação à classificação da CF, enquadram-se como trabalhos moderadamente pesados ​​a pesados. A FC, foi maior no final do trabalho quando comparado ao início. Além disso, apontou-se que a temperatura, o ruído e o índice de massa corporal estavam acima dos valores da normalidade. A CF de trabalho foi classificada como moderadamente pesada a pesada. A FC limite foi atingida em alguns momentos do trabalho por um dos trabalhadores e dois deles atingiram valores maiores de FC ao final do trabalho.

Analysis of Barriers to Public and Private Cardiac Rehabilitation Programs in Patients with Low and High Adherence

ABSTRACT Introduction: Participants in cardiac rehabilitation programs have low adherence to their sessions, which makes extremely important to recognize the barriers that cause non-adherence, identifying whether the type of service and level of adherence influence these barriers. Methods: This is a cross-sectional observational study, in which 220 individuals (66.80±11.59 years) of both genders who are members of public and private exercise-based cardiac rehabilitation programs participated. The volunteers were divided according to the level of adherence, considering patients with low adherence (PLA) those with < 70% of attendance and high adherence (PHA) those with > 70%. Then, initial evaluation, Cardiac Rehabilitation Barriers Scale, analysis of socioeconomic level, Hospital Anxiety and Depression Scale, and Mini-Mental State Examination were applied. Results: Higher total barriers were found in PLA in the public service compared to PHA in the private service (P=0.023). In the subscale "perceived need", PHA in the public service showed higher values than PLA and PHA in the private service (P≤0.001). The "access" barrier was higher for PHA in the public service when compared to PHA in the private service (P=0.024). PHA in the public service exhibited a higher barrier regarding questions about distance, transportation problems, cost, and time constraints. Conclusion: The public program presents higher barriers in the questions and categories compared to the private program, mainly the PHA. Furthermore, there are differences in the profile of the participants regarding socioeconomic and anxiety levels, treatment time, ethnicity, and city where they live.

Hydration Influence on the Autonomic Recovery of the Coronary Diseases Patient: Geometric Indices Analysis.

Purpose: To evaluate the recovery period of autonomic modulation, through geometric indices of heart rate variability (HRV), on coronary artery disease (CAD) patients submitted to a cardiovascular rehabilitation session (CR), associated with hydration. Methods: Thirty male participants of a CR program, diagnosed with CAD were submitted to the control (CP) and hydration protocol (HP) characterized by a CR session. Only during HP were the participants given 8 equal portions of water. The water amount was determined through the hydric loss measured at the CP. During the protocols, the heart rate was measured beat-by-beat at rest (5-10 minutes[M1]) and at recovery (0-5 minutes [M2], 5-10 minutes [M3], 15-20 minutes [M4], 25-30 minutes [M5], 40-45 minutes [M6], 55-60 minutes [M7]) for the HRV analysis, performed by the geometric indices: TINN, RRTRI, SD1, SD2 and SD1/SD2 ratio. Results: Statistically significant differences were observed between the protocols (SD1, pvalue = 0.022), moments (TINN, pvalue = 0.001; SD1, pvalue = 0.019; SD2, pvalue = 0.001; SD1/SD2, pvalue = 0.001) and moments vs. protocol interaction (SD1, pvalue = 0.019). The SD1 index pointed to acceleration of parasympathetic recovery in the first minutes after exercising (HP recovery after M3 [86.07 ± 32.31%] vs. CP recovery after M5[86.43 ± 24.56]) and increase in global variability (TINN-HP remained increased in longer, until M5 (M1 83.10 ± 55.76 ms to M5 116.82 ± 67.54 ms) vs. CP that remained increased for a short time, until M2 (M1 77.93 ± 68.56 ms to M2 134.82 ± 56.08 ms). Conclusions: In CAD patients, hydration promoted a more efficient recovery on parasympathetic autonomic modulation and increased the global HRV in the recovery period.

Autonomic responses to facial expression tasks in children with autism spectrum disorders: Cross-section study.

BACKGROUND: The autonomic nervous system has an influence on emotions and behavior modulation, however, the relationship between autonomic modulation impairment and the autism spectrum disorder (ASD) is yet to be fully described. AIMS: To evaluate the autonomic responses of children with and without ASD through the non-linear, and linear heart rate variability (HRV) measures, and assess the correlation between these responses, the severity and behavioral symptoms of autism. METHODS AND PROCEDURES: 27 children diagnosed with ASD (EG = experimental group) and 28 matching controls (CG = control group) were evaluated. The HRV was evaluated in 15 min sections at the following moments: I) Resting condition; II) During facial expression tasks; and III) Recovery. The severity and behavioral symptoms of autism were evaluated by the Childhood Autism Rating Scale (CARS) and Autistic Behaviors Checklist (ABC) scales. OUTCOMES AND RESULTS: The facial expression tasks influenced the activity of the autonomic nervous system in both groups, however the EG experienced more autonomic changes. These changes were mostly evidenced by the non-linear indices. Also, the CARS and ABC scales showed significant correlations with HRV indices. CONCLUSIONS AND IMPLICATIONS: Children with ASD presented an autonomic modulation impairment, mostly identified by the non-linear indices of HRV. Also, this autonomic impairment is associated with the severity and behavioral symptoms of autism.

Vagal reactivation after a cardiac rehabilitation session associated with hydration in coronary artery disease patients: crossover clinical trial.

This study aimed to investigate the hydration influence on the autonomic responses of coronary artery disease subjects in the immediate recovery period after a cardiovascular rehabilitation session, in view of the risks of a delayed autonomic recovery for this population. 28 males with coronary artery disease were submitted to: (I) Maximum effort test; (II) Control protocol (CP), composed by initial rest, warm-up, exercise and passive recovery; (III) Hydration protocol (HP) similar to CP, but with rehydration during exercise. The recovery was evaluated through the heart rate (HR) variability, HR recovery and by the rate of perceived exertion and recovery. The main results revealed that the vagal reactivation occurred at the first 30 s of recovery in HP and after the first minute in CP. A better behavior of the HR at the first minute of recovery was observed in HP. The rate of perceived exertion had a significant decrease in the first minute of recovery in HP, while in CP this occurred after the third minute. In conclusion, despite an anticipated vagal reactivation found at HP, these results should be analyzed with caution as there were no significant differences between protocols for all variables and the effect sizes were small.

Influence of the hydration on autonomic modulation and cardiorespiratory parameters of coronary heart disease patients submitted to a cardiovascular rehabilitation session: crossover clinical trial protocol

Abstract Aims: The influence of fluid replacement, realized during and after the exercise on individuals with coronary artery disease (CAD) remains poorly understood. To investigate the influence of hydration on cardiac autonomic modulation, cardiorespiratory parameters and perceived exertion and discommodity, of coronary heart patients submitted to cardiac rehabilitation (CR) session. Methods: This cross-over clinical trial, will recruit 31 adults with more than 45 years old, participants of a cardiovascular rehabilitation program, with CAD diagnosis. The participants will be submitted to an experimental protocol composed of three phases: I) Maximal stress test; II) Control protocol (CP); and III) Hydration protocol (HP). The CP and HP will consist of 10 min of rest in a supine position, 15 min of warming, 40 min of treadmill exercise, 5 min of cooling down and 60 min of rest in a supine position. In the HP, the participants will be hydrated with mineral water, based on the bodyweight reduction of the CP. The water intake will be divided into eight equal portions, offered during the treadmill exercise and recovery period. On CP and HP will be evaluated linear and nonlinear indices of heart rate variability, the heart rate, systolic blood pressure, diastolic blood pressure, respiratory rate, oxygen partial saturation, perceived exertion and discommodity on specifics moments. Conclusion: The results of this study will allow us to identify if the proposed protocol will be able to positively influence the outcomes and, consequently, if could be implement in the clinical practice.