The Acute Effects of 2 Different Intensities of Resistance Exercise on Autonomic Function in Heart Failure Patients: A Randomized Controlled Trial.

BACKGROUND: Although a wide spectrum of resistance exercise intensities was recommended in the guidelines, none of them investigated the acute effects of different intensities of the resistance exercise on cardiac autonomic function in patients with chronic heart failure. This study aimed to investigate the acute effects of the low and high intensities of the resistance exercise on heart rate variability in chronic heart failure. METHODS: This randomized controlled trial was performed between October 2019 and December 2020. Fifty-seven patients with chronic heart failure (New York Heart Association class II and class III) underwent hemodynamic, functional capacity, and heart rate variability (time and frequency domains) assessments. They were randomly divided into R1, R2, and control groups. The intervention consisted of performing a short aerobic exercise including 15 minutes of walking at an intensity of 50% reserved heart rate for all 3 groups and additional resistance exercise with the intensity of 50% 1-repetition maximum and 75% 1-repetition maximum for R1 and R2 groups, respectively. RESULTS: The standard deviation of normal to normal intervals and standard deviation of average NN intervals became significantly lower in R2 (P =.031), and both high-frequency power and low-frequency power were significantly higher in R1 (P =.039 and P =.004, respectively) after the intervention. No significant changes were observed in the control group. Between-group changes were not significant for hemodynamics and functional capacity after treatment. The between-group comparison demonstrated a significant increase in root mean square of successive differences of the NN intervals in R1 in comparison to the control (P =.035). CONCLUSIONS: These findings indicate that resistance exercise in 50% 1-repetition maximum in comparison to 75% 1-repetition maximum had more favorable effects on the heart rate variability in chronic heart failure.

Validation study of the Persian version of the subjective exercise experiences scale (SEES) in Iranian adult individuals.

BACKGROUND: Subjective exercise experiences scale (SEES) is a 12-item questionnaire assessing global psychological responses to exercise, with three constructs including positive well-Being (PWB), psychological distress (PD), and fatigue (FAT). The present study aimed to assess the reliability and validity of the SEES questionnaire in the Iranian population. METHOD: This cross-sectional psychometric study was conducted on 138 adults immediately after 30 min of walking. The internal consistency of the questionnaire was evaluated with Cronbach's alpha coefficient. To assess the test-retest reliability, 38 of the participants were requested to fill in the questionnaire again after a week. The test-retest reliability was analyzed using the intra-class correlation coefficient (ICC). The concurrent validity was examined through the correlation matrix between the domains of SEES and SF12. Principle component analysis was performed to determine the factor loading of the measured variables. IBM SPSS statistics 24 was used for all calculations. RESULTS: Cronbach's alpha was 0.82, 0.82, and 0.81 for the PWB, PD, and FAT, respectively. The ICC value was acceptable for all subscales (ICC for PWB, PD, and FAT were 0.83, 0.88, and 0.74 respectively). There was a weak to moderate correlation between the SEES and SF-12 subclasses. Factor analysis confirmed the three-factor structure of the instrument, explaining 67.21% of the observed variance. Item 3 didn't fit in well with the three constructs and was deleted from the Persian version of the SEES. CONCLUSIONS: The Persian version of the SEES is a valid and reliable instrument to evaluate the psychological response to the exercise stimulus.

Effects of resistance added on aerobic training on autonomic function in cardiac patients.

OBJECTIVE: Autonomic imbalance in patients with chronic heart failure (CHF) and cardiovascular diseases (CVD) is characterized by reduced parasympathetic and enhanced sympathetic activity. Aerobic exercise improves autonomic function in patients with CHF and CVD. However, little is known about the effects of resistance training (RT) on cardiac autonomic function. Therefore, we aimed to investigate the effects of RT added on aerobic training on autonomic function in patients with CHF and CVD. DATA SOURCES: The relevant clinical trials were searched in PubMed, Physiotherapy evidence Database (PEDro, Science Direct and Google Scholar databases using the following keywords, "resistance or strength training", "chronic heart failure", "coronary artery disease", "myocardial infarction", "hypertension", "cardiovascular disease", "heart rate variability (HRV)", "heart rate recovery (HRR)", "muscle sympathetic nerve activity (MSNA)", and "autonomic function". DATA SYNTHESIS: Twelve articles with 323 subjects were eligible to be evaluated. The outcome measures included HRV, HRR, and MSNA. There were seven studies on CHF, two on CAD, and three studies on hypertension. Meta-analysis of all the studies showed that combined RT and aerobic training decreased MSNA significantly in patients with CHF and CAD (mean difference: -3.796; CI: -6.779 to 0.813; p=0.013; I2 =93.5%). No study evaluated the effects of RT or combined training on HRR. CONCLUSION: We could not find sufficient data about the effects of RT alone on HRV and HRR, but the results showed that combined RT and aerobic training improved MSNA in patients with CHF and CAD, significantly. Further studies with similar methodological principles on the same patient population are needed.

Effects of Sodium Concentration and Dialysate Temperature Changes on Blood Pressure in Hemodialysis Patients: A Randomized, Triple-Blind Crossover Clinical Trial.

The present study investigated the effects of different temperatures and sodium dialysate concentration on blood pressure in hemodialysis patients. Following Williams' design, hemodialysis patients were randomly assigned into four dialysis modes. Dialysate temperature was set at 37°C for modes A and C and, 35°C for modes B and D. Sodium concentration was set at 138 mmol/L in modes A and B, while it changed from 150 mmol/L to 138 mmol/L in modes C and D. Using analysis of variance for repeated measures, the mean values of systolic and diastolic blood pressure were investigated. The mean values of systolic and diastolic blood pressure in modes C and D had a significant difference with the values in mode A. The mean values of systolic and diastolic blood pressure in patients dialyzed with mode B had a significant difference with the values in those dialyzed with mode D. Moreover, there were significant differences in the incidence of hypotension between A and other modes and between B and modes C and D, but this difference was not significant between modes C and D. In order to reduce intradialytic blood pressure fluctuations and hypotension, the nursing staff are recommended to gradually reduce dialysate sodium concentration.

Effects of a comprehensive cardiac rehabilitation program on quality of life in patients with coronary artery disease.

BACKGROUND: Health-related quality of life is an important factor to evaluate effects of different interventions in cardiovascular diseases. Improvement in quality of life (QOL) is an important goal for individuals participating in cardiac rehabilitation (CR) programs. The purpose of this study was to assess the impact of comprehensive CR on QOL in patients with cardiovascular disease (CAD). METHODS: In this quasi-experimental before-after study, the files of 100 patients with CAD who were referred to rehabilitation department of Isfahan Cardiovascular Research Institute were studied using a consecutive sampling method. Data collection was performed from the patient's files including their demographics, ejection fraction, functional capacity, and resting heart rate. All patients participated in a comprehensive CR program and completed the validated questionnaire Short-Form 36 Health Status Survey (SF-36), before and after CR program. Data was analyzed based on sex and age groups (≥ 65 and < 65 years) using independent t-test and paired t-test (to compare variables between groups and before and after CR, respectively). RESULTS: After CR, scores of all physical domains of the SF-36 including physical function (PF), physical limitation (PL), body pain (BP) and vitality (V) in addition to general health (GH) were significantly improved in all patients (P < 0.05) compared to the baseline. Patients with age < 65 years had greater improvements in mental health (MH) and social function (SF) than patients with age ≥ 65 years (P < 0.05). Women had greater improvement in PF, V and MH compared to men (P < 0.05). CONCLUSION: These results indicated that CR can improve QOL in cardiac patients especially in women. Elderly patients get benefit the same as other patients in physical domains.