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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.

Objective: To assess the acute response of cardiac autonomic modulation (ACAM) during and after a session of virtual reality-based therapy (VRBT) compared to a session of conventional cardiovascular rehabilitation (CR) and to evaluate the effects of 12 weeks of training on this response., Methods: We assessed 28 volunteers (63.4 ± 12.5 years). The ACAM was judged by linear indexes of heart rate variability (HRV) in VRBT and CR sessions. Later, patients completed 12 weeks of VRBT+CR and the assessment was repeated at the 12 th week., Results: Throughout the 1 st VRBT session vagal withdrawal occurred (RMSSD/HFnu); sympathetic nervous system stimulation (LFnu) and progressive decrease of global HRV (SDNN). During the recovery, the SDNN, HFnu, and LFnu improved from the 5 th minute on both therapies. After 12 weeks, the LFnu, HFnu, and the LF/HF-ratio revealed no significant changes in Ex3-Ex4 equated to Rep during VRBT. In recovery, the HFnu and LFnu improved before the 5 th minute on both therapies., Conclusions: ACAM during and after the VRBT was comparable to CR, yet, the extents were greater in the VRBT. After 12 weeks of VRBT training, the subjects adapted to the exercises from the 15 th minute and exhibited faster recovery of HFnu and LFnu indexes compared to the 1 st week.

Background: Virtual reality-based therapy (VRBT) has been recently used in rehabilitation programs, as it can improve patient's adherence to treatment. However, patients' acceptance of VRBT has been scarcely investigated., Objective: To qualitatively analyze the perceptions and preferences of patients about the inclusion of VRBT to a conventional cardiovascular rehabilitation program (CRP)., Methods: Fifteen patients from a randomized clinical trial participated in focus groups for qualitative assessment., Results: Patients demonstrated good acceptance and satisfaction of VRBT. Physical and psychosocial benefits were highlighted, and patients reported the perception of higher exercise intensity in VRBT then when doing conventional training. In addition, the frequency of VRBT (once a week), associated with conventional treatment was reported as satisfactory. Cognitive aspects that influenced participation to the new approach were also raised by study participants., Conclusion: Patients with cardiac conditions demonstrated satisfaction with the inclusion of VRBT in a conventional CRP, demonstrating that VRBT has the potential to be a new approach for this patient population, allowing training diversification. Benefits perceived by patients include physical, mental, and social aspects., Trial Registered: NCT04336306 (https://clinicaltrials.gov/ct2/show/NCT04336306)., Competing Interests: Conflicts of interest There are no conflicts of interest., (Copyright © 2022 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier España, S.L.U. All rights reserved.)

Background: Cardiac rehabilitation (CR) barriers are well-understood in high-resource settings. However, they are under-studied in low-resource settings, where access is even poorer and the context is significantly different, including two-tiered healthcare systems and greater socioeconomic challenges., Objective: To investigate differences in characteristics of patients attending publicly versus privately funded CR and their barriers to adherence., Design and Setting: Observational, cross-sectional study in public and private CR programs offered in Brazil., Methods: Patients who had been attending CR for ≥ 3 months were recruited from one publicly and one privately funded CR program. They completed assessments regarding sociodemographic and clinical characteristics and the CR Barriers Scale., Results: From the public program, 74 patients were recruited, and from the private, 100. Participants in the public program had significantly lower educational attainment (P < 0.001) and lower socioeconomic status (P < 0.001). Participants in the private program had more cognitive impairment (P = 0.015), and in the public program more anxiety (P = 0.001) and depressive symptoms (P = 0.008) than their counterparts. Total barriers among public CR participants were significantly higher than those among private CR participants (1.34 ± 0.26 versus 1.23 ± 0.15/5]; P = 0.003), as were scores on 3 out of 5 subscales, namely: comorbidities/functional status (P = 0.027), perceived need (P < 0.001) and access (P = 0.012)., Conclusion: Publicly funded programs need to be tailored to meet their patients' requirements, through consideration of educational and psychosocial matters, and be amenable to mitigation of patient barriers relating to presence of comorbidities and poorer health status.

Abstract: Conrado de Freitas, M, Ricci-Vitor, AL, de Oliveira, JVNS, Quizzini, GH, Vanderlei, LCM, Silva, BSA, Zanchi, NE, Cholewa, JM, Lira, FS, and Rossi, FE. Appetite is suppressed after full-body resistance exercise compared with split-body resistance exercise: the potential influence of lactate and autonomic modulation. J Strength Cond Res 35(9): 2532-2540, 2021-The purposes of this study were to investigate the effects of full- vs. split-body resistance training on appetite and leptin response and to verify the potential involvement of lactate and autonomic modulation during this response in trained men. Twelve recreationally resistance-trained men (age = 26.1 ± 5.5 years) performed 3 randomized trials in 3 conditions: upper body (UB), lower body (LB), and full body (FB). The subjective rating of hunger was obtained through a visual analog scale. Leptin and lactate concentration were evaluated at rest, immediately after exercise, and during recovery. Heart rate variability in the time and frequency domains was recorded at baseline and during recovery (until 60 minutes after exercise) to assess autonomic modulation. The FB condition induced lower subjective hunger ratings than the UB at Post-1 hour (p < 0.05) and a significant difference in the area under the curve between conditions (p = 0.028) with lower hunger sensation for FB in relation to UB (p = 0.041). The FB presented greater lactate concentration and induced slower heart rate variability recovery in relation to UB and LB conditions (p < 0.05), and heart rate variability remained lower until 60 minutes after exercise compared with rest only in the FB condition. There was a significant negative correlation between subjective hunger ratings and lactate concentration only for the FB condition (r = -0.72, p = 0.028). Full-body resistance exercise induced lower subjective hunger ratings after exercise in relation to UB resistance exercise. The FB also induced higher lactate production and slower recovery of autonomic modulation compared with the UB and LB conditions. Future research is necessary to investigate a mechanistic relationship between lactate concentrations and hunger suppression after resistance exercise., (Copyright © 2019 National Strength and Conditioning Association.)

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., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Objective: The purpose of this study was to investigate the effects of adding virtual reality (VR) to maintenance cardiac rehabilitation (CR); it was hypothesized VR would increase adherence, motivation, and engagement., Methods: This study was a randomized, 1:1 concealed-allocation, single-blinded, 2 parallel-arm, crossover trial. Blinded assessments were undertaken at baseline (midprogram), 12 weeks, and 24 weeks after baseline. The setting was a single CR program of unlimited duration in Brazil. Participants were patients with cardiovascular diseases or risk factors who had been in the program for 3 months or longer. The CR program consisted of 3 supervised exercise sessions per week. In the VR arm, participants had 1 VR session of the 3 per week during the initial 12 weeks of the trial; this was withdrawn the subsequent 12 weeks. Measures were program adherence (% of 3 sessions/week over 12 weeks, ascertained in all participants), motivation (Behavioral Regulation in Exercise Questionnaire 3), and engagement (User Engagement Scale, adapted; vigor, dedication, and absorption subscales); all 3 were primary outcomes., Results: Sixty-one (83.6%) patients were randomly assigned (n = 30 to CR + VR); 54 (88.5%) were retained at 12 and 24 weeks. At baseline, participants had been in CR on average 7 years and had high engagement and motivation. CR + VR resulted in a significant increase in adherence at 12 weeks (baseline = 72.87%; 12 weeks = 82.80%), with significant reductions at 24 weeks when VR was withdrawn (65.48%); in the usual CR care arm, there were no changes over time. There was a significant effect for arm, with significantly higher adherence in the CR + VR arm than usual CR at 12 weeks (73.51%). Motivation decreased significantly from baseline to 12 weeks (4.32 [SD = 0.37] vs 4.02 [SD = 0.76]) and significantly increased from 12 to 24 weeks in the CR + VR arm (4.37 [SD = 0.36]). Absorption was significantly lower at 12 weeks in the CR + VR arm (6.79 [SD = 0.37] vs 6.20 [SD = 1.01])., Conclusion: Although VR increased program adherence, interspersing it with usual CR sessions actually decreased patient motivation and absorption., Impact: Supplementing a maintenance CR program with VR using "exergames" resulted in significantly greater adherence (8% increase or 3 of 36 sessions), and this was quite a robust effect given it was extinguished with the removal of VR. However, contrary to the hypotheses, offering 1 session of VR per week and 2 of usual CR exercise was related to lower motivation and absorption, which has implications for how clinicians design programs for this patient population., (© The Author(s) 2021. Published by Oxford University Press on behalf of the American Physical Therapy Association. All rights reserved. For permissions, please email: journals.permissions@oup.com.)

Objective: To analyze the interrater agreement among physiotherapists in using 7 risk stratification (RS) protocols to evaluate participants of cardiac rehabilitation (CR) and the main factors associated with disagreements that emerged during the RS process., Design: Cross-sectional observational study., Setting: Outpatient rehabilitation center., Participants: Patients (N=72) enrolled in CR with a diagnosis of cardiovascular disease or cardiovascular risk factors. Mean age was 65.62±12.14 y, and mean body mass index (calculated as weight in kilograms divided by height in meters squared) was 29.18±4.56., Interventions: Not applicable., Main Outcome Measures: The main outcome was to the agreement between 2 physiotherapists in the patients' RS process, using 7 protocols established in the literature for use in CR: American Association of Cardiovascular and Pulmonary Rehabilitation, American College of Sports Medicine, American Heart Association, Sociedade Brasileira de Cardiologia, Sociedad Española de Cardiología, and Société Française de Cardiologie. In addition, the main disagreement factors were assessed., Results: Interrater agreement was classified as moderate-to-good in the 7 included RS protocols (kappa index between 0.53-0.76). The most important aspects that led to disagreement between physiotherapists were reported in 5 categories. The protocol with the greater agreement index was the American College of Sports Medicine (93.10%; n=67), and the one with the greater disagreement was the American Association of Cardiovascular and Pulmonary Rehabilitation (27.80%; n=20)., Conclusions: Moderate-to-good interrater agreement among physiotherapists in using 7 RS protocols was observed. Major disagreements were the definition of abnormal hemodynamic responses, rhythm disorders, left ventricular dysfunction, and interpretation of the patient's clinical characteristics., (Copyright © 2020 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Background: Parkinson's disease (PD) produces autonomic changes, indicating lower parasympathetic modulation and global variability, but these changes need further studying regarding geometric methods., Objective: To investigate the autonomic modulation in individuals with PD using heart rate variability (HRV) indices obtained through geometric methods., Methods: This is a cross-sectional study that assessed 50 individuals, split into two groups: PD group (PDG; n=26; 75.36±5.21 years) and control group (CG; n=24; 75.36±5.21 years). We evaluated the autonomic modulation by measuring the heart rate beat-to-beat for 30 min with the individual in supine rest using a heart rate monitor and assessed geometric indices (RRtri, TINN, SD1, SD2, SD1/SD2 ratio, and qualitative analysis of the Poincaré plot)., Results: Significant reductions were found in RRtri, TINN, SD1, and SD2 indices among PDG compared to CG. Regarding the SD1/SD2 ratio, no significant changes were detected between the groups. The Poincaré plot demonstrated that individuals with PD had lower beat-to-beat dispersion in RR intervals, in addition to greater long-term dispersion of RR intervals compared to CG., Conclusions: The results suggest a reduction in the parasympathetic autonomic modulation and global variability in individuals with PD compared to controls, regardless of sex, age, and body mass index.

Aim: To analyze the correlation between the appearance of signs/symptoms during a cardiovascular rehabilitation program and linear indexes of the heart rate variability (HRV) at rest., Methods: To carry out the present observational longitudinal study, 48 patients were analyzed. The protocol was divided into two stages. First, the patients had their personal details collected, and the autonomic modulation at rest was evaluated by HRV. Second, they underwent 36 sessions of the cardiovascular rehabilitation program to evaluate signs/symptoms. Then, just for analysis of the data, they were divided into two groups: the group without signs/symptoms (n = 26; 65.15 ± 9.7 years); and the group with signs/symptoms (n = 22; 66.77 ± 14.4 years). The HRV indexes were compared by ancova. The effect size was measured through the partial eta-squared. Pearson's and Spearman's correlations (P < 0.05) were used to analyze the data, and linear regression was applied., Results: A total of 103 signs/symptoms occurred. The group with signs/symptoms presented lower values of HRV indexes when compared with the group without signs/symptoms, especially for the parasympathetic indexes with a large effect size. The root mean square of successive differences (rMSSD), percentage of adjacent RR intervals with a difference of duration >50 ms (pNN50), high-frequency spectral component (HF) varying from 0.15 to 0.4 Hz (expressed as ms 2 ), dispersion of the points perpendicular to the line of identity and represents the instantaneous record of the beat-to-beat variability (SD1) and SD1/scatter of points along the identity line and represents the HRV in long-term records (SD2) index presented a negative correlation with the appearance of signs/symptoms. When the linear regression was applied, the rMSSD, SD1 and SD1/SD2 showed negative values of β (P < 0.05)., Conclusions: Patients with lower HRV are more likely to have signs/symptoms. The rMSSD, pNN50, HF (expressed as ms 2 ), SD1 and SD1/SD2 index presented a negative correlation with the appearance of signs/symptoms. For rMSSD, SD1 and SD1/SD2, the lower the values of these HRV indexes, the greater the risk of appearance of signs/symptoms. Geriatr Gerontol Int 2020; 20: 853-859., (© 2020 Japan Geriatrics Society.)

Metabolic syndrome (MetS) is a growing epidemic related with higher values of blood pressure (BP) and autonomic dysfunction. Scientific evidence has been indicating that functional resistance training (FRT) is superior over conventional (CRT) for muscle fatigue and pain, yet its effects on autonomic modulation (AM), BP and heart rate in MetS are unclear. We theorized that FRT can be superior to CRT in MetS patients because of larger muscle activation. This study compares FRT and CRT on AM, blood pressure, heart rate and muscle strength. Thirty-eight sex and age matched individuals (40 to 60 years) were randomized for FRT or CRT, with training intensity varying gradually from 30%-100% of one maximal repetition test (1MR), 3 times/week for 30 sessions. All outcomes were evaluated at baseline and post training. AM was assessed by heart rate variability (mean RR, RMSSD, SDNN, LF, HF, TINN, RRtri, SD1 and SD2). BP (mmHg) was obtained by cuff measures. Muscle strength was assessed by 1MR. An increase in cardiac parasympathetic activity was observed in individuals allocated to FRT in comparison to CRT group (RMSSD ∆40%; SD1 ∆39%; and HF ms 2 ∆80%). Moreover, just FRT was capable of reducing BP post intervention (SBP from 129.21 ± 19.02 to 118.94 ± 14.14 mmHg, p < .009,/d/ = 0.49; DBP from 85.26 ± 11.48 to 77.76 ± 8.93 mmHg, p < .01,/d/ = 0.51). Both groups had a similar increase in muscle strength and no changes between HR. Progressive FRT was more beneficial to CRT regarding AM, increasing vagal activity, and reducing blood pressure in MetS individuals.

Objective: To analyze the acute hemodynamic effects of adding virtual reality-based therapy (VRBT) using exergames for patients undergoing cardiac rehabilitation (CR)., Design: Crossover trial., Setting: Outpatient rehabilitation center., Participants: Patients (N=27) with a diagnosis of cardiovascular disease or cardiovascular risk factors. Mean age (years) ± SD was 63.4±12.7 and mean body mass index (kg/m2) ± SD was 29.0±4.0., Interventions: Patients performed 1 VRBT session and 1 CR session on 2 nonconsecutive days. Each session comprised an initial rest, warm-up, conditioning, and recovery. During warm-up, in the VRBT session, games were performed with sensors to reproduce the movements of avatars and, in the CR session, patients were required to reproduce the movements of the physiotherapists. In the conditioning phase for VRBT, games were also played with motion sensors, dumbbells, and shin guards. The CR session consisted of exercises performed on a treadmill. The intensity of training was prescribed by heart rate reserve (HRR; 40%-70%)., Main Outcome Measures: The primary outcomes were heart rate, blood pressure, respiratory rate (RR), rating of perceived exertion (RPE), and peripheral oxygen saturation, evaluated before, during, and after the VRBT or CR session on 2 nonconsecutive days. The secondary outcome was to evaluate whether the patients achieved the prescribed HRR and the percentage of time they maintained this level during the VRBT session., Results: VRBT produces a physiological similar pattern of acute hemodynamic effects in CR. However, there was greater magnitude of heart rate, RR, and RPE (P<.01) during the execution of VRBT and until 5 minutes of recovery, observed at the moments of rest, and 1, 3, and 5 minutes of recovery., Conclusions: Although the VRBT session produces similar physiological acute hemodynamic effects in CR, greater magnitudes of heart rate, RR, and RPE were observed during its execution and up to 5 minutes after the session., (Copyright © 2020 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.)

Background: Ethanol vehicles release exhaust gases that contribute to the formation of secondary organic aerosols (SOA)., Objective: To determine in vivo toxicity resulting from exposure to SOA derived from vehicles using different ethanol-gasoline blends (E0, E10, E22, E85W, E85S, E100)., Methods: Exhaust emissions from vehicles using ethanol blends were delivered to a photochemical chamber and reacted to produce SOA. The aerosol samples were collected on filters, extracted, and dispersed in an aqueous solutions and intratracheally instilled into Sprague Dawley rats in doses of 700 μg/0.2 ml. After 45 min and 4 h pulmonary and cardiac chemiluminescence (CL) was measured to estimate the amount of reactive oxygen species (ROS) produced in the lungs and heart. Inflammation was measured by differential cell count in bronchoalveolar lavages (BAL)., Results: Statistically and biologically significant differences in response to secondary particles from the different fuel formulations were detected. Compared to the control group, animals exposed to SOA from gasoline (E0) showed a significantly higher average CL in the lungs at 45 min. The highest CL averages in the heart were observed in the groups exposed to SOA from E10 and pure ethanol (E100) at 45 min. BAL of animals exposed to SOA from E0 and E85S had a significant increased number of macrophages at 45 min. BAL neutrophil count was increased in the groups exposed to E85S (45 min) and E0 (4 h). Animals exposed to E0 and E85W had increased BAL lymphocyte count compared to the control and the other exposed groups., Discussion: Our results suggest that SOA generated by gasoline (E0), followed by ethanol blends E85S and E85W, substantially induce oxidative stress measured by ROS generation and pulmonary inflammation measured by the recruitment of white blood cells in BAL., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The aim of this study was to verify the autonomic modulation and blood pressure after adenosine-5'-triphosphate (ATP) supplementation associated to acute aerobic exercise in hypertensive women. Eleven hypertensive women (age, 61.8±5.0 years) completed a randomized, double blind trial: ATP supplement condition (ATP=400 mg) or placebo. After 30 min of supplementation or placebo intake, the subjects performed 30 min of aerobic exercise (70%-75% of maximum heart rate). The autonomic modulation was assessed by heart rate variability during rest and recovery (postexercise until 30 min of recovery), the square root of the mean squared difference between adjacent RR intervals (RMSSD), standard deviation of successive values (SDNN), low frequency (LF) and high frequency (HF) were measured. The blood pressure (systolic blood pressure [SBP] and diastolic blood pressure, mmHg) were recorded at rest, immediately postexercise, post-10, post-20, and post-30 min after exercise. For RMSSD, there was statistically significant difference during recovery, with higher RMSSD for ATP compared to placebo (rest=16.4±8.5 vs. placebo=11.6±4.0; ATP=18.5±9.7 msec; P =0.020). When analyzing the delta (recovery minus rest), the RMSSD (ATP=2.1± 7.2 msec vs. placebo=-4.7±7.5 msec; P =0.009), LF (ATP=-19.8±122.7 vs. placebo=-94.1±200.2 msec2; P =0.02), and SDNN (ATP=-2.8±12.2 msec vs. placebo=-10.6±10.5 msec; P =0.010) were higher for ATP than placebo. Furthermore, there was a greater postexercise hypotension at 20 min for ATP (SBP: ATP=-13.2±8.4 mmHg vs. placebo=-6.1±9.9 mmHg; P =0.006). Acute ATP supplementation promoted greater postexercise hypotension for systolic blood pressure and induced faster recovery of heart rate variability in hypertensive women., Competing Interests: CONFLICT OF INTEREST No potential conflict of interest relevant to this article was reported.

To investigate the effects of full versus split body resistance exercise on postexercise hypotension and autonomic modulation in trained men. Sixteen resistance recreationally trained males (age, 24.9±5.3 years) performed three randomized trials: upper body (UB), lower body (LB), and full body (FB) conditions. Blood pressure and heart rate variability were collected at rest, immediately postexercise, post-10, and post-30 min during recovery. For systolic blood pressure, delta (30 min minus rest) was lower for the FB condition compared to the UB (-10.1±7.4 mmHg [FB] vs. -3.3±12.6 mmHg [LB] vs. -1.9±8.1 mmHg [UB], P =0.004). For diastolic blood pressure (-8.2±10.9 mmHg [FB] vs. -1.5±9.8 mmHg [LB] vs. -8.7±11.4 mmHg [UB], P =0.038) and mean blood pressure delta during recovery (-11.7±14 mmHg [FB] vs. -2.2±10.6 mmHg [LB] vs. -5.2±6.8 mmHg [UB], P =0.045), there were statistically significant lower values in the FB condition in relation to the LB condition. Regarding heart rate variability, there were no significant differences between conditions, however, the square root of the mean squared difference between adjacent RR intervals presented an increase until post-30 during recovery ( P <0.001), and there was a higher values of low frequency and lower values of high frequency across time ( P <0.001). Postexercise hypotension was influenced by the amount of muscle mass involved in a bout of resistance exercise, with the FB condition inducing lower systolic blood pressure in relation to the UB after exercise, as well as a great decrease in postexercise diastolic and mean blood pressure compared with the LB. The autonomic modulation response was similar between conditions during recovery., Competing Interests: CONFLICT OF INTEREST No potential conflict of interest relevant to this article was reported.

Despite the various standard non-linear measurements used in autonomic modulation (AM) assessments usually being applied to long time-series, such analyses can sometimes be applied to shorter term series. To overcome this disadvantage, chaotic global methods were formulated by putting together heart rate variability (HRV) linear methods. Chaos provides information about vegetative function control related to cardiovascular risks. Applying this method can be useful to investigate the complexity of the health condition after resistance training protocols, as a therapeutic intervention in AM in metabolic syndrome individuals (MetS). This study aimed to compare the effects of two resistance training programs (conventional vs functional) in MetS using nonlinear analysis of AM. MetS subjects (n=50) of both sexes aged 40 to 60 years were randomly divided into two programs; a group of 12 people served as a control group. Both groups performed 30 sessions of training. AM was assessed in the chaos domain by chaotic global techniques. The main results showed that both resistance training, functional and conventional, increased chaos when compared to the control group, respectively, observed by chaotic forward parameter (CFP)1 (13.9±17.9 vs 12.8±14.4 vs -2.23±7.96; P≤0.05) and CFP3 (15.4±19.8 vs 21.9±13.2 vs -4.82±11.4; P≤0.05). In addition, 30 sessions of both resistance programs increased chaos, and non-linear analysis enabled discrimination of AM after interventions when compared to the control group.

This study addresses evidence concerning elastic tubing resistance training (ET) on autonomic modulation in patients with chronic obstructive pulmonary disease (COPD). Autonomic dysfunction is common in COPD and contributes to the development of arrhythmias and sudden death. Along with autonomic dysfunction, muscle dysfunction is related to functional limitations and prognosis of the disease. This study investigated the effects of ET on autonomic modulation, muscle strength, and walking distance in COPD. Subjects were divided into two groups, ET ( n = 20; 66,5 ± 8,9 y; 25,5 ± 3,5 kg/m 2 ; FEV 1 /FVC: 50,3 ± 11,0) and conventional training ( n = 19; 66,0 ± 6,9; 27,1 ± 4,3; FEV 1 /FVC: 55,05 ± 9,56). Both groups undertook 24 sessions for 60 minutes, 3 times in a week. The significance level was p ≤ 0,05. Autonomic modulation was evaluated using heart rate variability in the time (rMSSD, ms) and frequency domain (HF, ms). Strength for upper and lower limbs was measured using dynamometry and walking distance was measured using a 6-minute walking test. There were no significant differences in the outcomes between groups. There was an increment to rMSSD [(16,7 ± 11,0 versus 20,8 ± 14,9) versus (14,2 ± 10,0 versus 17,4 ± 12,1)], HF [(141,9 ± 191,3 versus 234,9 ± 335,7) versus (94,1 ± 123,5 versus 177,6 ± 275,5)], shoulder abduction [(50,1 ± 19,6 versus 56,9 ± 20,4) versus (50,5 ± 19,0 versus 56,9 ± 19,3)], knee flexion [(101,9 ± 34,0 versus 116,8 ± 43,3) versus (98,6 ± 21,5 versus 115,1 ± 30,8)], and walking test [(433,0 ± 84,8 versus 468,9 ± 90,8) versus (397,4 ± 99,8 versus 426,3 ± 101,6)] after training for ET and conventional training, respectively. In conclusion, ET improves autonomic modulation in COPD with additional benefits for strength and cardiorespiratory capacity similar to conventional training.

Background: Epidemiological studies have linked exposures to ambient fine particulate matter (PM 2.5 ) and traffic with autonomic nervous system imbalance (ANS) and cardiac pathophysiology, especially in individuals with preexisting disease. It is unclear whether metabolic syndrome (MetS) increases susceptibility to the effects of PM 2.5 . We hypothesized that exposure to traffic-derived primary and secondary organic aerosols (P + SOA) at ambient levels would cause autonomic and cardiovascular dysfunction in rats exhibiting features of MetS. Male Sprague Dawley (SD) rats were fed a high-fructose diet (HFrD) to induce MetS, and exposed to P + SOA (20.4 ± 0.9 μg/m 3 ) for 12 days with time-matched comparison to filtered-air (FA) exposed MetS rats; normal diet (ND) SD rats were separately exposed to FA or P + SOA (56.3 ± 1.2 μg/m 3 )., Results: In MetS rats, P + SOA exposure decreased HRV, QTc, PR, and expiratory time overall (mean effect across the entirety of exposure), increased breathing rate overall, decreased baroreflex sensitivity (BRS) on three exposure days, and increased spontaneous atrioventricular (AV) block Mobitz Type II arrhythmia on exposure day 4 relative to FA-exposed animals receiving the same diet. Among ND rats, P + SOA decreased HRV only on day 1 and did not significantly alter BRS despite overall hypertensive responses relative to FA. Correlations between HRV, ECG, BRS, and breathing parameters suggested a role for autonomic imbalance in the pathophysiologic effects of P + SOA among MetS rats. Autonomic cardiovascular responses to P + SOA at ambient PM 2.5 levels were pronounced among MetS rats and indicated blunted vagal influence over cardiovascular physiology., Conclusions: Results support epidemiologic findings that MetS increases susceptibility to the adverse cardiac effects of ambient-level PM 2.5 , potentially through ANS imbalance.

Chronic obstructive pulmonary disease (COPD) is associated with autonomic dysfunctions that can be evaluated through heart rate variability (HRV). Resistance training promotes improvement in autonomic modulation; however, studies that evaluate this scenario using geometric indices, which include nonlinear evaluation, thus providing more accurate information for physiological interpretation of HRV, are unknown. This study aimed to investigate the influence of resistance training on autonomic modulation, using geometric indices of HRV, and peripheral muscle strength in individuals with COPD. Fourteen volunteers with COPD were submitted to resistance training consisting of 24 sessions lasting 60 min each, with a frequency of three times a week. The intensity was determined as 60% of one maximum repetition and was progressively increased until 80% for the upper and lower limbs. The HRV and dynamometry were performed at two moments, the beginning and the end of the experimental protocol. Significant increases were observed in the RRtri (4·81 ± 1·60 versus 6·55 ± 2·69, P = 0·033), TINN (65·36 ± 35·49 versus 101·07 ± 63·34, P = 0·028), SD1 (7·48 ± 3·17 versus 11·04 ± 6·45, P = 0·038) and SD2 (22·30 ± 8·56 versus 32·92 ± 18·78, P = 0·022) indices after the resistance training. Visual analysis of the Poincare plot demonstrated greater dispersion beat-to-beat and in the long-term interval between consecutive heart beats. Regarding muscle strength, there was a significant increase in the shoulder abduction and knee flexion. In conclusion, geometric indices of HRV can predict improvement in autonomic modulation after resistance training in individuals with COPD; improvement in peripheral muscle strength in patients with COPD was also observed., (© 2015 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.)

This study compared autonomic modulation in swimmers and non-athletes in relation to body composition. A total of 28 athletes with a mean age of 19.7 ± 2.9 years were evaluated who had at least 2 years of swimming training, trained approximately 7,000 m per day, with a frequency of 5 days per week, and who competed at national level. The control group was made up of 21 volunteers (23.0 ± 2.5 years), who did not practice regular physical activity (<2 hours per week). Body composition was estimated using dual-energy x-ray absorptiometry, and autonomic modulation was assessed by heart rate variability (HRV). The results show that there were significant differences in autonomic modulation and body composition between the groups, and that the athletes had a higher overall variability (standard deviation of all normal intervals between consecutive heart beats [SDNN]: 78.1 [72.5-93.5] × 61.1 [56.4-75.7], p = 0.022) and greater autonomic balance (LF/HF: 0.96 [0.88-1.35] × 0.71 [0.56-0.93], p = 0.023), compared with the non-athletes, respectively. In addition, a moderate and positive relation was obtained between fat-free mass and the square root of the squared differences between consecutive heartbeat intervals (RMSSD: r = 0.526, p = 0.004 × r = 0.456, p = 0.038), (SDNN: r = 0.617, p = 0.001 × r = 0.571, p = 0.007) and low frequency (LFms: r = 0.517, p = 0.005 × r = 0.600, p = 0.004) in the athletes and non-athletes, respectively, without a correlation between fat mass (FM). The conclusion is that young highly trained swimmers had lower FM, increased fat-free mass, and better HRV than young adult non-athletes and suggests that a lower quantity of FM and, especially, a greater fat-free mass (FFM) are linked to better autonomic modulation. Thus, this study could contribute to coaches and trainers establishing greater performance by better autonomic modulation and greater quantity of FFM.

Background: The chronic obstructive pulmonary disease (COPD) is associated with the strength and resistance decreasing in addition to the dysfunction on autonomic nervous system (ANS). The aerobic training isolated or in association with the resistance training showed evidence of beneficial effects on an autonomic modulation of COPD; however, there are no studies addressing the effect of isolated resistance training., Aims: This study aims at investigating the influence of resistance training on an autonomic modulation through heart rate variability (HRV), functional capacity and muscle strength in individuals with COPD., Design: Clinical series study., Setting: Outpatients., Population: The study involved 13 individuals with COPD., Methods: The experimental protocol was composed by an initial and final evaluation that consisted in autonomic evaluations (HRV), cardiopulmonary functional capacity evaluation (6-minute walk test) and strength evaluation (dynamometry) in addition by the resistance training performed by 24 sessions lasted 60 minutes each one and on a frequency of three times a week. The intensity was determined initially with 60% of one maximum repetition and was progressively increased in each five sessions until 80%., Results: The HRV temporal and spectral indexes analysis demonstrates improvement of autonomic modulation, with significant statistical increases to sympathetic and parasympathetic components of ANS representing by SDNN, LF and HF. In addition, it was observed significant statistical increases to shoulder abduction and knee flexion strength and functional capacity., Conclusion: The exclusive resistance training performed was able to positively influence the autonomic modulation; in addition it promoted benefits on cardiorespiratory functional capacity and strength benefits in individuals with COPD., Clinical Rehabilitation Impact: This study could contribute to clinical and professionals researchers that act with COPD, even though the resistance component of pulmonary rehabilitation presents consensual benefits on several healthy indicators parameters. There is no evidence about the effects on HRV before. Moreover, this study showed, on clinical practice, the HRV uses as an ANS activity on sinus node evaluation and highlights further importance on scientific context.