Effect of an exercise-based cardiac rehabilitation program on quality of life of patients with chronic Chagas cardiomyopathy: results from the PEACH randomized clinical trial.

To investigate the effect of an exercise-based cardiac rehabilitation program on the quality of life (QoL) of patients with chronic Chagas cardiomyopathy (CCC). PEACH study was a single-center, superiority randomized clinical trial of exercise training versus no exercise (control). The sample comprised Chagas disease patients with CCC, left ventricular ejection fraction < 45%, without or with HF symptoms (CCC stages B2 or C, respectively). QoL was assessed at baseline, after three months, and at the end of six months of follow-up using the SF-36 questionnaire. Patients randomized for the exercise group (n = 15) performed exercise training (aerobic, strength and stretching exercises) for 60 min, three times a week, during six months. Patients in the control group (n = 15) were not provided with a formal exercise prescription. Both groups received identical nutritional and pharmaceutical counseling during the study. Longitudinal analysis of the effects of exercise training on QoL, considering the interaction term (group × time) to estimate the rate of changes between groups in the outcomes (represented as beta coefficient), was performed using linear mixed models. Models were fitted adjusting for each respective baseline QoL value. There were significant improvements in physical functioning (ß = + 10.7; p = 0.02), role limitations due to physical problems (ß = + 25.0; p = 0.01), and social functioning (ß = + 19.2; p < 0.01) scales during the first three months in the exercise compared to the control group. No significant differences were observed between groups after six months. Exercise-based cardiac rehabilitation provided short-term improvements in the physical and mental aspects of QoL of patients with CCC.Trial registration: ClinicalTrials.gov Identifier: NCT02517632; August 7, 2015.

Neuro-Cardiovascular Responses to Sympathetic Stimulation in Fighter Pilots.

INTRODUCTION: The chronic effects of regular exposure to high acceleration levels (G-force) on the neuro-cardiovascular system are unclear. We compared the mean arterial pressure (MAP) and cardiac autonomic modulation between nonpilots (NP) vs. military fighter (FP) and transport (TP) pilots. Additionally, we correlated the cardiac autonomic indices with the cardiorespiratory fitness and flight experience of FP.METHODS: A total of 21 FP, 8 TP, and 20 NP performed a tilt test (TT), during which beat-to-beat blood pressure and heart rate were recorded.RESULTS: No difference was detected between groups for changes in MAP and heart rate variability indices during the TT. However, the analysis of areas under the curves showed a greater increase in MAP in FP vs. TP and NP. Conversely, there was a greater decrease in indices reflecting vagal modulation in TP vs. FP and NP (rMSSD, pNN50, and SDNN), and a greater increase in heart rate and sympathovagal balance in TP vs. other groups (LF/HF). The maximal oxygen uptake was strongly correlated with the vagal reserve in FP (r = -0.74). Moreover, the total flying hours of FP were positively correlated with resting HFnu (r = 0.47) and inversely correlated with resting LFnu (r = -0.55) and LF/HF (r = -0.46).CONCLUSION: FP had a higher pressor response to TT than TP and NP. Vagal withdrawal and sympathovagal increase induced by TT in FP were similar vs. NP and attenuated vs. TP. Greater cardiorespiratory fitness and accumulated flying hours in FP seemed to favor lower sympathetic and greater vagal modulation at rest.dos Santos Rangel MV, de Sá GB, Farinatti P, Borges JP. Neuro-cardiovascular responses to sympathetic stimulation in fighter pilots. Aerosp Med Hum Perform. 2023; 94(10):761-769.

Body Mass Index but not Physical Activity Level Moderates Lowered Cardiac Baroreflex Sensitivity in People Living with HIV.

Reduced cardiac baroreflex sensitivity (cBRS) is an autonomic marker associated with a worse cardiovascular prognosis. Whether cBRS is lowered in people living with HIV (PLHIV) is yet unclear, as well as potential moderator effects of body mass index (BMI) or physical activity (PA) level. The present study aims to compare the spontaneous cBRS in PLHIV vs. HIV-uninfected controls, and to determine among PLHIV the relationship between cBRS vs. body mass index (BMI) and PA level. Total, upward (cBRS+), and downward (cBRS-) cBRS gains were assessed using the sequential method from beat-to-beat blood pressure at rest in 16 PLHIV (46.5±8.4 years) under antiretroviral therapy for at least 6 months, and 16 HIV-uninfected controls (CTL; 42.1±8.0 years). PA level was assessed by the Physical Activity Questionnaire (IPAQ short version) overall score. PLHIV showed lower total cBRS (8.7±3.1 vs. 15.3±7.7 ms.mmHg-1; p < 0.01), cBRS+ (9.2±4.9 vs. 16.0±6.8 ms.mmHg-1; p < 0.01) and cBRS- (9.5±4.9 vs. 15.3±9.3 ms.mmHg-1; p < 0.01) vs. CTL. No between-group difference was found for BMI (PLHIV: 25.2±2.6 vs. CTL: 26.8±3.2 kg.m-2; p > 0.05) or IPAQ score (PLHIV: 2.4±1.0 vs. CTL: 2.0±1.4; p > 0.05). In PLHIV, total cBRS was inversely correlated vs. BMI (r = -0.44; p = 0.04), but not vs. IPAQ score (r = 0.17; p = 0.26). HIV infection may reduce spontaneous cBRS, which seemed to be moderated by higher BMI, but not PA level of PLHIV.

Comparative effects of a cardiovascular rehabilitation program on functional capacity in patients with chronic chagasic cardiomyopathy with or without heart failure.

PURPOSE: The aim of the present study was to evaluate the effects of cardiovascular rehabilitation (CR) on functional capacity of patients with chronic chagasic cardiomyopathy (CCC) and to compare the responses between CCC patients without and with heart failure (HF). MATERIALS AND METHODS: A longitudinal observational retrospective study was carried out including 36 patients with CCC without HF (stage B2 [n = 7]) and with HF (stage C [n = 29]), who participated in a CR program. Functional capacity was assessed by a maximal progressive cardiopulmonary exercise test performed on a treadmill. The longitudinal effects of the CR on functional capacity were determined by linear mixed models that included an interaction term to evaluate the differential responses between patients without and with HF. RESULTS: Significant improvements in peak oxygen consumption, resting heart rate and blood pressure, and maximum pulmonary ventilation were observed for the overall study sample, with no apparent differential effects according to the presence of HF. CONCLUSIONS: CR significantly improved functional capacity of patients with CCC. The responses to CR appear to be similar among patients without and with HF, reinforcing the need for its inclusion as a standard treatment strategy of CCC.Implications for rehabilitationExercise-based cardiovascular rehabilitation (CR) is a safe strategy that improves functional capacity, cardiac function, and quality of life in patients with several cardiovascular diseases, and recent studies also suggested a potential beneficial effect of CR in chronic chagasic cardiomyopathy (CCC).In this observational study, CR seems to equally improve exercise capacity, resting heart rate, resting blood pressure, and maximum pulmonary ventilation in patients with CCC without (stage B2) and with heart failure (stage C).Cardiovascular rehabilitation should be included as a standard treatment strategy for patients with CCC, regardless the severity of cardiomyopathy.

The effects of exercise training on autonomic and hemodynamic responses to muscle metaboreflex in people living with HIV/AIDS: A randomized clinical trial protocol.

BACKGROUND: People living with HIV (PLHIV) present impaired muscle metaboreflex, which may lead to exercise intolerance and increased cardiovascular risk. The muscle metaboreflex adaptations to exercise training in these patients are unknown. The present study aims to investigate the effects of a supervised multimodal exercise training on hemodynamic and autonomic responses to muscle metaboreflex activation in PLHIV. METHODS AND DESIGN: In this randomized clinical trial protocol, 42 PLHIV aged 30-50 years will be randomly assigned at a ratio of 1:1 into an intervention or a control group. The intervention group will perform exercise training (3x/week during 12 weeks) and the control group will remain physically inactive. A reference group composed of 21 HIV-uninfected individuals will be included. Primary outcomes will be blood pressure and heart rate variability indices assessed during resting, mental stress, and activation of muscle metaboreflex by a digital sphygmomanometer and a heart rate monitor; respectively. Mental stress will be induced by the Stroop Color-Word test and muscle metaboreflex will be activated through a post-exercise circulatory arrest (PECA) protocol, being the latter performed without and with the application of a capsaicin-based analgesic balm in the exercised limb. Secondary outcomes will be heart rate, peripheral vascular resistance, stroke volume, cardiac output, blood lactate, anthropometric markers and handgrip maximal voluntary contraction. The intervention and control groups of PLHIV will be evaluated at baseline and after the intervention, while the HIV-uninfected reference group only at baseline. DISCUSSION: The findings of the present study may help to elucidate the muscle metaboreflex adaptations to exercise training in PLHIV. TRIAL REGISTRATION: This study will be performed at University of Rio de Janeiro State following registration at ClinicalTrials.gov as NCT04512456 on August 13, 2020.

Muscle mass, strength, bone mineral density and vascular function in middle-aged people living with HIV vs. age-matched and older controls.

INTRODUCTION: Combination antiretroviral therapy (cART) substantially extended the life of people living with HIV (PLHIV). However, prolonged HIV infection and cART increase the risk of comorbidities accelerating age-related muscle, bone, and vascular disorders. This cross-sectional study compared muscle mass and strength, bone mineral density (BMD), and vascular function in middle-aged PLHIV treated with cART vs. non-infected age-matched and older controls. METHODS: After careful screening for secondary diseases and medications, body composition, muscular and vascular function were assessed in 12 PLHIV (43.9±8.7 yrs old; HIV-infection for 16.2±8.6 yrs; on cART for 11.6±9.2 yrs), 12 age-matched (CONT, 43.2±8.5 yrs old), and 12 older (OLDER, 74.4±8.3 yrs old) controls through dual x-ray absorptiometry, isokinetic dynamometry, and venous occlusion plethysmography, respectively. RESULTS: PLHIV and CONT showed similar relative muscle mass (65.3±8.0 vs. 66.9±7.3%, respectively; P= 0.88) and strength (160.7±53.9 vs. 152.0±52.9 N.m-1, respectively; P= 0.90), which were greater than OLDER (80.6±18.8 N.m-1; P= 0.001). Total BMD was similar in PLHIV (1.04±0.13 g.cm-2) and OLDER (1.00±0.15 g.cm-2, P= 0.86), and both groups presented lower values than CONT (1.20±0.13 g.cm-2, P< 0.01). No significant difference across groups was detected for macrovascular reactivity (P= 0.32). CONCLUSION: Age-related osteopenia might be accelerated in middle-aged PLHIV on prolonged cART, as their BMD approached values found in older adults. On the other hand, muscle mass, isokinetic strength, and vasodilation capacity were similar in PLHIV and age-matched uninfected controls.

Effects of exercise training on bone mineral density in adults living with HIV: a retrospective study.

Background: Evidence on the effects of exercise training on the bone health of men and women living with HIV (MLHIV and WLHIV) is limited.Objective: To investigate the effects of a long-term multimodal exercise program on the bone mineral density (BMD) of MLHIV and WLHIV.Methods: A retrospective cohort of 39 patients (13 women; 48.4 ± 7.6 y; HIV-infection for 15.5 ± 6.5 y; combined antiretroviral therapy for 12.2 ± 7.0 y) performed a multimodal exercise program (60-min sessions of aerobic, resistance, and flexibility exercises performed 3 times/week for 9-106 months). MLHIV and WLHIV were allocated into groups showing either advanced osteopenia/osteoporosis or normal BMD (+ or -).Results: MLHIV+ increased BMD at the femoral neck, total femur, and lumbar spine (∼3-4%) compared to MLHIV- (p ≤ 0.03). Changes in whole-body BMD were similar between MLHIV groups (p = 0.55). WLHIV+ exhibited higher loss of BMD at the femoral neck (∼6%) than WLHIV- (p = 0.04), whereas reductions in the whole-body, total femur, and lumbar spine (∼3-5%) were similar between groups (p ≥ 0.25). Among men, changes in femoral neck BMD were inversely correlated to femoral neck T-score (r = -0.62; p < 0.001), but not to the time of follow-up, appendicular skeletal muscle mass (ASM) index, or age (p ≥ 0.08). In women, these changes were inversely correlated with time of follow-up (r = -0.58) and age (r = -0.70) and positively correlated with femoral neck T-score (r = 0.46) and ASM index (r = 0.47) (p < 0.01).Conclusion: Multimodal exercise training may improve the BMD in people living with HIV, especially men with advanced osteopenia/osteoporosis. Adjuvant therapies to exercise should be considered to counteract losses in WLHIV.

The Effects of Acute Aerobic Exercise on Blood Pressure, Arterial Function, and Heart Rate Variability in Men Living With HIV.

PURPOSE: This study aims to investigate the effects of acute cycling on blood pressure (BP), arterial function, and heart rate variability (HRV) in men living with HIV (MLHIV) using combined antiretroviral therapy (cART). METHODS: Twelve MLHIV (48.7 ± 9.2 years; 25.2 ± 2.8 kg m-2) and 13 healthy controls (41.2 ± 9.9 years; 26.3 ± 2.9 kg m-2) performed a cycling bout (ES) (intensity: 50% oxygen uptake reserve; duration: time to achieve 150 kcal-MLHIV: 24.1 ± 5.5 vs. controls: 23.1 ± 3.0 min; p = 0.45), and a 20-min non-exercise session (NES). RESULTS: At rest (p < 0.05), MLHIV presented higher brachial systolic/diastolic BP (SBP/DBP: 123.2 ± 14.2/76.8 ± 6.3 vs. 114.3 ± 5.1/71.6 ± 2.6 mmHg) and central BP (cSBP/cDBP: 108.3 ± 9.3/76.5 ± 6.5 vs. 101.6 ± 4.9/71.3 ± 4.4 mmHg) vs. controls but lower absolute maximal oxygen uptake (2.1 ± 0.5 vs. 2.5 ± 0.3 L min-1) and HRV indices reflecting overall/vagal modulation (SDNN: 24.8 ± 7.1 vs. 42.9 ± 21.3 ms; rMSSD: 20.5 ± 8.5 vs. 38.1 ± 22.8 ms; pNN50: 3.6 ± 4.2 vs. 13.6 ± 11.3%). DBP postexercise lowered in controls vs. MLHIV (∼4 mmHg, p < 0.001; ES: 0.6). Moreover, controls vs. MLHIV had greater reductions (p < 0.05) in augmentation index (-13.6 ± 13.7 vs. -3.1 ± 7.2% min-1; ES: 2.4), and HRV indices up to 5 min (rMSSD: -111.8 ± 32.1 vs. -75.9 ± 22.2 ms min-1; ES: 3.8; pNN50: -76.3 ± 28.3 vs. -19.0 ± 13.7% min-1; ES: 4.4). Within-group (ES vs. NES; p < 0.05) reductions occurred in controls for SBP (∼10 mmHg, 2 h), DBP (∼6 mmHg, 20, 30, and 70 min), cSBP (∼9 mmHg, 30 min), cDBP (∼7 mmHg, 30 and 70 min), augmentation index (∼10%, 30 min), and pNN50 (∼20%; up to 2 h), while in MLHIV only cSBP (∼6 mmHg, 70 min) and cDBP (∼4 mmHg, 30 min) decreased. Similar increases (up to 5 min) in heart rate (∼22 bpm) and decreases in SDNN (∼18 ms) and rMSSD (∼20 ms) occurred in both groups. CONCLUSION: MLHIV under cART exhibited attenuated postexercise hypotension vs. healthy controls, which seemed to relate with impairments in vascular function.

Muscle metaboreflex adaptations to exercise training in health and disease.

Abnormalities in the muscle metaboreflex concur to exercise intolerance and greater cardiovascular risk. Exercise training benefits neurocardiovascular function at rest and during exercise, but its role in favoring muscle metaboreflex in health and disease remains controversial. While some authors demonstrated that exercise training enhanced the sensitization of muscle metabolically afferents and improved neurocardiovascular responses to muscle metaboreflex activation, others reported unaltered responses. This narrative review aimed to: (a) highlight the current evidence on the effects of exercise training upon cardiovascular and autonomic responses to muscle metaboreflex activation; (b) analyze the role of training components and indicate potential mechanisms of metaboreflex adaptations; and (c) address key methodological features for future research. Though limited, accumulated evidence suggests that muscle metaboreflex adaptations depend on the individual clinical status, exercise modality, and training duration. In healthy populations, most trials negated the hypothesis of metaboreflex improvement due to chronic exercise, irrespective of the training duration. Favorable changes in patients with impaired metaboreflex, particularly chronic heart failure, mostly resulted from long-term interventions (> 16 weeks) including aerobic exercise of moderate to high intensity, performed in isolation or within multimodal training. Potential mechanisms of metaboreflex improvements include enhanced sensitivity of channels and receptors, greater antioxidant capacity, lower metabolite accumulation, increased functional sympatholysis, and muscle perfusion. Future research should investigate: (1) the dose-response relationship of training components within different exercise modalities to elicit improvements in individuals showing intact or impaired muscle metaboreflex; and (2) potential and specific underlying mechanisms of metaboreflex improvements in individuals with different medical conditions.

Exercise training improves microvascular function in patients with Chagas heart disease: Data from the PEACH study.

BACKGROUND: Chagas heart disease (CHD) impairs the systemic microvascular function. We investigated the effects of exercise training on cutaneous microvascular function among patients with CHD. METHODS: Patients from the PEACH study were randomly assigned to a supervised exercise training 3 times/week for 6 months (Trained; n = 10) or a control group (Untrained; n = 8). Both groups underwent evaluation of microvascular function before, and at 3- and 6-months of follow-up. Cutaneous vascular conductance (CVC) was assessed in the skin of the forearm using laser speckle contrast imaging coupled with iontophoresis of acetylcholine (ACh), sodium nitroprusside (SNP) and during post-occlusive reactive hyperemia (PORH). RESULTS: At 3-months of follow-up, no difference was detected between groups in CVC responses to ACh (p = 0.50), SNP (p = 0.26) and HRPO (p = 0.65). However, at 6-months of follow-up, trained vs. untrained patients improved CVC induced by SNP-iontophoresis (0.19 ± 0.10 vs. 0.14 ± 0.15 APU.mmHg-1; p = 0.05) and PORH (0.63 ± 0.15 vs. 0.48 ± 0.18 APU.mmHg-1; p = 0.05). CVC response to ACh-iontophoresis was similar between groups (0.19 ± 0.11 vs. 0.22 ± 0.17 APU.mmHg-1; p = 0.38). CONCLUSION: Exercise training performed during 6 months improved the cutaneous microvascular function of CHD patients. Further studies evaluating the mechanism involved in this response are warranted.

Physical activity among women of low socioeconomic status living with HIV in two major cities of Brazil and Mozambique: A cross-sectional comparative study.

OBJECTIVES: Physical activity (PA) may reduce cardiovascular risk and preserve functional capacity of people living with human immunodeficiency virus (HIV). However, only limited research objectively measured PA in patients with low socioeconomic status (SES) in low-income countries, particularly in South America and sub-Saharan Africa. This study compared the PA assessed by accelerometers in women of low SES living with HIV under common antiretroviral therapy (cART) from two major cities in Brazil (Rio de Janeiro, n=33; 40.1±6.1 years) and Mozambique (Maputo, n=50; 38.8±8.7 years). METHODS: Eligible women wore triaxial accelerometers during seven consecutive days, to estimate their habitual PA and daily energy expenditure. RESULTS: The proportion of participants with overweight/obesity was greater in Rio than Maputo (57% vs. 30%; p=0.021), as well as those classified as sedentary based on steps/day (45% vs. 22%; p=0.02). Sedentary time was prevalent (Median±IQD: Rio-1236±142 vs. Maputo-1192±135 min/day; p=0.15). Time spent in PA was short, but Brazilians exhibited lower amount of light (111±56 vs. 145±51 min/day; p<0.001) and moderate-to-vigorous PA (88±3 vs. 64±36 min/day; p=0.001) vs. Mozambicans. The proportion of patients performing 60 min/day of moderate-to-vigorous PA were 58% (Rio) and 82% (Maputo), respectively. Despite of this, estimated daily energy expenditure was equivalent in both groups (1976±579 vs. 1933±492 kcal; p=0.731). CONCLUSIONS: Women with low SES living with HIV in Maputo were more active vs. patients from Rio de Janeiro. Albeit sedentary behavior was prevalent, the proportion of patients complying with the minimum recommended PA for health was higher than values usually reported in developed countries.

Effects of short-term high-intensity interval and continuous exercise training on body composition and cardiac function in obese sarcopenic rats.

AIM: We investigated the effects of high-intensity interval and continuous short-term exercise on body composition and cardiac function after myocardial ischemia-reperfusion injury (IRI) in obese rats. METHODS: Rats fed with a standard chow diet (SC) or high-fat diet (HFD) for 20 weeks underwent systolic blood pressure (SBP), glycemia and dual-energy X-ray absorptiometry analyses. Then, animals fed with HFD were subdivided into three groups: sedentary (HFD-SED); moderate-intensity continuous training (HFD-MICT); and high-intensity interval training (HFD-HIIT). Exercised groups underwent four isocaloric aerobic exercise sessions, in which HFD-MICT maintained the intensity continuously and HFD-HIIT alternated it. After exercise sessions, all groups underwent global IRI and myocardial infarct size (IS) was determined histologically. Fat and muscle mass were weighted, and protein levels involved in muscle metabolism were assessed in skeletal muscle. RESULTS: HFD-fed versus SC-fed rats reduced lean body mass by 31% (P < 0.001), while SBP, glycemia and body fat percentage were increased by 10% (P = 0.04), 30% (P = 0.006) and 54% (P < 0.001); respectively. HFD-induced muscle atrophy was restored in exercised groups, as only HFD-SED presented lower gastrocnemius (32%; P = 0.001) and quadriceps mass (62%; P < 0.001) than SC. PGC1-α expression was 2.7-fold higher in HFD-HIIT versus HFD-SED (P = 0.04), whereas HFD-HIIT and HFD-MICT exhibited 1.7-fold increase in p-mTORSer2481 levels compared to HFD-SED (P = 0.04). Although no difference was detected among groups for IS (P = 0.30), only HFD-HIIT preserved left-ventricle developed pressure after IRI (+0.7 mmHg; P = 0.9). SIGNIFICANCE: Short-term exercise, continuous or HIIT, restored HFD-induced muscle atrophy and increased mTOR expression, but only HIIT maintained myocardial contractility following IRI in obese animals.

Physical activity among women of low socioeconomic status living with HIV in two major cities of Brazil and Mozambique: A cross-sectional comparative study

OBJECTIVES: Physical activity (PA) may reduce cardiovascular risk and preserve functional capacity of people living with human immunodeficiency virus (HIV). However, only limited research objectively measured PA in patients with low socioeconomic status (SES) in low-income countries, particularly in South America and sub-Saharan Africa. This study compared the PA assessed by accelerometers in women of low SES living with HIV under common antiretroviral therapy (cART) from two major cities in Brazil (Rio de Janeiro, n=33; 40.1±6.1 years) and Mozambique (Maputo, n=50; 38.8±8.7 years). METHODS: Eligible women wore triaxial accelerometers during seven consecutive days, to estimate their habitual PA and daily energy expenditure. RESULTS: The proportion of participants with overweight/obesity was greater in Rio than Maputo (57% vs. 30%; p=0.021), as well as those classified as sedentary based on steps/day (45% vs. 22%; p=0.02). Sedentary time was prevalent (Median±IQD: Rio-1236±142 vs. Maputo-1192±135 min/day; p=0.15). Time spent in PA was short, but Brazilians exhibited lower amount of light (111±56 vs. 145±51 min/day; p<0.001) and moderate-to-vigorous PA (88±3 vs. 64±36 min/day; p=0.001) vs. Mozambicans. The proportion of patients performing 60 min/day of moderate-to-vigorous PA were 58% (Rio) and 82% (Maputo), respectively. Despite of this, estimated daily energy expenditure was equivalent in both groups (1976±579 vs. 1933±492 kcal; p=0.731). CONCLUSIONS: Women with low SES living with HIV in Maputo were more active vs. patients from Rio de Janeiro. Albeit sedentary behavior was prevalent, the proportion of patients complying with the minimum recommended PA for health was higher than values usually reported in developed countries.

Exercise-induced cardiac opioid system activation attenuates apoptosis pathway in obese rats.

AIM: To compare the effect of 150 min vs. 300 min of weekly moderate intensity exercise training on the activation of the opioid system and apoptosis in the hearts of a diet-induced obesity model. METHODS: Male Wistar rats were fed with either control (CON) or high fat (HF) diet for 32 weeks. At the 20th week, HF group was subdivided into sedentary, low (LEV, 150 min·week-1) or high (HEV, 300 min·week-1) exercise volume. After 12 weeks of exercise, body mass gain, adiposity index, systolic blood pressure, cardiac morphometry, apoptosis biomarkers and opioid system expression were evaluated. RESULTS: Sedentary animals fed with HF presented pathological cardiac hypertrophy and higher body mass gain, systolic blood pressure and adiposity index than control group. Both exercise volumes induced physiological cardiac hypertrophy, restored systolic blood pressure and improved adiposity index, but only 300 min·week-1 reduced body mass gain. HF group exhibited lower proenkephalin, PI3K, ERK and GSK-3ß expression, and greater activated caspase-3 expression than control group. Compared to HF, no changes in the cardiac opioid system were observed in the 150 min·week-1 of exercise training, while 300 min·week-1 showed greater proenkephalin, DOR, KOR, MOR, Akt, ERK and GSK-3ß expression, and lower activated caspase-3 expression. CONCLUSION: 300 min·week-1 of exercise training triggered opioid system activation and provided greater cardioprotection against obesity than 150 min·week-1. Our findings provide translational aspect with clinical relevance about the critical dose of exercise training necessary to reduce cardiovascular risk factors caused by obesity.

Institutional Guidelines for Resistance Exercise Training in Cardiovascular Disease: A Systematic Review.

BACKGROUND: Institutional position stands are useful for practitioners when designing exercise routines for specific populations. Resistance training has been included in programs for patients with cardiovascular disease. OBJECTIVE: The objective of this systematic review was to analyze institutional guidelines providing recommendations for resistance training applied to cardiovascular disease. METHODS: PubMed, Web of Science, and Scopus databases were searched from inception until 30 April, 2018. RESULTS: Of 994 articles initially found, 13 position stands were retained. Consensual indications occurred only for number of sets (one to three sets) and training frequency (two to three sessions/week). Recommendations concerning other major training variables were discordant regarding workload (none or loads ranging from < 30% up to 80% 1 repetition maximum) and exercise order (none or vaguely indicating alternation of muscle groups or circuit format), or insufficient regarding intervals between sets and exercises or number and type of exercises. Overall, guidelines lack recommendations of specific procedures for each type of disease at different severity levels, cardiovascular risk during exercise, or criteria for training progression. CONCLUSIONS: Recommendations provided by institutional guidelines appear to be insufficient to support adequate resistance training prescription in the context of cardiovascular disease.

Influence of Physical Exercise on Advanced Glycation End Products Levels in Patients Living With the Human Immunodeficiency Virus.

Introduction: Combined antiretroviral therapy (cART) used to treat acquired immunodeficiency virus (HIV) induces a number of adverse effects, such as insulin resistance and dyslipidemia, which ultimately increases the cardiovascular risk. Advanced glycation end products (AGEs) have been implicated in the etiology of cardiovascular diseases, diabetes and other chronic diseases. It is known that physical exercise improves the lipid profile, insulin resistance and reduces the risk of cardiovascular diseases. However, the impact of physical exercise on AGE levels in HIV-infected patients has not been so far investigated. Therefore, this study compared AGEs levels in people with and without HIV and verified the effect of physical training on serum AGE levels. Methods: Participants were initially assigned into three groups: healthy control (CTL, n = 35), physically inactive HIV-infected (In-HIV, n = 33) and physically active HIV-infected (Ac-HIV, n = 19). The In-HIV group underwent physical training for 3 months, consisting of 60-min sessions of multimodal supervised exercise (aerobic, resistance and flexibility) with moderate intensity (50-80% heart rate reserve), performed 3 times/week. AGEs were measured in serum by fluorescence spectrometry. Results: At baseline, serum AGEs fluorescence level was significantly higher in inactive HIV-patients when compared to controls or active HIV-patients (In-HIV: 0.93 ± 0.08 vs. controls: 0.68 ± 0.13 and Ac-HIV: 0.59 ± 0.04 A.U.; P < 0.001). Triglycerides were also higher in In-HIV than CTL (182.8 ± 102 vs. 132.8 ± 52.3 mg/dL; P < 0.05). Waist circumference was lower in Ac-HIV, compared to In-HIV and controls (83.9 ± 10.4 vs. 92.9 ± 13.5 and 98.3 ± 12.4, respectively; P < 0.05). Body mass, fasting blood glucose, LDL, HDL, and total cholesterol were similar between groups. After training, AGE levels decreased (Baseline: 0.93 ± 0.08 vs. 3 months follow-up: 0.59 ± 0.04 AU; P < 0.001), no further difference being detected vs. CTL or Ac-HIV. Conclusion: HIV-infected patients under cART exhibited elevated AGEs levels compared to healthy individuals and physically active patients. Short-term aerobic training of moderate intensity counteracted this condition.

Is endothelial microvascular function equally impaired among patients with chronic Chagas and ischemic cardiomyopathy?

BACKGROUND: Chronic Chagas cardiomyopathy (CCC) and cardiomyopathies due to other etiologies involve differences in pathophysiological pathways that are still unclear. Systemic microvascular abnormalities are associated with the pathogenesis of ischemic heart disease. However, systemic microvascular endothelial function in CCC remains to be elucidated. Thus, we compared the microvascular endothelial function of patients presenting with CCC to those with ischemic cardiomyopathy disease. METHODS: Microvascular reactivity was assessed in 21 patients with cardiomyopathy secondary to Chagas disease, 21 patients with cardiomyopathy secondary to ischemic disease and 21 healthy controls. Microvascular blood flow was assessed in the skin of the forearm using laser speckle contrast imaging coupled with iontophoresis of acetylcholine (ACh). RESULTS: Peak increase in forearm blood flow with ACh iontophoresis in relation to baseline was greater in healthy controls than in patients with heart disease (controls: 162.7 ±â€¯58.4% vs. ischemic heart disease: 74.1 ±â€¯48.3% and Chagas: 85.1 ±â€¯68.1%; p < 0.0001). Patients with Chagas and ischemic cardiomyopathy presented similar ACh-induced changes from baseline in skin blood flow (p = 0.55). CONCLUSION: Endothelial microvascular function was equally impaired among patients with CCC and ischemic cardiomyopathy.

Cardiac Ischemia/Reperfusion Injury: The Beneficial Effects of Exercise.

Cardiac ischemia reperfusion injury (IRI) occurs when the myocardium is revascularized after an episode of limited or absent blood supply. Many changes, including free radical production, calcium overload, protease activation, altered membrane lipids and leukocyte activation, contribute to IRI-induced myocardium damage. Aerobic exercise is the only countermeasure against IRI that can be sustained on a regular basis in clinical practice. Interestingly, both short-term (3-5 days) and long-term (several weeks) exercise increase myocardial tolerance, reduce infarct size area and arrhythmias induced by IRI. Exercise protects the heart against IRI in a biphasic manner. The early phase of cardioprotection occurs between 30 min and 3 h following an acute exercise bout, whilst the late phase is achieved within 24 h after the exercise bout and persists for several days. As for the exercise intensity, although controversial data exists, it is feasible that the amount of cardioprotection is proportional to exercise intensity and only achieved above a critical threshold. It is known that aerobic exercise produces a cardioprotective phenotype, however the mechanisms responsible for this phenomenon remain unclear. Apparently, aerobic exercise-induced preconditioning is dependent on several factors that work together to protect the heart. Altered nitric oxide (NO) signaling, increased levels of heat shock proteins (HSPs), enhanced function of ATP-sensitive potassium channels, increased activation of opioids system, and enhanced antioxidant capacity may contribute to exercise-induced cardioprotection. Much has been discovered from animal models involving exercise-induced cardioprotection against cardiac IRI, however translating these findings to clinical practice still represents the major challenge in this field.

The impact of early aerobic exercise on brain microvascular alterations induced by cerebral hypoperfusion.

The therapeutic potential of early exercise training following cerebral hypoperfusion was investigated on brain perfusion and inflammation in rats with permanent bilateral occlusion of the common carotid arteries (2VO). Wistar rats were subjected to 2VO or sham surgery and each group was then subdivided randomly into sedentary or exercise groups. Early exercise training was initiated after three days of 2VO or sham surgery and consisted of seven days of treadmill training (30min/day at ∼60% of maximal exercise test), composing four groups: 1) Sham sedentary (Sham-Sed), 2) Sham exercised (Sham-Ex), 3) 2VO sedentary (2VO-Sed) and 4) 2VO exercised (2VO-Ex). Microvascular cerebral blood flow (MCBF) and NADPH oxidase and eNOS gene expression were evaluated by laser speckle contrast imaging and RT-PCR, respectively, and brain functional capillary density and endothelial-leukocyte interactions were evaluated by fluorescence intravital video-microscopy. The 2VO-Sed group presented a decrease in MCBF (Sham-Sed: 230.9±12.2 vs. 2VO-Sed: 183.6±10.6 arbitrary perfusion units, P<0.05) and in functional capillary density (Sham-Sed: 336.4±25.3 vs. 2VO-Sed: 225.5±28.1capillaries/mm2, P<0.05). Early intervention with physical exercise was able to prevent the cerebral microvascular inflammation by decreasing endothelial-leukocyte interactions (2VO-Ex: 0.9±0.3 vs. 2VO-Sed: 5±0.6cells/min/100µm, P<0.0001) and reducing brain NADPH oxidase gene expression (2VO-Ex: 1.7±0.1 arbitrary units, P<0.05). Cerebral microcirculatory and inflammatory alterations appear to be triggered during the first days after 2VO surgery, and early intervention with physical exercise may represent a means of preventing the microvascular alterations induced by chronic cerebral hypoperfusion.