Inspiratory muscle training in addition to conventional physical rehabilitation in hospitalized patients undergoing hematopoietic stem cell transplantation: a randomized controlled trial.

PURPOSE: To investigate the effect of inspiratory muscle training (IMT) in addition to conventional physical rehabilitation on muscle strength, functional capacity, mobility, hemodynamics, fatigue, and quality of life in hospitalized patients undergoing hematopoietic stem cell transplantation (HSCT). METHODS: We conducted a randomized controlled trial in 57 inpatients with hematological diseases undergoing HSCT. Conventional inpatient physical rehabilitation was delivered to the IMT (n = 27) and control (CON; n = 30) groups according to usual care, and the first group additionally performed IMT. The IMT was prescribed according to clinical and laboratory parameters at 40% of maximal inspiratory pressure (MIP), 5 days/week throughout the hospitalization, in sessions of 10-20 min. The primary outcome was MIP and the secondary outcomes were maximal expiratory pressure (MEP), peripheral muscle strength (handgrip and sit-to-stand tests), functional capacity (6-min step test), mobility (timed up and go test), blood pressure, quality of life (EORTC-QLQ-C30), and fatigue (FACT-F) at admission and hospital discharge. RESULTS: The population was predominately autologous HSCT. The IMT group significantly increased the MIP (P < 0.01) and decreased both fatigue (P = 0.01) and blood pressure (P < 0.01) compared with control. No differences were found between admission and hospital discharge in peripheral and expiratory muscle strength, functional capacity, mobility, and quality of life in both groups (P > 0.05). CONCLUSIONS: Our results support the effectiveness of IMT as part of rehabilitation for HSCT inpatients, improving inspiratory muscle strength, and reducing fatigue and blood pressure. TRIAL REGISTRATION: NCT03373526 (clinicaltrials.gov).

Exacerbated hemodynamic response during exercise in cancer patients prior to autologous hematopoietic stem cell transplantation.

PURPOSE: Chemotherapy treatment can lead to cardiovascular toxicity and physical impairment prior to autologous hematopoietic stem cell transplantation (auto-HSCT). Cardiovascular adjustments during exercise and the exercise capacity remain unknown in patients prior to auto-HSCT. Thus, the hemodynamic responses during exercise and exercise capacity were evaluated using a novel effort test in patients prior to auto-HSCT. METHODS: Thirty patients prior to auto-HSCT (BMT group: 44.6 ± 14.1 years) and 23 control participants (CON group: 43.9 ± 16.6 years) performed the 6-Minute Step Test (6MST) to assess their exercise capacity and the hemodynamic responses during exercise. Systolic and diastolic blood pressure (SBP and DBP), heart rate (HR), and oxygen saturation (SpO2) were measured during the test. Rate-pressure product (RPP) was calculated multiplying SBP by HR. The highest HR value recorded during the test was compared with the maximum HR predicted by age and was used as % of maximum HR (%HRmax). RESULTS: The number of steps up and down performed by the BMT group was lower than CON (108.8 ± 25.3 vs. 127.5 ± 34.4 steps, P = 0.02). The BMT group showed a higher magnitude of increase in SBP and RPP during the 6MST when compared to CON (ΔSBP: 18.5 ± 11.45 vs. 8.30 ± 18.46 mmHg, P = 0.01; and ΔRPP: 8197.3 ± 3829.1 vs. 6170.9 ± 3568.9 mmHg beats min-1, P = 0.05). The BMT group exhibited higher SpO2 and HR values throughout the protocol (P < 0.05), reaching a higher %HRmax than CON group (76.9 ± 9.6 vs. 66.4 ± 8.9%, P < 0.01). CONCLUSIONS: Patients with indication for auto-HSCT have exacerbated chronotropic and pressor responses during exercise and reduced exercise capacity in the 6MST.

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.

Ischemic Preconditioning Improves Resistance Training Session Performance.

ABSTRACT: da Silva Novaes, J, da Silva Telles, LG, Monteiro, ER, da Silva Araujo, G, Vingren, JL, Silva Panza, P, Reis, VM, Laterza, MC, and Vianna, JM. Ischemic preconditioning improves resistance training session performance. J Strength Cond Res 35(11): 2993-2998, 2021-The aim of this study was to investigate the acute effect of ischemic preconditioning (IPC) in a resistance exercise (RE) training session on the number of repetitions performed, total volume, and rating of perceived exertion in recreationally trained and normotensive men. Sixteen recreationally trained and normotensive men completed 3 RE sessions in a counterbalanced and randomized order: (a) IPC protocol using 220 mm Hg followed by RE (IPC), (b) IPC cuff control protocol with 20 mm Hg followed by RE (CUFF), and (c) no IPC (control) followed by RE (CON). RE was performed with 3 sets of each exercise (bench press, leg press, lateral pulldown, hack machine squat, shoulder press, and Smith back squat) until concentric muscular failure, at 80% of one repetition maximum, with 90 seconds of rest between sets and 2 minutes of rest between exercises. Ischemic preconditioning and CUFF consisted of 4 cycles of 5 minutes of occlusion/low pressure alternating with 5 minutes of no occlusion (0 mm Hg) using a pneumatic tourniquet applied around the subaxillary region of the upper arm. For each condition, the number of repetitions completed, total volume of work performed, and rating of perceived exertion were determined. No significant difference was found for rating of perceived exertion between any experimental protocol. Ischemic preconditioning significantly (p < 0.05) increased the number of repetitions across exercises. Consequently, total volume performed (sum of total number of repetitions x load for each exercise) was significantly higher in IPC (46,170 kg) compared with CON (34,069 kg) and CUFF (36,590 kg) across all exercises. This work may have important implications for athletic populations because it demonstrates increase in muscle performance outcomes during a single RE session. Therefore, performing IPC before RE could be an important exercise prescription recommendation to increase maximum repetition performance and total volume of work performed and thus potentially increase desired training adaptations (i.e., strength and hypertrophy).

Safety and feasibility of inspiratory muscle training for hospitalized patients undergoing hematopoietic stem cell transplantation: a randomized controlled study.

PURPOSE: Patients undergoing hematopoietic stem cell transplantation (HSCT) usually experienced respiratory muscle weakness. Inspiratory muscle training (IMT) at HSCT has not been studied yet. Thus, it is important to evaluate the safety, feasibility, and preliminary effectiveness of IMT for hospitalized patients undergoing HSCT with an unstable and acute clinical condition. METHODS: This is a randomized controlled feasibility study. Thirty-one hospitalized patients undergoing HSCT were randomized to the conventional physical rehabilitation (CON) or to the IMT group (conventional physical rehabilitation + IMT). IMT was carried out at 40% of maximal inspiratory pressure (MIP), 5 sessions weekly, 10-20 min/session. Primary outcomes were safety and feasibility (recruitment, adherence, and attrition rates) of IMT. Secondary outcomes were respiratory strength, respiratory rate, oxygen saturation, and frequency of patients with oxygen desaturation, bleeding, dyspnea, and acute pulmonary edema. RESULTS: Patients were allocated to the IMT (N = 15; 43.6 years) or to the CON group (N = 16; 46.6 years). The recruitment rate was 100%, the adherence rate was 91%, and attrition was 13% to IMT. Two events were observed in 126 IMT sessions (1.5%). MIP increased in the IMT group (P < 0.01). No differences were observed in respiratory rate and oxygen saturation between groups. Trends to negative outcomes were observed in the CON in comparison to IMT group for a need of oxygen therapy (18% vs. 6%), bleeding (12% vs. 6%), dyspnea (25% vs. 13%), and acute pulmonary edema (6% vs. 0%). CONCLUSIONS: IMT is safe, feasible, and improves the inspiratory muscle strength in hospitalized patients undergoing HSCT. TRIAL REGISTRATION: Clinical trial registration: NCT03373526.

Baroreflex gain and vasomotor sympathetic modulation in resistant hypertension.

PURPOSE: The aim of this study was to determine the gain and latency of arterial baroreflex control of heart rate in patients with resistant hypertension compared to patients with essential hypertension and normotensive subjects. METHODS: Eighteen patients with resistant hypertension (56 ± 10 years, mean of four antihypertensive drugs), 17 patients with essential hypertension (56 ± 11 years, mean of two antihypertensive drugs), and 17 untreated normotensive controls (50 ± 15 years) were evaluated by spectral analysis of the spontaneous fluctuations of arterial pressure (beat-to-beat) and heart rate (ECG). This analysis estimated vasomotor and cardiac autonomic modulations, respectively. The transfer function analysis quantified the gain and latency of the response of output signal (RR interval) per unit of spontaneous change of input signal (systolic arterial pressure). RESULTS: The gain was similarly lower in patients with resistant hypertension and patients with essential hypertension in relation to normotensive subjects (4.67 ± 2.96 vs. 6.60 ± 3.30 vs. 12.56 ± 8.81 ms/mmHg; P < 0.01, respectively). However, the latency of arterial baroreflex control of heart rate was significantly higher only in patients with resistant hypertension when compared to patients with essential hypertension and normotensive subjects (-4.01 ± 3.19 vs. -2.91 ± 2.10 vs. -1.82 ± 1.09 s; P = 0.04, respectively). In addition, the index of vasomotor sympathetic modulation was significantly increased only in patients with resistant hypertension when compared to patients with essential hypertension and normotensive subjects (4.04 ± 2.86 vs. 2.65 ± 1.88 vs. 2.06 ± 1.70 mmHg2; P < 0.01, respectively). CONCLUSIONS: Patients with resistant hypertension have reduced gain and increased latency of arterial baroreflex control of heart rate. These patients also have increased vasomotor sympathetic modulation.

Cardiac Autonomic Dysfunction in Offspring of Hypertensive Parents During Exercise.

Offspring of hypertensive parents present autonomic dysfunction at rest and during physiological maneuvers. However, the cardiac autonomic modulation during exercise remains unknown. This study tested whether the cardiac autonomic modulation would be reduced in offspring of hypertensive parents during exercise. Fourteen offspring of hypertensive and 14 offspring of normotensive individuals were evaluated. The groups were matched by age (24.5±1.0 vs. 26.6±1.5 years; p=0.25) and BMI (22.8±0.6 vs. 24.2±1.0 kg/m2; p=0.30). Blood pressure and heart rate were assessed simultaneously during 3 min at baseline followed by 3-min isometric handgrip at 30% of maximal voluntary contraction. Cardiac autonomic modulation was evaluated using heart rate variability. Primary variables were subjected to two-way ANOVA (group vs. time). P value<0.05 was considered statistically significant. Blood pressure and heart rate were similar between groups during exercise protocol. In contrast, offspring of hypertensive subjects showed a reduction of SDNN (Basal=34.8±3.5 vs. 45.2±3.7 ms; Exercise=30.8±3.3 vs. 41.5±3.9 ms; p group=0.01), RMSSD (Basal=37.1±3.7 vs. 52.0±6.0 ms; Exercise=28.6±3.4 vs. 41.9±5.3 ms; p group=0.02) and pNN50 (Basal=15.7±4.0 vs. 29.5±5.5%; Exercise=7.7±2.4 vs. 18.0±4.3%; p group=0.03) during the exercise protocol in comparison with offspring of normotensive parents. We concluded that normotensive offspring of hypertensive parents exhibit impaired cardiac autonomic modulation during exercise.

Acute effect of ultramarathon on systolic and diastolic cardiac function: Systematic review and meta-analysis.

BACKGROUND: Ultramarathon running poses physiological challenges, impacting cardiac function. This systematic review and meta-analysis explore the acute effects of single-stage ultramarathon running on cardiac function. METHODS: Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations were followed. Searches covered Medline, Embase, CINAHL, SPORTDiscus, Web of Science, Central Cochrane, and Scopus. Random effects meta-analyses assessed left ventricular (LV) and right ventricular (RV) variables, expressed as mean differences (MD) with 95% confidence intervals (CI). RESULTS: Among 6972 studies, 17 were included. Post-ultramarathon reductions were found in LV end-diastolic diameter (LVEDD) (-1.24; 95% CI = -1.77, -0.71 mm), LV end-diastolic volume (LVEDV) (-9.92; 95% CI = -15.25, -4.60 ml), LV stroke volume (LVSV) (-8.96 ml, 95% CI -13.20, -4.72 ml), LV ejection fraction (LVEF) (-3.71; 95% CI = -5.21, -2.22%), LV global longitudinal strain (LVGLS) (-1.48; 95% CI = -2.21, -0.76%), E/A (-0.30; 95% CI = -0.38, -0.22 cm/s), .E' (-1.35 cm/s, 95% CI -1.91, -0.79 cm/s), RV fractional area change (RVFAC) (-3.34, 95% CI = -5.84, -0.84%), tricuspid annular plane systolic excursion (TAPSE) (-0.12, 95% CI = -0.22, -0.02 cm), RV global longitudinal strain (RVGLS) (-1.73, 95% CI = -2.87, -0.59%), with increases in RV end-diastolic area (RVEDA) (1.89, 95% CI = 0.63, 3.14 cm2), RV Peak A' (1.32 cm/s, 95% CI 0.20, 2.44), and heart rate (18.24, 95% CI = 15.16, 21.32). No significant differences were observed in LV end-systolic diameter (LVESD), LV end-systolic volume (LVESV), RV end-diastolic diameter (RVEDD), RV Peak E', and RV Peak S'. CONCLUSIONS: Evidence suggests immediate impairment of systolic and diastolic cardiac function post-ultramarathon running.

High-dose Chemotherapy Impairs Cardiac Autonomic Control of Hospitalized Cancer Patients Undergoing Autologous Hematopoietic Stem Cell Transplantation.

BACKGROUND: Autologous hematopoietic stem cell transplantation (HSCT) patients have intermediary and late cardiac autonomic dysfunction, which is an independent mortality predictor. However, it is unknown when this HSCT-related autonomic dysfunction begins during hospitalization for HSCT and whether cardiac autonomic control (CAC) is related to cardiotoxicity in these patients. PATIENTS AND METHODS: CAC was assessed in 36 autologous-HSCT inpatients (HSCT group) and 23 cancer-free outpatients (CON group) using heart rate variability analysis. The HSCT group was assessed at five time-points from admission to hospital discharge during hospitalization period. The CON group was assessed once. The severity of cardiotoxicity (CTCAE 5.0) and cardiac troponin I were recorded. RESULTS: The CAC was significantly reduced after high-dose chemotherapy (HDC) (reduction of MNN, SDNN, RMSSD, LFms2 and HFnu, and increase of LFnu and LF/HF; P<0.05). At the onset of neutropenia, pNN50 and HFms2 were also reduced (P<0.05) compared to the admission ones. Although both groups were similar regarding CAC at hospital admission, the HSCT patients showed impaired CAC at hospital discharge (P<0.05). The LF/HF was positively associated with cardiac troponin I and RMSSD was inversely associated with the severity of cardiotoxicity (P≤0.05). CONCLUSION: CAC worsened during hospitalization for autologous-HSCT, mainly after HDC. In addition, it seems associated to early signs of cardiotoxicity in these patients.

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.

REDUCED PERIPHERAL AND INSPIRATORY MUSCLE ENDURANCE IN PATIENTS WITH LIVER CIRRHOSIS: A CROSS-SECTIONAL STUDY.

BACKGROUND: Liver cirrhosis (LC) causes several musculoskeletal changes. OBJECTIVE: To test the hypothesis that the peripheral and inspiratory muscle endurance are reduced in patients with liver cirrhosis. METHODS: Twenty-one patients with LC (LC group; 61±14 years) and 18 age-matched subjects (control group; 56±17 years) had accepted to participate in this cross-sectional observational study. To assess peripheral muscle endurance, all volunteers performed a rhythmic handgrip exercise at 45% of their maximum voluntary contraction. A metronome was used to control the contraction-relaxation cycles at 60/min. The inspiratory muscle endurance was assessed using PowerBreath®. Participants underwent inspiratory muscle exercise at 60% of their maximal inspiratory muscle strength. The time until failure characterized the muscle endurance for both handgrip and inspiratory muscle exercises. Additionally, the quality of life of the participants was assessed. RESULTS: The muscle endurance was lower in the LC group when compared to the control group for both handgrip (67 vs 130 s, P<0.001) and inspiratory muscle exercises (40 vs 114 s, P<0.001). The peripheral muscle endurance was directly correlated with the total quality of life score (r=0.439, P=0.01) and to the following domains: fatigue (r=0.378 e P=0.030), activity (r=0.583, P=0.001), systemic symptoms (r=0.316, P=0.073) and preoccupation (r=0.370, P=0.034). The inspiratory muscle endurance was inversely correlated with the total quality of life score (r=0.573, P=0.001) and the following domains: fatigue (r=0.503, P=0.002), activity (r=0.464, P=0.004), systemic symptoms (r=0.472, P=0.004), abdominal symptoms (r=0.461, P=0.005), emotional function (r=0.387, P=0.02) and preoccupation (r=0.519, P=0.001). CONCLUSION: Both peripheral and inspiratory muscle endurance were lower in LC patients when compared to the control group.

Blunted blood pressure response to exercise and isolated muscle metaboreflex activation in patients with cirrhosis.

We sought to test the hypothesis that the cardiovascular responses to isolated muscle metaboreflex activation would be blunted in patients with cirrhosis. Eleven patients with cirrhosis and 15 healthy controls were evaluated. Blood pressure (BP; oscillometric method), contralateral forearm blood flow (FBF; venous occlusion plethysmography), and heart rate (HR; electrocardiogram) were measured during baseline, isometric handgrip at 30% of maximal voluntary contraction followed by postexercise ischemia (PEI). Forearm vascular conductance (FVC) was calculated as follows: (FBF / mean BP) × 100. Changes in HR during handgrip were similar between groups but tended to be different during PEI (controls: Δ 0.5 ± 1.1 bpm vs. cirrhotic patients: Δ 3.6 ± 1.0 bpm, P = 0.057). Mean BP response to handgrip (controls: Δ 20.9 ± 2.7 mm Hg vs. cirrhotic patients: Δ 10.6 ± 1.5 mm Hg, P = 0.006) and PEI was attenuated in cirrhotic patients (controls: Δ 16.1 ± 1.9 mm Hg vs. cirrhotic patients: Δ 7.2 ± 1.4 mm Hg, P = 0.001). In contrast, FBF and FVC increased during handgrip and decreased during PEI similarly between groups. These results indicate that an abnormal muscle metaboreflex activation explained, at least partially, the blunted pressor response to exercise exhibited by cirrhotic patients. Novelty: Patients with cirrhosis present abnormal muscle metaboreflex activation. BP response was blunted but forearm vascular response was preserved. HR response was slightly elevated.

Six-Minute Walking Test as a Predictor of Clinical Decompensation in Patients with Cirrhosis.

BACKGROUND AND AIMS: The 6-minute walk test (6MWT) is a measure of the overall functional capacity and is associated with the risk of mortality in patients with liver cirrhosis and in those listed for liver transplantation. Nevertheless, physical performance has not yet been established as a predictor of the risk of clinical decompensation in patients with cirrhosis. We aimed to determine the capacity of the 6MWT to predict the clinical decompensation in patients with cirrhosis after 1 year of follow-up. METHODS: This prospective cohort study included patients with compensated cirrhosis of several etiologies. All participants had stable clinical conditions for at least 6 months prior to baseline. At baseline, patients performed the 6MWT and were followed up for 1 year to detect the decompensation outcomes. RESULTS: A total of 55 participants completed the evaluation and follow-up. The mean age was 56.3±10.5 years, and 65% were men. Around 65.4% were classified as Child-Pugh class A. In the receiver operating characteristic analysis, a walking distance ≤ 401.8 m during the 6MWT was set as the threshold for predicting clinical decompensation with 64% sensitivity and 82% specificity. Kaplan-Meier curve analysis revealed that patients who covered a distance of < 401.8 m during the test had a decompensation-free outcome rate of 30% as compared to the rate of 75% of those who walked > 401.8 m (p<0.001). CONCLUSIONS: The 6MWT was a significant predictor of clinical decompensation in patients with cirrhosis. A cutoff of 401.8 m was related to an increased risk of clinical decompensation in cirrhotic patients with a stable clinical condition at baseline. The 6MWT should be added to the clinical assessment of the cirrhotic population.

Functional Capacity Change Impacts the Quality of Life of Hospitalized Patients Undergoing Hematopoietic Stem Cell Transplantation.

OBJECTIVE: The aim of the study was to compare the quality of life (QOL) of patients undergoing hematopoietic stem cell transplantation who improved their functional capacity during hospitalization (increased functional capacity group) with that of patients who maintained or decreased functional capacity during hospitalization (decreased functional capacity group). DESIGN: This observational, longitudinal study included 27 hospitalized patients undergoing hematopoietic stem cell transplantation. Patients were divided into increased functional capacity group (16 patients) and decreased functional capacity group (11 patients). Functional capacity (6-min step test), peripheral muscle strength (sit-to-stand test and handgrip strength), and QOL (European Organization for Research and Treatment of Cancer) were assessed at admission and at hospital discharge. RESULTS: Increased functional capacity patients had increased functional capacity and peripheral muscle strength of the lower and upper limbs at hospital discharge (P < 0.01, <0.01, and 0.02, respectively). The patients in the increased functional capacity group demonstrated an increase in global health and reduced symptoms at discharge (P = 0.02 and 0.03, respectively). No significant differences were observed between groups in the functional domain. CONCLUSIONS: Patients undergoing hematopoietic stem cell transplantation, who have improved functional capacity at discharge, also experience an improved QOL, with no such improvement noted among patients who have stable or reduced functional capacity. We recommend that the treatment protocol for hospitalized patients undergoing hematopoietic stem cell transplantation include an exercise program aimed at improving functional capacity.

Autonomic and Vascular Control in Prehypertensive Subjects with a Family History of Arterial Hypertension.

BACKGROUND: Individuals with a family history of systemic arterial hypertension (FHSAH) and / or prehypertension have a higher risk of developing this pathology. OBJECTIVE: To evaluate the autonomic and vascular functions of prehypertensive patients with FHSAH. METHODS: Twenty-five young volunteers with FHSAH, 14 normotensive and 11 prehypertensive subjects were submitted to vascular function evaluation by forearm vascular conductance(VC) during resting and reactive hyperemia (Hokanson®) and cardiac and peripheral autonomic modulation, quantified, respectively, by spectral analysis of heart rate (ECG) and systolic blood pressure (SBP) (FinometerPRO®). The transfer function analysis was used to measure the gain and response time of baroreflex. The statistical significance adopted was p ≤ 0.05. RESULTS: Pre-hypertensive individuals, in relation to normotensive individuals, have higher VC both at rest (3.48 ± 1.26 vs. 2.67 ± 0.72 units, p = 0.05) and peak reactive hyperemia (25, 02 ± 8.18 vs. 18.66 ± 6.07 units, p = 0.04). The indices of cardiac autonomic modulation were similar between the groups. However, in the peripheral autonomic modulation, greater variability was observed in prehypertensive patients compared to normotensive individuals (9.4 [4.9-12.7] vs. 18.3 [14.8-26.7] mmHg2; p < 0.01) and higher spectral components of very low (6.9 [2.0-11.1] vs. 13.5 [10.7-22.4] mmHg2, p = 0.01) and low frequencies (1.7 [1.0-3.0] vs. 3.0 [2.0-4.0] mmHg2, p = 0.04) of SBP. Additionally, we observed a lower gain of baroreflex control in prehypertensive patients compared to normotensive patients (12.16 ± 4.18 vs. 18.23 ± 7.11 ms/mmHg, p = 0.03), but similar delay time (-1.55 ± 0.66 vs. -1.58 ± 0.72 s, p = 0.90). CONCLUSION: Prehypertensive patients with FHSAH have autonomic dysfunction and increased vascular conductance when compared to normotensive patients with the same risk factor.

Hemodynamic responses during inspiratory muscle exercise in healthy young adults / Respuestas hemodinámicas durante el ejercicio de los músculos inspiratorios en adultos jóvenes sanos / Respostas hemodinâmicas durante exercício muscular inspiratório em jovens saudáveis

ABSTRACT The literature on hemodynamic responses during inspiratory muscle exercise (IME) lacks a consensus. To evaluate and compare hemodynamic responses during an IME session with and without resistive load, 15 sedentary men were subjected to two randomized IME sessions: one with 40% of maximal inspiratory pressure (IME 40%) and another without a resistive load (Sham), both of which were performed for two minutes over eight sessions with one-minute intervals. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), total peripheral resistance (TPR), stroke volume (SV), cardiac output (CO), and heart rate (HR) were measured by infrared digital photoplethysmography during five basal minutes and during the IME sessions. One-way analysis of variance and the Student's t test for paired data were used to analyze hemodynamic response and delta values between sessions. Effect size was evaluated by Cohen's D. A 5% significance level was adopted. SBP responses (sham: ∆−1±2 vs. 40%: ∆−4±2mmHg, p=0.27), DBP (sham: ∆2±1 vs. 40%: ∆1±2mmHg, p=0.60) and MBP (sham: ∆2±1 vs. 40%: ∆0±2mmHg, p=0.28) were similar between sessions. HR increases were higher in the 40% IME session than in the sham session (sham: ∆9±2 vs. 40%: ∆3±2bpm, p=0.001). SV only decreased during the sham session but responses were similar between sessions (sham: ∆−2±2 vs. IME 40%: ∆−6±2ml, p=0.13). Both sessions did not change SBP, DBP, MBP, CO, and TPR, but we observed a greater increase in HR in the IME 40% session. Only the Sham session decreased SV.

RESUMEN No hay consenso en la literatura sobre las respuestas hemodinámicas durante el ejercicio muscular inspiratorio (EMI). El objetivo de este estudio fue evaluar y comparar las respuestas hemodinámicas durante una sesión de EMI con y sin carga resistiva. Para ello, quince hombres sedentarios recibieron dos sesiones aleatorias de EMI: el 40% de la presión inspiratoria máxima (EMI 40%) y sin carga resistiva (sham), realizadas durante dos minutos, ocho sesiones y a intervalos de un minuto. La presión arterial sistólica (PAS), la presión arterial diastólica (PAD), la presión arterial media (PAM), la resistencia periférica total (RPT), el volumen sistólico (VS), el gasto cardíaco (GC) y la frecuencia cardíaca (FC) se midieron mediante fotopletismografía infrarroja digital durante cinco minutos al inicio y durante las sesiones de EMI. Se utilizaron ANOVA unidireccional y la prueba t de Student a datos emparejados para analizar la respuesta hemodinámica y los valores delta entre las sesiones. El tamaño del efecto se evaluó por el d de Cohen. El nivel de significancia adoptado fue de 5%. Las respuestas de PAS (sham: Δ−1±2 vs. 40%: ∆−4±2mmHg, p=0,27), PAD (sham: ∆2±1 vs. 40%: ∆1±2mmHg, p=0,60) y PAM (sham: ∆2±1 vs. 40%: ∆0±2mmHg, p=0,28) fueron similares entre las sesiones. El incremento de la FC fue mayor en la sesión de EMI 40% comparada con la sesión sham (sham: Δ9±2 vs. 40%: ∆3±2bpm, p=0,001). El VS tuvo una disminución exclusiva durante la sesión sham, pero la respuesta fue similar entre las sesiones (sham: Δ−2±2 vs. EMI 40%: ∆−6±2ml, p=0,13). Ambas sesiones no tuvieron cambios en las variables PAS, PAD, PAM, DC y RPT, pero se observó un mayor incremento de la FC en la sesión EMI 40%. Solamente en la sesión sham hubo una reducción del VS.

RESUMO A literatura carece de um consenso sobre respostas hemodinâmicas durante o exercício muscular inspiratório (EMI). Este estudo buscou avaliar e comparar as respostas hemodinâmicas durante uma sessão de EMI com e sem carga resistiva. Para tanto, 15 homens sedentários foram submetidos a duas sessões randomizadas de EMI: 40% da pressão inspiratória máxima (EMI 40%) e sem carga resistiva (sham), realizadas por dois minutos em oito sessões e com intervalos de um minuto. A pressão arterial sistólica (PAS), pressão arterial diastólica (PAD), pressão arterial média (PAM), resistência periférica total (RPT), volume sistólico (VS), débito cardíaco (DC) e frequência cardíaca (FC) foram medidos por fotopletismografia infravermelha digital por cinco minutos basais e durante as sessões de EMI. Anova de uma via e o teste t de Student para dados pareados foram usados para analisar a resposta hemodinâmica e os valores delta entre as sessões. O tamanho do efeito foi avaliado pelo d de Cohen. Adotou-se nível de significância de 5%. As respostas de PAS (sham: ∆−1±2 vs. 40%: ∆−4±2mmHg, p=0,27), PAD (sham: ∆2±1 vs. 40%: ∆1±2mmHg, p=0,60) e PAM (sham: ∆2±1 vs. 40%: ∆0±2mmHg, p=0,28) foram semelhantes entre as sessões. Os aumentos da FC foram maiores na sessão de EMI 40% do que nas sessões sham (sham: ∆9±2 vs. 40%: ∆3±2bpm, p=0,001). O VS diminuiu exclusivamente durante a sessão sham mas a resposta foi semelhante entre as sessões (sham: ∆−2±2 vs. EMI 40%: ∆−6±2ml, p=0,13). Ambas as sessões não causaram alteração nas variáveis PAS, PAD, PAM, DC e RPT, mas notamos um aumento maior da FC na sessão EMI 40%. Apenas a sessão sham reduziu o VS.

Peripheral Vascular Resistance Impairment during Isometric Physical Exercise in Normotensive Offspring of Hypertensive Parents.

BACKGROUND:: A family history of hypertension is associated with vascular and autonomic abnormalities, as well as an impaired neurohemodynamic response to exercise. OBJECTIVE:: To test the hypothesis that normotensive individuals with a family history of hypertension present an impaired peripheral vascular resistance response to exercise. METHODS:: The study included 37 normotensive volunteers of both sexes who were sedentary, eutrophic, and nonsmokers, comprising 23 with (FH+; 24 ± 3 years) and 14 without (FH-; 27 ± 5 years) a family history of hypertension. Blood pressure, heart rate (DIXTAL®), forearm blood flow (Hokanson®), and peripheral vascular resistance were simultaneously measured for 3 minutes during rest and, subsequently, for 3 minutes during an isometric exercise at 30% of maximal voluntary contraction (Jamar®). RESULTS:: At rest, the FH+ and FH- groups present similar mean blood pressure (83 ± 7 versus 83 ± 5 mmHg, p = 0.96), heart rate (69 ± 8 bpm versus 66 ± 7 bpm, p = 0.18), forearm blood flow (3 ± 1 mL/min/100 mL versus 2.7 ± 1 mL/min/100 mL, p = 0.16), and peripheral vascular resistance (30 ± 9 units versus 34±9 units, p = 0.21), respectively. Both groups showed a significant and similar increase in mean blood pressure (∆ = 15 ± 7 mmHg versus 14 ± 7 mmHg, p = 0.86), heart rate (∆ = 12 ± 8 bpm versus 13 ± 7 bpm, p = 0.86), and forearm blood flow (∆ = 0.8 ± 1.2 mL/min/100 mL versus 1.4 ± 1.1 mL/min/100 mL, p = 0.25), respectively, during exercise. However, individuals in the FH+ group showed no reduction in peripheral vascular resistance during exercise, which was observed in the FH- group (∆ = -0.4 ± 8.6 units versus -7.2 ± 6.3 units, p = 0.03). CONCLUSION:: Normotensive individuals with a family history of hypertension present an impaired peripheral vascular resistance response to exercise. FUNDAMENTO:: O histórico familiar para hipertensão arterial está relacionado a anormalidades vasculares e autonômicas, bem como disfunções no comportamento neuro-hemodinâmico durante o exercício físico. OBJETIVO:: Testar a hipótese de que indivíduos normotensos com histórico familiar de hipertensão arterial apresentam resposta prejudicada da resistência vascular periférica durante o exercício físico. MÉTODOS:: Foram avaliados 37 normotensos de ambos os sexos, sedentários, eutróficos e não tabagistas, sendo 23 com histórico familiar positivo (HF+, 24 ± 3 anos) e 14 com histórico familiar negativo (HF-, 27 ± 5 anos) para hipertensão arterial. Foram identificados pressão arterial, frequência cardíaca (DIXTAL®), fluxo sanguíneo muscular do antebraço e resistência vascular periférica local (Hokanson®) por 3 minutos durante o repouso e, em seguida, 3 minutos durante exercício isométrico de preensão palmar a 30% da contração voluntária máxima (Jamar®). RESULTADOS:: Em repouso, os grupos HF+ e HF- apresentaram valores semelhantes de pressão arterial média (83 ± 7 mmHg versus 83 ± 5 mmHg, p = 0,96), frequência cardíaca (69 ± 8 bpm versus 66 ± 7 bpm, p = 0,18), fluxo sanguíneo muscular (3 ± 1 mL/min/199 mL versus 2,7 ± 1 mL/min/100 mL, p = 0,16) e resistência vascular periférica (30 ± 9 unidades versus 34 ± 9 unidades, p = 0,21), respectivamente. Durante o exercício, HF+ e HF- mostraram aumento significativo e semelhante da pressão arterial média (∆ = 15 ± 7 mmHg versus 14 ± 7 mmHg, p = 0,86), frequência cardíaca (∆ = 12 ± 8 bpm versus 13 ± 7 bpm, p = 0,86) e fluxo sanguíneo muscular (∆ = 0,8 ± 1,2 mL/min/100 mL versus 1,4 ± 1,1 mL/min/100 mL, p = 0,25), respectivamente. Entretanto, no grupo HF+ não houve redução significativa da resistência vascular periférica durante o exercício, fato que ocorreu no grupo HF- (∆ = -0,4 ± 8,6 unidades versus -7,2 ± 6,3 unidades, p = 0,03). CONCLUSÃO:: Indivíduos normotensos com histórico familiar de hipertensão arterial apresentam resposta prejudicada da resistência vascular periférica durante o exercício físico.

Different times of day do not change heart rate variability recovery after light exercise in sedentary subjects: 24 hours Holter monitoring.

Incidence of cardiovascular events follows a circadian rhythm with peak occurrence during morning. Disturbance of autonomic control caused by exercise had raised the question of the safety in morning exercise and its recovery. Furthermore, we sought to investigate whether light aerobic exercise performed at night would increase HR and decrease HRV during sleep. Therefore, the aim of this study was to test the hypothesis that morning exercise would delay HR and HRV recovery after light aerobic exercise, additionally, we tested the impact of late night light aerobic exercise on HR and HRV during sleep in sedentary subjects. Nine sedentary healthy men (age 24 ± 3 yr; height 180 ± 5 cm; weight 79 ± 8 kg; fat 12 ± 3%; mean±SD) performed 35 min of cycling exercise, at an intensity of first anaerobic threshold, at three times of day (7 a.m., 2 p.m. and 11 p.m.). R-R intervals were recorded during exercise and during short-time (60 min) and long-time recovery (24 hours) after cycling exercise. Exercise evoked increase in HR and decrease in HRV, and different times of day did not change the magnitude (p < 0.05 for time). Morning exercise did not delay exercise recovery, HR was similar to rest after 15 minutes recovery and HRV was similar to rest after 30 minutes recovery at morning, afternoon, and night. Low frequency power (LF) in normalized unites (n.u.) decreased during recovery when compared to exercise, but was still above resting values after 60 minutes of recovery. High frequency power (HF-n.u.) increased after exercise cessation (p < 0.05 for time) and was still below resting values after 60 minutes of recovery. The LF/HF ratio decreased after exercise cessation (p < 0.05 for time), but was still different to baseline levels after 60 minutes of recovery. In conclusion, morning exercise did not delay HR and HRV recovery after light aerobic cycling exercise in sedentary subjects. Additionally, exercise performed in the night did change autonomic control during the sleep. So, it seems that sedentary subjects can engage physical activity at any time of day without higher risk.