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1.
Auton Neurosci ; 221: 102582, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31493664

RESUMO

Heart rate recovery (HRR) has been widely used to evaluate the integrity of the autonomic nervous system with a slower HRR being associated with greater cardiovascular risk. Different HRR indices have been proposed. Some evaluate HR changes from the end of exercise to a specific recovery moment (e.g. 60s - HRR60s; 120s - HRR120s; 300s - HRR300s) and others calculate time-constant decays of HR for different recovery intervals (e.g. first 30s - T30; the entire period - HRRt). Several studies have examined the reproducibility of these commonly-used HRR indices, but reported discordant findings. Thus, this systematic review was designed to synthesize the reproducibility of HRR. We included studies that evaluated short-term (<1 year) reproducibility of HRR after dynamic exercise by employing typical measures of reliability (intraclass correlation coefficient, ICC) and agreement (coefficient of variation, CV). The electronic database PubMed/Medline was searched for relevant studies published up to July 2018. From the initial 120 records identified, 15 studies were retained for the qualitative synthesis of 24 experimental conditions. During most experimental conditions, high ICC and desirable CV were reported for HRR60s (62.5 and 76.2%, respectively), HRR120s (55.6 and 71.4%) and HRR300s (50.0 and 100.0%). While, it were reported during the minority of conditions for HRRt (37.5 and 42.9%) and in none condition for T30 (0.0 and 0.0%). In conclusion, HRR60s, HRR120s and HRR300s exhibited good reproducibility for evaluating HRR in predominantly healthy males within research and clinical settings. In contrast, caution should be taken when employing other HRR indices (T30, HRRt) due to their poorer reproducibility.

2.
Front Physiol ; 10: 762, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293439

RESUMO

Introduction: Previous studies observed diurnal variation in hemodynamic responses during recovery from whole-body exercise, with vasodilation appearing greater after evening versus morning sessions. It is unclear what mechanism(s) underlie this response. Since small muscle-mass exercise can isolate peripheral effects related to postexercise vasodilation, it may provide insight into possible mechanisms behind this diurnal variation. Methods: The study was conducted in ten healthy (5F, 5M) young individuals, following single-leg dynamic knee-extension exercise performed in the Morning (7:30-11:30 am) or the Evening (5-9 pm) on two different days, in random order. Arterial pressure (automated auscultation) and leg blood flow (femoral artery Doppler ultrasound) were measured pre-exercise and during 120 min postexercise. Net effect for each session was calculated as percent change in blood flow (or vascular conductance) between the Active Leg and the Inactive Leg. Results: Following Morning exercise, blood flow was 34.9 ± 8.9% higher in the Active Leg versus the Inactive Leg (p < 0.05) across recovery. Following Evening exercise, blood flow was 35.0 ± 8.8% higher in the Active Leg versus the Inactive Leg (p < 0.05). Likewise, vascular conductance was higher in the Active Leg versus the Inactive Leg (Morning: +35.1 ± 9.0%, p < 0.05; Evening: +33.2 ± 8.2%, p < 0.05). Morning and Evening blood flow (p = 0.66) and vascular conductance (p = 0.64) did not differ. Conclusion: These data suggest previous studies which identified diurnal variations in postexercise vasodilation responses are likely reflecting central rather than peripheral modulation of cardiovascular responses.

3.
Med Sci Sports Exerc ; 51(4): 653-662, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30489494

RESUMO

INTRODUCTION: The acute blood pressure (BP) decrease is greater after evening than morning exercise, suggesting that evening training (ET) may have a greater hypotensive effect. OBJECTIVE: This study aimed to compare the hypotensive effect of aerobic training performed in the morning versus evening in treated hypertensives. METHODS: Fifty treated hypertensive men were randomly allocated to three groups: morning training (MT), ET, and control (C). Training groups cycled for 45 min at moderate intensity (progressing from the heart rate of the anaerobic threshold to 10% below the heart rate of the respiratory compensation point), while C stretched for 30 min. Interventions were conducted 3 times per week for 10 wk. Clinic and ambulatory BP and hemodynamic and autonomic mechanisms were evaluated before and after the interventions. Clinic assessments were performed in the morning (7:00-9:00 AM) and evening (6:00-8:00 PM). Between-within ANOVA was used (P ≤ 0.05). RESULTS: Only ET decreased clinic systolic BP differently from C and MT (morning assessment -5 ± 6 mm Hg and evening assessment -8 ± 7 mm Hg, P < 0.05). Only ET reduced 24 h and asleep diastolic BP differently from C and MT (-3 ± 5 and -3 ± 4 mm Hg, respectively, P < 0.05). Systemic vascular resistance decreased from C only in ET (P = 0.03). Vasomotor sympathetic modulation decreased (P = 0.001) and baroreflex sensitivity (P < 0.02) increased from C in both training groups with greater changes in ET than MT. CONCLUSIONS: In treated hypertensive men, aerobic training performed in the evening decreased clinic and ambulatory BP due to reductions in systemic vascular resistance and vasomotor sympathetic modulation. Aerobic training conducted at both times of day increases baroreflex sensitivity, but with greater after ET.


Assuntos
Pressão Sanguínea/fisiologia , Exercício/fisiologia , Hipertensão/fisiopatologia , Condicionamento Físico Humano , Adulto , Anti-Hipertensivos/uso terapêutico , Barorreflexo/fisiologia , Humanos , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resistência Vascular/fisiologia , Sistema Vasomotor/fisiologia
4.
Ann Vasc Surg ; 57: 144-151, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30476599

RESUMO

BACKGROUND: The aim of this study is to identify, in patients with peripheral artery disease and intermittent claudication (IC), the reproducibility of heart rate (HR), blood pressure (BP), rate pressure product, heart rate variability (HRV), and forearm and calf blood flow (BF) and vasodilatory assessments. METHODS: Twenty-nine patients with IC underwent test and retest sessions, 8-12 days apart. During each session, HR, BP, HRV, BF, and vasodilatory responses were measured by electrocardiogram, auscultation, spectral analysis of HRV (low frequency, LFR-R; high frequency, HFR-R), and strain gauge plethysmography (baseline BF, post-occlusion BF, post-occlusion area under the curve). Reproducibility was determined by intra-class correlation coefficient (ICC), typical error, coefficient of variation (CV), and limits of agreement. RESULTS: The ICC for HR and BP was >0.8 with CV <9%. For most HRV measures, ICC was >0.9 while CV was <7%, except for LF/HF (ICC = 0.737, CV = 93.8%). The ICC for forearm and calf baseline BF assessments was >0.9 while CV was <19%; variable ICC and CV for vasodilatory responses were exhibited for calf (0.653-0.770, 35.2-37.7%) and forearm (0.169-0.265, 46.2-55.5%). CONCLUSIONS: In male patients with IC, systemic hemodynamics (HR and BP), cardiac autonomic modulation (LFR-R and HFR-R), and forearm and calf baseline BF assessments exhibited excellent reproducibility, whereas the level of reproducibility for vasodilatory responses were moderate to poor. Assessment reproducibility has highlighted appropriate clinical tools for the regular monitoring of disease/intervention progression in patients with IC.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Eletrocardiografia , Antebraço/irrigação sanguínea , Coração/inervação , Hemodinâmica , Claudicação Intermitente/diagnóstico , Perna (Membro)/irrigação sanguínea , Pletismografia , Idoso , Pressão Sanguínea , Frequência Cardíaca , Humanos , Claudicação Intermitente/fisiopatologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Vasodilatação
5.
J Strength Cond Res ; 33(2): 399-407, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28658080

RESUMO

Paulo, AC, Tricoli, V, Queiroz, ACC, Laurentino, G, and Forjaz, CLM. Blood pressure response during resistance training of different work-to-rest ratio. J Strength Cond Res 33(2): 399-407, 2019-Changes in the work-to-rest ratio (W:R) of resistance training protocols (RTPs) (i.e., decreasing work or increasing rest) reduce the marked elevation in blood pressure (BP) that occurs during RTP execution. However, whether changes in RTP structure without changing W:R can change BP responses to RTP is unknown. To investigate the effect of different structures of rest intervals and number of repetitions per set on BP response among RTP equated and nonequated for W:R, 20 normotensive participants (25 ± 4 years) performed 4 different RTP of the leg extension exercise with the same work but different W:R structures. Two protocols followed the recommendations for cardiovascular disorders: (a) HIGHW:R-3×15:44s-3×15:44s (set×reps:rest between sets), which has high W:R (45reps:88s) and (b) LOWW:R-3×15:88s-3×15:88s, which has low W:R (45reps:176s). The other 2 protocols were W:R-equated to LOWW:R (45reps:176s): (c) LOWW:R-9×5:22s and (d) LOWW:R-45×1:4s. Systolic BP (ΔSBP) and diastolic BP (ΔDBP) were assessed by finger photoplethysmography. There were significant main effects for ΔSBP after RTP (p ≤ 0.05): HIGHW:R-3×15:44s = LOWW:R-3×15:88s > LOWW:R-45×1:4s > LOWW:R-9×5:22s (+87 ± 5 and +84 ± 5 vs. +61 ± 4 vs. 57 ± 4 mm Hg). For ΔDBP, there was a significant interaction between RTP and moment (p ≤ 0.05). Thus, HIGHW:R-3×15:44 > LOWW:R-3×15:88s > LOWW:R-45×1:4s > LOWW:R-9×5:22s (+53 ± 5 vs. +49 ± 5 vs. +44 ± 4 vs. +38 ± 3 mm Hg). HIGHW:R-3×15:44s produced the highest increase in ΔDBP, and LOWW:R-9×5:22s produced the lowest increase in ΔSBP and ΔDBP. Our findings may help the development of RTP protocols that may mitigate pressure peaks without changing important exercise variables (i.e., volume or duration).


Assuntos
Pressão Sanguínea/fisiologia , Doenças Cardiovasculares/fisiopatologia , Treinamento de Resistência/métodos , Descanso/fisiologia , Adulto , Exercício/fisiologia , Feminino , Humanos , Masculino , Adulto Jovem
6.
J Am Soc Hypertens ; 12(12): e59-e64, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30425018

RESUMO

After an exercise session, a reduction of blood pressure (BP) is expected, a phenomenon called postexercise hypotension (PEH). PEH as a predictor of chronic training responses for BP has been broadly explored. It suggests that when PEH occurs after each exercise sessions, its benefits may summate over time, contributing to the chronic adaptation. Thus, PEH is an important clinical tool, acting as a "single brick" in the wall, and building the chronic effect of decreasing BP. However, there is large variation in the literature regarding methodology and results, creating barriers for understanding comparisons among PEH studies. Thus, the differences among subjects' and exercise protocols' characteristics observed in the studies investigating PEH must be considered when readers interpret the results. Furthermore, understanding of these factors of influence might be useful for avoiding misinterpretations in future comparisons and how the subjacent mechanisms contribute to the BP reduction after exercise.

7.
Blood Press Monit ; 23(6): 301-304, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30148716

RESUMO

This study analyzed the reproducibility of ambulatory blood pressure (BP) after high-intensity interval training (HIIT) sessions. Seventeen normotensive men (23.5±2.4 years) underwent two HIIT and two control sessions separated by 7-10 days. Ambulatory BP monitoring devices were used for 20 h. The intraclass correlation coefficient of BP in the awake and asleep periods ranged from 0.836 to 0.942 in the HIIT (P<0.05) and from 0.777 to 0.974 in the control sessions (P<0.05). The bias, limits of agreement, and pattern of distribution of awake BP were similar between HIIT and control sessions. However, for asleep BP, the bias and limits of agreement were not similar between HIIT and control sessions. In conclusion, in physically active adults, ambulatory BP after HIIT sessions presented good reproducibility only in the awake period.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea/fisiologia , Exercício/fisiologia , Adulto , Humanos , Masculino , Reprodutibilidade dos Testes
8.
PM R ; 10(11): 1145-1152, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29753113

RESUMO

BACKGROUND: Patients with Parkinson disease (PD) present cardiovascular autonomic dysfunction that impairs blood pressure control. However, cardiovascular responses during resistance exercise are unknown in these patients. OBJECTIVE: To investigate cardiovascular responses during resistance exercise performed with different muscle masses in patients with PD. DESIGN: Prospective, repeated-measures. SETTING: Exercise Hemodynamic Laboratory, School of Physical Education and Sport, University of São Paulo. PARTICIPANTS: Thirteen patients with PD (4 women, 62.7 ± 1.3 years, stages 2-3 of the modified Hoehn and Yahr scale; "on" state of medication) and 13 paired control patients without PD (7 women, 66.2 ± 2.0 years). INTERVENTIONS: Both groups performed, in a random order, bilateral and unilateral knee extension exercises (2 sets, 10-12 maximal repetition, 2-minute intervals). MAIN OUTCOME MEASUREMENTS: Systolic blood pressure (SBP) and heart rate (HR) were assessed before (pre) and during the exercises. RESULTS: Independent of set and exercise type, SBP and HR increases were significantly lower in PD than the control group (combined values: +45 ± 2 versus +73 ± 4 mm Hg and +18 ± 1 versus +31 ± 2 bpm, P = .003 and .007, respectively). Independently of group and set, the SBP increase was greater in the bilateral than the unilateral exercise (combined values: +63 ± 4 versus +54 ± 3 mm Hg, P = .002), whereas the HR increase was similar. In addition, independently of group and exercise type, the SBP increase was greater in the second than the first set (combined values: +56 ± 4 versus +61 ± 4 mm Hg, P = .04), whereas the HR increases were similar. CONCLUSIONS: Patients with PD present attenuated increases in SBP and HR during resistance exercise in comparison with healthy subjects. These results support that resistance exercise is safe and well tolerated for patients with PD from a cardiovascular point of view supporting its recommendation for this population. LEVEL OF EVIDENCE: II.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Doença de Parkinson/fisiopatologia , Treinamento de Resistência , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
9.
Obesity (Silver Spring) ; 26 Suppl 1: S5-S13, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29464921

RESUMO

OBJECTIVE: The purpose of this paper is to introduce the overarching study design of the South American Youth/Child Cardiovascular and Environmental (SAYCARE) study, which is an observational multicenter feasibility study held in seven South American cities: Buenos Aires (Argentina), Lima (Peru), Medellin (Colombia), Montevideo (Uruguay), Santiago (Chile), and São Paulo and Teresina (Brazil). Children and adolescents (3-17 years of age) were studied. METHODS: The data management systems, quality assurance monitoring activities, standardized operating procedure manuals, and training and study management are addressed in this paper. Various quality controls to ensure the collection of valid and reliable data are also discussed. RESULTS AND CONCLUSIONS: Data were obtained from 237 preschoolers and schoolchildren and 258 adolescents during the validation phase measurements. The results of the SAYCARE study are expected to provide higher accuracy in the assessment of cardiovascular disease risk factors, including eating behaviors, body composition, physical activity, sedentary behaviors, lipid profiles and cardiovascular health biomarkers, oral health, social conditions, environmental factors and home environment, and their determinants in children and adolescents from ages 3 to 17 in seven South American cities.


Assuntos
Doenças Cardiovasculares/epidemiologia , Meio Ambiente , Projetos de Pesquisa Epidemiológica , Metas , Adolescente , Sistema Cardiovascular/fisiopatologia , Criança , Pré-Escolar , Comportamento Alimentar/fisiologia , Feminino , Humanos , Estilo de Vida/etnologia , Masculino , Fatores de Risco , Fatores Socioeconômicos , América do Sul/epidemiologia
10.
Obesity (Silver Spring) ; 26 Suppl 1: S23-S30, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29464922

RESUMO

OBJECTIVE: The objective of this article is to test the reliability and validity of the new and innovative physical activity (PA) questionnaire. METHODS: Subsamples from the South American Youth/Child Cardiovascular and Environment Study (SAYCARE) study were included to examine its reliability (children: n = 161; adolescents: n = 177) and validity (children: n = 82; adolescents: n = 60). The questionnaire consists of three dimensions of PA (leisure, active commuting, and school) performed during the last week. To assess its validity, the subjects wore accelerometers for at least 3 days and 8 h/d (at least one weekend day). The reliability was analyzed by correlation coefficients. In addition, Bland-Altman analysis and a multilevel regression were applied to estimate the measurement bias, limits of agreement, and influence of contextual variables. RESULTS: In children, the questionnaire showed consistent reliability (ρ = 0.56) and moderate validity (ρ = 0.46), and the contextual variable variance explained 43.0% with -22.9 min/d bias. In adolescents, the reliability was higher (ρ = 0.76) and the validity was almost excellent (ρ = 0.88), with 66.7% of the variance explained by city level with 16.0 min/d PA bias. CONCLUSIONS: The SAYCARE PA questionnaire shows acceptable (in children) to strong (in adolescents) reliability and strong validity in the measurement of PA in the pediatric population from low- to middle-income countries.


Assuntos
Exercício/fisiologia , Inquéritos e Questionários , Adolescente , Criança , Pré-Escolar , Projetos de Pesquisa Epidemiológica , Feminino , Humanos , Atividades de Lazer , Masculino , Reprodutibilidade dos Testes , Instituições Acadêmicas/estatística & dados numéricos , América do Sul/epidemiologia , Inquéritos e Questionários/normas
11.
Gait Posture ; 61: 90-97, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29310015

RESUMO

Resistance training with instability (RTI) uses exercises with high motor complexity that impose high postural control and cognitive demands that may be important for improving postural instability and fear of falling in subjects with Parkinson's disease (PD). Here, we hypothesized that: 1) RTI will be more effective than resistance training (RT) in improving balance (Balance Evaluation Systems Test [BESTest] and overall stability index [Biodex Balance System®]) and fear of falling (Falls Efficacy Scale-International [FES-I] score) of subjects with Parkinson's disease (PD); and 2) changes in BESTest and FES-I after RTI will be associated with changes in cognitive function (Montreal Cognitive Assessment [MoCA] score - previously published) induced by RTI. Thirty-nine subjects with moderate PD were randomly assigned to a nonexercising control, RT, and RTI groups. While RT and RTI groups performed progressive RT twice a week for 12 weeks, the RTI group added progressive unstable devices to increase motor complexity of the resistance exercises. There were significant group × time interactions for BESTest, overall stability index, and FES-I scores (P < 0.05). Only RTI improved BESTest, overall stability index and FES-I scores, and RTI was more effective than RT in improving biomechanical constraints and stability in gait (BESTest sections) at post-training (P < 0.05). There were strong correlations between relative changes in BESTest and MoCA (r = 0.72, P = 0.005), and FES-I and MoCA (r = -0.75, P = 0.003) after RTI. Due to the increased motor complexity in RTI, RTI is recommended for improving balance and fear of falling, which are associated with improvement in cognitive function of PD.


Assuntos
Acidentes por Quedas/prevenção & controle , Cognição/fisiologia , Terapia por Exercício/métodos , Medo/psicologia , Marcha/fisiologia , Doença de Parkinson/reabilitação , Equilíbrio Postural/fisiologia , Idoso , Idoso de 80 Anos ou mais , Exercício/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia
12.
Clin Physiol Funct Imaging ; 38(1): 69-75, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27491344

RESUMO

The aim of this study was to compare the effects of a single session of walking and combined exercise on oxidative stress and vascular function in peripheral arterial disease patients. Thirteen patients with peripheral arterial disease underwent two experimental sessions in random order: walking (ten sets of 2-min walking at the speed corresponding to the onset of claudication pain with 2-min interval between sets) and combined exercise (1 × 10 reps in eight resistance exercises plus five-two-minute sets of walking). Before and after the exercise, vascular function (blood flow, leg vascular resistance and blood-flow postreactive hyperaemia) and oxidative stress (malondialdehyde and plasma nitrite levels) were obtained. Blood flow increased similarly after both sessions, whilst leg vascular resistance decreased similarly after both sessions. Plasma nitrite increased only after the combined exercise. Malondialdehyde decreased after both sessions, and the decrease was greater after combined exercise. As a conclusion, a single session of combined exercise improves blood flow and leg vascular resistance similarly to walking session; however, combined exercise promoted better effects on oxidative stress.


Assuntos
Hemodinâmica , Claudicação Intermitente/terapia , Extremidade Inferior/irrigação sanguínea , Estresse Oxidativo , Doença Arterial Periférica/terapia , Treinamento de Resistência/métodos , Velocidade de Caminhada , Idoso , Índice Tornozelo-Braço , Biomarcadores/sangue , Pressão Sanguínea , Feminino , Humanos , Hiperemia/fisiopatologia , Claudicação Intermitente/sangue , Claudicação Intermitente/diagnóstico , Claudicação Intermitente/fisiopatologia , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Nitritos/sangue , Doença Arterial Periférica/sangue , Doença Arterial Periférica/diagnóstico , Doença Arterial Periférica/fisiopatologia , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Resistência Vascular
13.
J Appl Physiol (1985) ; 123(6): 1555-1562, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28860171

RESUMO

This study assessed the additive effects of passive heating and exercise on cardiac baroreflex sensitivity (cBRS) and heart rate variability (HRV). Twelve healthy young men (25 ± 1 yr, 23.8 ± 0.5 kg/m2) randomly underwent two experimental sessions: heat stress (HS; whole body heat stress using a tube-lined suit to increase core temperature by ~1°C) and normothermia (NT). Each session was composed of a preintervention rest (REST1); HS or NT interventions; postintervention rest (REST2); and 14 min of cycling exercise [7 min at 40%HRreserve (EX1) and 7 min at 60%HRreserve (EX2)]. Heart rate and finger blood pressure were continuously recorded. cBRS was assessed using the sequence (cBRSSEQ) and transfer function (cBRSTF) methods. HRV was assessed using the indexes standard deviation of RR intervals (SDNN) and root mean square of successive RR intervals (RMSSD). cBRS and HRV were not different between sessions during EX1 and EX2 (i.e., matched heart rate conditions: EX1 = 116 ± 3 vs. 114 ± 3 and EX2 = 143 ± 4 vs. 142 ± 3 beats/min but different workloads: EX1 = 50 ± 9 vs. 114 ± 8 and EX2 = 106 ± 10 vs. 165 ± 8 W; for HS and NT, respectively; P < 0.01). However, when comparing EX1 of NT with EX2 of HS (i.e., matched workload conditions but with different heart rates), cBRS and HRV were significantly reduced in HS (cBRSSEQ = 1.6 ± 0.3 vs. 0.6 ± 0.1 ms/mmHg, P < 0.01; SDNN = 2.3 ± 0.1 vs. 1.3 ± 0.2 ms, P < 0.01). In conclusion, in conditions matched by HR, the addition of heat stress to exercise does not affect cBRS and HRV. Alternatively, in workload-matched conditions, the addition of heat to exercise results in reduced cBRS and HRV compared with exercise in normothermia. NEW & NOTEWORTHY The present study assessed cardiac baroreflex sensitivity during the combination of heat and exercise stresses. This is the first study to show that prior whole body passive heating reduces cardiac baroreflex sensitivity and autonomic modulation of heart rate during exercise. These findings contribute to the better understanding of the role of thermoregulation on cardiovascular regulation during exercise.


Assuntos
Barorreflexo , Exercício , Frequência Cardíaca , Temperatura Alta , Adulto , Sistema Nervoso Autônomo , Pressão Sanguínea , Regulação da Temperatura Corporal , Humanos , Masculino , Estresse Fisiológico , Adulto Jovem
14.
Blood Press Monit ; 22(3): 115-121, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28195842

RESUMO

OBJECTIVE: Patients with intermittent claudication (IC) often have high blood pressure (BP), which increases their cardiovascular risk. However, whether walking capacity is associated with BP levels in patients with IC remains unknown. Therefore, this study was designed to investigate whether the total walking distance is associated with ambulatory BP in patients with IC. PARTICIPANTS AND METHODS: This was a cross-sectional study of 75 patients with IC (58 men; 17 women). A maximal treadmill test (Gardner protocol) was performed to assess total walking distance in these patients. Furthermore, ambulatory BP, heart rate, rate-pressure product, and BP load were obtained over a 24-h period. One-way analysis of variance and multiple linear regression were carried out. RESULTS: Walking capacity was correlated negatively with the following: (i) asleep systolic BP, diastolic BP, mean BP and heart rate; (ii) 24-h, awake and asleep RPP; and (iii) awake and asleep systolic BP load (all P<0.05). These associations occurred irrespective of confounders such as age, sex, BMI, smoking status, and number of antihypertensive medications. CONCLUSION: A better walking capacity is associated with lower ambulatory BP parameters in patients with IC.


Assuntos
Monitorização Ambulatorial da Pressão Arterial , Pressão Sanguínea , Claudicação Intermitente/fisiopatologia , Caminhada , Idoso , Monitorização Ambulatorial da Pressão Arterial/métodos , Estudos Transversais , Teste de Esforço , Feminino , Frequência Cardíaca , Humanos , Claudicação Intermitente/diagnóstico , Masculino , Pessoa de Meia-Idade
15.
J Strength Cond Res ; 31(8): 2263-2269, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27787467

RESUMO

Dantas, TCB, Farias Junior, LF, Frazão, DT, Silva, PHM, Sousa Junior, AE, Costa, IBB, Ritti-Dias, RM, Forjaz, CLM, Duhamel, TA, and Costa, EC. A single session of low-volume high-intensity interval exercise reduces ambulatory blood pressure in normotensive men. J Strength Cond Res 31(8): 2263-2269, 2017-The magnitude and duration of postexercise hypotension (PEH) may provide valuable information on the efficacy of an exercise approach to blood pressure (BP) control. We investigated the acute effect of a time-efficient high-intensity interval exercise (HIIE) on ambulatory BP. Twenty-one normotensive men (23.6 ± 3.6 years) completed 2 experimental sessions in a randomized order: (a) control (no exercise) and (b) low-volume HIIE: 10 × 1 minute at 100% of maximal treadmill velocity interspersed with 1 minute of recovery. After each experimental session, an ambulatory BP monitoring was initiated. Paired sample t-test was used to compare BP averages for awake, asleep, and 20-hour periods between the control and the low-volume HIIE sessions. A 2-way repeated measures analysis of variance was used to analyze hourly BP after both experimental sessions. Blood pressure averages during the awake (systolic: 118 ± 6 vs. 122 ± 6 mm Hg; diastolic: 65 ± 7 vs. 67 ± 7 mm Hg) and 20-hour (systolic: 115 ± 7 vs. 118 ± 6 mm Hg; diastolic: 62 ± 7 vs. 64 ± 7 mm Hg) periods were lower after the low-volume HIIE compared with the control (p ≤ 0.05). Systolic and diastolic PEH presented medium (Cohen's d = 0.50-0.67) and small (Cohen's d = 0.29) effect sizes, respectively. Systolic PEH occurred in a greater magnitude during the first 5 hours (3-5 mm Hg). No changes were found in asleep BP (p > 0.05). In conclusion, a single session of low-volume HIIE reduced ambulatory BP in normotensive men. The PEH occurred mainly in systolic BP during the first 5 hours postexercise.


Assuntos
Pressão Sanguínea/fisiologia , Exercício/fisiologia , Hipotensão Pós-Exercício/patologia , Adulto , Monitorização Ambulatorial da Pressão Arterial , Estudos Cross-Over , Humanos , Hipertensão/fisiopatologia , Masculino , Hipotensão Pós-Exercício/fisiopatologia , Adulto Jovem
16.
Am J Nephrol ; 43(3): 206-12, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27096580

RESUMO

BACKGROUND: This study aimed at evaluating the after effects of a single bout of aerobic exercise on muscle sympathetic nerve activity (MSNA), peripheral vascular resistance and blood pressure (BP) in stages 2-3 chronic kidney disease (CKD) patients. We hypothesized that CKD patients present a greater decline in these variables after the exercise than healthy individuals. METHODS: Nine patients with stages 2-3 CKD (50 ± 8 years) and 12 healthy volunteers (50 ± 5 years) underwent 2 sessions, conducted in a random order: exercise (45 min, cycle ergometer, 50% of peak oxygen uptake) and rest (seated, 45 min). Sixty minutes after either intervention, MSNA (by microneurography), BP (by oscillometry), and forearm vascular resistance (FVR) were measured. A 2-way analysis of variance with group (between) and session (within) as main factors was employed, accepting p < 0.05 as significant. RESULTS: Diastolic BP and MSNA were higher in the CKD than the control group in both sessions. Responses after exercise were similar in both groups. Systolic BP, diastolic BP, MSNA and FVR were significantly lower after the exercise than after the rest session in both the CKD and the control groups (162 ± 15 vs. 152 ± 23 and 155 ± 11 vs. 145 ± 16 mm Hg, 91 ± 11 vs. 85 ± 14 and 77 ± 5 vs. 71 ± 10 mm Hg, 38 ± 4 vs. 31 ± 4 and 34 ± 2 vs. 27 ± 4 burst/min, 59 ± 29 vs. 41 ± 29 and 45 ± 20 vs. 31 ± 8 U, respectively, all p < 0.05). CONCLUSION: These results showed that aerobic exercise may produce hemodynamic and neural responses that can be beneficial to these patients in spite of CKD.


Assuntos
Pressão Sanguínea , Exercício/fisiologia , Insuficiência Renal Crônica/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Resistência Vascular/fisiologia , Adulto , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
17.
Med Sci Sports Exerc ; 48(9): 1678-87, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27054681

RESUMO

PURPOSE: This randomized controlled trial compared the effects of resistance training (RT) and RT with instability (RTI) on the timed up and go test (TUG), on-medication Unified Parkinson's Disease Rating Scale part III motor subscale score (UPDRS-III), Montreal Cognitive Assessment (MoCA) score, Parkinson's Disease Questionnaire (PDQ-39) score, and muscle strength in the leg press exercise (one-repetition maximum) of patients with Parkinson's disease (PD). METHODS: Thirty-nine patients with moderate to severe PD were randomly assigned to a nonexercising control group (C), RT group, and RTI group. The RT and RTI groups performed progressive RT twice a week for 12 wk. However, only the RTI group used high motor complexity exercises (i.e., progressive RT with unstable devices), for example, half squat exercise on the BOSU® device. The primary outcome was mobility (TUG). The secondary outcomes were on-medication motor signs (UPDRS-III), cognitive impairment (MoCA), quality of life (PDQ-39), and muscle strength (one-repetition maximum). RESULTS: There were no differences between RTI and RT groups for any of the outcomes at posttraining (P > 0.05). However, there were differences between RTI and C groups in the TUG, MoCA, and muscle strength values at posttraining (P < 0.05). Only the RTI group improved the TUG (-1.9 s), UPDRS-III score (-4.5 score), MoCA score (6.0 score), and PDQ-39 score (-5.2 score) from pre- to posttraining (P < 0.001). Muscle strength improved for both training groups (P < 0.001). No adverse events were reported during the trial. CONCLUSIONS: Both training protocols improved muscle strength, but only RTI improved the mobility, motor signs, cognitive impairment, and quality of life, likely because of the usage of high motor complexity exercises. Thus, RTI may be recommended as an innovative adjunct therapeutic intervention for patients with PD.


Assuntos
Terapia por Exercício/métodos , Doença de Parkinson/terapia , Treinamento de Resistência , Idoso , Cognição , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Limitação da Mobilidade , Força Muscular , Estudos Prospectivos , Qualidade de Vida
18.
PLoS One ; 10(7): e0132458, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26186444

RESUMO

Post-exercise hypotension (PEH), calculated by the difference between post and pre-exercise values, it is greater after exercise performed in the evening than the morning. However, the hypotensive effect of morning exercise may be masked by the morning circadian increase in blood pressure. This study investigated PEH and its hemodynamic and autonomic mechanisms after sessions of aerobic exercise performed in the morning and evening, controlling for responses observed after control sessions performed at the same times of day. Sixteen pre-hypertensive men underwent four sessions (random order): two conducted in the morning (7:30 am) and two in the evening (5 pm). At each time of day, subjects underwent an exercise (cycling, 45 min, 50%VO2peak) and a control (sitting rest) session. Measurements were taken pre- and post-interventions in all the sessions. The net effects of exercise were calculated for each time of day by [(post-pre exercise)-(post-pre control)] and were compared by paired t-test (P<0.05). Exercise hypotensive net effects (e.g., decreasing systolic, diastolic and mean blood pressure) occurred at both times of day, but systolic blood pressure reductions were greater after morning exercise (-7±3 vs. -3±4 mmHg, P<0.05). Exercise decreased cardiac output only in the morning (-460±771 ml/min, P<0.05), while it decreased stroke volume similarly at both times of day and increased heart rate less in the morning than in the evening (+7±5 vs. +10±5 bpm, P<0.05). Only evening exercise increased sympathovagal balance (+1.5±1.6, P<0.05) and calf blood flow responses to reactive hyperemia (+120±179 vs. -70±188 U, P<0.05). In conclusion, PEH occurs after exercise conducted at both times of day, but the systolic hypotensive effect is greater after morning exercise when circadian variations are considered. This greater effect is accompanied by a reduction of cardiac output due to a smaller increase in heart rate and cardiac sympathovagal balance.


Assuntos
Exercício/fisiologia , Hipotensão Pós-Exercício/fisiopatologia , Adulto , Sistema Nervoso Autônomo/fisiopatologia , Estudos Cross-Over , Hemodinâmica , Humanos , Masculino , Fluxo Sanguíneo Regional , Fatores de Tempo
19.
Am J Physiol Heart Circ Physiol ; 309(5): H897-905, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26116711

RESUMO

Increased oxidative stress and inflammation contribute to impaired walking capacity and endothelial dysfunction in patients with intermittent claudication (IC). The goal of the study was to determine the effects of oral treatment with the antioxidant N-acetylcysteine (NAC) on walking capacity, leg postocclusive reactive hyperemia, circulating levels of inflammatory mediators, and whole blood expression of angiogenic mediators in patients with IC. Following a double-blinded randomized crossover design, 10 patients with IC received NAC (1,800 mg/day for 4 days plus 2,700 mg before the experimental session) and placebo (PLA) before undergoing a graded treadmill exercise test. Leg postocclusive reactive hyperemia was assessed before and after the test. Blood samples were taken before and after NAC or PLA ingestions and 5 and 30 min after the exercise test for the analysis of circulating inflammatory and angiogenic markers. Although NAC increased the plasma ratio of reduced to oxidized glutathione, there were no differences between experimental sessions for walking tolerance and postocclusive reactive hyperemia. Plasma concentrations of soluble vascular cell adhesion protein-1, monocyte chemotactic protein-1, and endothelin-1 increased similarly following maximal exercise after PLA and NAC (P < 0.001). Whole blood expression of pro-angiogenic microRNA-126 increased after maximal exercise in the PLA session, but treatment with NAC prevented this response. Similarly, exercise-induced changes in whole blood expression of VEGF, endothelial nitric oxide synthase and phosphatidylinositol 3-kinase R2 were blunted after NAC. In conclusion, oral NAC does not increase walking tolerance or leg blood flow in patients with IC. In addition, oral NAC prevents maximal exercise-induced increase in the expression of circulating microRNA-126 and other angiogenic mediators in patients with IC.


Assuntos
Acetilcisteína/uso terapêutico , Antioxidantes/uso terapêutico , Hiperemia/tratamento farmacológico , Claudicação Intermitente/tratamento farmacológico , Caminhada , Acetilcisteína/administração & dosagem , Administração Oral , Idoso , Antioxidantes/administração & dosagem , Quimiocina CCL2/sangue , Endotelinas/sangue , Humanos , Hiperemia/sangue , Inflamação/sangue , Inflamação/tratamento farmacológico , Claudicação Intermitente/sangue , Perna (Membro)/irrigação sanguínea , Masculino , MicroRNAs/sangue , Pessoa de Meia-Idade , Óxido Nítrico Sintase Tipo III/sangue , Fosfatidilinositol 3-Quinases/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , Fator A de Crescimento do Endotélio Vascular/sangue
20.
Appl Physiol Nutr Metab ; 40(1): 59-64, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25485893

RESUMO

No study has shown the effects of acute resistance exercise on vasodilatory capacity of patients with peripheral artery disease. The aim of this study was to analyse the effects of a single session of resistance exercise on blood flow, reactive hyperemia, plasma nitrite, and plasma malondialdehyde in patients with peripheral artery disease. Fourteen peripheral artery disease patients underwent, in a random order, 2 experimental sessions: control (rest for 30 min) and resistance exercise (8 exercises, 2 sets of 10 repetitions at an intensity of 5-7 in the OMNI Resistance Exercise Scale). Blood flow, reactive hyperemia, plasma nitrite, and malondialdehyde were measured before and 40 min after the interventions in both sessions. Data were compared between sessions by analysis of covariance, using pre-intervention values as covariates. The increases in blood flow, reactive hyperemia, and log plasma nitrite were greater (p ≤ 0.05) after resistance exercise than the control session (3.2 ± 0.1 vs. 2.7 ± 0.1 mL · 100 mL(-1) tissue · min(-1), 8.0 ± 0.1 vs. 5.7 ± 0.1 AU, and 1.36 ± 0.01 vs. 1.26 ± 0.01 µmol ∙ L(-1), respectively). On the other hand, malondialdehyde was similar between sessions (p > 0.05). In peripheral arterial disease patients, a single session of resistance exercise increases blood flow and reactive hyperemia, which seems to be mediated, in part, by increases in nitric oxide release.


Assuntos
Claudicação Intermitente/terapia , Perna (Membro)/irrigação sanguínea , Fluxo Sanguíneo Regional , Treinamento de Resistência , Vasodilatação , Idoso , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Hiperemia/etiologia , Hipertensão/etiologia , Claudicação Intermitente/etiologia , Claudicação Intermitente/metabolismo , Claudicação Intermitente/fisiopatologia , Peroxidação de Lipídeos , Masculino , Malondialdeído/sangue , Microvasos/metabolismo , Microvasos/fisiopatologia , Pessoa de Meia-Idade , Óxido Nítrico/metabolismo , Nitritos/sangue , Nitritos/metabolismo , Doença Arterial Periférica/fisiopatologia , Treinamento de Resistência/efeitos adversos
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