RAAS polymorphisms alter the acute blood pressure response to aerobic exercise among men with hypertension

Effect of supervised exercise training on cardiovascular function in patients with intermittent claudication: a systematic review and meta-analysis of randomized controlled trials

This study aimed to determine the effect of supervised exercise training (SET) on cardiovascular function in patients with intermittent claudication (IC). A systematic search in MEDLINE, Embase, and Cochrane Central Register of Controlled Trials databases was conducted. Primary outcomes were systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), rate pressure product (RPP), cardiac output (CO), peak oxygen consumption (VO2peak), and heart rate variability (HRV). Secondary outcomes were maximum walking distance (MWD) and pain-free walking distance (PFWD). Outcomes were reported as weighted mean difference (WMD) between the SET group and the control group and synthesized by using the random-effects model. Seventeen RCTs with a total of 936 patients were included in this review. SET resulted in significant improvements of SBP (WMD =  - 7.40, 95% CI - 10.69 ~  - 4.11, p < 0.001, I2 = 15.2%), DBP (WMD =  - 1.92, 95% CI - 3.82 ~  - 0.02, p = 0.048, I2 = 0.0%), HR (WMD =  - 3.38, 95% CI - 6.30 ~  - 0.46, p = 0.023, I2 = 0.0%), RPP (WMD =  - 1072.82, 95% CI - 1977.05 ~  - 168.59, p = 0.020, I2 = 42.7%), and VO2peak with plantar flexion ergometer exercise (WMD = 5.57, 95% CI 1.66 ~ 9.49, p = 0.005, I2 = 62.4%), whereas CO and HRV remained statistically unaltered. SET also improved MWD (WMD = 139.04, 95% CI 48.64 ~ 229.44, p = 0.003, I2 = 79.3%) and PFWD (WMD = 40.02, 95% CI 23.85 ~ 56.18, p < 0.001, I2 = 0.0%). In conclusion, SET is effective in improving cardiovascular function in patients with IC, which was confirmed on outcomes of cardiovascular function associated with exercise ability. The findings hold out that the standard therapy of SET can improve not only walking distance but also cardiovascular function in patients with IC.

Effects of Acute Aquatic High-Intensity Intermittent Exercise on Blood Pressure and Arterial Stiffness in Postmenopausal Women with Different ACE Genotypes

The present study investigated the effects of acute aquatic high-intensity intermittent jumping (HIIJ) on blood pressure (BP) and arterial stiffness in postmenopausal women with different angiotensin-converting enzyme genotypes (ACE). We recruited 12 postmenopausal women carrying the ACE deletion/deletion (DD) genotype and 61 carrying the insertion/insertion or insertion/deletion (II/ID) genotype. The participants performed 12 trials of 30 s, 75% heart rate reserve (HRR) jumping, and 60 s, 50% HRR recovery, and 3 trials of 40 s upper limb resistance exercises were performed as fast as possible. The heart rate (HR) and BP were measured before exercise, immediately, 10 min, and 45 min after exercise. The brachial-ankle pulse wave velocity (baPWV) was measured before and after exercise. The systolic blood pressure (SBP) of the DD genotype increased more significantly than those with the II/ID genotype post-exercise (30.8 ± 4.48 vs. 20.4 ± 2.00 mmHg, p = 0.038). The left and right sides of baPWV increased significantly after exercise (1444.8 ± 29.54 vs. 1473.4 ± 32.36 cm/s, p = 0.020; 1442.1 ± 30.34 vs. 1472.0 ± 33.09, p = 0.011), and there was no significant difference between the two groups. The HIIJ increased baPWV. The postmenopausal women with the DD genotype have a higher SBP increased post-exercise than those with II/ID genotype. These findings suggest that the aquatic exercise program has better effects in decreasing blood pressure in postmenopausal women with the II/ID genotype. Those with the DD genotype should pay attention to the risk of increasing blood pressure after aquatic HIIJ exercise.

Physical Activity and the Acute Hemodynamic Response to ACE Inhibition in Hypertension

Introduction. Physical activity (PA) can reduce blood pressure (BP) in hypertensives through possibly interacting with the renin-angiotensin-aldosterone system (RAAS). We conducted a nested-cohort analysis to determine if self-reported PA was associated with BP responsiveness to acute angiotensin converting enzyme inhibition (ACEi). Methods. Data were extracted from the HyperPATH dataset, a cohort designed to identify mechanisms of cardiometabolic risk. Hypertensives that completed a self-assessed PA questionnaire, hormonal assessments (aldosterone [ALDO]), and BP to a single dose of an ACEi (captopril, 25 mg) were included. All participants (n = 144) were studied on a controlled diet for 7 days. PA was recorded as no PA, or little, moderate, or high amounts of exercise. Analyses were adjusted for age, sex, race, and body mass index. Results. Individuals who reported high amounts of PA displayed a greater BP lowering effect from ACEi compared to those who reported moderate (−14.8 ± 8.1 vs −8.4 ± 9.9 mm Hg, P < .01) or no additional PA (−14.8 ± 8.1 vs −2.6 ± 9.9 mm Hg, P < .001). Exploratory analyses indicated high amounts of PA were associated with a reduced heart rate (54 ± 8 vs 66 ± 10 bpm, P < .001) and blunted ALDO (β = 0.44, 95% confidence interval = 0.19-0.70). Conclusions. Higher self-reported PA was associated with an augmented BP lowering effect to acute ACEi in hypertensive patients.

The relation between submaximal aerobic exercise improving vascular elasticity through loss of visceral fat and antihypertensive

Purpose: We sought to observe the effect of submaximal aerobic exercise on abdominal obesity in hypertension patients and to clarify a correlation between blood pressure improvement and visceral fat, along with arterial elasticity. Materials and Methods: According to the treatment plan, the patients were divided into two groups: the combined treatment group and the single drug group. During the training period, the subjects in the combined treatment group performed a 60 min treadmill exercise at 65% of Pmax. PWV was measured using blood pressure pulse-wave detectors before and after treatment. We assessed carotid stiffness and visceral fat area by B‑mode ultrasonography. Results: The 24-h SBP and DBP changed significantly in the two groups in the pre- and post-treatment comparison. Significant statistical differences among SBP and DBP in the two groups of combination therapy and drug therapy after 12 months were demonstrated. Visceral fat area was significantly reduced in the combination therapy group compared to the drug therapy group at the last assessment. Compared with the drug group, arterial compliance in the combination therapy group was higher after treatment. Blood pressure showed significant positive correlation with visceral fat area, PWV, β‑stiffness, Ep, and PWVβ in the combination therapy group. Conclusion: The combination of drug therapy and is more effective than just pursuing single drug treatment of hypertension in patients with abdominal obesity. Submaximal aerobic exercise contributes to anti-hypertension. The main mechanism of anti-hypertension in combination with drug therapy and submaximal aerobic exercise is the improvement of vascular elasticity and decreased central body-fat distribution.

Sinapine Thiocyanate Ameliorates Vascular Endothelial Dysfunction in Hypertension by Inhibiting Activation of the NLRP3 Inflammasome

The increase of blood pressure is accompanied by the changes in the morphology and function of vascular endothelial cells. Vascular endothelial injury and hypertension actually interact as both cause and effect. A large number of studies have proved that inflammation plays a significant role in the occurrence and development of hypertension, but the potential mechanism between inflammation and hypertensive endothelial injury is still ambiguous. The purpose of this study was to explore the association between the activation of NLRP3 inflammasome and hypertensive endothelial damage, and to demonstrate the protective effect of sinapine thiocyanate (ST) on endothelia in hypertension. The expression of NLRP3 gene was silenced by tail vein injection of adeno-associated virus (AAVs) in spontaneously hypertensive rats (SHRs), indicating that activation of NLRP3 inflammasome accelerated hypertensive endothelial injury. ST not only protected vascular endothelial function in SHRs by inhibiting the activation of NLRP3 inflammasome and the expression of related inflammatory mediators, but also improved AngII-induced huvec injury. In summary, our results show that alleviative NLRP3 inflammasome activation attenuates hypertensive endothelial damage and ST ameliorates vascular endothelial dysfunction in hypertension via inhibiting activation of the NLRP3 inflammasome.

Association Between Hospital Anxiety Depression Scale and Autonomic Recovery Following Exercise

The hospital anxiety depression scale (HADS) is a benchmark used to investigate possible and probable cases of psychosomatic illness. Its affiliation with autonomic recovery after exercise is unclear and, as a technique applied to evaluate cardiovascular risk. We assessed a possible link between HADS and autonomic recovery after exercise. We studied healthy subjects split into two groups: Low HADS (n = 20) and High HADS (n = 21). Subjects consented to moderate aerobic exercise on a treadmill at 60% to 65% of the maximum heart rate (HR) for 30 min. We studied HR variability (HRV) before and during 30 min after exercise. Subjects with higher HADS values presented delayed recovery of HR and root-mean square of differences between adjacent normal RR intervals (RMSSD) after submaximal exercise. RMSSD during recovery from exercise had a significant association with HADS. In summary, subjects with higher HADS presented slower vagal recovery following exercise.

A Systematically Assembled Signature of Genes to be Deep-Sequenced for Their Associations with the Blood Pressure Response to Exercise

: Background: Exercise is one of the best nonpharmacologic therapies to treat hypertension. The blood pressure (BP) response to exercise is heritable. Yet, the genetic basis for the antihypertensive effects of exercise remains elusive. Methods: To assemble a prioritized gene signature, we performed a systematic review with a series of Boolean searches in PubMed (including Medline) from earliest coverage. The inclusion criteria were human genes in major BP regulatory pathways reported to be associated with: (1) the BP response to exercise; (2) hypertension in genome-wide association studies (GWAS); (3) the BP response to pharmacotherapy; (4a) physical activity and/or obesity in GWAS; and (4b) BP, physical activity, and/or obesity in non-GWAS. Included GWAS reports disclosed the statistically significant thresholds used for multiple testing. Results: The search yielded 1422 reports. Of these, 57 trials qualified from which we extracted 11 genes under criteria 1, 18 genes under criteria 2, 28 genes under criteria 3, 27 genes under criteria 4a, and 29 genes under criteria 4b. We also included 41 genes identified from our previous work. Conclusions: Deep-sequencing the exons of this systematically assembled signature of genes represents a cost and time efficient approach to investigate the genomic basis for the antihypertensive effects of exercise.

FURIN variant associations with postexercise hypotension are intensity and race dependent

FURIN is a proprotein convertase subtilisin/kexin enzyme important in pro-renin receptor processing, and FURIN (furin, paired basic amino acid cleaving enzyme) variants are involved in multiple aspects of blood pressure (BP) regulation. Therefore, we examined associations among FURIN variants and the immediate blood pressure (BP) response to bouts of aerobic exercise, termed postexercise hypotension (PEH). Obese (30.9 ± 3.6 kg  m-2 ) Black- (n = 14) and White- (n = 9) adults 42.0 ± 9.8 year with hypertension (139.8 ± 10.4/84.6 ± 6.2 mmHg) performed three random experiments: bouts of vigorous (VIGOROUS) and moderate (MODERATE) intensity cycling and control. Subjects were then attached to an ambulatory BP monitor for 19 h. We performed deep-targeted exon sequencing with the Illumina TruSeq Custom Amplicon kit. FURIN genotypes were coded as the number of minor alleles (#MA) and selected for additional statistical analysis based upon Bonferonni or Benjamini-Yekutieli multiple testing corrected P-values under time-adjusted linear models for 19 hourly BP measurements. After VIGOROUS over 19 h, as FURIN #MA increased in rs12917264 (P = 2.4E-04) and rs75493298 (P = 6.4E-04), systolic BP (SBP) decreased 30.4-33.7 mmHg; and in rs12917264 (P = 1.6E-03) and rs75493298 (P = 9.7E-05), diastolic BP (DBP) decreased 17.6-20.3 mmHg among Blacks only. In addition, after MODERATE over 19 h in FURIN rs74037507 (P = 8.0E-04), as #MA increased, SBP increased 20.8 mmHg among Blacks only. Whereas, after MODERATE over the awake hours in FURIN rs1573644 (P = 6.2E-04), as #MA increased, DBP decreased 12.5 mmHg among Whites only. FURIN appears to exhibit intensity and race-dependent associations with PEH that merit further exploration among a larger, ethnically diverse sample of adults with hypertension.

Postexercise Hypotension as a Predictor for Long-Term Training-Induced Blood Pressure Reduction: A Large-Scale Randomized Controlled Trial

OBJECTIVE

To investigate the correlation between acute exercise effects and chronic training effects on blood pressure (BP).

DESIGN

Randomized, controlled training study focusing on the optimization of preventive effects of physical training.

SETTING

The study was performed in a university department.

PARTICIPANTS

One hundred twenty-seven healthy, untrained subjects.

INTERVENTION

Subjects were divided into 4 groups: interval endurance training (IET) (n = 26, 4 × 4 min at 95% maximal heart rate), continuous endurance training (CET) (n = 23, 45 minutes at 60% heart rate reserve), strength endurance training (SET) (n = 40, 8 machine-based exercises, each 2 x 15 repetitions at the 20 repetition maximum), and control (CON) (n = 38). In the 3 training groups, subjects trained 3 times a week for 6 months, the CON group was asked to retain their sedentary lifestyle.

MAIN OUTCOME MEASURES

The acute exercise effect on BP was defined as the change of BP after an exhaustive stage test, compared with baseline. The chronic training effect on BP was determined as the change of resting BP after the 6-month training period.

RESULTS

For CET, a significant correlation between acute and chronic effects on systolic (r = 0.66, P = 0.001) and diastolic (r = 0.66, P = 0.001) BP was observed. For SET, a significant correlation (r = 0.45, P = 0.007) was found only for diastolic BP. No significant correlations were found for IET.

CONCLUSIONS

It can be assumed that postexercise hypotension is an easy-to-use predictor for the efficacy of CET to reduce BP, and may be a valuable tool for physicians to individualize prescribed training schedules for patients to reduce cardiovascular risk.

TRIAL REGISTRATION

www.clinicaltrials.gov; ID: NCT01263522.

Lifestyle genomics and the metabolic syndrome: A review of genetic variants that influence response to diet and exercise interventions

Metabolic syndrome (MetS) comprises a cluster of risk factors that includes central obesity, dyslipidemia, impaired glucose homeostasis and hypertension. Individuals with MetS have elevated risk of type 2 diabetes and cardiovascular disease; thus placing significant burdens on social and healthcare systems. Lifestyle interventions (comprised of diet, exercise or a combination of both) are routinely recommended as the first line of treatment for MetS. Only a proportion of people respond, and it has been assumed that psychological and social aspects primarily account for these differences. However, the etiology of MetS is multifactorial and stems, in part, on a person's genetic make-up. Numerous single nucleotide polymorphisms (SNPs) are associated with the various components of MetS, and several of these SNPs have been shown to modify a person's response to lifestyle interventions. Consequently, genetic variants can influence the extent to which a person responds to changes in diet and/or exercise. The goal of this review is to highlight SNPs reported to influence the magnitude of change in body weight, dyslipidemia, glucose homeostasis and blood pressure during lifestyle interventions aimed at improving MetS components. Knowledge regarding these genetic variants and their ability to modulate a person's response will provide additional context for improving the effectiveness of personalized lifestyle interventions that aim to reduce the risks associated with MetS.

IMPACTO DO EXERCÍCIO CONTÍNUO E INTERVALADO NA RESPOSTA AUTONÔMICA E PRESSÓRICA EM 24 HORAS

RESUMO Introdução: Exercícios físicos aeróbicos contínuos são os mais relacionados com a hipotensão pós-exercício. No entanto, são escassas as informações sobre o impacto do exercício intervalado sobre a resposta pressórica de 24 horas. Objetivo: Comparar as respostas pressóricas subagudas e agudas em uma sessão de exercício aeróbico contínuo e intervalado e identificar possíveis modulações em indicadores de atividade autonômica em adultos normotensos. Métodos: Submeteram-se 25 adultos normotensos saudáveis a três sessões experimentais: controle (30 minutos em repouso), exercício contínuo (30 min. - 60%-70% da FCres) e exercício intervalado (6 sessões de 5 minutos com intervalos de 2 min. - 60-70% da FCres) e seus parâmetros cardiovasculares foram monitorados por 24 horas após as sessões. Para comparação dos dados, foi utilizada a ANOVA para medidas repetidas, seguida de suas hipóteses. Resultados: No acompanhamento subagudo foi identificada redução significativa (P < 0,05) da pressão arterial sistólica somente após a sessão de exercício contínuo em comparação com a sessão de repouso (115 ± 2 mmHg vs. 112 ± 2 mmHg) e à sessão controle (119 ± 2 mmHg vs. 112 ± 2 mmHg). Não se identificou redução da pressão arterial ambulatorial em nenhuma das sessões experimentais. Os indicadores autonômicos parassimpáticos (RMSSD e pNN50) permaneceram reduzidos após 30 minutos em ambas as sessões de exercício. Conclusão: Uma única sessão de exercício aeróbico contínuo causa redução subaguda da pressão arterial em adultos normotensos. A sessão única de exercício aeróbico contínuo e intervalado não promove redução da pressão arterial ambulatorial na média nos períodos intermediários de sono e vigília.

Deep-targeted exon sequencing reveals renal polymorphisms associate with postexercise hypotension among African Americans

We found variants from the Angiotensinogen-Converting Enzyme (ACE), Angiotensin Type 1 Receptor (AGTR1), Aldosterone Synthase (CYP11B2), and Adducin (ADD1) genes exhibited intensity-dependent associations with the ambulatory blood pressure (BP) response following acute exercise, or postexercise hypotension (PEH). In a validation cohort, we sequenced exons from these genes for their associations with PEH Obese (30.9 ± 3.6 kg m-2) adults (n = 23; 61% African Americans [AF], 39% Caucasian) 42.0 ± 9.8 years with hypertension (139.8 ± 10.4/84.6 ± 6.2 mmHg) completed three random experiments: bouts of vigorous and moderate intensity cycling and control. Subjects wore an ambulatory BP monitor for 19 h. We performed deep-targeted exon sequencing using the Illumina TruSeq Custom Amplicon kit. Variant genotypes were coded as number of minor alleles (#MA) and selected for further statistical analysis based upon Bonferonni or Benjamini-Yekutieli multiple testing corrected p-values under time adjusted linear models for 19 hourly BP measurements per subject. After vigorous intensity over 19 h among ACE, AGTR1, CYP11B2, and ADD1 variants passing multiple testing thresholds, as the #MA increased, systolic (SBP) and/or diastolic BP decreased 12 mmHg (P = 4.5E-05) to 30 mmHg (P = 6.4E-04) among AF only. In contrast, after moderate intensity over 19 h among ACE and CYP11B2 variants passing multiple testing thresholds, as the #MA increased, SBP increased 21 mmHg (P = 8.0E-04) to 22 mmHg (P = 8.2E-04) among AF only. In this replication study, ACE, AGTR1, CYP11B2, and ADD1 variants exhibited associations with PEH after vigorous, but not moderate intensity exercise among AF only. Renal variants should be explored further with a multi-level "omics" approach for associations with PEH among a large, ethnically diverse sample of adults with hypertension.

Angiotensin II Type 1 Receptor Gene A1166C Polymorphism Was Not Associated With Acute Coronary Syndrome in an Iranian Population

Background

There are very limited data for Iranian populations on the predisposing genetic factors for acute coronary syndrome (ACS).

Objectives

The objective of the present study was to investigate the association of the angiotensin II type 1 receptor (AT1R) gene polymorphism and ACS in an Iranian population.

Patients and Methods

This cross-sectional study was conducted among 263 subjects (97 men and 166 women). Patients (n = 128) aged 30 - 80 years with chest pain were recruited from the emergency department of Ghaem Hospital (Mashhad, Iran). A 12-lead electrocardiograph plus creatine kinase MB (CK-MB) levels were used as the basis for the diagnosis of myocardial ischemia. The control group was selected from age-matched healthy subjects (n = 135). Non-enzymatic kits were used for extraction of DNA from blood samples. Polymerase chain reaction (PCR) was performed to amplify the DNA fragments. For restriction fragment length polymorphism (RFLP) determination, the DdeI enzyme was used to digest the amplified DNA fragments. Statistical analyses were performed using SPSS version 13.0.

Results

There was no statistical difference in the genotype frequency of patients and healthy subjects with regard to age and gender (P > 0.05).

Conclusions

The AT1R A1166C polymorphism appeared not to be associated with the presence of ACS in the population studied.

Acute Effects of Exercise on Blood Pressure: A Meta-Analytic Investigation

Hypertension affects 25% of the world's population and is considered a risk factor for cardiovascular disorders and other diseases. The aim of this study was to examine the evidence regarding the acute effect of exercise on blood pressure (BP) using meta-analytic measures. Sixty-five studies were compared using effect sizes (ES), and heterogeneity and Z tests to determine whether the ES were different from zero. The mean corrected global ES for exercise conditions were -0.56 (-4.80 mmHg) for systolic BP (sBP) and -0.44 (-3.19 mmHg) for diastolic BP (dBP; z ≠ 0 for all; p < 0.05). The reduction in BP was significant regardless of the participant's initial BP level, gender, physical activity level, antihypertensive drug intake, type of BP measurement, time of day in which the BP was measured, type of exercise performed, and exercise training program (p < 0.05 for all). ANOVA tests revealed that BP reductions were greater if participants were males, not receiving antihypertensive medication, physically active, and if the exercise performed was jogging. A significant inverse correlation was found between age and BP ES, body mass index (BMI) and sBP ES, duration of the exercise's session and sBP ES, and between the number of sets performed in the resistance exercise program and sBP ES (p < 0.05). Regardless of the characteristics of the participants and exercise, there was a reduction in BP in the hours following an exercise session. However, the hypotensive effect was greater when the exercise was performed as a preventive strategy in those physically active and without antihypertensive medication.

Effect of exercise training on the renin-angiotensin-aldosterone system in healthy individuals: a systematic review and meta-analysis

The aim of this systematic review and meta-analysis was to evaluate the effect of exercise training on parameters of the renin-angiotensin-aldosterone system (RAAS) in healthy adults, and to investigate the relation with training induced changes in blood pressure. A systematic search was conducted and we included randomized controlled trials lasting ⩾4 weeks investigating the effects of exercise on parameters of the RAAS in healthy adults (age ⩾18 years) and published in a peer-reviewed journal up to December 2013. Fixed effects models were used and data are reported as weighted means and 95% confidence limits (CL). Eleven randomized controlled trials with a total of 375 individuals were included. Plasma renin activity was reduced after exercise training (n= 7 trials, standardized mean difference -0.25 (95% CL -0.5 to -0.001), P=0.049), whereas no effect was observed on serum aldosterone ((n= 3 trials; standardized mean difference -0.79 (-1.97 to +0.39)) or angiotensin II (n=3 trials; standardized mean difference -0.16 (-0.61 to +0.30). Significant reductions in systolic blood pressure -5.65 mm Hg (-8.12 to -3.17) and diastolic blood pressure -3.64 mm Hg (-5.4 to -1.91) following exercise training were observed. No relation was found between net changes in plasma renin activity and net changes in blood pressure (P>0.05). To conclude, although we observed a significant reduction in plasma renin activity following exercise training this was not related to the observed blood pressure reduction. Given the small number of studies and small sample sizes, larger well-controlled randomized studies are required to confirm our results and to investigate the potential role of the RAAS in the observed improvements in blood pressure following exercise training.

Influência do polimorfismo I/D do gene da eca na HPE de jovens normotensos

INTRODUÇÃO: A hipotensão pós-exercício (HPE) é considerada uma estratégia não farmacológica adotada para redução da pressão arterial (PA). Ademais, sabe-se que a presença de alguns polimorfismos genéticos influencia a resposta pressórica, como o I/D do gene da enzima conversora da angiotensina (ECA). Objetivo: Analisar a influência do polimorfismo I/D da ECA sobre a HPE após três diferentes intensidades de exercício em jovens normotensos e fisicamente ativos.MÉTODOS: Vinte e seis jovens saudáveis (DD = 11; ID/II = 15) realizaram uma sessão máxima de 1.600 metros, na pista de atletismo e outras três sessões experimentais (Sessão Moderada: 6% abaixo do limiar anaeróbio, Sessão Intensa: 6% acima do limiar anaeróbio e Sessão de Controle), com aferições prévias da PA, por 20 minutos e posteriores ao exercício por 60 minutos.RESULTADOS: Observou-se que o exercício moderado ocasionou HPE independentemente do grupo genotípico, sendo mais evidente para a pressão arterial sistólica nos momentos 45 minutos e 60 minutos (p ≤ 0,05). Verificou-se também que a característica gênica exerceu influência sobre a área abaixo da curva pressórica (p ≤ 0,005) sobre a pressão arterial diastólica, formada 1 hora após o exercício.CONCLUSÃO: Conclui-se que o exercício moderado ocasiona HPE em jovens normotensos e fisicamente ativos, independentemente do polimorfismo I/D no gene da ECA, sendo que esse polimorfismo exerce influência sobre a hipotensão diastólica, e os indivíduos portadores do alelo I apresentam maior decaimento da PA diastólica (PAD).

The blood pressure response to acute and chronic aerobic exercise: A meta-analysis of candidate gene association studies

OBJECTIVES

To meta-analyze candidate gene association studies on the change in blood pressure beyond the immediate post-exercise phase after versus before aerobic exercise.

DESIGN

Meta-analysis.

METHODS

A systematic search was conducted. Studies retrieved included acute (short-term or postexercise hypotension) or chronic (long-term or training) aerobic exercise interventions; and blood pressure measured before and after aerobic exercise training, or before and after exercise or control under ambulatory conditions by genotype. Effect sizes were determined for genotype and adjusted for sample features.

RESULTS

Qualifying studies (k=17, n=3524) on average included middle-aged, overweight men (44.2%) and women (55.8%) with prehypertension (134.9±11.7/78.6±9.5mmHg). Training interventions (k=12) were performed at 60.4±12.9% of maximum oxygen consumption (VO2max) for 41.9±12.5minsession(-1), 3.6±1.2daysweek(-1) for 15.7±7.6week; and post-exercise hypotension interventions (k=5) were performed at 53.5±14.4% VO2max for 38.5±5.4minsession(-1). Sample characteristics explained 54.2-59.0% of the variability in the blood pressure change after versus before acute exercise or control under ambulatory conditions, and 57.4-67.1% of the variability in the blood pressure change after versus before training (p<0.001). Only angiotensinogen M235T (rs699) associated with the change in diastolic blood pressure after versus before training (R(2)=0.1%, p=0.05), but this association did not remain statistically significant after adjustment for multiple comparisons.

CONCLUSIONS

Sample characteristics explained most of the variability in the change of BP beyond the immediate post-exercise phase after versus before acute and chronic aerobic exercise. Angiotensinogen M235T (rs699) was the only genetic variant that associated with the change in diastolic blood pressure after versus before training, accounting for <1% of the variance.

Comportamento da pressão arterial em homens pré-hipertensos participantes em um programa regular de natação

INTRODUÇÃO: A natação tem sido recomendada como tipo de atividade física para a prevenção, tratamento e controle da hipertensão arterial. OBJETIVO: Analisar os efeitos da prática regular de natação sobre a pressão arterial de adultos pré-hipertensos. MÉTODOS: A amostra foi composta por 36 homens pré-hipertensos divididos em dois grupos: Experimental - GE (n=24, 40,60±9,36 anos) e Controle - GC (n=12, 40,57±8,05 anos). O GE realizou um programa regular de natação, com três sessões semanais de 45 min, durante 12 semanas, enquanto o GC não alterou seus hábitos alimentares e permaneceu sem praticar atividade física no período. O procedimento estatístico utilizado para verificar as diferenças entre as médias antes e depois de 12 semanas do programa regular de natação foi o teste-t de Student. O estudo admitiu o nível de p < 0.05 para a significância estatística. RESULTADOS: O grupo GE apresentou diferenças estatisticamente significativas nas variáveis analisadas quando comparadas com o GC, tanto na pressão arterial sistólica, PAS (Δ = - 5,89 mmHg, p = 0,00), como na pressão arterial diastólica, PAD (Δ = - 5,15mmHg, p = 0,00). CONCLUSÃO: Os resultados mostram que um programa regular de natação provoca reduções significativas na pressão arterial em repouso em homens pré-hipertensos.

Hypotensive response magnitude and duration in hypertensives: continuous and interval exercise

BACKGROUND

Although exercise training is known to promote post-exercise hypotension, there is currently no consistent argument about the effects of manipulating its various components (intensity, duration, rest periods, types of exercise, training methods) on the magnitude and duration of hypotensive response.

OBJECTIVE

To compare the effect of continuous and interval exercises on hypotensive response magnitude and duration in hypertensive patients by using ambulatory blood pressure monitoring (ABPM).

METHODS

The sample consisted of 20 elderly hypertensives. Each participant underwent three ABPM sessions: one control ABPM, without exercise; one ABPM after continuous exercise; and one ABPM after interval exercise. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR) and double product (DP) were monitored to check post-exercise hypotension and for comparison between each ABPM.

RESULTS

ABPM after continuous exercise and after interval exercise showed post-exercise hypotension and a significant reduction (p < 0.05) in SBP, DBP, MAP and DP for 20 hours as compared with control ABPM. Comparing ABPM after continuous and ABPM after interval exercise, a significant reduction (p < 0.05) in SBP, DBP, MAP and DP was observed in the latter.

CONCLUSION

Continuous and interval exercise trainings promote post-exercise hypotension with reduction in SBP, DBP, MAP and DP in the 20 hours following exercise. Interval exercise training causes greater post-exercise hypotension and lower cardiovascular overload as compared with continuous exercise.

Exercise as medicine: Role in the management of primary hypertension

Primary hypertension affects ∼1 in 5 Canadians and significantly increases the risk of myocardial infarction, stroke, heart failure, and early mortality. Guidelines for the management of hypertension recommend lifestyle modifications (e.g., increased physical activity, smoking cessation, moderate alcohol consumption, improved dietary choices) as the frontline strategy to prevent and manage high blood pressure (BP). In particular, acute and chronic aerobic exercise has consistently been shown to reduce resting and ambulatory BP, with the largest effects in hypertensive patients. Current guidelines recommend 30–60 min of moderate- to vigorous-intensity aerobic exercise 4–7 days per week, in addition to activities of daily living. The role of resistance training in the management of hypertension is less clear, although available data suggests resistance exercise can be performed safely without risk of increasing BP or adverse events. Presently, resistance exercise (8–10 exercises, 1–2 set(s) of 10–15 repetitions, 2–3 days/week) is advocated only as an adjunct exercise modality. Patients desiring to begin an exercise program should complete the Physical Activity Readiness Questionnaire (PAR-Q or PAR-Q+) or as required, the Electronic Physical Activity Readiness Medical Examination (ePARmed-X) or Physician Clearance Form in consultation with their clinician and (or) trained exercise professional. A greater emphasis on utilizing exercise as medicine will produce positive nonpharmacologic benefits for hypertensive patients and improve overall cardiovascular risk profiles.

Neuro-hormonal effects of physical activity in the elderly

Thanks to diagnostic and therapeutic advances, the elderly population is continuously increasing in the western countries. Accordingly, the prevalence of most chronic age-related diseases will increase considerably in the next decades, thus it will be necessary to implement effective preventive measures to face this epidemiological challenge. Among those, physical activity exerts a crucial role, since it has been proven to reduce the risk of cardiovascular diseases, diabetes, obesity, cognitive impairment and cancer. The favorable effects of exercise on cardiovascular homeostasis can be at least in part ascribed to the modulation of the neuro-hormonal systems implicated in cardiovascular pathophysiology. In the elderly, exercise has been shown to affect catecholamine secretion and biosynthesis, to positively modulate the renin-angiotensin-aldosterone system and to reduce the levels of plasma brain natriuretic peptides. Moreover, drugs modulating the neuro-hormonal systems may favorably affect physical capacity in the elderly. Thus, efforts should be made to actually make physical activity become part of the therapeutic tools in the elderly.

Acute and chronic effects of resistance exercise on blood pressure in elderly women and the possible influence of ACE I/D polymorphism

This study investigated the chronic effect of blood pressure (BP) and post-exercise hypotension (PEH) during resistance training (RT) and its relation with the angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism in hypertensive elderly women. Participants were divided into two groups: an experimental group (EG) with exercise and a control group (CG) without exercise. The EG performed one adaptation month and one repetition maximum load (1RM) test at the end of this period. After the first month, the EG conducted a three-month program of RT at 60%, 70%, and 80% of 1RM, respectively, for each month. The CG was evaluated at the end of each month. Systolic (SBP) and diastolic (DBP) blood pressure (Microlife BP 3AC1-1) were measured, with the subject in a seated position, during an acute session for both GE and CG as follows: every 5 minutes for 20 minutes at pre-exercise rest, immediately after the resistance exercise and control, and every 15 minutes during 1 hour of recovery after exercise and CG. Analysis of covariance showed reduction in SBP and DBP (P ≤ 0.05) rest values after the RT program. PEH was observed only for the EG in acute sessions, for SBP after the second and third months (P ≤ 0.05), and for DBP after the second and fourth months (P ≤ 0.05). No significant differences in main effects and interaction effects between blood pressure and ACE I/D were observed. The occurrence of chronic reduction of blood pressure and PEH through EG may have a protective effect on the cardiovascular system with no ACE I/D polymorphism influence for this population.

Association of cardiovascular response to an acute resistance training session with the ACE gene polymorphism in sedentary women: a randomized trial

Background

The aim of the present study was to verify the effects of an acute resistance training (RT) session and insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) on systolic (SBP), diastolic (DBP) and mean blood pressure (MBP), and heart rate (HR).

Methods

The sample consisted of 27 sedentary women (33.3 ± 8.2 yrs; 69.1 ± 13.8 kg; 1.57 ± 0.05 m; 27.6 ± 5.1 kg/m²) divided into two groups according to their polymorphism I/D (DD = 9; II + ID = 18). Volunteers underwent two experimental sessions: RT – an acute session performed with three sets at 60% of one-repetition maximum (1RM) interspersed with 1 minute rest interval between exercises and sets, and a control session (CON) in which they remained seated for 30 minutes in the laboratory. SBP, DBP, MBP and HR were measured before exercise and during one hour every 10 minutes after sessions, in the seated position. A two-way ANOVA for repeated measures with Tukey’s post hoc test was used for the intra and inter-group comparisons.

Results

There were no statistically significant differences on SBP, DBP and MBP after the experimental protocols, and no effect of ACE polymorphism (P > 0.05). However, comparing CON versus exercise effect size values (ES), homozygotic carriers of the allele D presented a drop in SBP which was considered moderate, while in allele I carriers it was small, 30 minutes after exercise. In MBP, homozygotic D carriers exhibited a large ES 20 minutes post-exercise. HR was higher at 10, 20 and 30 minutes after exercise as compared to pre-exercise only for carriers of the I allele (P < 0.05).

Conclusions

Therefore, an acute RT session reduces clinical BP. In addition to this; it seems that ACE polymorphism had some influence on cardiovascular response to exercise.

Trial Registration

RBR-6GDYVZ

Association between postexercise hypotension and long-term training-induced blood pressure reduction: a pilot study

OBJECTIVE

The interindividual variability in the efficacy of regular endurance exercise to lower blood pressure is high. Therefore, to optimize training prescriptions, predictors would be desirable. The main hypothesis of the present study was an association between postexercise hypotension after an exhaustive exercise test and chronic blood pressure reductions in response to an endurance training program.

DESIGN

Uncontrolled prospective training study.

SETTING

University department.

PARTICIPANTS

Healthy untrained subjects were recruited by flyers. Inclusion criteria were age 30 to 60 years, body mass index 25 to 35 kg/m(2), untrained status (<1 hour/week regular activity; V[Combining Dot Above]O(2max) < 45 mL·min(-1)·kg(-1)), blood pressure 150/95 mm Hg, nonsmoker; 14 subjects were included, 12 could be analyzed.

INTERVENTION

Walking/running 4 times per week at 60% heart rate reserve for 4 weeks.

MAIN OUTCOME MEASURES

Difference in blood pressure from the initial resting value to 1 and 24 hours after the initial test (acute) and the resting value before the final test (chronic), respectively.

RESULTS

Initial resting systolic blood pressure was 134 ± 18 mm Hg. Values were significantly reduced at all time points thereafter (1 hour: 125 ± 13 mm Hg; 24 hours: 128 ± 12 mm Hg; final: 125 ± 18 mm Hg). Acute and chronic changes correlated significantly (1 hour: P = 0.003; r = 0.77; 24 hours: P = 0.017; r = 0.67). Results for diastolic blood pressure were comparable yet less pronounced.

CONCLUSIONS

The magnitude of postexercise hypotension is a promising candidate for the prediction of individual blood pressure-related training efficacy. Easily determined, it might be used to improve training prescriptions. However, further studies are needed to assess predictive accuracy.

Comportamento cardiovascular após o exercício resistido realizado de diferentes formas e volumes de trabalho

OBJETIVO: Verificar as respostas cardiovasculares após o exercício resistido realizado de diferentes formas e volumes de trabalho. MÉTODOS: Dez homens saudáveis realizaram em dias diferentes e aleatoriamente sessões de oito exercícios resistidos (18 repetições e 40% de 1RM) e uma sessão controle. As sessões de exercícios foram executadas com uma série em circuito (1CIRC), três séries em circuito (3CIRC), uma série de forma convencional (1CONV) e três séries de forma convencional (3CONV). A pressão arterial (PA) e a variabilidade da frequência cardíaca (VFC) foram medidas em repouso e por uma hora após as sessões. RESULTADOS: Considerando a média do período de monitorização, em relação à PA sistólica, somente a sessão 3CIRC (-9,4 ± 3,0mmHg; P = 0,02) promoveu reduções em relação à sessão controle. Já para a PA diastólica, as sessões 1CIRC (-5,7 ± 1,8mmHg; P = 0,005), 3CIRC (-8,4 ± 1,6mmHg; P = 0,0002) e 3CONV (-8,6 ± 2,2mmHg; P = 0,0001) ocasionaram reduções em relação à sessão controle. De forma idêntica, a PA média permaneceu reduzida em relação ao controle após as sessões 1CIRC (-5,0 ± 1,8mmHg; P = 0,02), 3CIRC (-8,7 ± 1,6mmHg; P = 0,0002) e 3CONV (-7,9 ± 1,9mmHg; P = 0,0006).Em relação à FC, a sessão 3CIRC mostrou valores superiores relação às sessões 1CONV (P = 0,001) e 3CONV (P = 0,04). A razão entre os componentes LF/HF da VFC também foi superior em relação ao controle na sessão 3CIRC. CONCLUSÃO: As sessões envolvendo mais séries de exercícios ocasionaram reduções na PA de maneira similar. Porém, a sessão 3CIRC acarretou maior esforço cardíaco pós-esforço.

Pressão arterial e variabilidade de frequência cardíaca após o exercício aeróbio e com pesos realizados na mesma sessão

OBJETIVO: Verificar o comportamento da PA sistólica (PAS), diastólica (PAD), média (PAM), frequência cardíaca (FC) e a variabilidade da frequência cardíaca (VFC) após sessões de exercício aeróbio e com pesos combinadas em diferentes ordens. MÉTODOS: Nove homens normotensos realizaram aleatoriamente em dias diferentes uma sessão de exercício aeróbio (cicloergômetro; 60% do <img border=0 src="/img/revistas/rbme/v18n1/v.jpg" align=absbottom>O2pico; 50 min) seguido pelo exercício com pesos (oito exercícios, três séries de 10-15 repetições, 60% de 1RM) e outra sessão iniciada pelo exercício com pesos seguido pelo exercício aeróbio. PA, FC e VFC foram medidas antes do exercício e durante 60 min após o término das sessões em intervalos de 10 min. RESULTADOS: Não foram observadas diferenças entre as sessões experimentais. A média dos 60 min do período de acompanhamento foi menor para a PAS (repouso = 121,3 ± 3,9; pós = 114,4 ± 2,1mmHg) e maior para a FC (repouso = 75,8 ± 4,3; pós = 89,5 ± 5,8bpm) na sessão iniciada pelo exercício aeróbio. Em contrapartida, não houve diferenças na média do período de recuperação para a PAD, PAM e VFC. CONCLUSÃO: Como não houve diferenças entre as variáveis das diferentes sessões, conclui-se que a ordem de execução dos exercícios aeróbio e com pesos não interfere nas respostas cardiovasculares e autonômicas após o esforço de sujeitos normotensos.

The higher exercise intensity and the presence of allele I of ACE gene elicit a higher post-exercise blood pressure reduction and nitric oxide release in elderly women: an experimental study

BACKGROUND

The absence of the I allele of the angiotensin converting enzyme (ACE) gene has been associated with higher levels of circulating ACE, lower nitric oxide (NO) release and hypertension. The purposes of this study were to analyze the post-exercise salivary nitrite (NO2-) and blood pressure (BP) responses to different exercise intensities in elderly women divided according to their ACE genotype.

METHODS

Participants (n = 30; II/ID = 20 and DD = 10) underwent three experimental sessions: incremental test - IT (15 watts workload increase/3 min) until exhaustion; 20 min exercise 90% anaerobic threshold (90% AT); and 20 min control session without exercise. Volunteers had their BP and NO2- measured before and after experimental sessions.

RESULTS

Despite both intensities showed protective effect on preventing the increase of BP during post-exercise recovery compared to control, post-exercise hypotension and increased NO2- release was observed only for carriers of the I allele (p < 0.05).

CONCLUSION

Genotypes of the ACE gene may exert a role in post-exercise NO release and BP response.

The additive blood pressure lowering effects of exercise intensity on post-exercise hypotension

BACKGROUND

Evidence contends lower levels of physical exertion reduce blood pressure (BP) as effectively as more rigorous levels. We compared the effects of low (40% peak oxygen consumption, Vo(2)peak), moderate (60% Vo(2)peak), and vigorous (100% Vo(2)peak) exercise intensity on the BP response immediately following aerobic exercise. We also examined clinical correlates of the BP response.

METHODS

Subjects were 45 men (mean +/- SEM, 43.9 +/- 1.4 years) with elevated awake ambulatory BP (ABP, 144.5 +/- 1.5/85.4 +/- 1.2 mm Hg). Men completed four randomly assigned experiments: non-exercise control and three exercise bouts at low, moderate, and vigorous intensity. All experiments began with a baseline period of seated rest. Subjects left the laboratory wearing an ABP monitor.

RESULTS

Systolic ABP increased 2.8 +/- 1.6 mm Hg less after low, 5.4 +/- 1.4 mm Hg less after moderate, and 11.7 +/- 1.5 mm Hg less after vigorous than control over 9 h (P < .001). Diastolic ABP decreased 1.5 +/- 1.2 mm Hg more after low, 2.0 +/- 1.0 mm Hg more after moderate, and 4.9 +/- 1.3 mm Hg more after vigorous versus control over 9 h (P < .010). Baseline correlates of the systolic ABP post-exercise response to vigorous were fasting glucose (r = -0.415), C-reactive protein (r = -0.362), renin (r = -0.348), fasting insulin (r = 0.310), and fasting low density lipoprotein (r = -0.298) (R(2) = 0.400, P = .002). Baseline correlates of the diastolic ABP post-exercise response to vigorous were Vo(2)peak (r = -0.431), fasting low density lipoprotein (r = -0.431), renin (r = -0.411), fibrinogen (r = 0.369), and fasting glucose (r = -0.326) (R(2) = 0.429, P < .001).

CONCLUSIONS

The antihypertensive effects of exercise intensity occurred in dose response fashion. Clinicians should weigh the benefits and risks of prescribing vigorous exercise intensity for those with hypertension on an individual basis.

Acute and chronic effects of aerobic and resistance exercise on ambulatory blood pressure

Hypertension is a ubiquitous and serious disease. Regular exercise has been recommended as a strategy for the prevention and treatment of hypertension because of its effects in reducing clinical blood pressure; however, ambulatory blood pressure is a better predictor of target-organ damage than clinical blood pressure, and therefore studying the effects of exercise on ambulatory blood pressure is important as well. Moreover, different kinds of exercise might produce distinct effects that might differ between normotensive and hypertensive subjects.The aim of this study was to review the current literature on the acute and chronic effects of aerobic and resistance exercise on ambulatory blood pressure in normotensive and hypertensive subjects. It has been conclusively shown that a single episode of aerobic exercise reduces ambulatory blood pressure in hypertensive patients. Similarly, regular aerobic training also decreases ambulatory blood pressure in hypertensive individuals. In contrast, data on the effects of resistance exercise is both scarce and controversial. Nevertheless, studies suggest that resistance exercise might acutely decrease ambulatory blood pressure after exercise, and that this effect seems to be greater after low-intensity exercise and in patients receiving anti-hypertensive drugs. On the other hand, only two studies investigating resistance training in hypertensive patients have been conducted, and neither has demonstrated any hypotensive effect. Thus, based on current knowledge, aerobic training should be recommended to decrease ambulatory blood pressure in hypertensive individuals, while resistance exercise could be prescribed as a complementary strategy.

Exercise Prescription for the Prevention and Management of Hypertension

Regular physical activity is known to reduce blood pressure in 75% of individuals with hypertension and is a key component of lifestyle therapy for the prevention and management of hypertension. However, the frequency, intensity, duration, and mode of activity play a role in the magnitude and duration of blood pressure reduction. Aerobic activity is the preferred type of activity to lower blood pressure. Acute, moderate-intensity aerobic activity (40%-60% VO2max ) can decrease blood pressure by 5 to 7 mm Hg for up to 22 hours postexercise, so participation in aerobic activity is recommended on most, if not all, days of the week. The recommended duration for aerobic activity is 30 to 60 minutes of continuous or intermittent activity. Resistance activity results in a 3-mm Hg decrease in blood pressure and should supplement the aerobic activity. Low- to moderate-intensity resistance training (30%-40% of a 1—repetition maximum [1RM] for upper body exercises and 50%-60% 1RM for lower body exercises) is recommended 2 to 3 d/wk. The volume of resistance training for blood pressure reduction is 1 to 3 sets of 10 to 15 repetitions for 8 to 10 exercises that target large muscle groups (thighs, hips, back, chest, arms, and abdominals). When prescribing physical activity for the prevention or management of hypertension, it is important to know that certain populations respond differently to activity and that certain medications can inhibit physical performance.

The human gene map for performance and health-related fitness phenotypes: the 2006-2007 update

This update of the human gene map for physical performance and health-related fitness phenotypes covers the research advances reported in 2006 and 2007. The genes and markers with evidence of association or linkage with a performance or a fitness phenotype in sedentary or active people, in responses to acute exercise, or for training-induced adaptations are positioned on the map of all autosomes and sex chromosomes. Negative studies are reviewed, but a gene or a locus must be supported by at least one positive study before being inserted on the map. A brief discussion on the nature of the evidence and on what to look for in assessing human genetic studies of relevance to fitness and performance is offered in the introduction, followed by a review of all studies published in 2006 and 2007. The findings from these new studies are added to the appropriate tables that are designed to serve as the cumulative summary of all publications with positive genetic associations available to date for a given phenotype and study design. The fitness and performance map now includes 214 autosomal gene entries and quantitative trait loci plus seven others on the X chromosome. Moreover, there are 18 mitochondrial genes that have been shown to influence fitness and performance phenotypes. Thus,the map is growing in complexity. Although the map is exhaustive for currently published accounts of genes and exercise associations and linkages, there are undoubtedly many more gene-exercise interaction effects that have not even been considered thus far. Finally, it should be appreciated that most studies reported to date are based on small sample sizes and cannot therefore provide definitive evidence that DNA sequence variants in a given gene are reliably associated with human variation in fitness and performance traits.

Hipotensão pós-exercício aeróbio: uma revisão sistemática

Diversos estudos investigaram os efeitos hipotensores após uma sessão de exercício aeróbio em humanos. No entanto, vários aspectos permanecem obscuros em relação à hipotensão pós-exercício (HPE), uma vez que diversas variáveis podem influenciar a resposta hipotensora, como intensidade, duração, tipo de exercício, estado clínico, faixa etária, etnia, sexo e estado de treinamento. Nesse sentido, o objetivo do presente estudo foi revisar sistematicamente a literatura, relacionando as principais variáveis da prescrição de uma sessão de exercício aeróbio e a HPE, assim como apresentar os possíveis mecanismos envolvidos. Foram encontrados 55 estudos que abrangeram a temática HPE e exercício aeróbio em humanos. A ocorrência da HPE está bem estabelecida na literatura, já que vários estudos identificaram reduções da pressão arterial em normotensos e hipertensos. Porém, os possíveis moduladores das respostas hipotensoras, como intensidade e duração da sessão de exercício, ainda são contraditórios. Em relação ao tipo de exercício, porém, existem indicativos de que os realizados de forma intermitente e que utilizam maior massa muscular podem acarretar maior HPE. Além disso, hipertensos devem apresentar maior magnitude e duração da HPE. Contudo, existem lacunas em relação aos diversos mecanismos fisiológicos envolvidos, que parecem ser diferentes entre normotensos e hipertensos.

A comparison of the genetic and clinical profile of men that respond and do not respond to the immediate antihypertensive effects of aerobic exercise

We compared the genetic and clinical profile of men who lower and do not lower blood pressure (BP) after acute aerobic exercise. Volunteers were 45 men (Mean ± SEM, 43.5 ± 1.5 yr) with high BP (145.7 ± 1.5/85.7 ± 1.1 mmHg). They completed three experiments: nonexercise control and two cycle exercise sessions at 40% and 60% peak oxygen consumption, and were then instrumented to an ambulatory BP monitor. Logistic regression determined the genetic and clinical profile of men who lowered BP after exercise (responders [ExR n = 36]); and those who did not (nonresponders [ExNR n = 9]). ExR had higher C-reactive protein (CRP), high-density lipoprotein (HDL), the metabolic syndrome, family history of hypertension, more renin-angiotensin system (RAS) common alleles, and α-adducin Trp(460) and endothelial nitric oxide synthase (ENOS) C(786) risk alleles. ExNR had lower CRP and HDL, did not have the metabolic syndrome and a family history of hypertension, had more RAS risk alleles, and had the α-adducin Gly460Gly and ENOS T786T genotypes. This model had a sensitivity of 97.1%, specificity of 75.0%, and accounted for 46.3%-74.4% of the BP response. These results suggest genetic and clinical information may eventually be used to characterize people who do and do not respond to exercise as antihypertensive therapy.

The metabolic syndrome and the immediate antihypertensive effects of aerobic exercise: a randomized control design

Background

The metabolic syndrome (Msyn) affects about 40% of those with hypertension. The Msyn and hypertension have a common pathophysiology. Exercise is recommended for their treatment, prevention and control. The influence of the Msyn on the antihypertensive effects of aerobic exercise is not known. We examined the influence of the Msyn on the blood pressure (BP) response following low (LIGHT, 40% peak oxygen consumption, VO₂peak) and moderate (MODERATE, 60% VO₂peak) intensity, aerobic exercise.

Methods

Subjects were 46 men (44.3 ± 1.3 yr) with pre- to Stage 1 hypertension (145.5 ± 1.6/86.3 ± 1.2 mmHg) and borderline dyslipidemia. Men with Msyn (n = 18) had higher fasting insulin, triglycerides and homeostasis model assessment (HOMA) and lower high density lipoprotein than men without Msyn (n = 28) (p < 0.01). Subjects consumed a standard meal and 2 hr later completed one of three randomized experiments separated by 48 hr. The experiments were a non-exercise control session of seated rest and two cycle bouts (LIGHT and MODERATE). BP, insulin and glucose were measured before, during and after the 40 min experiments. Subjects left the laboratory wearing an ambulatory BP monitor for the remainder of the day. Repeated measure ANCOVA tested if BP, insulin and glucose differed over time among experiments in men without and with the Msyn with HOMA as a covariate. Multivariable regression analyses examined associations among BP, insulin, glucose and the Msyn.

Results

Systolic BP (SBP) was reduced 8 mmHg (p < 0.05) and diastolic BP (DBP) 5 mmHg (p = 0.052) after LIGHT compared to non-exercise control over 9 hr among men without versus with Msyn. BP was not different after MODERATE versus non-exercise control between Msyn groups (p ≥ 0.05). The factors accounting for 17% of the SBP response after LIGHT were baseline SBP (β = -0.351, r² = 0.123, p = 0.020), Msyn (β = 0.277, r² = 0.077, p = 0.069), and HOMA (β = -0.124, r² = 0.015, p = 0.424). Msyn (r² = 0.096, p = 0.036) was the only significant correlate of the DBP response after LIGHT.

Conclusion

Men without the Msyn respond more favorably to the antihypertensive effects of lower intensity, aerobic exercise than men with the Msyn. If future work confirms our findings, important new knowledge will be gained for the personalization of exercise prescriptions among those with hypertension and the Msyn.

Genome-wide association of echocardiographic dimensions, brachial artery endothelial function and treadmill exercise responses in the Framingham Heart Study

BACKGROUND

Echocardiographic left ventricular (LV) measurements, exercise responses to standardized treadmill test (ETT) and brachial artery (BA) vascular function are heritable traits that are associated with cardiovascular disease risk. We conducted a genome-wide association study (GWAS) in the community-based Framingham Heart Study.

METHODS

We estimated multivariable-adjusted residuals for quantitative echocardiography, ETT and BA function traits. Echocardiography residuals were averaged across 4 examinations and included LV mass, diastolic and systolic dimensions, wall thickness, fractional shortening, left atrial and aortic root size. ETT measures (single exam) included systolic blood pressure and heart rate responses during exercise stage 2, and at 3 minutes post-exercise. BA measures (single exam) included vessel diameter, flow-mediated dilation (FMD), and baseline and hyperemic flow responses. Generalized estimating equations (GEE), family-based association tests (FBAT) and variance-components linkage were used to relate multivariable-adjusted trait residuals to 70,987 SNPs (Human 100K GeneChip, Affymetrix) restricted to autosomal SNPs with minor allele frequency > or =0.10, genotype call rate > or =0.80, and Hardy-Weinberg equilibrium p > or = 0.001.

RESULTS

We summarize results from 17 traits in up to 1238 related middle-aged to elderly men and women. Results of all association and linkage analyses are web-posted at http://ncbi.nlm.nih.gov/projects/gap/cgi-bin/study.cgi?id=phs000007 webcite. We confirmed modest-to-strong heritabilities (estimates 0.30-0.52) for several Echo, ETT and BA function traits. Overall, p < 10(-5) in either GEE or FBAT models were observed for 21 SNPs (nine for echocardiography, eleven for ETT and one for BA function). The top SNPs associated were (GEE results): LV diastolic dimension, rs1379659 (SLIT2, p = 1.17*10(-7)); LV systolic dimension, rs10504543 (KCNB2, p = 5.18*10(-6)); LV mass, rs10498091 (p = 5.68*10(-6)); Left atrial size, rs1935881 (FAM5C, p = 6.56*10(-6)); exercise heart rate, rs6847149 (NOLA1, p = 2.74*10(-6)); exercise systolic blood pressure, rs2553268 (WRN, p = 6.3*10(-6)); BA baseline flow, rs3814219 (OBFC1, 9.48*10(-7)), and FMD, rs4148686 (CFTR, p = 1.13*10(-5)). Several SNPs are reasonable biological candidates, with some being related to multiple traits suggesting pleiotropy. The peak LOD score was for LV mass (4.38; chromosome 5); the 1.5 LOD support interval included NRG2.

CONCLUSION

In hypothesis-generating GWAS of echocardiography, ETT and BA vascular function in a moderate-sized community-based sample, we identified several SNPs that are candidates for replication attempts and we provide a web-based GWAS resource for the research community.

The alpha-adducin Gly460Trp polymorphism and the antihypertensive effects of exercise among men with high blood pressure

The alpha-adducin Gly460Trp polymorphism alters renal sodium transport and is associated with hypertension. Despite the immediate sodium- and volume-depleting effects of aerobic exercise, the influence of the alpha-adducin Gly460Trp polymorphism on PEH (postexercise hypotension) has not been studied. In the present study we examined the effects of the alpha-adducin Gly460Trp polymorphism on PEH among 48 men (42.6+/-1.6 years; mean+/-S.E.M.) with high BP (blood pressure; 144.0+/-1.7/84.7+/-1.1 mmHg). Subjects completed three experiments: non-exercise control and two cycle exercise sessions at 40% (light exercise) and 60% (moderate exercise) of maximal oxygen consumption. Subjects left the laboratory wearing an ambulatory BP monitor. PCR and restriction enzyme digestion determined the genotypes. No subjects had the Trp460Trp genotype due to the low frequency of 5% in the population. Repeated measure ANCOVA tested whether BP differed over time between experimental conditions and genotypes (Gly460Gly, n=36; Gly460Trp, n=12). Among Gly460Gly genotypes, SBP (systolic BP) was reduced by 5.2+/-1.4 mmHg after moderate exercise compared with non-exercise controls over 9 h (P<0.01). Among Gly460Trp genotypes, SBP was lowered by 7.8+/-2.3 mmHg; after light exercise compared with non-exercise controls over 9 h (P<0.05). The SBP reductions after light exercise (0.6+/-1.3 compared with 7.8+/-2.3 mmHg; P<0.05) but not moderate exercise (5.2+/-1.4 compared with 3.8+/-2.4 mmHg; P> or =0.05) differed between the Gly460Gly and Gly460Trp genotypes respectively. Men with Gly460Gly had a reduced SBP after moderate exercise, whereas men with Gly460Trp had a reduced SBP after light exercise. However, only the SBP reductions after light exercise differed between genotypes. Our findings indicate that the alpha-adducin Gly460Trp genotype may be useful in identifying men who have a reduced BP after lower intensity aerobic exercise.

Heritability, Linkage, and Genetic Associations of Exercise Treadmill Test Responses

Background— The blood pressure (BP) and heart rate responses to exercise treadmill testing predict incidence of cardiovascular disease, but the genetic determinants of hemodynamic and chronotropic responses to exercise are largely unknown.

Methods and Results— We assessed systolic BP, diastolic BP, and heart rate during the second stage of the Bruce protocol and at the third minute of recovery in 2982 Framingham Offspring participants (mean age 43 years; 53% women). With use of residuals from multivariable models adjusted for clinical correlates of exercise treadmill testing responses, we estimated the heritability (variance-components methods), genetic linkage (multipoint quantitative trait analyses), and association with 235 single-nucleotide polymorphisms in 14 candidate genes selected a priori from neurohormonal pathways for their potential role in exercise treadmill testing responses. Heritability estimates for heart rate during exercise and during recovery were 0.32 and 0.34, respectively. Heritability estimates for BP variables during exercise were 0.25 and 0.26 (systolic and diastolic BP) and during recovery, 0.16 and 0.13 (systolic and diastolic BP), respectively. Suggestive linkage was found for systolic BP during recovery from exercise (locus 1q43−44, log-of-the-odds score 2.59) and diastolic BP during recovery from exercise (locus 4p15.3, log-of-the-odds score 2.37). Among 235 single-nucleotide polymorphisms tested for association with exercise treadmill testing responses, the minimum nominal probability value was 0.003, which was nonsignificant after adjustment for multiple testing.

Conclusions— Hemodynamic and chronotropic responses to exercise are heritable and demonstrate suggestive linkage to select loci. Genetic mapping with newer approaches such as genome-wide association may yield novel insights into the physiological responses to exercise.

Dietary calcium intake and renin angiotensin system polymorphisms alter the blood pressure response to aerobic exercise: a randomized control design

Background

Dietary calcium intake and the renin angiotensin system (RAS) regulate blood pressure (BP) by modulating calcium homeostasis. Despite similar BP regulatory effects, the influence of dietary calcium intake alone and combined with RAS polymorphisms on the BP response following acute aerobic exercise (i.e., postexercise hypotension) has not been studied. Thus, we examined the effect of dietary calcium intake and selected RAS polymorphisms on postexercise hypotension.

Methods

Subjects were men (n = 50, 43.8 ± 1.3 yr) with high BP (145.3 ± 1.5/85.9 ± 1.1 mm Hg). They completed three experiments: non-exercise control and two cycle bouts at 40% and 60% of maximal oxygen consumption (VO₂max). Subjects provided 3 d food records on five protocol-specific occasions. Dietary calcium intake was averaged and categorized as low (<880 mg/d = LowCa) or high (≥ 880 mg/d = HighCa). RAS polymorphisms (angiotensin converting enzyme insertion/deletion, ACE I/D; angiotensin II type 1 receptor, AT₁R A/C) were analyzed with molecular methods. Genotypes were reduced from three to two: ACE II/ID and ACE DD; or AT₁R AA and AT₁R CC/AC. Repeated measure ANCOVA tested if BP differed among experiments, dietary calcium intake level and RAS polymorphisms.

Results

Systolic BP (SBP) decreased 6 mm Hg after 40% and 60% VO₂max compared to non-exercise control for 10 h with LowCa (p < 0.01), but not with HighCa (p ≥ 0.05). Under these conditions, diastolic BP (DBP) did not differ between dietary calcium intake levels (p ≥ 0.05). With LowCa, SBP decreased after 60% VO₂max versus non-exercise control for 10 h among ACE II/ID (6 mm Hg) and AT₁R AA (8 mm Hg); and by 8 mm Hg after 40% VO₂max among ACE DD and AT₁R CC/CA (p < 0.01). With HighCa, SBP (8 mm Hg) and DBP (4 mm Hg) decreased after 60% VO₂max compared to non-exercise control for 10 h (p < 0.05), but not after 40% VO₂max (p ≥ 0.05).

Conclusion

SBP decreased after exercise compared to non-exercise control among men with low but not high dietary calcium intake. Dietary calcium intake interacted with the ACE I/D and AT₁R A/C polymorphisms to further modulate postexercise hypotension. Interactions among dietary calcium intake, exercise intensity and RAS polymorphisms account for some of the variability in the BP response to exercise.

Multilocus analyses of Renin-Angiotensin-aldosterone system gene variants on blood pressure at rest and during behavioral stress in young normotensive subjects

The renin-angiotensin-aldosterone system (RAAS) is a proteolytic cascade that regulates and maintains blood pressure (BP). This study aimed to explore the interactive and integrative effects of multiple RAAS polymorphisms on BP at rest and during behavioral stress in a normotensive population. A total of 920 young white and black twins (age: 12 to 30 years; 45% blacks) was subjected to three 10-minute stress tasks. Thirteen potential functional polymorphisms from 4 major RAAS genes were genotyped. We performed multilocus prediction allowing for genetic modification effects (gene-gene, gene-gender, gene-ethnicity, and gene-body mass index) using Multivariate Adaptive Regression Splines and generalized estimating equations. Single polymorphism analyses showed modest effects of M235T (angiotensinogen) and A-239T (angiotensin I-converting enzyme; P value range: 0.005 to 0.036), accounting for approximately 1% of the total variance of systolic BP at rest and during stress. Compared with this, the best multilocus models revealed multiple independent genetic modification effects (gene-gene, gene-gender, and gene-body mass index; P value range: 0.003 to 0.009), accounting for 2.5% and 7.3% of the total variance for systolic BP levels at rest and during stress, respectively. Our data support the hypothesis that multiple RAAS genetic modifications account for BP variation. We conclude that the RAAS genetic modifications may contribute more to the dynamic BP regulation in response to behavioral stress compared with the static BP value. In addition, we reported a gene-gene interaction between M235T (angiotensinogen) and A1159G (angiotensin I-converting enzyme) on stress systolic BP levels. We proposed a viable approach to test for the multiple genetic contributions to BP and hypertension.

Exercise and hypertension: recent advances in exercise prescription

Despite the pervasiveness of hypertension (HTN), the exercise dose needed to lower blood pressure (BP) remains to be quantified. The purpose of this manuscript is to discuss recent advances in exercise prescription (ExR x) for HTN. The take-home message in ExR x for those with HTN is that the antihypertensive effect is: immediate; elicited by low intensity, short-duration aerobic exercise; one of many health benefits; and individually tailored. With this message and the general rules of ExR x as a guide, those with HTN should exercise on most, preferably all, days of the week, with moderate intensity (40% to <60% of VO2 Reserve), for 30 minutes or more of continuous or accumulated physical activity per day, primarily of the endurance type, supplemented by resistance exercise. Additionally, those who are overweight should progress to a caloric energy expenditure of a minimum of 1000 kcal to more than 2000 kcal per week or more than 2.5 hours per week of moderate-intensity, aerobic exercise.