Isometric handgrip exercise and resting blood pressure: a meta-analysis of randomized controlled trials

Effects of the intensity, duration and muscle mass factors of isometric exercise on acute local muscle hemodynamic responses and systematic blood pressure regulation

Isometric exercise is a non-pharmacologic intervention to improve muscle hemodynamic responses and blood pressure in humans. However, the effects of intensity, duration, and muscle mass factors of isometric exercise on local muscle hemodynamic responses and systemic blood pressure regulation have not been studied. The purpose of this study was to assess whether various modes of isometric exercise could induce various levels of muscle hemodynamic responses that are related to the blood pressure changes. Near-infrared spectroscopy was used to assess muscle hemodynamic responses after 4 isometric exercise protocols in 20 healthy adults. One-way analysis of variance (ANOVA) with repeated measures was used to assess the effect of factors of isometric exercise on oxyhemoglobin, deoxy-hemoglobin, blood volume, and oxygenation. For oxygenation, the lowest mean was recorded for the unilateral isometric handgrip exercise at 30% of MVC for 2 min (-0.317 ± 0.379 μM) while the highest mean was observed for the isometric wall squat (1.496 ± 0.498 μM, P < 0.05). Additionally, both the bilateral isometric handgrip exercise at 30% MVC for 1 min (1.340 ± 0.711 μM, P < 0.05) and the unilateral isometric handgrip exercise at 20% MVC for 3 min (0.798 ± 0.324 μM, P < 0.05) are significantly higher than 30% of MVC for 2 min. Blood pressure showed an inverse trend with oxygenation changes of the forearm muscle. The study indicates that the duration and muscle mass of isometric exercise are more effective on oxygenation responses and systematic blood pressure regulation, and suggests that the local muscle oxygenation factor following isometric contractions may mediate systematic blood pressure regulation.

An Indian classical dance form, Kathak in maintaining handgrip strength symmetry and reducing the risk of hypertension

BACKGROUND

The present paper aimed to study handgrip strength (HGS) asymmetry and its association with hypertension in a sample of Kathak dancers and non-dancers of North India.

METHODS

Data on HGS and blood pressure were collected from 206 Kathak dancers and 235 age-matched controls, using standardized protocols. Pearson correlation coefficients assessed the association between HGS and hypertension, and binary logistic regression identified the risk of developing hypertension.

RESULTS

HGS asymmetry was higher among non-dancers. In Kathak dancers, systolic blood pressure (SBP) was positively correlated with HGS and negatively correlated with HGS asymmetry whereas diastolic blood pressure (DBP) was negatively correlated with both HGS and HGS asymmetry. Dancers with high HGS, have significantly reduced risk of developing hypertension. Non-dancers with HGS asymmetry were 1.8 times more likely to report hypertension, relative to dancers.

CONCLUSION

Kathak may be used as an alternative method for maintaining HGS symmetry and reducing the risk of developing hypertension.

Statistical heterogeneity in meta-analysis of hypertension and exercise training: A meta-review

We aim to evaluate the prevalence of reporting and the extent of statistical heterogeneity of systematic reviews with meta-analyses (SRMAs) of exercise training for hypertension and to provide practical recommendations for dealing with statistical heterogeneity. We systematically searched on four databases (from 2002 to September of 2023) for SRMAs comparing exercise interventions vs. a non-exercise control on blood pressure (BP) control in adults with hypertension. Fifty-nine SRMAs, with a median of 14 studies, were analysed. Cochran's Q (41%), I2 (24%), forest plots (44%), and particularly τ2 (54%) and prediction intervals (96.6%) frequently were not reported for the hypertension subgroup. The recalculated prediction intervals were discrepant (i.e., crossed the null effect) of significant 95% confidence intervals of most meta-analyses (systolic BP: 65%; diastolic BP: 92%). This suggests substantial heterogeneity across studies, which was often not acknowledged by authors' conclusions (78%). Consequently, downgrading the certainty of the available evidence may be justified alone due to heterogeneity across studies. Finally, we illustrate areas for improving I2 interpretation and provide practical recommendations on how to address statistical heterogeneity across all stages of a SRMA.

Exercise training and resting blood pressure: a large-scale pairwise and network meta-analysis of randomised controlled trials

OBJECTIVE

To perform a large-scale pairwise and network meta-analysis on the effects of all relevant exercise training modes on resting blood pressure to establish optimal antihypertensive exercise prescription practices.

DESIGN

Systematic review and network meta-analysis.

DATA SOURCES

PubMed (Medline), the Cochrane library and Web of Science were systematically searched.

ELIGIBILITY CRITERIA

Randomised controlled trials published between 1990 and February 2023. All relevant work reporting reductions in systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) following an exercise intervention of ≥2 weeks, with an eligible non-intervention control group, were included.

RESULTS

270 randomised controlled trials were ultimately included in the final analysis, with a pooled sample size of 15 827 participants. Pairwise analyses demonstrated significant reductions in resting SBP and DBP following aerobic exercise training (-4.49/-2.53 mm Hg, p<0.001), dynamic resistance training (-4.55/-3.04 mm Hg, p<0.001), combined training (-6.04/-2.54 mm Hg, p<0.001), high-intensity interval training (-4.08/-2.50 mm Hg, p<0.001) and isometric exercise training (-8.24/-4.00 mm Hg, p<0.001). As shown in the network meta-analysis, the rank order of effectiveness based on the surface under the cumulative ranking curve (SUCRA) values for SBP were isometric exercise training (SUCRA: 98.3%), combined training (75.7%), dynamic resistance training (46.1%), aerobic exercise training (40.5%) and high-intensity interval training (39.4%). Secondary network meta-analyses revealed isometric wall squat and running as the most effective submodes for reducing SBP (90.4%) and DBP (91.3%), respectively.

CONCLUSION

Various exercise training modes improve resting blood pressure, particularly isometric exercise. The results of this analysis should inform future exercise guideline recommendations for the prevention and treatment of arterial hypertension.

An evidence-based guide to the efficacy and safety of isometric resistance training in hypertension and clinical implications

More than 30 randomized controlled trials, supported by individual patient-level and group-level meta-analyses and a Delphi analysis of expert opinion, unequivocally show isometric resistance training (IRT) elicits antihypertensive benefits in healthy people and those with chronic illness. We aim to provide efficacy and safety evidence, and a guide for IRT prescription and delivery. Recommendations are made for the use of IRT in specific patient populations and appropriate methods for IRT delivery. Published data suggest IRT consistently elicits mean blood pressure reductions of 7.4/3.3 mmHg systolic blood pressure/diastolic blood pressure, equivalent to antihypertensive medication monotherapy. Blood pressure reductions of this size are associated with an approximate 13% to 22% reduction in major cardiovascular events. Moreover, IRT is safe in a range of patient populations. We suggest that IRT has the greatest potential benefit when used as an antihypertensive therapy in individuals unwilling and/or unable to complete aerobic exercise, or who have had limited adherence or success with it; individuals with resistant or uncontrolled hypertension, already taking at least two pharmacological antihypertensive agents; and healthy or clinical populations, as an adjunct to aerobic exercise and dietary intervention in those who have not yet attained control of their hypertension. IRT is efficacious and produces clinically meaningful blood pressure reductions (systolic blood pressure, 7 mmHg; diastolic blood pressure, 3 mmHg). IRT is safe and typical program delivery requires only about 17 min weekly. IRT should be used as an adjunct to other exercise modalities, in people unable to complete other types of exercise, or in resistant hypertension.

[Impact of isometric training on blood pressure: an umbrella study of systematic reviews and meta-analyses]

High blood pressure causes 45% of deaths from heart diseases and 51% of deaths from stroke.

OBJECTIVE

To conduct systematic search and summarize the systematic reviews and/or meta-analyses about impact of isometric training on blood pressure.

MATERIAL AND METHODS

Systematic search for publications in PubMed, Cochrane Library and Epistemonikos databases for the period from January of 2017 yr. to 19 of January 2023 yr. was carried out. The search was done by keywords: isometric exercises, isometric training, blood pressure, arterial hypertension, static resistance training, handgrip test. Methodological quality of included articles was assessed using the «Assessment of methodological quality of systematic reviews» (AMSTAR-2) tool. The number of systematic reviews equal 15 was analyzed.

RESULTS

The overall methodological quality of 15 included reviews, obtained by AMSTAR-2, revealed a very low confidence rate (critically low confidence, 10 publications) for results of systematic review and meta-analyses. In total, analysis and generalization of all results of included systematic reviews about blood pressure decrease by isometric training showed, that systolic blood pressure against the background of this method decreases on average by 6.1±2.0 mm Hg, and diastolic blood pressure - by 3.0±1.0 mm Hg.

CONCLUSION

Authors of 15 systemic reviews, included in an umbrella study, reached a common conclusion about isometric training efficacy in secondary prevention of arterial hypertension.

Exercise to Treat Hypertension: Late Breaking News on Exercise Prescriptions That FITT

ABSTRACT

Hypertension is the leading risk factor for cardiovascular disease and an independent predictor of mortality. The prevalence of hypertension has doubled in the last two decades and evidence suggests that almost half the individuals are unaware of their condition. The antihypertensive effects of exercise are now undisputable, and exercise training is recommended by the major professional and scientific societies, including the American College of Sports Medicine (ACSM), as first-line treatment to prevent, treat, and control hypertension. This review aims to overview the evidence supporting the current ACSM Frequency, Intensity, Time, and Type exercise recommendations for hypertension, discuss new and emerging evidence on exercise in the treatment of hypertension from our laboratories; and propose future directions of research integrating this new and emerging evidence.

Safety, efficacy and delivery of isometric resistance training as an adjunct therapy for blood pressure control: a modified Delphi study

Uncontrolled hypertension remains the major risk factor for cardiovascular disease. Isometric resistance training (IRT) has been shown to be a useful nonpharmacological therapy for reducing blood pressure (BP); however, some exercise physiologists and other health professionals are uncertain of the efficacy and safety of IRT. Experts' consensus was sought in light of the current variability of IRT use as an adjunct treatment for hypertension. An expert consensus-building analysis (Delphi study) was conducted on items relevant to the safety, efficacy and delivery of IRT. The study consisted of 3 phases: (1) identification of items and expert participants for inclusion; (2) a two-round modified Delphi exercise involving expert panelists to build consensus; and (3) a study team consensus meeting for a final item review. A list of 50 items was generated, and 42 international experts were invited to join the Delphi panel. Thirteen and 10 experts completed Delphi Rounds 1 and 2, respectively, reaching consensus on 26 items in Round 1 and 10 items in Round 2. The study team consensus meeting conducted a final item review and considered the remaining 14 items for the content list. A final list of 43 items regarding IRT reached expert consensus: 7/10 items on safety, 11/11 items on efficacy, 10/12 items on programming, 8/10 items on delivery, and 7/7 on the mechanism of action. This study highlights that while experts reached a consensus that IRT is efficacious as an antihypertensive therapy, some still have safety concerns, and there is also ongoing conjecture regarding optimal delivery.

The effectiveness and safety of isometric resistance training for adults with high blood pressure: a systematic review and meta-analysis

High blood pressure (BP) is a global health challenge. Isometric resistance training (IRT) has demonstrated antihypertensive effects, but safety data are not available, thereby limiting its recommendation for clinical use. We conducted a systematic review of randomized controlled trials comparing IRT to controls in adults with elevated BP (systolic ≥130 mmHg/diastolic ≥85 mmHg). This review provides an update to office BP estimations and is the first to investigate 24-h ambulatory BP, central BP, and safety. Data were analyzed using a random-effects meta-analysis. We assessed the risk of bias with the Cochrane risk of bias tool and the quality of evidence with GRADE. Twenty-four trials were included (n = 1143; age = 56 ± 9 years, 56% female). IRT resulted in clinically meaningful reductions in office systolic (-6.97 mmHg, 95% CI -8.77 to -5.18, p < 0.0001) and office diastolic BP (-3.86 mmHg, 95% CI -5.31 to -2.41, p < 0.0001). Novel findings included reductions in central systolic (-7.48 mmHg, 95% CI -14.89 to -0.07, p = 0.035), central diastolic (-3.75 mmHg, 95% CI -6.38 to -1.12, p = 0.005), and 24-h diastolic (-2.39 mmHg, 95% CI -4.28 to -0.40, p = 0.02) but not 24-h systolic BP (-2.77 mmHg, 95% CI -6.80 to 1.25, p = 0.18). These results are very low/low certainty with high heterogeneity. There was no significant increase in the risk of IRT, risk ratio (1.12, 95% CI 0.47 to 2.68, p = 0.8), or the risk difference (1.02, 95% CI 1.00 to 1.03, p = 0.13). This means that there is one adverse event per 38,444 bouts of IRT. IRT appears safe and may cause clinically relevant reductions in BP (office, central BP, and 24-h diastolic). High-quality trials are required to improve confidence in these findings. PROSPERO (CRD42020201888); OSF ( https://doi.org/10.17605/OSF.IO/H58BZ ).

Association between relative handgrip strength and hypertension in Chinese adults: An analysis of four successive national surveys with 712,442 individuals (2000-2014)

OBJECTIVES

This study aimed to identify the 15-year trends of handgrip strength-to-weight (relative HS) and assess the association between relative HS and hypertension among Chinese adults aged 20-69.

METHODS

Using a complex, stratified, multistage probability cluster sampling, we analyzed data collected from 712,442 adults aged 20-69 years in four successive national surveys (2000-2014). We used a handheld dynamometer to measure strength and divided by body weight to calculate the relative HS. Blood pressure was recorded with a sphygmomanometer and hypertension was defined as resting systolic blood pressure at least 140 mmHg or diastolic at least 90 mmHg. The Mann-Kendall trend test examined trends in relative HS over time. We also computed odd ratios (OR) and 95% confidence intervals (95% CI) by tertile of relative HS and examined the association between relative HS and hypertension.

RESULTS

The relative HS level decreased with the increase of age in both male and females (p trend <0.001). In each of four surveys, one interquartile decrease in relative HS was associated with an increased risk of hypertension by 44% (OR = 1.44, 95%CI: 1.40-1.47), 58% (OR = 1.58, 95%CI: 1.54-1.62), 48% (OR = 1.48, 95%CI: 1.45-1.52), 43% (OR = 1.43, 95%CI: 1.40-1.47), respectively.

CONCLUSION

In the Chinese adult population, the relative HS level decreased from 2000 to 2014 across all ages in both males and females. A lower relative HS was associated with a higher risk of hypertension. The findings provided evidence for the association between muscle strength and hypertension in large-scaled population.

Isometric handgrip exercise training reduces resting systolic blood pressure but does not interfere with diastolic blood pressure and heart rate variability in hypertensive subjects: a systematic review and meta-analysis of randomized clinical trials

To evaluate the effects of isometric handgrip exercise training (IHET) on blood pressure and heart rate variability in hypertensive subjects. Five databases were searched for randomized clinical trials in English, Spanish, or Portuguese evaluating the effect of IHET vs. no exercise on blood pressure (systolic and/or diastolic) and/or heart rate variability (low frequency [LF], high frequency [HF], and/or LF/HF ratio) through December 2020. Random-effects meta-analyses of mean differences (MDs) and/or standardized mean differences (SMDs) with 95% confidence intervals (CIs) were performed. Five trials were selected (n = 324 hypertensive subjects), whose durations ranged from 8 to 10 weeks. Compared to no exercise, IHET reduced systolic blood pressure (MD -8.11 mmHg, 95% CI -11.7 to -4.53, p < 0.001) but did not affect diastolic blood pressure (MD -2.75 mmHg, 95% CI -9.47-3.96, p = 0.42), LF (SMD -0.14, 95% CI -0.65-0.37, p = 0.59), HF (SMD 0.38, 95% CI -0.14-0.89, p = 0.15), or the LF/HF ratio (SMD -0.22, 95% CI -0.95-0.52, p = 0.57). IHET performed for 8-10 weeks had a positive effect on resting systolic blood pressure but did not interfere with diastolic blood pressure or heart rate variability in hypertensive subjects. These data should be interpreted with caution since all volunteers included in the studies were clinically medicated and their blood pressure was controlled.

Effects of isometric handgrip exercise with or without blood flow restriction on interference control and feelings

The purpose of this study was to investigate whether isometric handgrip exercise, with or without blood flow restriction, would alter interference control and feelings. 60 healthy young adults completed three experimental visits, consisting of four sets of 2 min isometric handgrip exercise, at 30% of maximal strength with or without blood flow restriction (50% of arterial occlusion pressure), or a non-exercise/time-matched control. Exercise-induced feeling inventory and Stroop Color Word Test were performed at pre- and ~10-min post-exercise, respectively. Bayes factors (BF₁₀ ) quantified the evidence for or against the null. There were no changes or differences between conditions for interference control following exercise with or without blood flow restriction (Incongruent BF₁₀ : 0.155; Stroop Interference BF₁₀ : 0.082). There were also no differences in the error rate as well as no differences between conditions for changes in 'positivity' or 'revitalization'. Feelings of 'tranquility' were reduced relative to a control following exercise with (median δ [95% credible interval]: -0.74 (-1.05, -0.45), BF₁₀ : 5515.7) and without (median δ: -0.72 [-1.02, -0.41], BF₁₀ : 571.3) blood flow restriction. These changes were not different between exercise conditions. Feelings of 'physical exhaustion' were increased relative to a control following exercise without blood flow restriction (median δ: 0.35[0.09, 0.61], BF₁₀ : 5.84). However, this increase was not different from the same exercise with blood flow restriction. These results suggest that 1) isometric handgrip exercise could be performed without impairing interference control, even when blood flow restriction is added, and that 2) changes in feelings occur independent of changes in interference control.

Isometric exercise and inter-individual response differences on resting systolic and diastolic blood pressure in adults: a meta-analysis of randomized controlled trials

PURPOSE

Isometric exercise (IE) has been shown to reduce resting systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults. However, no one to date has determined whether true inter-individual response differences (IIRD) versus random variability exist with respect to IE and resting SBP and DBP in adults ≥18 years of age. The purpose of the current study was to address this gap.

METHODS AND MATERIALS

Using the meta-analytic approach, randomised controlled trials from a recent meta-analysis that examined the effects of IE on resting SBP and DBP were included. Change outcome standard deviations for SBP and DBP from IE and control groups were used to calculate true IIRD from each study. The inverse variance heterogeneity (IVhet) model was used to pool results.

RESULTS

Pooled changes for true IIRD in SBP (16 studies, 411 participants) were 3.3 mmHg (95% confidence interval, -3.1 to 5.6 mmHg) while tau (τ) was 4.2. For DBP, true IIRD (16 studies, 411 participants) were 2.3 mmHg (95% confidence interval, -0.7 to 3.3 mmHg) while tau (τ) was 2.2. The 95% prediction interval for true IIRD in a future study was -5.8 to 7.4 mmHg for SBP and -2.7 to 4.2 mmHg for DBP. The percent chance, i.e. probability, of a clinically meaningful difference of 2 mmHg was 68% for SBP and 75% for DBP, both of which were only considered as 'possibly clinically important'.

CONCLUSION

While IE reduces resting SBP and DBP in adults, the results of the current study suggest that random variability versus true IIRD account for any potential differences as a result of IE on changes in resting SBP and DBP in adults. Thus, a search for potential moderators and mediators, including potential genetic interactions associated with IE, may not be warranted.

Effect of intermittent isometric handgrip exercise protocol with short exercise duration on cognitive performance

The handgrip exercise, a small muscle exercise, is useful for exercise therapy, particularly in the elderly and bedridden patients. The isometric handgrip (IHG) exercise has been utilized in training programs to reduce resting blood pressure; however, the acute effects of the IHG exercise on cognitive performance are not fully understood. The present study aimed to investigate the effect of an intermittent IHG exercise protocol with short exercise duration, which minimizes the arterial blood pressure response to exercise, on cognitive performance. Twenty-two young healthy subjects performed the intermittent IHG exercise protocol, which consisted of 30-s IHG and 45-s recovery × 16 trials; the exercise intensity of the IHG exercise was 30% of the maximal voluntary contraction. Cognitive performance was evaluated before and after the exercise with the Go/No-Go and memory recognition tasks. Specifically, the reaction time (RT) and performance accuracy were measured. The intermittent IHG exercise protocol did not change the RT or performance accuracy of either the Go/No-Go task (P = 0.222 and P = 0.260, respectively) or the memory recognition task (P = 0.427 and P = 0.245, respectively). These findings suggest that the intermittent IHG exercise protocol with short exercise duration may not provide enough stimulation to improve cognitive performance despite being useful as a safe exercise therapy in the elderly and in patients with cardiovascular disease.

Personalized exercise prescription in the prevention and treatment of arterial hypertension: a Consensus Document from the European Association of Preventive Cardiology (EAPC) and the ESC Council on Hypertension

Treatment of hypertension and its complications remains a major ongoing health care challenge. Around 25% of heart attacks in Europe are already attributed to hypertension and by 2025 up to 60% of the population will have hypertension. Physical inactivity has contributed to the rising prevalence of hypertension, but patients who exercise or engage in physical activity reduce their risk of stroke, myocardial infarction, and cardiovascular mortality. Hence, current international guidelines on cardiovascular disease prevention provide generic advice to increase aerobic activity, but physiological responses differ with blood pressure (BP) level, and greater reductions in BP across a population may be achievable with more personalized advice. We performed a systematic review of meta-analyses to determine whether there was sufficient evidence for a scientific Consensus Document reporting how exercise prescription could be personalized for BP control. The document discusses the findings of 34 meta-analyses on BP-lowering effects of aerobic endurance training, dynamic resistance training as well as isometric resistance training in patients with hypertension, high-normal, and individuals with normal BP. As a main finding, there was sufficient evidence from the meta-review, based on the estimated range of exercise-induced BP reduction, the number of randomized controlled trials, and the quality score, to propose that type of exercise can be prescribed according to initial BP level, although considerable research gaps remain. Therefore, this evidence-based Consensus Document proposes further work to encourage and develop more frequent use of personalized exercise prescription to optimize lifestyle interventions for the prevention and treatment of hypertension.

[Sport and exercise in prevention and therapy of cardiovascular diseases]

Sport and exercise improve physical performance, quality of life and prognosis in virtually all cardiovascular risk factors and diseases. Not only moderate endurance exercise but also specific strength training programs are recommended. However, research and practice are also focusing on more intense, interval exercise and targeted interventions to improve performance. In the primary and secondary prevention of cardiovascular diseases, adapted strength training without press breathing is also suitable.In addition to moderate endurance training, higher-intensity, interval-type exercise is now recommended for individual patients. An individually adapted load control is important after exhaustion in the load ECG. Rules of thumb should not be applied. With the exception of nicotine cessation, an improvement in physical performance is the most effective measure in terms of prognosis. Increased daily activity measured by a daily step count of more than 7500, optimally more than 10 000, also has a positive effect.

The Relative Handgrip Strength and Risk of Cardiometabolic Disorders: A Prospective Study

Background

This study aims to investigate the association between handgrip strength (HGS) and cardiometabolic disorders (CMD), including hypertension, diabetes, and dyslipidemia, in a prospective study.

Methods

The association between HGS and CMD was examined using the data from 5,271 Chinese adult participants ≥45 years old enrolled in the CHARLS (Chinese Health and Retirement Prospective Cohort Study) during 2011-2015. Relative HGS, calculated as maximal absolute HGS from both hands divided by body mass index, was used in the primary analysis and divided into three groups according to the tertiles (T1, T2, and T3).

Results

The participants with higher relative HGS had a lower risk of hypertension, diabetes, and dyslipidemia than those with lower HGS, although did not reach statistical significance for diabetes and hypertension in males. Participants with higher HGS had significantly lower risk of hypertension [T3 vs. T1: OR = 0.69, 95% CI = 0.51-0.91, P = 0.010] and dyslipidemia (OR = 0.65, 95% CI = 0.51-0.83, P < 0.001) in males. For females, participants with higher HGS had significantly lower risks of dyslipidemia (OR = 0.67, 95% CI = 0.54-0.83, P < 0.001).

Conclusion

A consistent association was observed between higher relative HGS and lower risk of CMD. Further research is required to evaluate whether relative HGS can be a convincing predictor for the occurrence of CMD and as a target for intervention in the high-risk population.

Are Blood Pressure and Cardiovascular Stress Greater in Isometric or in Dynamic Resistance Exercise?

Medical and sports medicine associations are reluctant to endorse isometric exercise to the same extent as dynamic resistance exercise (RE). The major concern is the fear of greater increases in blood pressure (BP) that might be associated with isometric exercise. This review comprehensively presents all human studies that directly compared the magnitude of hemodynamic responses between isometric and dynamic RE. We also discuss possible mechanisms controlling BP-response and cardiovascular adjustments during both types of RE. The most prominent finding was that isometric and dynamic RE using small-muscle mass evoke equal increases in BP; however, the circulatory adjustments contributing to this response are different in dynamic and isometric RE. In contrast, studies using large-muscle mass report inconsistent results for the magnitude of BP-response between the two types of RE. Thus, when the same muscles and workloads are used, the increase in BP during isometric and dynamic RE is more comparable to what is commonly believed. However, it should be noted that only a few studies equalized the workload in two types of RE, most used small sample sizes, and all studies employed healthy participants. More studies are needed to compare the cardiovascular risks associated with isometric and dynamic RE, especially in individuals with chronic disease.

Exercise and Hypertension

Hypertension is a fatal yet preventable risk factor for cardiovascular disease and is responsible for majority of cardiovascular mortality. Hypertension is closely associated with inactive lifestyle. Physical activity and/or exercise are shown to delay development of hypertension. Both aerobic and resistance exercise have been proven to reduce blood pressure (BP) effectively. Since brisk walking is an easy, inexpensive, simple, and effective way of exercise, this type of an aerobic workout can be recommended to society. All professional organizations and government bodies recommend moderate-intensity aerobic exercise for at least 30 min on at least 3 days of the week or resistance exercise on 2-3 days of the week. Exercise sessions can either be continuous for 30 min or be composed of at least 10 min of short exercise duration to a daily total of 30 min. After an exercise session, BP decreases, and this decline continues for up to 24 h; which is called post-exercise hypotension. Overall 5 mmHg decrease in BP with regular exercise may be ensured. With a decrease of 5 mmHg in systolic BP, mortality due to coronary heart disease decreases by 9%, mortality due to stroke decreases by 14% and all-cause mortality decreases by 7%. Regular exercise should therefore be recommended for all individuals including normotensives, prehypertensives, and hypertensives.

Nonpharmacological interventions for the prevention of hypertension in low- and middle-income countries: a systematic review and meta-analysis

Hypertension is the single biggest cause of various cardiovascular complications and at the same time one of the most preventable phenomena. Low- and middle-income countries (LMICs) are facing increasing prevalence of hypertension which is imposing a huge burden on morbidity, premature mortality, and catastrophic health expenditure. This systematic review searched for the nonpharmacological interventions for prevention of hypertension among normotensive people in LMICs considering the period 1990–2016. This review has been conducted following standard methodology of Cochrane review involving two independent reviewers in screening, quality appraisal, and data extraction. Narrative synthesis of included articles was demonstrated using tables and meta-analysis was conducted to pool the estimates of studies which fulfilled the criteria. Total seven trials were included in the review with 6046 participants from eight LMICs. Two cluster randomized trials were pooled and there was a statistically significant effect (Systolic Blood Pressure: mean difference −2.35 [95% CI: −4.31 to −0.38], Diastolic Blood Pressure: mean difference −2.11 [95% CI: −3.20 to −1.02]) of home based health education in reducing blood pressure. Three individual studies reported reduction of blood pressure as a result of restricted dietary sodium intake. None of the studies was appraised as low risk of bias due to poor methodological quality. Non-pharmacological interventions can play important role in preventing the development of hypertension among normotensive people. Further trials with longer follow-up period and robust methods are recommended for getting stronger evidence on these interventions.

Home-based isometric handgrip training on RBP in hypertensive adults-Partial preliminary findings from RCT

OBJECTIVE

The aim of this study is to confirm whether 8 weeks of home-based isometric handgrip (IHG) training would reduce resting blood pressure (RBP) in an adult Indian population.

METHODOLOGY

Hypertensive patients (Stage 1 [previously prehypertension] and Stage 2 [previously Stage 1 hypertension]) aged 30-45 years, male and female, were included.

INTERVENTION

Two groups were included (active control group and IHG training group at 30% of maximal voluntary isometric contraction). Outcomes of this study were resting pulse rate (PR) and RBP, which were taken at baseline and after 8 weeks. Stratified randomization was done by sex and hypertension grade. The study was a double-blind intervention (both participants and the assessor were blinded to intervention allotment).

RESULTS

Forty hypertensive individuals were randomly assigned to a control (N = 20) and an 8-week home-based IHG training (N = 20) using a stratified random sampling technique. Each training session consisted of 4 × 2 min bouts with a 4-min rest between bouts for 8 weeks. Resting PR and RBP were taken at baseline and after 8 weeks. After 8 weeks, there was a significant reduction in blood pressure and PR values in the IHG group as compared with those in the control group: systolic blood pressure (mean difference, MD -8.75 mmHg; 95% CI [-6.51, -10.39]); diastolic blood pressure (MD -8.35 mmHg; 95% CI [-6.25, -10.45]); mean arterial pressure (MD -8.13 mmHg; 95% CI [-6.21, -10.05]); and PR (MD -8.90 mmHg; 95% CI [-5.08, -12.72].

CONCLUSION

On the basis of study findings, home-based IHG training can be used as an adjunct to control BP in the initial stage of hypertension in an Indian population.

Association of handgrip strength with the prevalence of hypertension in a Chinese Han population

Objective

Handgrip strength (HGS) exercise has been reported to reduce blood pressure in both hypertensive and normotensive patients. In this study, we evaluated the association of HGS with hypertension in a Chinese Han Population.

Methods

A total of 11,151 subjects mainly consisting of a rural population were recruited with a multi-stage sampling method in Jurong city, Jiangsu Province, China. Besides hypertension and diabetes, major chronic diseases were excluded. HGS was categorized into tertiles by age and gender. Logistic regression was used to estimate the association of HGS and hypertension with the odds ratio (OR) and 95% confidence interval (CI).

Results

From low to high tertiles of HGS, diastolic blood pressure (DBP) was significantly increased (74.52 ± 7.39, 74.70 ± 7.03, and 75.54 ± 7.01 mmHg, respectively; P_trend = 0.001), as well as in females (P_trend=0.003). The differences in DBP among the tertiles of HGS were still significant in females even after adjusting for covariates (P_trend=0.048). No significant differences in systolic blood pressure (SBP) were observed among the tertiles of HGS (P>0.05). Compared to low HGS, high HGS was significantly associated with hypertension after adjustment for age and gender (adjusted OR, 1.19; 95% CI, 1.06–1.34; P =0.004). A stratified analysis showed that the significant association of high HGS and hypertension was also observed with the following factors even after adjusting for age and gender: female gender (adjusted OR, 1.25; 95% CI, 1.08–1.46; P=0.004), ages of 60–69 years (adjusted OR, 1.29; 95% CI, 1.06–1.57; P=0.011), and married (adjusted OR, 1.20; 95% CI, 1.06–1.37; P=0.005). However, no significant associations were found after adjusting for age, gender, smoking status, drinking status, body mass index, physical activity level, glucose, high- and low-density lipoprotein cholesterol, total cholesterol, and triglyceride (P>0.05).

Conclusion

The findings of the current study suggest that HGS was positively correlated with DBP in a rural population, and high HGS was associated with hypertension in females; however, the association may be modified by smoking status, drinking status, body mass index, physical activity, cholesterol level, and glucose level. Further utilization of HGS exercises to intervene in the development and prognosis of hypertension should be verified in the future.

Resting blood pressure reductions following handgrip exercise training and the impact of age and sex: a systematic review and narrative synthesis

BACKGROUND

The risk of developing cardiovascular disease can be directly correlated to one's resting blood pressure (BP), age, and biological sex. Resting BP may be successfully reduced using handgrip exercise training, although the impact of age and sex on training effectiveness has yet to be systematically evaluated. The objective of this systematic review is to determine this impact of age and sex on handgrip-induced changes to resting BP.

METHODS

Data sources included MEDLINE, Embase, Cochrane Reviews, CINAHL, SPORTDiscus, Web of Science, AMED, PubMed, and Scopus through May 2018. Eligibility criteria were those with prospective handgrip exercise training of ≥ 4 weeks with reported impact on resting systolic BP (SBP). Screening of articles, data extraction, and quality appraisal were completed in duplicate. When necessary, the corresponding authors were contacted to provide segregated data based on age (younger, 18-54 years; aged, > 55 years) and sex (men, women) categories. SBP was primarily explored with numerous secondary outcomes of interest summarized as a narrative synthesis.

RESULTS

After screening 1789 articles, 26 full texts were reviewed. Eight studies reported data in a way that facilitated age and sex comparisons of primary outcomes, while 7 of 18 studies reporting pooled data (men and women) provided segregated results. Research spans 1992-2018 and represents 466 participants; at least 43.1% of whom are women. Although weighted mean differences reveal that handgrip training-induced SBP reductions are similar when merely comparing sexes (women; - 5.6 mmHg, men; - 4.4 mmHg) or ages (younger; - 5.7 mmHg, aged; - 4.4 mmHg), when the impact of sex and age is simultaneously evaluated, aged women experience the largest reduction in SBP (- 6.5 mmHg). Many factors were explored for their impact on resting BP reductions and have been summarized in the corresponding narrative synthesis.

CONCLUSIONS

Handgrip exercise is an effective modality for resting BP reduction resulting in clinically significant reductions for men and women of all ages.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015019792.

Handgrip strength is positively related to blood pressure and hypertension risk: results from the National Health and nutrition examination survey

Background

Isometric handgrip resistance exercise, a nonpharmacological lifestyle modification, has been recommended as a first-line treatment for hypertension. This study aimed to examine the relationship of handgrip strength to blood pressure and the risk of hypertension.

Methods

The responses and examination of 4597 participants in the National Health and Nutrition Examination Survey (NHANES) were analyzed in this study. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were transformed to age- and sex-specific z-scores. Handgrip strength was adjusted by weight (kg) and converted to an age- and sex-specific z-score. The relationships of SBP and DBP to handgrip strength were analyzed by Pearson correlation test and multivariable linear regression. Binary logistic regression was used to analyze the association between handgrip strength and prevalence of hypertension.

Results

Handgrip strength was positively related to higher DBP in men and women. In men, logistic regression models revealed that increased handgrip strength was associated with higher risk of hypertension after adjusting for age, BMI, smoking and drinking status; OR was 1.24 (95%CI: 1.04–1.48). After stratifying on BMI, handgrip strength was significantly associated with higher risk of hypertensions after adjusting for age, BMI, smoking and drinking status in overweight and obese men; OR was 1.31 (95%CI: 1.05–1.63). No significant associations were observed in women.

Conclusions

Increased handgrip strength is associated with higher DBP in men and women. In men, especially overweight and obese men, strong handgrip strength may be associated with higher risk of hypertension.

Electronic supplementary material

The online version of this article (10.1186/s12944-018-0734-4) contains supplementary material, which is available to authorized users.

Twenty weeks of isometric handgrip home training to lower blood pressure in hypertensive older adults: a study protocol for a randomized controlled trial

BACKGROUND

Hypertension markedly increases the risk of cardiovascular diseases and overall mortality. Lifestyle modifications, such as increased levels of physical activity, are recommended as the first line of anti-hypertensive treatment. A recent systematic review showed that isometric handgrip (IHG) training was superior to traditional endurance and strength training in lowering resting systolic blood pressure (SBP). The average length of previous IHG training studies is approximately 7.5 weeks with the longest being 10 weeks. Therefore, presently it is unknown if it is possible to further lower blood pressure levels beyond the 10-week mark. Recently, we developed a novel method for monitoring handgrip intensity using a standard Nintendo Wii Board (Wii). The primary aim of this study is to explore the effects of a 20-week IHG home training facilitated by a Wii in hypertensive older adults (50 + years of age) on lowering SBP compared to usual care. Secondary aims are to explore if/when a leveling-off effect on SBP will occur during the 20-week intervention period in the training group and to explore adherence and potential harms related to the IHG home training.

METHODS/DESIGN

Based on previous evidence, we calculated that 50 hypertensive (SBP between 140 and 179 mmHg), older adults (50 + years of age) are needed to achieve a power of 80% or more. Participants will be randomly assigned to either an intervention >group (IHG home training + hypertension guidelines on lifestyle changes) or to a control group (hypertension guidelines on lifestyle changes). Participants in the intervention group will perform IHG home training (30% of maximum grip strength for a total of 8 min per day per hand) three times a week for 20 weeks. Resting blood pressure and maximal handgrip strength will be obtained by a blinded outcome assessor in both groups at specific time points (baseline, follow-up at 5, 10, 15, and 20 weeks) throughout the study.

DISCUSSION

This assessor-blinded, randomized controlled trial will explore the effect of a 20-week IHG home training intervention on resting blood pressure in hypertensive older adults. In addition, the trial will report adherence and potential harms related to the IHG home training.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT03069443 . Registered on 3 March 2017.

The antihypertensive effects of aerobic versus isometric handgrip resistance exercise

BACKGROUND

Aerobic exercise reduces blood pressure (BP) on average 5-7 mmHg among those with hypertension; limited evidence suggests similar or even greater BP benefits may result from isometric handgrip (IHG) resistance exercise.

METHOD

We conducted a randomized controlled trial investigating the antihypertensive effects of an acute bout of aerobic compared with IHG exercise in the same individuals. Middle-aged adults (n = 27) with prehypertension and obesity randomly completed three experiments: aerobic (60% peak oxygen uptake, 30 min); IHG (30% maximum voluntary contraction, 4 × 2 min bilateral); and nonexercise control. Study participants were assessed for carotid-femoral pulse wave velocity pre and post exercise, and left the laboratory wearing an ambulatory BP monitor.

RESULTS

SBP and DBP were lower after aerobic versus IHG (4.8 ± 1.8/3.1 ± 1.3 mmHg, P = 0.01/0.04) and control (5.6 ± 1.8/3.6 ± 1.3 mmHg, P = 0.02/0.04) over the awake hours, with no difference between IHG versus control (P = 0.80/0.83). Pulse wave velocity changes following acute exercise did not differ by modality (aerobic increased 0.01 ± 0.21 ms, IHG decreased 0.06 ± 0.15 ms, control increased 0.25 ± 0.17 ms, P > 0.05). A subset of participants then completed either 8 weeks of aerobic or IHG training. Awake SBP was lower after versus before aerobic training (7.6 ± 3.1 mmHg, P = 0.02), whereas sleep DBP was higher after IHG training (7.7 ± 2.3 mmHg, P = 0.02).

CONCLUSION

Our findings did not support IHG as antihypertensive therapy but that aerobic exercise should continue to be recommended as the primary exercise modality for its immediate and sustained BP benefits.

Effect of traditional resistance training on blood pressure in normotensive elderly persons: a systematic review of randomized controlled trials and meta-analyses

Abstract The objective of the present study was to determine the effectiveness of the regular practice of traditional resistance training (RT) on systolic (SBP) and diastolic blood pressure (DBP) in normotensive elderly persons. A systematic review of randomized clinical trials and meta-analyses was performed. Searches were performed without language restrictions in different databases. Randomized clinical trials published from 1966 to 2010 that assessed the effects of traditional RT on resting blood pressure (BP) and/or for the treatment of high BP were included. Only studies that assessed the effects of traditional RT on elderly adults, regardless of the number of exercises, with the presence of a control group and comparisons between groups, were included. Twenty-nine studies were found, but only six met the inclusion criteria. The mean difference was used for meta-analysis, using a 95% confidence interval and a random effect model. Traditional RT induced a significant decrease in SBP (-6.63 mmHg; p=0.02) but not in DBP (-3.34 mmHg; p=0.11). These results suggest that traditional RT may be a non-pharmacological strategy for the control of BP in the elderly.

Acute and Chronic Effects of Isometric Handgrip Exercise on Cardiovascular Variables in Hypertensive Patients: A Systematic Review

The aim of this study was to describe, through a systematic review, the acute and chronic effects of isometric handgrip exercise on cardiovascular variables in hypertensive individuals. In this systematic review, we included studies that analyzed whether a single bout or a program with isometric exercises affect cardiovascular variables in hypertensive adults. The electronic database PubMed/Medline was searched for relevant studies published until May 2017. Of the 2927 studies initially identified, 2916 were excluded based on title and abstract and five on the basis of full-text assessment, leaving six studies remaining. In addition, one further study cited in the references of the included articles was included in this review, totaling seven studies included (five studies on the chronic effects of isometric handgrip exercise on cardiovascular parameters). None of the acute studies observed post-exercise hypotension. The majority of the chronic studies found decreases in office blood pressure after isometric handgrip training, with training ranging from 6 to 10 weeks, while heart rate variability parameters were improved in one study and did not change in another. Reduction in oxidative stress was observed; however, this variable was only analyzed in one study. In hypertensives, acute responses to isometric handgrip exercise are very limited due to the small number of studies, therefore more research is required. Furthermore, chronic isometric handgrip training reduces blood pressure; however, there is still a gap in the knowledge on the effects of this modality of exercise on other cardiovascular variables—such as endothelial function, oxidative stress, and cardiac autonomic modulation—which should be addressed in future studies.

Development of a recumbent isometric yoga program for patients with severe chronic fatigue syndrome/myalgic encephalomyelitis: A pilot study to assess feasibility and efficacy

Background

Our previous randomized controlled trial demonstrated that isometric yoga in a sitting position reduces fatigue in patients with chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). However, some patients experience difficulties sitting or practicing isometric yoga in a sitting position for long periods. To date, therapeutic interventions for patients with severe symptoms have not been established. Therefore, we developed a recumbent isometric yoga program, which takes approximately 20 min to complete, designed to reduce fatigue in patients with severe CFS/ME. The aim of this pilot study was to assess the feasibility, safety, and usefulness of this program.

Methods

This pilot study included 12 adult patients with CFS/ME. Six patients were reluctant to practice isometric yoga in a sitting position because of the severity of their fatigue (group 1). The remaining six patients had previously practiced isometric yoga in a sitting position (group 2). For 3 months, the patients of both groups practiced recumbent isometric yoga every 2 to 4 weeks with a yoga instructor and at home on other days if they could. The short-term effects of isometric yoga on fatigue were assessed using the Profile of Mood Status (POMS) questionnaire immediately before and after their final session with the yoga instructor. The long-term effects of isometric yoga on fatigue were assessed using the Chalder Fatigue Scale (FS) questionnaire before and after the intervention period. Adverse events, satisfaction with the program, and preference of yoga position (sitting or recumbent) were also recorded.

Results

All subjects completed the intervention. In both groups, the POMS fatigue score was significantly decreased after practicing the 20-min yoga program and the Chalder FS score was decreased significantly after the 3-month intervention period. There were no serious adverse events. All subjects in group 2 preferred the recumbent isometric yoga program over a sitting yoga program.

Conclusions

This study suggests that recumbent isometric yoga is a feasible and acceptable treatment for patients with CFS/ME, even for patients who experience difficulty practicing isometric yoga in the sitting position.

The efficacy of isometric resistance training utilizing handgrip exercise for blood pressure management: A randomized trial

INTRODUCTION

Hypertension is a major risk factor contributing to cardiovascular disease, which is the number one cause of deaths worldwide. Although antihypertensive medications are effective at controlling blood pressure, current first-line treatment for hypertension is nonpharmacological lifestyle modifications. Recent studies indicate that isometric resistance training (IRT) may also be effective for assisting with blood pressure management. The aim of this study was to determine the efficacy of IRT for blood pressure management and the suitability of a low-intensity working control group.

METHODS

Forty hypertensive individuals, aged between 36 and 65 years, conducted IRT for 8 weeks. Participants were randomized into 2 groups, working at an intensity of either 5% or 30% of their maximum voluntary contraction. Participants performed 4 × 2 minute isometric handgrip exercises with their nondominant hand, each separated by a 3-minute rest period, 3 days a week.

RESULTS

Blood pressure measurements were conducted at baseline and at the end of the protocol using a Finometer. Eight weeks of isometric resistance training resulted in a 7-mmHg reduction of resting systolic blood pressure (SBP) (136 ± 12 to 129 ± 15; P = 0.04) in the 30% group. Reductions of 4 mmHg were also seen in mean arterial pressure (MAP) (100 ± 8 to 96 ± 11; P = 0.04) in the 30% group. There were no statistically significant reductions in diastolic blood pressure for the 30% group, or any of the data for the 5% group.

CONCLUSION

Isometric resistance training conducted using handgrip exercise at 30% of maximum voluntary contraction significantly reduced SBP and MAP. A lack of reduction in blood pressure in the 5% group indicates that a low-intensity group may be suitable as a working control for future studies.

Whole-body strength training with Huber Motion Lab and traditional strength training in cardiac rehabilitation: A randomized controlled study

BACKGROUND

Isometric strengthening has been rarely studied in patients with coronary heart disease (CHD), mainly because of possible potential side effects and lack of appropriate and reliable devices.

OBJECTIVE

We aimed to compare 2 different modes of resistance training, an isometric mode with the Huber Motion Lab (HML) and traditional strength training (TST), in CHD patients undergoing a cardiac rehabilitation program.

DESIGN

We randomly assigned 50 patients to HML or TST. Patients underwent complete blinded evaluation before and after the rehabilitation program, including testing for cardiopulmonary exercise, maximal isometric voluntary contraction, endothelial function and body composition.

RESULTS

After 4 weeks of training (16 sessions), the groups did not differ in body composition, anthropometric characteristics, or endothelial function. With HML, peak power output (P=0.035), maximal heart rate (P<0.01) and gain of force measured in the chest press position (P<0.02) were greater after versus before training.

CONCLUSION

Both protocols appeared to be well tolerated, safe and feasible for these CHD patients. A training protocol involving 6s phases of isometric contractions with 10s of passive recovery on an HML device could be safely implemented in rehabilitation programs for patients with CHD and improve functional outcomes.

Exercise as medicine - evidence for prescribing exercise as therapy in 26 different chronic diseases

This review provides the reader with the up-to-date evidence-based basis for prescribing exercise as medicine in the treatment of 26 different diseases: psychiatric diseases (depression, anxiety, stress, schizophrenia); neurological diseases (dementia, Parkinson's disease, multiple sclerosis); metabolic diseases (obesity, hyperlipidemia, metabolic syndrome, polycystic ovarian syndrome, type 2 diabetes, type 1 diabetes); cardiovascular diseases (hypertension, coronary heart disease, heart failure, cerebral apoplexy, and claudication intermittent); pulmonary diseases (chronic obstructive pulmonary disease, asthma, cystic fibrosis); musculo-skeletal disorders (osteoarthritis, osteoporosis, back pain, rheumatoid arthritis); and cancer. The effect of exercise therapy on disease pathogenesis and symptoms are given and the possible mechanisms of action are discussed. We have interpreted the scientific literature and for each disease, we provide the reader with our best advice regarding the optimal type and dose for prescription of exercise.

Resting blood pressure reductions following isometric handgrip exercise training and the impact of age and sex: protocol for a systematic review

BACKGROUND

The risk of developing cardiovascular disease is directly correlated to one's resting blood pressure (BP), age, and biological sex. Resting BP can be reduced using handgrip exercise training, but the impact of age and sex on the effectiveness of training is not well documented.

METHODS/DESIGN

A systematic search of the literature will be conducted for all experimental studies (including randomized controlled trials and prospective experiments) that report the influence of isometric handgrip exercise training on resting systolic blood pressure. The databases Medline, Embase, Cochrane Reviews, Cumulative Index to Nursing and Allied Health Literature (CINAHL), SPORTDiscus, Web of Science, Allied and Complementary Medicine (AMED), PubMed, and Scopus will be searched until 1 December 2015. Screening of potential articles, data abstraction, and quality appraisal will be completed in duplicate independently. When necessary, corresponding authors will be contacted in order to facilitate the separation of pooled data into age and sex categories. Methodological quality will be determined using the Quality Assessment Framework developed by the Cochrane Collaboration and the Newcastle-Ottawa Quality Assessment Scale as appropriate. Any discrepancies will be resolved by a third author. Findings will be presented in accordance with the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines.

DISCUSSION

This systematic review will determine the overall effectiveness of handgrip exercise training in improving resting blood pressure. A novel, focused assessment will contrast effectiveness of handgrip training based on the age (younger 18-54 years, older >55 years) and the sex (men, women) of study participants. This information is essential to consolidate before moving forward with the development and implementation of handgrip exercise training programmes which are designed to best meet the needs of particular cohorts.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015019792.

Isometric exercise training for blood pressure management: a systematic review and meta-analysis to optimize benefit

The objective of our study was to examine the effects of isometric resistance training (IRT) on resting blood pressure in adults. We conducted a systematic review and meta-analysis of randomized-controlled trials lasting ⩾2 weeks, investigating the effects of isometric exercise on blood pressure in healthy adults (aged ⩾18 years), published in a peer-reviewed journal between 1 January 1966 to 31 January 2015. We included 11 randomized trials, totaling 302 participants. The following reductions were observed after isometric exercise training; systolic blood pressure (SBP) mean difference (MD) -5.20 mm Hg (95% confidence interval (CI) -6.08 to -4.33, P<0.00001); diastolic blood pressure (DBP) MD -3.91 mm Hg (95% CI -5.68 to -2.14, P<0.0001); and mean arterial blood pressure (MAP) MD -3.33 mm Hg (95% CI -4.01 to -2.66, P<0.00001). Sub-analyses showed males tended to reduce MAP MD -4.13 mm Hg (95% CI -5.08 to -3.18) more than females. Subjects aged ⩾45 years demonstrated larger reductions in MAP MD -5.51 mm Hg (95% CI -6.95 to -4.06) than those <45 years. Subjects undertaking ⩾8 weeks of IRT demonstrated a larger reduction in SBP MD -7.26 mm Hg (95% CI -8.47 to -6.04) and MAP MD -4.22 mm Hg (95% CI -5.08 to -3.37) than those undertaking<8 weeks. Hypertensive participants in IRT demonstrated a larger reduction in MAP MD -5.91 mm Hg (95% CI -7.94 to -3.87) than normotensive participants MD -3.01 mm Hg (95% CI -3.73 to -2.29). Our study indicated that IRT lowers SBP, DBP and MAP. The magnitude of effect may be larger in hypertensive males aged ⩾45 years, using unilateral arm IRT for >8 weeks.

Effects of handgrip exercise or inorganic nitrate supplementation on 24-h ambulatory blood pressure and peripheral arterial function in overweight and obese middle age and older adults: A pilot RCT

INTRODUCTION

Hypertension is a major contributor to the global burden of cardiovascular diseases and its prevalence increases progressively with ageing. Therefore the identification of effective, age-friendly exercise and nutritional interventions which lower blood pressure (BP) is a research priority.

OBJECTIVE

To undertake a pilot RCT examining the efficacy of isometric handgrip exercise (IHGE) and beetroot juice (a rich source of inorganic nitrate) consumption in modifying clinic and 24-h ambulatory BP (24-h ABP), peripheral arterial function and plasma asymmetric dimethylarginine (ADMA) in older overweight and obese adults.

DESIGN

Thirty middle age and older adults (62±5 years) were randomised to: (a) bilateral IHGE at 50% of maximal voluntary contraction (8 min/day), (b) 140 ml/day of concentrated beetroot juice, or (c) no-intervention (control group), for 7 days. All groups followed a standardised diet to control nitrate intake. Clinic and 24-h ABP, peripheral arterial function quantified by pulse wave velocity (PWV) and arterial volume distensibility were assessed before and after intervention.

SETTING

Clinical ageing research unit, Newcastle University.

RESULTS

At baseline, there were no between-group differences in age, handgrip strength, clinic or 24-h ABP, BMI, waist circumference, fat mass, physical activity level, energy intake or urinary and plasma nitrate concentrations. After intervention, there were no significant effects on clinic systolic and diastolic BP or 24-h ABP, PWV (p=0.54), arterial volume distensibility (p=0.89), or ADMA (p=0.45).

CONCLUSIONS

IHGE or beetroot juice consumption for 7 days did not affect BP or peripheral arterial function in overweight and obese middle age and older adults. Ageing may reduce the effects of these interventions on vascular function and studies are needed to test this hypothesis.

Impact of physical activity interventions on blood pressure in Brazilian populations

Background

High blood pressure is associated with cardiovascular disease, which is the leading cause of mortality in the Brazilian population. Lifestyle changes, including physical activity, are important for lowering blood pressure levels and decreasing the costs associated with outcomes.

Objective

Assess the impact of physical activity interventions on blood pressure in Brazilian individuals.

Methods

Meta-analysis and systematic review of studies published until May 2014, retrieved from several health sciences databases. Seven studies with 493 participants were included. The analysis included parallel studies of physical activity interventions in adult populations in Brazil with a description of blood pressure (mmHg) before and after the intervention in the control and intervention groups.

Results

Of 390 retrieved studies, eight matched the proposed inclusion criteria for the systematic review and seven randomized clinical trials were included in the meta-analysis. Physical activity interventions included aerobic and resistance exercises. There was a reduction of -10.09 (95% CI: -18.76 to -1.43 mmHg) in the systolic and -7.47 (95% CI: -11.30 to -3.63 mmHg) in the diastolic blood pressure.

Conclusions

Available evidence on the effects of physical activity on blood pressure in the Brazilian population shows a homogeneous and significant effect at both systolic and diastolic blood pressures. However, the strength of the included studies was low and the methodological quality was also low and/or regular. Larger studies with more rigorous methodology are necessary to build robust evidence.

Effects of acute and chronic exercise in patients with essential hypertension: benefits and risks

The importance of regular physical activity in essential hypertension has been extensively investigated over the last decades and has emerged as a major modifiable factor contributing to optimal blood pressure control. Aerobic exercise exerts its beneficial effects on the cardiovascular system by promoting traditional cardiovascular risk factor regulation, as well as by favorably regulating sympathetic nervous system (SNS) activity, molecular effects, cardiac, and vascular function. Benefits of resistance exercise need further validation. On the other hand, acute exercise is now an established trigger of acute cardiac events. A number of possible pathophysiological links have been proposed, including SNS, vascular function, coagulation, fibrinolysis, and platelet function. In order to fully interpret this knowledge into clinical practice, we need to better understand the role of exercise intensity and duration in this pathophysiological cascade and in special populations. Further studies in hypertensive patients are also warranted in order to clarify the possibly favorable effect of antihypertensive treatment on exercise-induced effects.

Methodological quality of meta-analyses on the blood pressure response to exercise: a review

Numerous meta-analyses have been conducted to summarize the growing numbers of trials addressing the effects of exercise on blood pressure (BP), yet it is unclear how well they have satisfied contemporary methodological standards. We applied an augmented version of the Assessment of Multiple Systematic Reviews (AMSTARExBP) scale to 33 meta-analyses retrieved from searches of electronic databases. Qualifying reports used meta-analytic procedures; examined controlled exercise training trials; had BP as a primary outcome; and had exercise or physical activity interventions independently or combined with other lifestyle interventions. AMSTARExBP scores averaged near the middle of the scale (Mean = 56.0% ± 21.4% of total items possible); co-authored and more recent meta-analyses had higher quality scores. Common deficits were failures to disclose full search details (30% did), gauge the quality of included trials (48% did), use duplicate study selection and data extraction (55% did), or incorporate study quality in formulating results (35% did). Nearly all (91%) meta-analyses observed that exercise significantly lowered BP; fewer (58%) found that such effects depended on exercise or patient characteristics but these patterns often conflicted. Meta-analyses are often pillars of clinical recommendations and guidelines, yet only 58% addressed the clinical translations of their findings. In sum, meta-analyses have contributed less than ideally to our understanding of how exercise may impact BP, or how these BP effects may be moderated by patient or exercise characteristics. Future meta-analyses that better satisfy contemporary standards offer considerable promise to understand how and for whom exercise impacts BP.

Evidence for the role of isometric exercise training in reducing blood pressure: potential mechanisms and future directions

Hypertension, or the chronic elevation in resting arterial blood pressure (BP), is a significant risk factor for cardiovascular disease and estimated to affect ~1 billion adults worldwide. The goals of treatment are to lower BP through lifestyle modifications (smoking cessation, weight loss, exercise training, healthy eating and reduced sodium intake), and if not solely effective, the addition of antihypertensive medications. In particular, increased physical exercise and decreased sedentarism are important strategies in the prevention and management of hypertension. Current guidelines recommend both aerobic and dynamic resistance exercise training modalities to reduce BP. Mounting prospective evidence suggests that isometric exercise training in normotensive and hypertensive (medicated and non-medicated) cohorts of young and old participants may produce similar, if not greater, reductions in BP, with meta-analyses reporting mean reductions of between 10 and 13 mmHg systolic, and 6 and 8 mmHg diastolic. Isometric exercise training protocols typically consist of four sets of 2-min handgrip or leg contractions sustained at 20-50 % of maximal voluntary contraction, with each set separated by a rest period of 1-4 min. Training is usually completed three to five times per week for 4-10 weeks. Although the mechanisms responsible for these adaptations remain to be fully clarified, improvements in conduit and resistance vessel endothelium-dependent dilation, oxidative stress, and autonomic regulation of heart rate and BP have been reported. The clinical significance of isometric exercise training, as a time-efficient and effective training modality to reduce BP, warrants further study. This evidence-based review aims to summarize the current state of knowledge regarding the effects of isometric exercise training on resting BP.

Effect of isometric handgrip exercise training on resting blood pressure in normal healthy adults

INTRODUCTION

The aim of the present study was to study the effect of isometric handgrip (IHG) exercise training on resting blood pressure in normal healthy volunteers.

MATERIALS AND METHODS

Hand grip spring dynamometer was used for IHG exercise training. A total of 30 normal healthy volunteers in the age group of 20-40 y were enrolled for the study. Exercise training protocol consisted of five 3-min bouts of IHG exercise at 30% of maximum voluntary contraction separated by 5 min rest periods. Exercise was performed 3 times/wk for 10 wk. Subject's blood pressure was measured before and after exercise.

RESULT

There was a significant reduction in resting blood pressure following 10 wk of exercise training. Both Systolic and Diastolic blood pressure reduced significantly (p<0.001).

CONCLUSION

IHG exercise training might be a simple, effective, inexpensive and non-pharmacological method in lowering blood pressure.