A randomized controlled trial comparing home-based isometric handgrip exercise versus endurance training for blood pressure management

Isometric Exercise Training and Arterial Hypertension: An Updated Review

Hypertension is recognised as a leading attributable risk factor for cardiovascular disease and premature mortality. Global initiatives towards the prevention and treatment of arterial hypertension are centred around non-pharmacological lifestyle modification. Exercise recommendations differ between professional and scientific organisations, but are generally unanimous on the primary role of traditional aerobic and dynamic resistance exercise. In recent years, isometric exercise training (IET) has emerged as an effective novel exercise intervention with consistent evidence of reductions in blood pressure (BP) superior to that reported from traditional guideline-recommended exercise modes. Despite a wealth of emerging new data and endorsement by select governing bodies, IET remains underutilised and is not widely prescribed in clinical practice. This expert-informed review critically examines the role of IET as a potential adjuvant tool in the future clinical management of BP. We explore the efficacy, prescription protocols, evidence quality and certainty, acute cardiovascular stimulus, and physiological mechanisms underpinning its anti-hypertensive effects. We end the review with take-home suggestions regarding the direction of future IET research.

A blended face-to-face and eHealth lifestyle intervention on physical activity, diet, and health outcomes in Hong Kong community-dwelling older adults: a study protocol for a randomized controlled trial

Background

Aging individuals are vulnerable to various Noncommunicable Diseases (NCDs). Different behaviors are closely related to a decreased risk of suffering from NCDs: sufficient Physical Activity (PA) (e.g., at least 150 mins Moderate-to-vigorous Physical Activity (MVPA) per week) and a healthy daily diet (e.g., at least five portions of Fruit and Vegetable Intake (FVI), 5-6 taels (189.0-226.8 g) Meat, Fish, Egg and Alternatives (MFEA)). Traditional face-to-face interventions were effective in behavior change. However, it was revealed to be resource-intensive and limited transfer due to poor self-regulation skills outside of face-to-face sessions. Thus, eHealth could be a supplement for older adults outside traditional face-to-face settings. The blended approach combining these two interventions might optimize the intervention effects on lifestyle behavior initiation and maintenance, but little research can be found among Hong Kong older adults. Therefore, the study aims to test a blended intervention to promote PA, diet, and health outcomes among Hong Kong community-dwelling older adults.

Methods

This study will adopt a 10-week three-arm randomized controlled trial. The blended group will receive weekly (1) two 60-min face-to-face sessions with one for PA and one for diet, and (2) two web-based sessions with one for PA and one for diet. The face-to-face group will receive the same intervention content as the face-to-face sessions in the blended group. The control condition will receive a biweekly telephone call. The outcomes will include MVPA (minutes/week), FVI (portions/day), MFEA consumption (taels/day), social-cognitive factors (self-efficacy, planning, social support, action control), physical health outcomes (clinical indicators, senior physical fitness), mental health outcomes (depression, loneliness) and health-related quality of life. Data collection will be implemented at the pre-test, post-test, and 3-month follow-up test.

Discussion

This is the first study evaluating a blended intervention promoting multiple health behaviors among Hong Kong community-dwelling older adults. If the effect of the blended intervention is superior to the traditional face-to-face group and the control group, it will enrich lifestyle intervention approaches and can be applied to older adults, helping them obtain health benefits. Furthermore, a better understanding of mechanisms will also have implications for theory-building.

Clinical trial registration

https://www.isrctn.com/ISRCTN32329348, ISRCTN32329348.

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.

Short-term efficacy of non-pharmacological interventions for global population with elevated blood pressure: A network meta-analysis

Background

This study aims to compare the potential short-term effects of non-pharmacological interventions (NPIs) on prehypertensive people, and provide evidence for intervention models with potential in future community-based management.

Methods

In this Bayesian network meta-analysis, Pubmed, Embase, and Web of science were screened up to 16 October 2021. Prehypertensive patients (systolic blood pressure, SBP 120-139 mmHg/diastolic blood pressure, DBP 80-89 mmHg) with a follow-up period longer than 4 weeks were targeted. Sixteen NPIs were identified during the scope review and categorized into five groups. Reduction in SBP and DBP was selected as outcome variables and the effect sizes were compared using consistency models among interventions and intervention groups. Grade approach was used to assess the certainty of evidence.

Results

Thirty-nine studies with 8,279 participants were included. For SBP, strengthen exercises were the most advantageous intervention group when compared with usual care (mean difference = -6.02 mmHg, 95% CI -8.16 to -3.87), and combination exercise, isometric exercise, and aerobic exercise were the three most effective specific interventions. For DBP, relaxation was the most advantageous intervention group when compared with usual care (mean difference = -4.99 mmHg, 95% CI -7.03 to -2.96), and acupuncture, meditation, and combination exercise were the three most effective specific interventions. No inconsistency was found between indirect and direct evidence. However, heterogeneity was detected in some studies.

Conclusion

NPIs can bring short-term BP reduction benefits for prehypertensive patients, especially exercise and relaxation. NPIs could potentially be included in community-based disease management for prehypertensive population once long-term real-world effectiveness and cost-effectiveness are proven.

Systematic review registration

https://www.crd.york.ac.uk/PROSPERO/display_record.php?RecordID=151518, identifier: CRD42020151518.

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.

Comparison of different types of exercise training on resting blood pressure in 30-45 years old adults: a randomised controlled trial

Hypertension is the most metastasizing non-communicable disease, which has affected more than 1.4 billion people, worldwide. Exercise is the core management strategy for hypertensive individuals. Extensive literature is available for each kind of exercise that is isometric hand grip training (IHGT), resistance training (RT), and aerobic training (AT). However, the comparison between these exercise regimens has not been done in a single trial. The trial was conducted on 126 subjects in Hisar, an urban area of Haryana (INDIA), from July 2017 to December 2018. Subjects were randomly assigned to four groups: control (n=33), IHGT (n=32), RT (n=31), and AT (n=30). Study variables were measured at baseline, 2nd week, 4th week, 6th week, and also after the 8th week of intervention. Experimental groups showed significant reduction in all the components of blood pressure in comparison to control group. The RT group showed maximum reduction in blood pressure in comparison to other regimens (systolic blood pressure: RT > IHGT > AT; diastolic blood pressure: RT > AT > IHGT). However, the difference between the groups is not statistically significant (P>0.05). The study findings reveal that different kind of exercise regimens are equally effective in lowering blood pressure among pre hypertensive and stage 1 hypertension adults.

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 ).

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.

Is Low-Intensity Isometric Handgrip Exercise an Efficient Alternative in Lifestyle Blood Pressure Management? A Systematic Review

CONTEXT

High blood pressure is one of the leading preventable causes of cardiovascular death worldwide. In this regard, several studies have shown interest in the benefits of isometric exercise on blood pressure regulation.

OBJECTIVE

To assess whether low-intensity isometric handgrip exercise (LI-IHE) is an effective strategy to lower blood pressure levels in prehypertensive and hypertensive patients.

DATA SOURCE

This study was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement and registered with PROSPERO. Potentially eligible studies were identified after a systematic search conducted on 4 international databases: PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), PEDro, and SPORTDiscus.

STUDY SELECTION

We included randomized controlled trials that comprised patients who received LI-IHE.

STUDY DESIGN

Systematic review with meta-analysis.

LEVEL OF EVIDENCE

Level 3.

DATA EXTRACTION

Data related to patient characteristics, exercise programs, risk-of-bias assessment, and outcomes of interest were systematically reviewed independently by 2 authors.

RESULTS

The following reductions (mean differences) were observed after LI-IHE: systolic blood pressure (SBP), (MD) = -5.43 mm Hg; (95% CI, -8.47 to -2.39; P = 0.0005); diastolic blood pressure (DBP), -2.41 mm Hg (95% CI, -4.33 to -0.48; P = 0.01); mean arterial pressure (MAP), -1.28 mm Hg (95% CI, -2.99 to 0.44; P = 0.14).

CONCLUSION

LI-IHE seems to lower SBP, DBP, and MAP values in prehypertensive and hypertensive adults. It appears that LI-IHE reduces, in greater magnitude, blood pressure levels in hypertensive patients, specifically in patients aged <45 years, those who are overweight, and those on medications. Nevertheless, substantial heterogeneity in the main results and in the analyses by subgroups generated uncertainty about the real reduction magnitude that LI-IHE can produce on blood pressure.

Effects of isometric resistance training on resting blood pressure: individual participant data meta-analysis

Background:

Previous meta-analyses based on aggregate group-level data report antihypertensive effects of isometric resistance training (IRT). However, individual participant data meta-analyses provide more robust effect size estimates and permit examination of demographic and clinical variables on IRT effectiveness.

Methods:

We conducted a systematic search and individual participant data (IPD) analysis, using both a one-step and two-step approach, of controlled trials investigating at least 3 weeks of IRT on resting systolic, diastolic and mean arterial blood pressure.

Results:

Anonymized individual participant data were provided from 12 studies (14 intervention group comparisons) involving 326 participants (52.7% medicated for hypertension); 191 assigned to IRT and 135 controls, 25.2% of participants had diagnosed coronary artery disease. IRT intensity varied (8–30% MVC) and training duration ranged from 3 to 12 weeks. The IPD (one-step) meta-analysis showed a significant treatment effect for the exercise group participants experiencing a reduction in resting SBP of −6.22 mmHg (95% CI −7.75 to −4.68; P < 0.00001); DBP of −2.78 mmHg (95% CI −3.92 to −1.65; P = 0.002); and mean arterial blood pressure (MAP) of −4.12 mmHg (95% CI −5.39 to −2.85; P < 0.00001). The two-step approach yielded similar results for change in SBP −7.35 mmHg (−8.95 to −5.75; P < 0.00001), DBP MD −3.29 mmHg (95% CI −5.12 to −1.46; P = 0.0004) and MAP MD −4.63 mmHg (95% CI −6.18 to −3.09: P < 0.00001). Sub-analysis revealed that neither clinical, medication, nor demographic participant characteristics, or exercise program features, modified the IRT treatment effect.

Conclusion:

This individual patient analysis confirms a clinically meaningful and statistically significant effect of IRT on resting SBP, DBP and mean arterial blood pressure.

The efficacy of 'static' training interventions for improving indices of cardiorespiratory fitness in premenopausal females

PURPOSE

Cardiovascular disease (CVD) is the leading cause of death worldwide. Many risk factors for CVD can be modified pharmacologically; however, uptake of medications is low, especially in asymptomatic people. Exercise is also effective at reducing CVD risk, but adoption is poor with time-commitment and cost cited as key reasons for this. Repeated remote ischaemic preconditioning (RIPC) and isometric handgrip (IHG) training are both inexpensive, time-efficient interventions which have shown some promise in reducing blood pressure (BP) and improving markers of cardiovascular health and fitness. However, few studies have investigated the effectiveness of these interventions in premenopausal women.

METHOD

Thirty healthy females were recruited to twelve supervised sessions of either RIPC or IHG over 4 weeks, or acted as non-intervention controls (CON). BP measurements, flow-mediated dilatation (FMD) and cardiopulmonary exercise tests (CPET) were performed at baseline and after the intervention period.

RESULTS

IHG and RIPC were both well-tolerated with 100% adherence to all sessions. A statistically significant reduction in both systolic (- 7.2 mmHg) and diastolic (- 6 mmHg) BP was demonstrated following IHG, with no change following RIPC. No statistically significant improvements were observed in FMD or CPET parameters in any group.

CONCLUSIONS

IHG is an inexpensive and well-tolerated intervention which may improve BP; a key risk factor for CVD. Conversely, our single arm RIPC protocol, despite being similarly well-tolerated, did not elicit improvements in any cardiorespiratory parameters in our chosen population.

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.