High-intensity handgrip training lowers blood pressure and increases heart rate complexity among postmenopausal women: a pilot study

The evidence of effectiveness of isometric resistance training on the management of hypertension in adults: an umbrella review

Hypertension is the leading risk factor for cardiovascular disease yet also one of the most readily preventable causes of death. Isometric resistance training (IRT) has gained increasing popularity in recent times as a viable nonpharmacological management option for hypertension. Whilst there have been several reviews on this topic, with varying findings, this umbrella review aimed to summarize the current evidence underpinning the effectiveness of IRT for hypertension. Quantitative systematic reviews and meta-analyses published in English were considered for inclusion. Commercially produced and grey literature was searched between December 2021 and January 2022. Methodological quality of included reviews was determined using the AMSTAR 2 critical appraisal tool. Customized data extraction tools were developed for this review and data were synthesized using the National Health and Medical Research Council FORM Framework. Twelve reviews published between 2011 and 2021 of varying methodological quality were identified. Isometric handgrip exercise training with four sets of 2-min contractions and 1 min rest period between each set was the most utilized intervention, undertaken three times per week for at least 8 weeks. Collectively, there is consistent evidence to indicate IRT has positive impacts on SBP and DBP as well as mean arterial pressure. These positive impacts were reported for normotensive as well as hypertensive individuals. Given IRT is a readily available, easy-to-use intervention with minimal financial cost, it could be considered a viable treatment option for people with, and at risk of, hypertension.

Association between handgrip strength and metabolic syndrome: A meta-analysis and systematic review

BACKGROUND

Although muscle strength has been reported to be associated with metabolic syndrome (MetS), the association is still controversial. Therefore, the purpose of this meta-analysis was to identify the association between handgrip strength (HGS) and MetS.

METHODS

Original research studies involving HGS and MetS from database inception to 20 May 2022 were selected from PubMed, Web of Science, Embase, China National Knowledge Infrastructure, Wanfang databases, and Chinese Biomedical Document Service System. The odds ratios (ORs) with 95% confidence intervals (CIs) of MetS for HGS were calculated using a random-effects model. A dose-response analysis was performed. Subgroup analysis and meta-regression were also conducted.

RESULTS

Thirty effect sizes (reported in 19 articles) with a total of 43,396 participants were included in this meta-analysis. All studies were considered to be of moderate-to-good quality. An inverse association between HGS (low vs. high) with MetS was shown (OR: 2.59, 95% CI: 2.06-3.25). Subgroup analyses demonstrated the pooled ORs of relative HGS (HGS/weight), relative HGS (HGS/BMI), and absolute HGS were 2.97 (95% CI: 2.37-3.71), 2.47 (95% CI: 1.08-5.63), and 1.34 (95% CI: 1.06-1.68), respectively. Dose-response analysis revealed a significant linear dose-response relationship between relative HGS (HGS/weight) and MetS in observational studies (0.1 HGS/weight: OR, 0.68; 95% CI: 0.62-0.75). Univariate meta-regression analysis indicated that country status, measuring tools of HGS, components of MetS, and diagnosed criteria of MetS explained 16.7%, 26.2%, 30.1%, and 42.3% of the tau-squared in the meta-regression, respectively.

CONCLUSION

The results of the current meta-analysis indicated that lower HGS is associated with a higher risk of MetS. A linear dose-response association between lower relative HGS (HGS/weight) and increased prevalence of MetS was found. Accordingly, a lower HGS is a significant predictor of MetS.

SYSTEMATIC REVIEW REGISTRATION

[https://www.crd.york.ac.uk/PROSPERO/], identifier [CRD42021276730].

Association of handgrip strength with the prevalence of metabolic syndrome in US adults: the national health and nutrition examination survey

OBJECTIVE

Aimed to find the cut-off point of handgrip strength and it's association with MetS.

RESULTS

The relative handgrip strength was negatively associated with the prevalence of MetS. Of note, the odds ratios (ORs) with 95% confidence intervals (CIs) across tertiles of relative handgrip strength were 1 (reference), 0.45 (0.33, 0.62), and 0.13 (0.08, 0.20) in male participants after adjusting for demographic factors, calorie intake, and physical activity. Similar results were observed in female participants. The cutoff values of relative handgrip strength for male and female participants were 0.52 and 0.40, respectively.

CONCLUSIONS

Findings of this study suggest that a strong relationship exists between handgrip strength and prevalence of MetS in US adults, regardless of sex.

METHODS

A total of 5 056 participants in the National Health and Nutrition Examination Survey were analysed in this study. Handgrip strength was measured by using a handgrip dynamometer. MetS was defined in accordance with the criteria of the scientific statement of the American Heart Association in 2009. Multivariable binary logistic regression was used to explore the association between handgrip strength and MetS.

Blood pressure lowering effects of a novel isometric exercise device following a 4-week isometric handgrip intervention

Background: Hypertension is the leading risk factor for global mortality. Isometric resistance exercise training reduces blood pressure (BP). However, the protocols used are often limited by cost/immobility and the use of rigid exercise modalities. In response, a novel more versatile, isometric exercise (IE) device, the IsoBall (IB) was created. Purpose: The aim of this study was to test the BP-lowering effectiveness of this prototype. Methods: Twenty-three healthy participants (29.10±2.19 years old, 173.95±3.83 cm, 75.43±5.06 kg, SBP 127.10±10.37 mmHg, DBP 70.40±6.77 mmHg) were randomly allocated to either a control group (CON) or 2 isometric handgrip (IHG) training groups that used the Zona plus (ZON) and IB devices. The intervention groups completed 3 sessions each week of 4, 2 min IHG at 30% maximal voluntary contraction, with a 1-min rest, for 4 weeks. Resting BP, heart rate (HR) and IHG strength were measured in all groups at baseline and postintervention. Results: Postintervention systolic BP (SBP) was significantly lower in both ZON (114.5±8.2 mmHg, p = 0.000) and IB (119.9±7.0 mmHg, p = 0.000) compared to control (131.0±12.4 mmHg). Postintervention diastolic BP (DBP) was reduced in both intervention groups (ZON 66.6±7.4 mmHg, p = 0.004; IB 65.7±10.0 mmHg, p = 0.012) compared to CON (71.1±8.8 mmHg). Mean arterial pressure (MAP) was reduced in both groups (ZON 82.6±6.8 mmHg, p = 0.000; IB 84.3±9.1 mmHg, p = 0.000) compared to control (91.0±9.7 mmHg). No significant changes were seen in HR or strength (p > 0.05). Conclusion: The results of this study indicate that both the ZON and IB devices elicit significant SBP, DBP and MAP reductions. Despite the ZON group having larger reductions in BP, no significant differences were found between the two devices. Thus, this study indicates the IB device to be an effective alternative to the ZON that can also be used to perform other IE modalities.

Handgrip strength is inversely associated with metabolic syndrome and its separate components in middle aged and older adults: a large-scale population-based study

BACKGROUND

Muscle weakness is followed by insulin resistance which is associated with metabolic disorders leading to metabolic syndrome (MetS). Therefore, muscle strength decline may be associated with MetS. The aim of this study was to investigate the relationships between muscle strength and MetS and its separate components.

METHODS

A cross-sectional study was performed in 17,703 participants aged 40 years and older living in Tianjin, China. Handgrip strength was measured using a handheld digital dynamometer. MetS was defined in accordance with the criteria of the American Heart Association scientific statements of 2009. Multiple logistic regression analyses were used to assess the association between handgrip strength and MetS and its separate components.

RESULTS

The overall prevalence of MetS was 33.6%. The prevalence of MetS was significantly higher in men than in women (41.6% vs 22.9%, P < 0.0001). After adjustment for potential confounding factors (including sociodemographic variables, lifestyle factors, total energy intake, and family history of disease), the odds ratios (95% confidence interval) of MetS across decreasing handgrip strength quartiles were: 1.00 (reference), 1.87 (1.66, 2.11), 2.40 (2.13, 2.71), and 3.36 (2.97, 3.80) in men and 1.00 (reference), 1.80 (1.48, 2.21), 2.77 (2.29, 3.36), and 3.89 (3.22, 4.71) in women, respectively (P for all trend <0.0001). Similarly, handgrip strength was also observed to be negatively associated with separate components of MetS both in men and women.

CONCLUSIONS

Muscle strength is inversely associated with MetS and its separate components. Further prospective studies are needed to confirm this issue.

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.