Effects Of Isometric Handgrip Exercise Research Articles

Effect of Isometric Handgrip Exercise on Diastolic Function in Pediatric Heart Transplant Recipients

Pediatric heart transplant recipients (HTR) have reduced exercise tolerance and diastolic dysfunction at rest despite normal ejection fraction. In adult HTR the impaired diastolic function is related to peak exercise tolerance, but this relationship is poorly understood in pediatric HTR. To determine the effects of low‐grade exercise stress on diastolic function in pediatric HTR, we tested the hypothesis that diastolic function would be augmented during isometric handgrip exercise.MethodsSeven pediatric HTRs were studied (mean±SD age: 10±3 yrs; sex: 3F, 4M; time since transplant: 5.4±2.1 yrs; left ventricular mass: 68±19 g/m2; end‐diastolic volume: 42±6 mL; end‐systolic volume: 12±2 mL; ejection fraction: 71±9 %). Pulsed Doppler was used to quantify early (E) and late (A) diastolic inflow velocities, deceleration time and slope. Tissue Doppler imaging of the lateral mitral annulus was used to assess velocity during early diastole (e′) and late diastole (a′). Left ventricular filling pressure responses were estimated using the early diastolic mitral valve inflow velocity/early diastolic lateral wall tissue velocity ratio (E/e′). Resting diastolic assessment was performed followed by 2 min of isometric handgrip exercise at 30% maximal voluntary contraction with diastolic function re‐assessed during the last 30 s of exercise.ResultsHeart rate (92±10 to 105±13 bpm; P=0.01) and mean arterial pressure (73±7 to 90±21 mmHg; P=0.035) increased from rest to exercise. There was no significant change in E/A (2.2±0.8 to 2.2±1.1; P=0.831), deceleration time (0.183±0.031 to 0.173±0.035 s; P=0.529), deceleration slope (613±152 to 619±169 cm/s2; P=0.926), e′/a′ (2.8±0.7 to 2.5±1.2 cm/s2; P=0.433), or E/e′ (7.02±1.37 to 7.13±1.71; P=0.709) from rest to exercise.ConclusionPediatric HTR have diastolic dysfunction at rest that is not augmented during low‐grade handgrip exercise stress.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Isometric handgrip exercise training attenuates blood pressure in prehypertensive subjects at 30% maximum voluntary contraction.

Prehypertension highlights a category of subjects who are at high risk of developing hypertension. This study assessed the blood pressure attenuating effect of isometric handgrip exercise in the management of prehypertension. A total of 400 prehypertensive subject with a mean age of 40 ± 10 years and recently diagnosed as prehypertension were recruited for the study. They were randomly distributed into exercise and control groups (n = 200). The control group was placed on lifestyle modification only, while the exercise group performed a 24 consecutive days isometric hand grip exercise training at 30% maximum voluntary contraction (MVC) for 2 min each day in combination with lifestyle modification protocol. The results show a statistically significant reduction in systolic blood pressure (SBP) and diastolic blood pressure (DBP). The exercise group had a mean reduction of 7.48 ± 0.06 and 6.41 ± 1.01 mmHg of the SBP and DBP, respectively. It was further observed that both the SBP and DBP and pulse rate significantly increased acutely within 5 min post exercise at 30% MVC with a mean value of 8.60 ± 0.20 mmHg, 7.33 ± 0.03 mmHg, and 8.24 ± 0.20 beats/min of the SBP and DBP and pulse rate, respectively. However, this increase returned to pre-exercise value within 10 min post exercises to a mean value of -0.68 + 1.64 mmHg, 1.48 ± 1.02 mmHg, and 3.00 ± 0.11 beats/min, respectively. This study has shown that isometric handgrip exercise is effective in the attenuation of blood pressure in prehypertensive subjects especially when combined with the routinely recommended lifestyle modifications. However, caution should be taken when recommending it because of acute increase in blood pressure.

Effects of Isometric Handgrip Exercise versus Aerobic Exercise on Arterial Stiffness and Brachial Artery Flow-Mediated Dilation in Older Hypertensive Patients

Effects of Isometric Handgrip Exercise versus Aerobic Exercise on Arterial Stiffness and Brachial Artery Flow-Mediated Dilation in Older Hypertensive Patients

Effects Of Habitual Isometric Handgrip Exercise On Central Blood Pressure In Older Adults

Central (aortic) blood pressure (BP) is a more important predictor of cardiovascular diseases than peripheral (brachial) BP. Isometric handgrip exercise can effectively decrease peripheral BP. However, effects of isometric handgrip exercise on central BP remain unknown. PURPOSE: The present study aimed to determine whether habitual isometric handgrip exercise decreases central BP in older adults with stage 1 and 2 hypertension. METHODS: Twenty-four males and females (mean age 63±2 y; ± SEM) with stage 1 and 2 hypertension (brachial systolic or diastolic BP of 140-179 or 90-109 mmHg, respectively) who were not actively involved in regular resistance or endurance training were randomly assigned to a group that did isometric handgrip exercise (IHG) or a control (CON) group. The isometric handgrip exercise comprised four unilateral 2-min isometric contractions at 30% of maximal voluntary contraction using a programmed handgrip dynamometer with 1-min rest periods for five days per week for four weeks. Central systolic BP (cSBP), brachial systolic BP (bSBP), brachial diastolic BP (bDBP), and the augmentation index at a heart rate of 75 beats per minute (AIx75) were non- invasively measured after resting in the supine position for at least five minutes in both groups before (baseline) and after four weeks of training using an automated applanation tonometric system. RESULTS: Baseline cSBP, bSBP, bDBP, and AIx75 did not significantly differ between the groups. Consistent with previous studies, bSBP and bDBP after training significantly decreased from baseline from 155±3 to 142±3 mmHg and from 94±3 to 88±2 mmHg, respectively (p<0.05 for both). The cSBP and AIx75 did not change in the CON group, but significantly decreased from baseline after training in the IHG group from 165±4 to 148±4 mmHg and from 88±4% to 82±4%, respectively (p<0.05 for both). The cSBP was significantly lower after training in the IHG than in the CON group (148±4 vs. 159±3 mmHg, p<0.05). CONCLUSIONS: These results suggest that isometric handgrip exercise could reduce central BP in older adults with stage 1 and 2 hypertension. Therefore, isometric handgrip exercise might be an effective non- pharmacological therapy for prevention and treatment of cardiovascular disease.

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.

Low-intensity isometric handgrip exercise has no transient effect on blood pressure in patients with coronary artery disease

Hypertension is highly prevalent among patients with coronary artery disease (CAD). Exercise-based cardiac rehabilitation reduces blood pressure (BP). However, less is known about the transient effect of a single bout of exercise on BP. Isometric handgrip exercise has been proposed as a new nonpharmacologic tool to lower BP. We aimed to investigate the acute effect of isometric handgrip exercise on BP in CAD patients. Twenty-one male CAD patients were included. All patients completed two experimental sessions in random order: one control and one low-intensity isometric handgrip session. BP was measured by means of a 24-hour ambulatory BP monitor preintervention, for 1 hour in the office and subsequently for 24 hours. Our results suggest that isometric handgrip exercise performed at low intensity is safe in patients with CAD but does not induce a transient reduction in BP.

Acute Effects of Isometric Handgrip Exercise on Blood Pressure and Heart Rate Variability

Isometric handgrip (IHG) exercise has been shown to elicit post‐exercise hypotension and transient improvements in heart rate variability (HRV) after one session. Typical IHG efforts are held at 30% of maximal voluntary contraction (MVC), with few studies deviating from this intensity. The purpose of this study is to assess the acute effects of different IHG exercise intensities on blood pressure (BP) and HRV. In a crossover study, 20 participants (18–30 years of age) will complete two IHG exercise protocols: (1) four 2‐min isometric contractions at 30% MVC with 2‐min rest periods using the dominant arm, and (2) four 45‐s isometric contractions at 50% MVC with 1‐min rest periods using the dominant arm. BP and HRV will be recorded using a continuous noninvasive arterial pressure (CNAP) monitor and three lead electrocardiography (ECG), respectively, at pre‐exercise, 5‐min post‐exercise, and 15‐min post‐exercise. BP will also be recorded continuously during both exercise protocols to measure BP responses after each IHG contraction. Statistical analysis for BP and HRV will be performed using a 2 × 3 repeated measures ANOVA. Secondary analysis of BP at the end of each isometric contraction will be conducted using a 2 × 5 repeated measures ANOVA. Statistical significance will be set to P &lt; 0.05.

Cardiovascular Responses to an Isometric Handgrip Exercise in Females with Prehypertension.

Background:Hypertensive individuals are known to exhibit greater increases in blood pressure during an isometric handgrip exercise (IHE) than their normotensive counterparts.Aim:This study tests the hypothesis that, compared to normotensive individuals, prehypertensive individuals exhibit an exaggerated response to IHE.Materials and Methods:In this study, the effects of IHE were compared in matched prehypertensive vs. normotensive healthy African-American females. Six healthy young adult African–American female university students were screened in a physician's office for blood pressure in the range of prehypertension, systolic blood pressure (SBP) 120–139 mmHg and diastolic blood pressure (DBP) 80–89 mmHg. Six young adult African–American women were also recruited to serve as a healthy normotensive control group with SBP ≤119 mmHg and DBP ≤79 mmHg. Cardiovascular fitness was determined by peak oxygen uptake (VO2 peak) measured during a progressive exercise test.Results:During the handgrip exercise, the prehypertensive group exhibited greater increases in SBP (from 139 ± 6 to 205 ± 11 mmHg, +48%) than the controls (from 132 ± 3 to 145 ± 3 mmHg, +10%); intergroup difference P < 0.001. The prehypertensive group also exhibited greater increases in DBP (from 77 ± 2 to 112 ± 5 mmHg, +46%) compared to the controls (from 72 ± 3 to 78 ± 4 mmHg, +8%); intergroup difference P < 0.001. The increase in systemic vascular resistance was also greater in the prehypertensive group (from 1713 ± 91 to 2807 ± 370 dyne.s.cm-5, +64%) than in the controls (from 1668 ± 80 to 1812 ± 169 dyne.s.cm-5, +9%); intergroup difference P < 0.05.Conclusion:These results suggest that blood pressure measurements performed during IHE may be a useful screening tool in evaluating prehypertensive individuals for antihypertensive treatments.

The impact of an experimentally induced increase in arterial blood pressure on left ventricular twist mechanics.

The effects of isometric hand-grip exercise (IHG) coupled with a period of postexercise circulatory occlusion (OCC; known to sustain exercise-induced increases in blood pressure while facilitating a decrease in heart rate) on left ventricular (LV) twist mechanics was examined. Two-dimensional speckle-tracking echocardiography was used to assess LV apical and basal rotation and LV twist in 19 healthy participants (23 ± 2 years old) at rest, during 3 min of IHG (performed at 40% maximal voluntary contraction) and 3 min of OCC immediately following IHG. The IHG elicited significant (P < 0.001) increases in mean arterial pressure (rest, 91 ± 1 mmHg; IHG, 122 ± 2 mmHg) and heart rate (rest, 65 ± 2 beats min(-1); IHG, 91 ± 4 beats min(-1)). Mean arterial pressure remained elevated during OCC (116 ± 2 mmHg; P < 0.001 versus rest), whereas heart rate returned to resting levels (68 ± 3 beats min(-1); P = 0.159 versus rest). Apical rotation decreased significantly (P < 0.01) by 10 ± 5% during IHG and 21 ± 4% during OCC, whereas basal rotation remained unchanged from rest. Left ventricular twist decreased from rest to IHG (12 ± 5%; P = 0.015) and OCC (21 ± 4%; P = 0.001), whereas a decrease in LV untwist rate was observed only during OCC. An increase in blood pressure generated by IHG, and maintained by a period of OCC, impairs aspects of LV twist mechanics. Postexercise circulatory occlusion isolated the effect of the arterial blood pressure rise (from heart rate), magnifying the impairment of LV twist mechanics when compared with IHG, whilst also negatively impacting LV relaxation. We propose that a protocol using isometric exercise followed by circulatory occlusion provides a method for studying the effects of blood pressure changes on LV twist mechanics.

Effect of isometric handgrip exercise on heart rate variability with and without somatosensory stimulation

Sub‐motor somatosensory electrical stimulation (STIM) of skeletal muscle increases heart rate variability (HRV). Short duration (&lt;30 sec) isometric handgrip exercise (HG) increases heart rate (HR) and decreases HRV largely through vagal withdrawal. The current study aimed to determine whether a gated effect exists when HG and STIM are combined. We tested the hypothesis that changes due to STIM would dominate over HG induced changes. Twelve volunteers (7 female; aged 24±2 yr.) performed 3 protocols: 1) four × 20s HG at 30, 40 &amp; 50% of their maximal voluntary contraction (MVC), 2) seven × 30s STIMs, and 3) a combination of HG+STIM. Compared to rest, STIM increased HRV (Rest: 61±80ms2, STIM: 69±84ms2, p&lt;0.05). In contrast, HRV decreased at all HG levels (ΔHRV@30%: −39±51ms2, 40%: −29±39ms2, 50%: −25±39ms2). The effects of HG were reversed during HG+STIM (ΔHRV@30%STIM: −1.7±40ms2, 40%STIM: 5.5±37ms2, 50%STIM: −4.2±19ms2, p&lt;0.05). Heart rate did not change during STIM (Rest: 59±7bpm; STIM: 58±6bpm). However HR increased above baseline and progressively at each level of HG (50% vs. 30%, p&lt;0.001; 50% vs. 40%, p&lt;0.001; 40% vs. 30%, p&lt;0.05). Heart rate was not different between HG and HG+STIM, p=0.095. The results indicate somatosensory stimulation can reverse the changes in HRV induced by handgrip suggesting muscle afferent signals may gate descending signals affecting heart rate variability. Funded by CIHR.

Effects Of Isometric Handgrip Exercise On Post-exercise Hypotension In Medicated Hypertensives.

Effects Of Isometric Handgrip Exercise On Post-exercise Hypotension In Medicated Hypertensives.

Hemodynamic Ventilatory and Metabolic Effects of Isometric Handgrip Exercise in Patients With Chronic Heart Failure

Hemodynamic Ventilatory and Metabolic Effects of Isometric Handgrip Exercise in Patients With Chronic Heart Failure

Hemodynamic ventilatory and metabolic effects of isometric handgrip exercise in patients with chronic heart failure

Hemodynamic ventilatory and metabolic effects of isometric handgrip exercise in patients with chronic heart failure

Effects of isometric handgrip exercise on Doppler-derived parameters of aortic flow in normal subjects

Effects of isometric handgrip exercise on Doppler-derived parameters of aortic flow in normal subjects

Haemodynamic effects of isometric handgrip exercise in patients convalescent from myocardial infarction.

1. Cardiac performance in response to 30% maximal isometric handgrip exercise was studied in fourteen patients convalescing uneventfully from a first myocardial infarction. In each patient, heart rate, mean arterial blood pressure and cardiac index were measured, and total peripheral resistance was calculated. The covariance of changes in the mean arterial blood pressure and cardiac index in these patients was matched against tolerance limits calculated from published data for normal subjects. 2. All patients had normal haemodynamic values at rest, and showed the usual rise of heart rate and mean arterial pressure during handgrip exercise. However, in six patients (group 1) the rise in mean arterial pressure was, as in normal subjects, accounted for mainly by a rise in cardiac index, with no consistent change in peripheral resistance. In eight patients (group 2), the mean arterial pressure rose to the same level as in group 1, but with a consistent increase in peripheral resistance and a smaller rise in the cardiac index. 3. It is suggested that in a substantial proportion of patients who are making a seemingly uncomplicated recovery from myocardial infarction, it may be possible to unmask an impairment of left ventricular function by means of isometric handgrip exercise.

Lack of effect of isometric handgrip exercise on the responses of the carotid sinus baroreceptor reflex in man.

1. The change in arterial pressure and heart rate resulting from alteration of carotid sinus transmural pressure by a median--34 mmHg and +33 mmHg by means of a variable-pressure neck chamber was tested in seven male volunteer subjects, at rest and during exertion of 35, 45 and 65% of maximum voluntary handgrip. 2. During 60 s of 35 and 45%, and during 30 s of 65%, of maximal voluntary handgrip there was virtually no alteration of the response of blood pressure to alteration carotid sinus transmural pressure. 3. The bradycardic response to increase in carotid sinus transmural pressure was reduced at various times after the commencement of handgrip at 45 and 65% of maximum voluntary contraction. 4. It is concluded that a reduction in arterial baroreceptor reflex sensitivy does not play an important role in the initiation of the increase in arterial blood pressure and heart rate caused by isometric exercise. 5. The hypothesis is advanced that some of the cardiovascular changes in exercise may result from elevation of the central 'set point' for blood pressure.

Effect of isometric hand-grip exercise on the carotid sinus baroreceptor reflex in man.

1. The changes in R--R heart interval that result from step-increase and step-decrease in carotid sinus transmural pressure induced by a variable pressure neck chamber were measured in seven normal men. Observations were made at rest, and during isometric hand-grip exercise at 24%, 44% and 64% of maximal voluntary contraction. 2. The response of heart interval to increase in carotid sinus transmural pressure was progressively and markedly diminished according to the strength of hand-grip. This effect was fully developed from the moment of onset of the exertion. 3. The response of heart interval to decrease in carotid sinus transmural pressure was much less consistently affected by hand-grip exercise.

Effect of isometric handgrip exercise on left ventricular function in the patient with artificial cardiac pacemaker.

The cardiovascular effects of isometric handgrip exercise were determined with a nonivasive method in the patient with artificial pacemaker. The arterial blood pressure was measured with mercury manometer as well as cardiac output by the dye dilution method with Indocyanin green before and after handgrip exercise. Isometric handgrip exercise produced a significant increase in the left ventricular ejection time, the left ventricular ejection time/the preejection period, the ejection time index/the isometric contraction time, the arterial blood pressure and cardiac output and a significant decrease in the preejection time and the isometric contraction time. Cardiac output was increased more remarkably in the negative Master two step test group than in the positive Master two step test group. There was found a significant positive relationship between the increase in cardiac output and P wave rate upon handgrip exercise.

等尺性握力負荷の左室機能に及ぼす影響

等尺性握力負荷の左室機能に及ぼす影響

Effects of Isometric Handgrip Exercise on Coronary Sinus Blood Flow in Idiopathic Cardiomyopathy

Coronary sinus blood flow (CSBF) was measured by the dye dilution method in 18 patients with idiopathic cardiomyopathy including 13 with hypertrophic type and 5 with congestive type, and the capacity for increasing CSBF in response to handgrip exercise was studied in 14 patients. CSBF at rest ranged from 41 to 236 ml/min/M2. Average CSBF of 114 +/- 12 ml/min/M2 (112 +/- 14 in hypertrophic type and 119 +/- 25 in congestive type) was significantly larger than control value of 77 +/- 6 presented previously (p less than 0.01). Handgrip exercise at 30% maximal effort for 3 min resulted in the increase in CSBF, averaging 23 +/- 8 ml/min/M2 (22 +/- 8%). However, in about one-half of cases, the percent increase in CSBF was much smaller than the percent increase in effort index which represents myocardial oxygen demand. The change of CSBF was not correlated with the changes of left ventricular systolic pressure, cardiac output, and stroke work. The diminished response of CSBF to isometric handgrip exercise was ascribed to the decreased coronary vascular reserve in this disorder.