Isometric Handgrip Test Research Articles

Comparison of isometric handgrip test among pregnant offspring of hypertensive parents and pregnant offspring of non-hypertensive parents.

A family history of hypertension is one of the important risk factors for the development of pregnancy-induced hypertension (PIH). Offspring of hypertensive parents should be screened for PIH. The isometric handgrip (IHG) test is used to assess autonomic function among them. Autonomic function dysregulation can indicate their predisposition to develop PIH later in the course of pregnancy. To compare the IHG among pregnant offspring of hypertensive parents (Group 1) and non-hypertensive parents (Group 2). This is a cross-sectional study done among 100 pregnant women in the second trimester (50 participants in each group). Blood pressure responses to sustained hand grip for 2 minutes of maximum voluntary contraction (MVC) were recorded, immediately at the end of the IHG test and after 5 minutes of the IHG test. Independent t-test and Mann-Whitney U test were used to compare the responses in two groups. There is no statistical difference in basal blood pressure and heart rate between the two groups. Group 1 exhibited a significant increase in systolic blood pressure (SBP) and diastolic blood pressure (DBP) compared to Group 2 immediately after 2 minutes of the IHG test. There is a significant increase in SBP after 5 minutes of the IHG in Group 2. Offspring of hypertensive parents have increased sympathetic reactivity and restoration of the blood pressure is significantly less compared to offspring of normotensive parents, which may predispose them for PIH. IHG can be applied as a convenient tool to screen the population who are at risk of PIH in places like primary health centres or field screenings where IHG is one possible option.

Cardiovascular Autonomic Modulation in Chronic Coronary Syndrome Following Percutaneous Coronary Intervention.

Introduction The risk of sudden death in patients with chronic coronary syndrome (CCS) is increased by unbalanced cardiovascular autonomic function. Since myocardial ischemia appears to be the causeof this condition of autonomic dysregulation, treating this condition should improve and correct the autonomic functions. Improving myocardial perfusion by PCI might have beneficial effects on the recovery of autonomic balance in ischemia-triggered autonomic dysregulation. Objective In the present study, autonomic modulation in patients with CCS was evaluated before and after percutaneous coronary intervention (PCI) using cardiovascular reflex tests. Methods A total of 30CCS patients were recruited from the cardiology outpatient department. The patients were tested withcardiovascular reflex tests (lying to standing, 30:15 ratio, Valsalva ratio, isometric handgrip test, and deep breathing test) before and after PCI. The licensed statistical software SPSS version 21.0 was used to compile and analyse the data. Results Out of 30 patients, parasympathetic reactivity tests conducted post-PCI were significantly higher as compared to pre-PCI patients: (1) lying to standing - 30:15 ratio (1.17± 0.102 versus 1.03± 0.064, p=0.000); (2) Valsalva ratio (1.42±0.276 versus 1.02±0.133, p=0.000), (3) delta heart rate in deep breathing test (17.23± 3.004 bpm versus 7.85± 4.076 bpm, p=0.000), and (4) expiration to inspiration (E:I) ratio (1.25± 0.050 versus 1.11± 0.064, p=0.000. Among sympathetic reactivity tests, lying to standing test for fall in systolic blood pressure was significantly higher in the pre-PCI state than post-PCI (-20.73± 10.29 versus -2.33± 7.67, p=0.000). The rise in DBP of the isometric handgrip test was significantly higher in post-PCI compared to pre-PCI patients (36.73±8.39 mm Hg versus 16.63±8.47 mm Hg, p=0.000). Conclusion Resting autonomic tone as determined by cardiovascular reflex testing reveals an increase in both parasympathetic and sympathetic reactivity following PCI in CCS, according to the findings of this preliminary study. As a result, we propose that noninvasive procedures like cardiovascular reflex tests be used to stratify the likelihood of illness development in the future.

Effect of α-blockers on Handgrip Test Response of Diastolic Blood Pressure in Hypertensive, Benign Hypertrophy of Prostate Patients in a Therapeutics Clinic, Kolkata: A Cross-sectional Study.

The isometric handgrip (IHG) test is commonly used to detect sympathetic autonomic dysfunction. Tamsulosin, approved for the management of symptomatic benign prostatic hyperplasia (BPH), acts as an antagonist for α1-adrenergic receptors (α1-AR), whereas prazosin, an α1 receptor blocker, being less selective than tamsulosin, is used as an antihypertensive agent clinically. Our objective was to investigate if there is a distinction in blood pressure (BP) increase during IHG exercise between individuals with essential hypertension taking tamsulosin compared to those taking prazosin. A cross-sectional observational study was performed on 50 subjects receiving tablet prazosin and 47 subjects receiving tamsulosin, who were asked to undergo an IHG test. Pre- and posttest BP was recorded for both the groups, and the difference in diastolic BP (DBP) (delta DBP) was compared between the groups and to their respective baseline values. Post-IHG test, mean DBP was found to be 93.98 ± 9.13 mm Hg in the prazosin group and 101.00 ± 12.05 mm Hg in the tamsulosin group, respectively. The change of delta DBP in the tamsulosin group was significant, but the prazosin group showed an insignificant rise in DBP. Prazosin, being less selective than tamsulosin in terms of α1 receptor antagonism, showed suppression of BP during IHG. Tamsulosin demonstrates high selectivity for prostatic receptors while showing minimal affinity for vascular receptors. As a result, its impact on BP is expected to be minimal.

Systemic and ocular pressure changes following sympathetic activation in yoga practitioners - A comparative study

Introduction and Aim: Blood Pressure (BP), Intraocular Pressure (IOP) and Ocular Perfusion Pressure (OPP) are precursor parameters that lead to development of glaucoma. Under conditions of stress, either physical or psychological origin, there is disturbance of autonomic regulation. This causes increased activation of the sympathetic nervous system which might influence BP and ocular pressures. An altered autonomic balance towards lower sympathetic drive is observed in subjects practicing yoga, but it is not clear whether this adaptation also influences ocular pressures. Our study attempted to analyze variations in BP, IOP and OPP following sympathetic activation in yogic practitioners and non-practitioners of yoga. Materials and Methods: One hundred and ten subjects aged 18 - 25 years were recruited and categorised into yoga and non-yoga group. Basal BP was recorded using a sphygmomanometer and IOP was recorded using a rebound tonometer. Isometric hand grip (IHG) and Cold pressor test (CPT) were administered one at a time. IOP and BP were recorded immediately following these sympathetic activation tests. Mean arterial pressure and OPP was calculated using standard formula. Results: Significant increase in the values of pulse, BP, IOP and OPP following sympathetic activation were observed in the non-yoga group which was not noted in the yoga group. Elevation in systemic and ocular pressures following sympathetic activation was less in yoga practitioners. This adrenergic response was greater in the non-yoga group. Conclusion: Regular yoga practice maintains adequate perfusion of ocular tissues by autoregulation. Hence yoga can be recommended as a complementary health approach for the autonomic nervous system imbalance.

Heart rate dynamics and asymmetry during sympathetic activity stimulation and post-stimulation recovery in ski mountaineers-a pilot exploratory study.

There is a lack of studies on non-linear heart rate (HR) variability in athletes. We aimed to assess the usefulness of short-term HR dynamics and asymmetry parameters to evaluate the neural modulation of cardiac activity based on non-stationary RR interval series by studying their changes during sympathetic nervous system activity stimulation (isometric handgrip test) and post-stimulation recovery in professional ski mountaineers. The correlation between the changes in the parameters and the respiratory rate (RespRate) and also the duration of the career was analyzed. Short-term (5 min) and ultra-short-term (1 min) rates of patterns with no variations (0V), number of acceleration runs of length 1 (AR1), and short-term Porta's Index were greater, whereas Guzik's Index (GI) was smaller during sympathetic stimulation compared to rest. GI increased and the number of AR1 decreased during recovery. Greater increases in GI and RMSSD were associated with greater decreases in RespRate during recovery. Greater increases in RespRate from rest to short-term sympathetic stimulation were associated with greater increases in 0V (Max-min method) and AR1 but also with greater decreases in decelerations of short-term variance and accelerations and decelerations of long-term variance. Greater increases in 0V (Max-min method) and number of AR1 during sympathetic stimulation were associated with a shorter career duration. Greater decreases in these parameters during recovery were associated with a longer career duration. Changes in measures of HR dynamics and asymmetry, calculated based on short-term non-stationary RRi time series induced by sympathetic stimulation and post-stimulation recovery, reflected sympathovagal shift and were associated with condition-related alterations in RespRate and career duration in athletes who practice ski mountaineering.

Handgrip echocardiography predicts clinical outcomes in patients with ischemic mitral regurgitation

Abstract Background Mitral regurgitation (MR) is frequent in patients with ischemic heart disease and carries a dismal prognosis. Previous studies already demonstrated the prognostic benefit of bicycle exercise testing in patients with ischemic MR. Thus, current guidelines emphasize the role of exercise testing in patients with valvular heart disease. Isometric handgrip exercise resembles an alternative exercise intervention, that can also be performed in frail, comorbid patients. Until now, there are no data on the prognostic impact of handgrip echocardiography in heart failure patients with ischemic MR. Purpose To assess the prognostic benefit of isometric handgrip testing in heart failure patients with ischemic MR. Methods We prospectively enrolled patients with ischemic cardiomyopathy (left ventricular ejection fraction <50%) and at least mild MR that underwent echocardiography at rest and during handgrip exercise between January 2019 and September 2021. Patients were followed-up for one year to assess clinical outcomes. The combined endpoint included all-cause mortality, heart failure hospitalisation, ventricular assist device implantation (VAD), heart transplantation and mitral valve (MV) surgery/intervention. Results We included 133 patients (mean age was 75±10 years, 21% were female). Seventy patients (53%) presented with mild MR, while 54 patients had moderate MR (41%), and 9 patients (7%) showed severe MR at rest. Twenty-five patients (20%) with non-severe MR at rest, developed severe MR during handgrip exercise. One-year follow-up (median 321 (162-427) days) was complete in 128 patients (96%). Seventy-one patients (56%) experienced an adverse event: 13 patients (10%) died, 33 patients (26%) were re-admitted to hospital due to heart failure symptoms, 30 patients (24%) underwent MV transcatheter edge-to-edge repair, six patients (5%) received MV surgery, one patient (1%) underwent VAD implantation, and another three patients (4%) underwent heart transplantation. According to MR severity at rest, there was no difference in outcomes in patients with mild, moderate and severe MR (p=0.189). As expected, patients with severe MR at rest more often tended to undergo mitral valve surgery/interventions compared to the other groups (p=0.064). However, patients with non-severe MR at rest and exercise-induced severe MR presented with adverse outcomes similar to patients with severe MR at rest (p=0.005). Furthermore, patients with severe MR at rest and patients with dynamic severe MR underwent mitral valve surgery/interventions more frequently than patients with non-severe MR (p<0.001). Conclusion(s) In heart failure patients with ischemic MR, isometric handgrip testing unmasks severe MR in approximately every fifth patient with non-severe MR at rest. These patients showed similar clinical outcomes as compared to patients with severe MR already at rest. Thus, handgrip exercise testing might be a useful tool to guide further therapeutic decision making.

The Influence of Branched-Chain Amino Acid Supplementation on Fatigue and Tryptophan Metabolism After Acute and Chronic Exercise in Older Adults: Protocol for a Pilot Randomized Controlled Trial.

Fatigue is a strong predictor of negative health outcomes in older adults. Kynurenine, a metabolite of tryptophan, is strongly associated with fatigue. Reductions in fatigue are observed with exercise; however, exercise training does not completely alleviate symptoms. Branched-chain amino acids (BCAAs) have been shown to have advantageous effects on exercise performance and compete with kynurenine for transport into the central nervous system. Thus, the combination of BCAA and exercise may exert synergized effects of mental and physical fatigue. Therefore, we hypothesize that BCAA added to exercise will shift kynurenine metabolism toward enhanced synthesis of kynurenic acid, thereby reducing fatigue. This randomized, double-blind, placebo-controlled trial aims to compare the effects of acute (approximately 45 min) and chronic (8 wk) exercise with and without BCAA supplementation on mental and physical fatigue and assess whether the hypothesized outcomes are modulated by changes in kynurenine metabolism in 30 older adults (n=15, 50% per group). Older adults (aged 60-80 y) who do not exercise >2 days per week and self-report fatigue (≥3 on a scale of 1-10) will be recruited. Participants will be randomized to either the exercise+BCAA group or exercise+placebo group. Participants will engage in high-volume, moderate-intensity, whole-body exercise training (aerobic and resistance exercise; either in-person or web-based sessions) 3 times per week for 8 weeks. In addition, participants will consume daily either 100 mg/kg body weight of BCAA (2:1:1 leucine:isoleucine:valine) or placebo (maltodextrin) throughout the 8-week intervention. BCAA and placebo powders will be identical in color and dissolved in 400 mL of water and 2.5 g of a calorie-free water flavor enhancer. Muscle biopsies will be collected before and after the intervention after a 12-hour fast to examine changes in the biomarkers of tryptophan metabolism and inflammation. Our primary outcomes include changes in mental and physical fatigue and metabolism after the 8-week exercise training between the 2 groups. Mental and physical fatigue will be measured before and after the intervention. Mental fatigue will be subjectively assessed through the completion of validated questionnaires. Physical fatigue will be measured by isometric handgrip, 1-repetition maximum, chair rise, 400-meter walk, and cardiopulmonary exercise tests. The study was funded in March 2022, with an anticipated projected data collection period lasting from January 2023 through December 2023. The discovery that kynurenine concentrations are associated with fatigue and are responsive to BCAA supplementation during exercise training could have important implications for the development of future interventions, both lifestyle and pharmacologic, to treat fatigue in older adults. ClinicalTrials.gov NCT05484661; https://www.clinicaltrials.gov/study/NCT05484661. DERR1-10.2196/52199.

Parental History of Hypertension: A Risk for Autonomic Dysfunction and Metabolic and Vascular Derangement in Normotensive Male Offspring.

Children of hypertensive parents have an increased propensity of developing hypertension, at an age very much prior to their parents. Understanding the pathophysiology of hypertension in such young individuals, especially baroreflex sensitivity (BRS), is necessary. Reduced heart rate variability (HRV), insulin resistance (IR), dyslipidemia, and decreased vasodilatory adipokines, namely, apelin and relaxin, in normotensives may predispose to the onset of hypertension. Thus, this study compared autonomic functions, vascular markers, and metabolic profiles between normotensive male offspring with and without parental hypertension. This analytical cross-sectional study comprised 40 male normotensive offspring of hypertensive parents, aged 18-35 years, recruited as the study group and 40 age- and body mass index (BMI)-matched normotensive male offspring with non-hypertensive parents enrolled as controls. Cardiovascular autonomic functions, including BRS, HRV, diastolic blood pressure response to isometric handgrip test (ΔDBPIHG), Valsalva ratio, and metabolic and vascular markers, were assessed. The study group exhibited reduced BRS, HRV, and Valsalva ratio and higher ΔDBPIHG compared to controls, indicating impaired autonomic functions. The study group had higher IR and triglyceride levels and reduced apelin and relaxin levels. BRS showed significant correlations with HRV, Valsalva ratio, ΔDBPIHG, and metabolic and vascular markers. Normotensive male offspring of hypertensive parents exhibit impaired autonomic functions, as evidenced by reduced BRS, HRV, and Valsalva ratio. Additionally, they have higher IR, dyslipidemia, and decreased levels of vasodilatory adipokines, indicating an increased risk for future hypertension development. These findings signify that early identification of hypertensive potential in this high-risk population is warranted, which would enable taking necessary preventive measures.

Analysis of the force–time curve and median frequency of surface electromyographic signals during isometric hand grip test for estimation of a temporal pattern for muscle strengthening

This work presents methods developed for the analysis of dynamometric and electromyographic signals acquired during sustained maximal isometric hand grip tasks. In these analyses, we try to find a temporal pattern that could indicate the beginning of the decrease in hand grip strength. This information is essential for choosing the best isometric activity time for hand rehabilitation. The technique applied to the dynamometric signal was to find the time interval that precedes the drop of the isometric force RMS (root mean square) curve to values lower than the effective value. The technique applied to the surface electromyography (sEMG) signals was the identification of the instant when the lowest value of the median frequency of the signal occurs. The dynamometry data collection was carried out bilaterally in 19 men and 21 women. The electromyography data collection was carried out bilaterally in only 19 women. The statistical results (5% significance level) for the dynamometry data indicated that the time from the beginning of the test to the beginning of the decay of strength was approximately 7.6 $$\pm$$ 3.2 s, while the results for the sEMG data indicated that the time from the beginning of the test to the appearance of the lowest value of the median frequency was approximately 10.1 $$\pm$$ 2.9 s. The method of using the RMS values of the Force, presented by this work, found results of approximately 7 s, while the method most currently used (Median Frequency) found values of approximately 10 s. These results may help the rehabilitation professional to decide with more security the isometric time of exercises.

Assessment of Cardiac Autonomic Functions in Prehypertensive Individuals with and without a Family History of Hypertension: A Cross-sectional Study

Introduction: Individuals with prehypertension are at an increased risk of developing hypertension. Family history is one of the paramount non modifiable risk factors for developing hypertension. Hence, it becomes mandatory to assess the cardiac autonomic functions, which play an important role in the regulation of Blood Pressure (BP), in prehypertensive individuals with a family history. Aim: To compare the variations in parameters of cardiac autonomic function tests in prehypertensive individuals with and without a family history of hypertension. Materials and Methods: This cross-sectional study was conducted at the Institute of Physiology and Experimental Medicine, Madras Medical College, Chennai, Tamil Nadu, India from October 2020 to October 2021. The study included 30 prehypertensive individuals without a family history of hypertension and 30 prehypertensive individuals with a family history of hypertension, aged between 20 and 50 years, of both genders. They were recruited from the non communicable diseases Outpatient Department (OPD) at Rajiv Gandhi Government General Hospital, Chennai, Tamil Nadu, India. The prehypertensive range refers to a Systolic Blood Pressure (SBP) of 120-139 mmHg or a Diastolic Blood Pressure (DBP) of 80-89 mmHg. After obtaining informed consent, baseline parameters such as resting Heart Rate Variability (HRV) using AD instruments powerlab recorder, deep breathing test, Valsalva maneuver, isometric handgrip test, and Cold Pressor Test (CPT) were evaluated. The data obtained was statistically analysed using a Student’s t-test. Results: The mean age of prehypertensive individuals without a family history was 36.90±4.6 years, and in prehypertensive individuals with a family history, it was 36.43±5.3 years. The male to female ratio was higher. The resting SBP and DBP, as well as the basal heart rate, were significantly increased in the prehypertensive subjects with a family history. Time domain variables such as the mean RR, Root Mean Square of Successive Difference (RMSSD), and pRR50 were reduced in prehypertensive individuals with a family history. Among the frequency domain variables, the total power was reduced, while the low-frequency component and LF:HF ratio were significantly increased. The E/I ratio and Valsalva Ratio (VR) were also significantly reduced in prehypertensive individuals with a family history. Thus, the results emphasise that there is significant autonomic dysfunction in prehypertensive individuals with a family history of hypertension compared to prehypertensive individuals without a family history. Conclusion: Cardiac autonomic function tests in prehypertensive individuals with a family history indicate a definite sympathovagal imbalance in the form of sympathetic overactivity. This may substantiate the role of genetic predisposition in them. Chronic activation of the sympathetic nervous system makes them more prone to developing early hypertension.

Test-Retest Reliability and Sensitivity of Common Strength and Power Tests over a Period of 9 Weeks.

This study evaluated the reliability and sensitivity of a set of different common strength and power tests in a healthy adult population in a span of 9 weeks. Seventeen subjects (24.2 ± 2.2 years, 1.75 ± 0.10 m, 68.6 ± 14.2 kg, seven women) participated in the study. We tested countermovement jumps, reactive hops, and the maximal voluntary contraction (MVC) of handgrip and isometric knee extension. The tests were conducted in three separate sessions across a nine-week period, with one week between the first two sessions and eight weeks between the second and the third. Reliability and sensitivity statistics for each test were calculated for both the average of three trials and the best result during each session. The MVC of isometric knee extension and handgrip, as well as the countermovement jump test, demonstrated very high reliability and sensitivity over the nine-week period. The peak force of the reactive hops demonstrated high reliability but high sensitivity only for the average but not for the best result. The average contact time of reactive hops was neither a sensitive nor reliable measurement. In conclusion, isometric maximal knee extension and handgrip tests, as well as countermovement jumps and peak force of reactive hops, can be used as reliable and sensitive measurements of isometric and reactive strength and power over time periods of up to eight weeks. We recommend the use of the average results of three trials instead of the best performance value for longitudinal studies, as this procedure produces more consistent results and a lower measurement error.

Association between obesity and the functions of the autonomic nervous system in young adults

Obesity is one of the most prevalent public health issues. Excess weight has been associated with autonomic dysfunction, but the evidence in young adults is scarce. Therefore, this study aims to assess the relationship between the body mass index (BMI) and the autonomic nervous system (ANS) function in young adults. Males are known to have higher sympathetic nervous system activity as compared to females, who are known to have a greater parasympathetic function. Hence, it is critical to assess the differences in ANS activity based on gender. This study was done on 120 university students aged 18 - 25 years, categorized based on BMI as normal (18kg/m2-24kg/m2) and obese (>25kg/m2). The ANS function was assessed by performing the Isometric Handgrip Test (IHGT), Deep Breathing Test (DBT), and Cold Pressor Test (CPT). Our study revealed that obese individuals exhibited an increase in the blood pressure and heart rate as compared to normal individuals, indicating that the former might be at greater risk for the development of ANS dysfunction. Our study also revealed that obese males exhibited a greater change in their blood pressure as compared to their obese counterparts.

Effect of obesity on autonomic functions of Heart among healthy volunteers at a teaching Institute.

Obesity usually results from an imbalance between energy intake and energy expenditure, that is, energy homeostasis, which is controlled by the autonomic nervous system. This imbalance results from multifaceted interactions of genetic, physiological, behavioral, environmental, endocrine, nervous, metabolic factors, which lead to hemodynamic and metabolic alteration. To study the effect of obesity on the autonomic functions of the heart. An observational analytical study was carried out among 100 subjects. All healthy volunteers of 30-50 years were included. The subjects were grouped into two categories of body mass index (BMI): 30-39.99 kg/m2 as Obese group and BMI: 18.50-24.99 kg/m2 as Non -Obese group. Out of 100 subjects, 50 were obese and 50 were non-obese. The interview was taken. General physical examination and anthropometric measurements were recorded. The assessment of various cardiac autonomic function tests was carried out. Both groups were comparable for age and sex (P = 0.754). The resting heart rate, SBP, and DBP in the obese group were significantly higher compared to the non-obese group (P < 0.05). All values of autonomic function tests in the non-obese group were significantly higher compared to the obese group (P < 0.05) except for the Standing to lying ratio (P > 0.05). The values of SBP and DBP increased significantly in the non-obese people after the isometric handgrip test and cold press test compared to the obese people (P < 0.05). We conclude that the resting HR, SBP, and DBP were higher in obese people. However, after applying autonomic function tests, non-obese people respond better to these tests compared to obese people in the form of an increase in these parameters. Obesity is, thus, found to affect the autonomic function tests.

Impact of time-of-day and chronotype on neuromuscular performance in semi-professional female volleyball players

ABSTRACT This study aimed to determine if time-of-day could influence physical volleyball performance in females and to explore the relationship between chronotype and volleyball-specific performance. Fifteen young female athletes participated in a randomized counterbalanced trial, performing a neuromuscular test battery in the morning (9:00 h) and the evening (19:00 h) that consisted of volleyball standing spike, straight leg raise, dynamic balance, vertical jump, modified agility T-test and isometric handgrip tests. Chronotype was determined by the morningness-eveningness questionnaire. Compared to the morning, an increased performance was found in the standing spike (4.5%, p = .002, ES = 0.59), straight leg raise test (dominant-limb) (6.5%, p = .012, ES = 0.40), dynamic balance (non-dominant-limb) (5.0%, p = .010, ES = 0.57) and modified T-test (2.1%, p = .049, ES = 0.45) performance in the evening; while no statistical differences were reported in vertical jump tests or isometric handgrip strength. Moreover, no associations were found between chronotype and neuromuscular performance (r = −0.368–0.435, p = .052–0.439). Time-of-day affected spike ball velocity, flexibility in the dominant-limb, dynamic balance in the non-dominant-limb and agility tests. However, no association was reported among these improvements and the chronotype. Therefore, although the chronotype may not play critical role in volleyball-specific performance, evening training/matches schedules could benefit performance in semi-professional female volleyball players.

Evaluation of Sympathetic and Parasympathetic Tone and Reactivity in Adolescents with Specific Learning Disorder (Dyslexia).

To evaluate the autonomic function in specific learning disorder (SLD) and comorbid SLD attention-deficit hyperactivity disorder (SLD-ADHD). A cross-sectional study was conducted in a tertiary care hospital with 20 adolescent subjects each of confirmed SLD, SLD-ADHD, and healthy control (mean age 15.32 y). Heart-rate variability and autonomic-function tests were carried out using standard protocols. Heart-rate variability parameters, viz., mean RR interval, number of RR intervals which differ by ≥ 50ms (NN50), percentage NN50, standard deviation of differences between adjacent RR intervals, root square of mean of the sum of the squares of differences between adjacent RR intervals, coefficient of variance and absolute power of high-frequency band (HF) recorded apparently lower levels in SLD and SLD-ADHD as compared to healthy control indicating lower parasympathetic tone. Whereas, higher absolute power of low- frequency band (LF) in SLD and SLD-ADHD than healthy control indicated enhanced sympathetic activity. Higher LF/HF and lower SD1/SD2 ratios in SLD and SLD-ADHD than healthy control indicated higher sympathetic tone over parasympathetic tone. Values of autonomic-function tests such as E:I ratio, change in heart rate during deep-breathing test, 30:15 ratio, and Valsalva ratio showed a decrease in SLD and SLD-ADHD as compared to healthy control implying reduction in parasympathetic reactivity. Increased values for rise in diastolic blood pressure in the isometric handgrip test and cold pressor test recorded in SLD as compared to healthy control, revealed the increased sympathetic reactivity. Overall, results of heart-rate variability and autonomic-function tests imply dysregulation of sympathetic and parasympathetic activities with sympathetic dominance in SLD and SLD-ADHD.

Stressed in afterthought: Neuroendocrine effects of social self-threat during physical effort are counteracted by performance feedback after stress exposure

Social self-threat during physical stress, such as exposure to the cold pressor test and isometric handgrip test, has been shown to induce activation of the HPA axis, in addition to autonomic responses. However, previous research has suggested that dysfunctional post-event processing may play a major role in neuroendocrine reactivity at initial as well as subsequent social stress exposure. In the present study, we investigated how the interplay of context (i.e. performance feedback) with state (i.e., self-esteem) as well as trait-like factors (i.e., ruminative tendencies) affects stress responses to repeated, short bouts of physical activity. On two sessions, 1 week apart, 53 participants (27 women) performed an isometric handgrip task for 3 min, during which they were exposed to social-evaluative threat. In addition, participants received fake feedback on their performance immediately after the task, labeling it as either ‘above’ (positive) or ‘below average’ (negative). In addition to neuroendocrine (cortisol), cardiovascular (heart rate, blood pressure) and subjective stress reactivity, performance-related and social dimensions of state self-esteem were assessed before and after stress induction. Substantial increases in cardiovascular parameters were found on both days, regardless of feedback condition. However, positive feedback led to significantly diminished neuroendocrine responses on day 1, whereas baseline cortisol on session 2 was significantly higher in the negative feedback group. Conversely, social self-esteem decreased after stress induction on both days only for participants who had received negative feedback. Changes in self-esteem reported on day 1 were associated with increased baseline cortisol at the second session, while interindividual differences in self-reported (trait) rumination were associated with cortisol reactivity at session 1. Taken together, the results suggest that effects of social evaluation during short periods of physical stress rely on post-event processing and might be counteracted by positive appraisal directly after stress exposure. Post-hoc framing (in terms of success vs. failure) may predict subsequent stress-related hormonal effects better than task demands per se, which should be considered as a potential moderator in future acute stress research, but might also be relevant to many practical applications in fields ranging from sports/performance to health psychology.

The impact of isometric handgrip testing in left atrial reservoir function

Abstract Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): Fundação Adib Jatene Background Speckle tracking echocardiography (STE) allows accurate quantification of left atrial (LA) strain, thus allowing assessment of all phases of LA function (reservoir, conduit and contraction). Alterations in LA strain occur before changes in LA volumes, enabling early detection of LA dysfunction. In particular, the peak of LA strain during the reservoir phase (LASr) seems to be of prognostic value in heart failure. LASr is essential to pool enough blood volume to fill the LV during the subsequent diastole. The main determinants of LA reservoir function include blood volume arriving from the right ventricle, LA relaxation, and LA compliance. Still, changes in atrioventricular plane movement during the ventricular systole have been considered an additional factor influencing LASr. The relative contribution of left ventricular afterload to LASr, however, has yet to be clearly defined. Purpose We aimed to study the LA function during changes in LV afterload induced by the handgrip maneuver in subjects without heart disease, applying LASr and strain curve shape analysis. Material and Methods We studied 31 subjects (47 ± 15 years) without evidence of heart disease. A comprehensive 2D echocardiography was performed. We recorded 3 beat clips with standard STE views of LV and LA in baseline conditions and then during pressure overload-induced by left handgrip (42 ± 8 kg) combined with simultaneous pneumatic constriction of the right arm and both lower limbs. The LV GLS and LASr were calculated offline by a blinded examinator using commercially available software. Furthermore, we extracted the raw data of the strain curves and post-processed these signals using custom software. The global curves were split into different cardiac cycle phases using the valve opening and closure times(Figure 1). Quadratic functions estimated strain curves during the ejection phase due to the acceleration involved in the phenomenon. Quadratic function linear coefficients, a component of strain rate, were used to assess the shape of deformation curves. Results The handgrip maneuver caused mild reductions in LV strain: GLS baseline –19.07 % (±0.27) vs GLS handgrip -18.58% (±0.26) p = 0.02 (Figure 2A and C). Conversely, the LASr did not present significant changes: LASr baseline 33.82% (±0.84) vs LASr handgrip 32.96% (±0.85) p= 0.18 (Figure 2B and C). For the analysis of the shape of strain curves, we obtained data from 29 subjects. We found significant differences in LV ejection linear coefficient (ELC): LV ELC baseline –158.30 (±8.52) vs LV ELC handgrip –144.62 (±8.02) p = 0.02. For LA reservoir linear coefficient (RLC), we also found significant differences: LA RLC baseline 240.30 (±17.19) vs LA RLC handgrip 212.61 (±15.62) p = 0.03 (Figure 2D). Conclusion(s) The left atrial reservoir function is affected by changes in LV afterload induced by the handgrip maneuver. Our data suggest that LV pressure overload mainly impact the shape of LA strain curve rather than LASr. Abstract Figure 1 Abstract Figure 2

Effect of spirituality, exercise, music, and engagement with nature on intelligence, stress, and cognition

Background: Spirituality is recognition of a sense that there is something greater than myself. Physical exercise is any bodily activity that enhances physical fitness and overall health. Music is a universal language to express mind through tone and emotions. Nature is the physical world or the universe. Intelligence is the global capacity of the individual to act purposefully, to think rationally. Emotional intelligence is the ability to understand one’s own emotions and emotions of others. Adversity quotient deals with ability of a person to deal with adversities in life. Aims and Objectives: The present study was designed to study the effect of different interventions on intelligence, stress and cognitive functions. Materials and Methods: The present study was performed on 144 subjects in age group of 30–39 years. Their basal level of intelligence quotient (IQ), emotional quotient (EQ), resilience score (RS), acute stress score (ASS), perceived stress score (PSS), isometric handgrip (IHG), and stroop tests was recorded. The subjects were divided into four groups of 36 each. Four groups were allotted different interventions of spirituality practices, moderate intensity physical exercise, receptive music, and engagement with nature respectively for 1 month duration. Statistical analysis: ANOVA and post hoc tests along with student t-test were used for computing the results. Results: IQ, EQ, RS, ASS, IHG, PSS, and stroop subtests yielded mixed results with four interventions at different levels of significance. Conclusion: Although every intervention had different and positive impact on parameters, overall spiritual practices exhibited better response on parameters.

Physical Fitness as a Prognostic Marker for Infectious Events in Kidney Transplant Recipients

Introduction: Infectious events are one of the leading causes of death in kidney transplant recipients (KTRs). KTRs have reduced cardiorespiratory fitness (CRF), a predictor for infections in other populations. The aim of this study was to investigate whether CRF and muscle strength are prognostic markers for infectious events in KTRs. Methods: In this retrospective cohort study, 155 KTRs underwent an incremental, maximal cardiopulmonary exercise test (CPET) 3 months after transplantation. CRF was analyzed with peak oxygen consumption (VO₂ peak) while muscle strength with isometric handgrip (HG) test. Laboratory blood samples and drug therapy were collected. The median follow-up period was 54 (interquartile range 38–62) months. Cox regression analyses were performed to evaluate predictors of infectious events adjusting for potential confounders. Results: During this study, severe infectious events occurred in 41 subjects (26.5%). 15.5% (n = 24) of patients had a severely reduced CRF, defined as a VO₂ peak below the 5th percentile of the reference values reported for a matched healthy population. The hazard ratio for infectious events in this subgroup was 2.389 (95% CI = 1.188–4.801, p = 0.014), independently of gender, age, BMI, time on dialysis, hemoglobin concentration, eGFR, diabetes, and immunosuppressive regimen. On the contrary, no significant association of HG strength and infections was found. Conclusion: Therefore, low CRF may be considered as a modifiable predictor of severe infectious events in KTRs. A CPET should thus be recommended for cardiovascular screening, evaluation of CRF, and tailored exercise prescription to reduce the risk of infections and potentially improve long-term outcomes of transplantation.

Study of sympathetic and parasympathetic control of haemodynamics in mid pregnancy by cardiac autonomic neuropathy analyzer

Pregnancy is associated with substantial changes in cardiovascular system. The action of autonomic nervous system is essential for circulatory adaptations in pregnancy and nourishing growing fetus. The study was conducted to assess the significance of autonomic function tests amongst women of mid pregnancy and non pregnant women. A comparative study was caried out amongst pregnant and non pregnant women in Department of Physiology. A total of 60 women (30 pregnant as study group and 30 non pregnant healthy women as control group) aged between 18- 30 years were included in study. The results indicated that there was statistically significant change in resting heart and highly statistically significant change to deep breathing in mid pregnancy reflecting higher parasympathetic activity in study group (pregnant female) as compared to control group (non pregnant female) while sympathetic activity assessed by isometric hand grip test didn’t show any statistically significant change among pregnant as compared to non pregnant. Our study showed role of parasympathetic activity in controlling haemodynamics in mid pregnancy and it may help to return the arterial pressure to non pregnant level by causing haemodilution, although when the increase in activity is excessive, hypertension may ensue.