Hemodynamic Response to Isometric Handgrip Exercise in Adults with Intellectual Disability

Abstract

Introduction Individuals with intellectual disability (ID) have an increased risk of cardiovascular disease and reduced work capacity, which could partly be explained by alterations to autonomic and hemodynamic regulation. The measurement of heart rate and blood pressure during isometric handgrip (HG) exercise, a sympathoexcitatory stimulus, is a noninvasive method to investigate autonomic and hemodynamic alterations. The purpose of this study was to assess alterations to autonomic and associated hemodynamic regulation between individuals with ID and a matched control group during isometric HG exercise. Methods Individuals with ID (n = 13; 31 ± 2 yr, 27.6 ± 7.7 kg·m−2) and without ID (n = 16; 29 ± 7 yr, 24.2 ± 2.8 kg·m−2) performed 2 min of isometric HG exercise at 30% of maximal voluntary contraction (MVC) in the seated position. Blood pressure was averaged for 2 min before, during, and after HG exercise (mean arterial pressure [MAP], systolic blood pressure, and diastolic blood pressure). Heart rate variability, blood pressure variability, and baroreflex sensitivity were calculated from the continuous blood pressure and heart rate recordings. Results Isometric HG elicited a blunted response in systolic blood pressure, diastolic blood pressure, and MAP among individuals with ID compared with individuals without ID, even after controlling for strength (MAP: rest, HG, recovery; ID: 103 ± 7, 108 ± 9, 103 ± 7; without ID: 102 ± 7, 116 ± 10, 104 ± 10 mm Hg; interaction P < 0.05). Individuals with ID also had an attenuated baroreflex sensitivity response to HG exercise compared with individuals without ID (interaction P = 0.041), but these effects were no longer significant after controlling for maximal voluntary contraction. Indices of heart rate variability and blood pressure variability were not different between groups overall or in response to HG exercise (P > 0.05). Conclusions Individuals with ID have a blunted hemodynamic and autonomic response to isometric HG exercise compared with individuals without ID.

Cardiovascular and nitric oxide response after maximal voluntary isometric contraction in adolescents with and without Down Syndrome

“…The current investigators included the effect size to supply information concerning the p values. Sherman et al, (2021) showed similar findings in that individuals with ID had a blunted BP response to IHG exercise when compared to those without ID. Their MVC values were similar to the current sample, with a small difference between Research, Society and Development, v. 11, n. 1, e50011125342, 2022 (CC BY 4.0) | ISSN 2525-3409 | DOI: http://dx.doi.org/10.33448/rsd-v11i1.25342 groups (DS 2.24% higher and non-DS 6.44% higher).…”

“…Individuals with DS have a decreased pressor response which may be an indicator of reduced sympathetic activation during IHG; blunted BP and HR were observed in a group with DS compared to a control (Fernhall & Otterstetter, 2003). Individuals with ID may have difficulty maintaining perfusion pressure during IHG which may decrease metabolic demand and result in attenuated BP response (Sherman, et al, 2021). Similar results were found in our study, as previous studies have demonstrated an attenuated response of hemodynamic responses during IHG and in recovery in adults with DS (Kanokwan Bunsawat & Baynard, 2016;Fernhall & Otterstetter, 2003).…”

Changes in Short-Term and Ultra-Short Term Heart Rate, Respiratory Rate, and Time-Domain Heart Rate Variability Parameters during Sympathetic Nervous System Activity Stimulation in Elite Modern Pentathlonists—A Pilot Study

“…Sustained isometric exercise using a handgrip dynamometer has been commonly used by clinicians to compare cardiovascular and hemodynamic responses between groups of patients and healthy controls [ 27 , 29 , 50 , 51 , 52 ]. In athletes, isometric handgrip contraction has been used less frequently to evaluate cardiac autonomic modulation during physical exertion [ 53 ].…”

“…Increased HR during isometric exercise [ 21 ] is due to vagal withdrawal [ 6 , 18 , 22 , 23 ] concurrent with increased sympathetic activity [ 6 ]. Clinicians have analyzed cardiovascular and/or hemodynamic responses to isometric exercise in different groups of patients, mostly using protocols with 2–6 min of sustained handgrip strength exercise [ 24 , 25 , 26 , 27 , 28 , 29 ]. There is a lack of studies assessing autonomic response to handgrip isometric exercise in athletes and how the HRV alterations to handgrip exercise can be used to assess the sport performance.…”

The Effect of Progressive Resistance Exercise Training on Cardiovascular Risk Factors in People with Intellectual Disabilities: A Study Protocol

“…Studies indicate that the physiological responses to exercise are different in people with ID. For example, there are indicators that during exercise they have a blunted blood pressure and baroreflex sensitivity response [ 12 , 13 ], and a lower maximal heart rate and peak oxygen uptake [ 14 ] than people in the general population. Therefore, the effect of exercise interventions may differ for this population, and we cannot generalize the results from the general population to people with ID.…”