Dynamic and Static Handgrip Exercise Increase Wave Reflection in Healthy Young Adults

Abstract

Increased wave reflection augments pulsatile load, wastes left ventricular effort, and is associated with cardiovascular events. Acute handgrip (HG) exercise increases central blood pressure and surrogate measure of wave reflection, augmentation index. However, surrogate measures of wave reflection do not provide a comprehensive assessment of pulsatile load and ventricular‐arterial interactions. Wave separation analysis can determine the relative contributions of forward (Pf) and backward (Pb) pressure wave amplitudes and reflection magnitude (RM=Pb/Pf) as well as the timing of apparent wave reflection return.PURPOSETo determine the effect of acute dynamic and static HG exercise on wave reflection magnitude and timing with wave separation analysis in young healthy adults.METHODSApplanation tonometry was used to record radial artery pressure waveforms in 31 adults (25±4 years) at baseline and during dynamic and static HG exercise in randomized order. Radial waves were calibrated to respective brachial mean and diastolic pressures and synthesized to central pressure waves using a generalized transfer function. Wave separation analysis was used to derive Pf, Pb, RM, and reflected wave transit time which was performed offline using a synthesized flow waveform.RESULTSCentral blood pressure and augmentation index increased with HG exercise as expected (p<0.05). Compared to baseline, both HG exercises increased wave reflection measures Pb (baseline 11.4±0.4 mmHg; dynamic 12.6±0.5 mmHg; static 12.7±0.6 mmHg, p<0.05) and RM (baseline 40±1%; dynamic 43±1%; static 44±1%, p<0.05), but not Pf (baseline 28.4±1.1 mmHg; dynamic 29.1±1.2 mmHg; static 28.8±1.2 mmHg, p>0.05). Reflected wave transit time was shortened with static but not dynamic HG exercise compared to baseline (baseline 95±4 ms; dynamic 90±3 ms; static 83±3 ms, p<0.05)CONCLUSIONBoth HG exercises increased measures of wave reflection (Pb and RM) suggesting greater wave reflection during HG exercise.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.