Effects of heart rate variability biofeedback training on psychological state and cardiac autonomic regulation in stressed people

Abstract

IntroductionPsychological stress is common in our fast‐paced society and strongly influences mental and physical well‐being. Specific training methods have been recently proposed to deal with the negative effects of stress. heart rate variability biofeedback training, a method whereby the subject controls an unusually breathing rate to reach cardiac coherence, has been shown to reduce anxiety and improve cardiac autonomic dynamics in diseased people as well as in young competitors. The present study was designed to examine the effects of short sessions of biofeedback (BFB) training in subjects classified as being severely stressed.MethodsTwenty‐four participants characterized by a high level of state anxiety, were randomly assigned into a BFB group (n=12) or a control Group (n=12). In the BFB group, cardiac coherence training using a biofeedback device (URGOfeel®, URGOTECH) was conducted during 5 weeks, 5‐min twice a day.Subjects completed two sessions of tests (before and after 5‐weeks BFB training). Each session consisted in 4 conditions, a baseline “quiet” condition, a condition of cognitive tasks (to assess different domains of executive functioning), and two conditions of cognitive tasks associated to two levels of environmental‐induced stress. To create gradual level of environmental stress, the experimental context was modified by generating visual and sound interferences with negative feedback and time pressure. Heartbeat intervals were recorded (Polar Belt) for 10‐min both at baseline and after 5‐weeks BFB training and was assessed in temporal domain (RMSSD) and from non‐linear analyses (entropy index calculated from MultiScale Entropy, MSE). Participants filled out a series of questionnaires on‐line, notably the Spielberger state anxiety questionnaire (STAI) and the NASA‐TLX to measure the impact of stress on anxiety and workload, before and after each session and conditions.ResultsBefore BFB training the induced stress, was associated with a high level of anxiety and a low entropy when compared to baseline and cognitive tasks conditions. After BFB training, both psychological state and entropy in cardiac dynamics were improved in every condition.Conclusionthe present study confirms the blunting of physiological complexity in heart rate dynamics in stressed subjects especially under acute stress. The phenomenon is generally associated with an altered heart‐brain interconnectivity and a lesser adaptive capacity to everchanging environments. The main outcome here was the efficiency of (very) short BFB training sessions to restore an improved autonomic control in stressed subjects whatever their environment.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.