Voluntary heart rate lowering following a cardiovascular arousing task.

The purpose of the research was to evaluate the effect of feedback-assisted voluntary control to lower heart rate (HR), following a non-somatic mediated task designed to induce cardiovascular activation. Twenty-seven male subjects participated in this study and were randomly divided into three groups. All subjects were submitted to an arousing mental arithmetic task for a 1 min period, followed either by a feedback-assisted HR lowering task (FG), by an unassisted HR lowering task (ICG), or by a relaxation period (RCG). During this period (2 min duration), ICG and RCG subjects were required, as a help for HR deceleration or relaxation, to track visually a sweeping line similar in form to the continuous analogue feedback of the FG subjects. This sequence, interspaced by a 1 min rest period, was repeated 10 times. Results showed that the mental arithmetic task was effective in producing consistent and repetitive HR acceleration. All three groups showed significative HR lowering during the following voluntary HR control or relaxation period. However, there was no difference in the speed or depth of HR lowering. It appeared that continuous-analogue feedback was not more effective than instructions to relax to assist HR return to lower levels.