Biofeedback training versus simple instructions to reduce heart rate reactivity to a psychological stressor

Not All Competitions Come to Harm! Competitive Biofeedback to Increase Respiratory Sinus Arrhythmia in Managers

Despite the positive impact on achievement, competition has been associated with elevated psychophysiological activation, potentially leading to a greater risk of cardiovascular diseases. Competitive biofeedback (BF) can be used to highlight the effects of competition on the same physiological responses that are going to be controlled through BF. However, it is still unknown whether competition could enhance the effects of respiratory sinus arrhythmia (RSA)-BF training in improving cardiac vagal control. The present study explored whether competitive RSA-BF could be more effective than non-competitive RSA-BF in increasing RSA in executive managers, who are at higher cardiovascular risk of being commonly exposed to highly competitive conditions. Thirty managers leading outstanding private or public companies were randomly assigned to either a Competition (n = 14) or a Control (n = 16) RSA-BF training lasting five weekly sessions. Managers in the Competition group underwent the RSA-BF in couples and each participant was requested to produce a better performance (i.e., higher RSA) than the paired challenger. After the training, results showed that managers in the Competition group succeeded in increasing cardiac vagal control, as supported by the specific increase in RSA (p < 0.001), the standard deviation of R-R wave intervals (SDNN; p < 0.001), and root mean square of the successive differences between adjacent heartbeats (rMSSD; p < 0.001). A significant increase in the percentage of successive normal sinus beat to beat intervals more than 50 ms (pNN50; p = 0.023; η2 p = 0.17), low frequency (p = ≤ 0.001; η2 p = 0.44), and high frequency power (p = 0.005; η2 p = 0.25) emerged independently from the competitive condition. Intriguingly, managers who compete showed the same reduction in resting heart rate (HR; p = 0.003, η2 p = 0.28), systolic blood pressure (SBP; p = 0.013, η2 p = 0.20), respiration rate (p < 0.001; η2 p = 0.46), and skin conductance level (SCL; p = 0.001, η2 p = 0.32) as non-competitive participants. Also, the same reduction in social anxiety (p = 0.005; η2 p = 0.25), state (p = 0.038, η2 p = 0.14) and trait anxiety (p = 0.001, η2 p = 0.31), and depressive symptoms (p = 0.023, η2 p = 0.17) emerged in the two groups. The present results showed that managers competing for increasing RSA showed a greater improvement in their parasympathetic modulation than non-competing managers. Most importantly, competition did not lead to the classic pattern of increased psychophysiological activation under competitive RSA-BF. Therefore, competition could facilitate the use of self-regulation strategies, especially in highly competitive individuals, to promote adaptive responses to psychological stress.

Children's, Adolescents', and Young Adults' Heart Rate Reactivity to, and Recovery from, a Brief Psychological Stressor

Heart rate reactivity to a 2 minute mental arithmetic stressor delivered under timed and competitive conditions and graded for age-related difficulty was collected on 148 males and 153 females grouped into five age cohorts ranging from 7 to 20 years. Data on resting heart rate, heart rate during the stressor period, and post-stressor recovery showed significant sex (females had higher heart rates) and age effects (there was a general decrease in heart rate with age). There were no significant interactions between age and sex. Mean heart rate reactivity also showed significant variation with age, but no significant differences between males and females, nor any significant interaction between age and sex. The age effect for heart rate reactivity appeared to be a result of the oldest age group having significantly greater increases in heart rate than all other age groups.

Transfer of Heart Rate Feedback Training to Reduce Heart Rate Response to Laboratory Tasks

To examine whether transfer of heart rate (HR) feedback training to tasks not used during training could be improved by using multiple tasks during training, a modified multiple baseline across tasks, single subject design study was conducted using six high HR-reactive young adults. Participants received HR feedback training during the presentation of a videogame, and transfer of training was assessed to a mental arithmetic challenge and handgrip task. Transfer of training was next assessed following training with the mental arithmetic challenge and handgrip task. HR responses to each training task with no HR feedback were assessed during a pre-treatment session, an immediate post-training period following training on each task, a short delay (1-2 days) post-training session, and a long delay (1-2 weeks) post-training session. HR response to a novel speech task was assessed at pre-treatment and during short delay and long delay post-training sessions. Results revealed that participants reduced HR during training and generally maintained this reduction in HR during the immediate post-training assessment when HR feedback was not present. Participants were not able to reduce HR responses to tasks during short delay and long delay post-training sessions, and they were unable to transfer HR reduction skills to the speech task. Transfer of HR feedback training to new tasks was limited in nature and efforts to train across multiple stressors did not appear to improve transfer of training.

Psychosocial stress-induced heart rate reactivity and atherogenesis: cause or correlation?

The relationship between heart rate reactivity and atherogenesis is examined. Data from empirical studies are presented which support theoretical suggestions that it is the heart rate itself rather than the increase in heart rate following the onset of a stressor which is causally related to the development of arterial atherosclerosis. Several directions for research which will clarify this issue are discussed, with recent developments in the detection of atherosclerosis suggested as forming the basis of more reliable investigation of the effects of cardiac output variables upon arterial atherogenesis.

Age and gender differences in the relationship between heart rate reactivity and elevated serum lipids

Data on serum lipids and heart rate reactivity to a standardized mental arithmetic stressor were collected on 54 healthy men and 73 healthy women. Subjects' ages ranged from 18 to 61 years, allowing analysis of data from both young and older subgroups. MANOVA revealed that age was directly associated with elevated lipids in men and women. There was no significant relationship between reactivity and lipids for either older or younger men. Conversely, young women showed a significant direct relationship between reactivity and Total Cholesterol and LDL, but this was not present for older women. Implications of these data for the previously reported hypothetical relationship between reactivity and lipids are discussed. Limitations of the study are examined, and future directions for research suggested.

Maintenance and generalizability of laboratory-based heart rate reactivity control training

The maintenance over time (4 months) and generalizability (to a work setting) of laboratory-based heart rate reactivity control training was investigated. Forty-three subjects received 5 weeks of biofeedback, imagery, and breathing training and 41 subjects acted as controls. Although there were no significant differences between the reactivities of the control and those of the treatment subjects at any of three pretraining tests, significant differences were noted immediately following training, 7 weeks, and 4 months later, showing maintenance effects. Data collected during work activities on the frequency of reactivity of a magnitude similar to that in the laboratory also showed that treatment subjects had significantly fewer incidents of reactivity than control subjects after training. Followup interviews with treatment subjects indicated that lifestyles were also enhanced in a variety of areas, suggesting that the training had wider benefits. Issues for further research are discussed.

Differences in pulse rate and heart rate and effects on the calculation of heart rate reactivity during periods of mental stress

Heart rate and reactivity from pulse and ECG were compared over rest and mental arithmetic periods of 2-min duration each for 32 males and 50 females. Data from the two sources of heart rate were not significantly different during the rest period but did differ significantly during periods of heart rate acceleration and deceleration. Sex effects were also noted, with females having consistently higher heart rates from both sources of measurement. Calculation of heart rate reactivity via five procedures based upon the wider literature revealed significant differences between data from different sources of heart rate. Implications for assessment of heart rate reactivity to laboratory stressors are discussed, with suggestions for future research.

Developmental and gender differences in the relationship of behavior pattern to heart rate reactivity between two teenage samples

The Type A Behavior Pattern was assessed for 122 teenagers from two age-groups. Subjects had their heart rate measured during rest and presentation of a mental arithmetic stressor under timed and competitive conditions. Data were analyzed to determine whether sex, age, task performance, and behavior pattern predicted the degree of heart rate reactivity shown by these children. Although there were no significant main effects for behavior pattern, sex, or age, there was a significant interaction among age, sex, and behavior pattern. It is suggested that the two age groups of teenagers sampled here differ in the relationships they show between behavior pattern and heart rate reactivity. This result challenges some previous assumptions with regard to the homogeneity of teenagers on this issue.

Reducing heart rate reactivity to stress with feedback. Generalization across task and time

Heart rate (HR) reactions to two behavioral stressors (videogame and mental arithmetic) were measured in 8 experimental subjects who received biofeedback training and 8 matched control subjects during three assessment periods: pretraining, posttraining, and one-week follow-up. Experimental subjects exhibited significant reductions in HR following a training session in which they received ongoing HR feedback while playing a videogame. Control subjects, who played the same number of videogames without HR feedback, showed smaller HR reductions. During the training session, all subjects were instructed to reduce HR while maximizing game performance. In comparison to controls, experimental subjects (a) maintained lower HRs during videogame presentations after a one-week period and (b) generalized these HR reductions to the mental arithmetic challenge at follow-up. Performance on the videogame declined from posttraining to follow-up for experimental subjects but not for control subjects. No group difference in mental arithmetic performance was observed.

Incidence of laboratory-based heart rate reactivity during typical daily events

Heart rate reactivity to a standardized laboratory stressor (mental arithmetic under timed and competitive conditions) was measured in 37 men and women, drawn from white- and blue-collar occupations. In addition, heart rate reactivity data during 4 hr of work were gathered on each of these subjects and analyzed to determine (1) the presence during work time of reactivity equal to or greater than that to the mental arithmetic stressor; (2) the incidence of reactivity of 5, 10, 15, and 20 bpm during work time, and (3) the predictability of frequency of work time reactivity by mental arithmetic reactivity. Data suggested that, although there were several incidences of heart rate reactivity responses during work which were similar to those noted in the laboratory, these work heart rate responses were not able to be significantly predicted by laboratory heart rate responses.

Relative cardiac cost and physical, mental and psychological work load among a group of post-operative care personnel

Continuous registration of heart rate and careful minute-by-minute observation of all physical, mental and psychological job-related events was carried out in a group of nine post-operative care personnel. The relative cardiac cost (RCC) correlated significantly with the observed work events. The magnitude of participation of physical, mental and psychological work elements in the changes in RCC varied in the investigated subjects according to the type and magnitude of the different work events. However, collective data on the group indicated that changes in RCC were related mainly to physical effort and to a lesser, albeit significant, extent to psychological reaction. The results indicate the possibility of using the heart rate in monitoring working conditions and, probably, in guiding their improvement.