Abstract

Background and objectives: Stress is a huge problem in today’s society. Although stress has a psychological origin, it affects several physiological processes in the human body causing changes in the heart rate variability, hypothalamic pituitary adrenal axis and concentration of several hormones in the body.1 Stress induces increased levels of cortisol. Studies reveal that salivary cortisol level measurement is the most accepted sample for cortisol analysis inmental stress conditions.2 Heart rate variability can be used as an indicator to assess the autonomic nervous system’s role.3 Heart rate variability biofeedback (HRVBF) is a method that showed improvements in cognitive performance resulting from the slowed respiratory rate and increased heart rate variability. Objectives were to study the effect of a brief heart rate variability biofeedback session on salivary cortisol reactivity to mental stress, and to devise an effective and practical tool to assess and to devise an interventional tool that might act as a coping strategy that can be used as a treatment in stress and anxiety management program.4 Methods: Thirty healthy male subjects of 20 to 45 years age were included in study. On Day 1 the subject was introduced to HRVBF, including its benefits and techniques, and their resonance frequency was determined. On Day 2, subject came without taking tea or breakfast, baseline physiological parameters were recorded (R1) and salivary sample for cortisol was collected, followed by a mental arithmetic test7 (MAT-I). Post-test, the same parameters were (T1) recorded again. The subject was then asked to relax for 10 minutes and physiological parameters (R2) were taken before undergoinga 10-minute HRV biofeedback session, breathing at their resonance frequency. Then, they were subjected to another mental arithmetic test (MAT-II), and the physiological parameters (T2) were measured and saliva sample was collected again. The reactivity was assessed by comparing pre (T1-R1) and post-HRV Biofeedback (T2-R2) data. Salivary cortisol reactivity is measured as the difference between cortisol levels before and after mental arithmetic test. Results: The Mean salivary cortisol reactivity after 10 minutes of HRV biofeedback intervention was less than that of salivary cortisol reactivity before intervention. Conclusion: The Heart rate variability biofeedback intervention causes decrease in stress levels which was measured by comparing the salivary cortisol reactivity. In our study, 30 subjects who are in the age between 20 and 45 years. We found adecrease in the salivary cortisol reactivity to mental stressafter 10 minutes of HRVBF intervention.

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