Immediate effect of Deep Relaxation Technique (DRT) on Heart Rate Variability among Healthy individuals – A Randomized controlled trial

Deep Relaxation Technique (DRT) which is a form of Yogic Relaxation Technique developed at Swami Vivekananda Yoga Anusadhana Samsthan, Bengaluru was given for 20 minutes as an intervention. It is a systematic method of developing inner awareness. It emphasizes part-by-part relaxation of the whole body. It works at all levels of the existence of an individual at physical, mental, emotional, intellectual, and spiritual levels. It involves the relaxation of all body parts by directing the attention of the mind on different parts of the body starting from the toes to end up in the head region to propagate the relaxation feeling. DRT is known to reduce the state of anxiety and to improve sustained attention, also helps to improve sleep quality.  The practice of relaxation techniques has been shown to modify the autonomic response to mental stress which is generally termed as relaxation response, that tends to restore the altered sympatho-vagal balance towards normal. Probable 3 physiological mechanisms in meditation would be sensory attenuation, motor attenuation, and nonanalytical thinking, evoking minimal cortical activity. Heart rate variability (HRV) measures the beat-to-beat changes in heart rate and provides information on how the parasympathetic and sympathetic nervous systems control the cardiovascular system. Through the sinoatrial (SA) node, increased sympathetic nervous system activity raises heart rate, whereas increased parasympathetic nervous system (vagus nerve) activity lowers heart rate. Though the multifaceted physiological and psychological health benefits of both short- and long-term yoga training are quite well established, only very few studies have reported on the immediate effects of a single session.