Effects of Yoganidra, Nadanusandhana and Deep Relaxation Technique on Heart Rate Variability

INTERVENTION: Intervention1: Yoga Nidra, Nadanusandhana, and Deep Relaxation Technique: Three relaxation practices‐Yoga Nidra, Nadanusandhana, and Deep Relaxation Technique will be given over three consecutive days, with one practice per day for 20 minutes. Each participant will receive all three practices. However, the sequence of practices will be randomized across participants, while all sessions will be conducted at the same time of day. Yoga Nidra will involve guided yogic relaxation inducing deep physical and mental relaxation with maintained awareness, Nadanusandhana will focus on A‐U‐M‐Om chanting and DRT will consist of systematic conscious relaxation and release of bodily tension. Intervention2: Yoga Nidra, Nadanusandhana, and Deep Relaxation Technique: Three relaxation practices, Yoga Nidra, Nadanusandhana, and Deep Relaxation Technique, will be given over three consecutive days, with one practice per day for twenty minutes. Each participant will receive all three practices. However, the sequence of practices will be randomized across participants, while all sessions will be conducted at the same time of day. Yoga Nidra will involve guided yogic relaxation inducing deep physical and mental relaxation with maintained awareness. Nadanusandhana will focus on A U M Om chanting. Deep Relaxation Technique will consist of systematic conscious relaxation and release of bodily tension. Control Intervention1: NA: NA CONDITION: PRIMARY OUTCOME: Increase in parasympathetic modulation as reflected by increases in time‐domain (RMSSD, SDNN) and frequency‐domain (HF power, LF power) HRV indices.Timepoint: 2 years SECONDARY OUTCOME: Reduction in relative low‐frequency dominance and overall autonomic arousal, reflected by a decrease in the LF/HF ratio following each relaxation practice.Timepoint: 2 years INCLUSION CRITERIA: Eligible participants will be 18‐ 40 years old, able to lie supine and rela Xquietly for 30 minutes, willing to abstain from caffeine, nicotine, and heavy meals for at least 3 hours before each session, and able to provide written informed consent.