Unpacking the Mechanisms: How Mindfulness Facets Shape Subjective and Biological Responses to Yoga Nidra Meditation

Abstract Objectives The effectiveness of mindfulness-based interventions can vary depending on individual characteristics. Higher baseline mindfulness may enhance receptivity to meditation practices such as Yoga Nidra. This study investigated whether trait mindfulness moderated the effects of Yoga Nidra interventions on stress, anxiety, depression, rumination, life satisfaction, sleep quality, and diurnal cortisol levels. Method Participants ( N = 255) were randomly assigned to either 11-min Yoga Nidra (EG1; n = 101), 30-min Yoga Nidra (EG2; n = 80), or an active music control group (ACG; n = 74). The intervention period was 8 weeks. Structural equation modeling was used to examine moderation effects, with mindfulness measured by the Five Facet Mindfulness Questionnaire (FFMQ). Results Higher trait mindfulness was associated with greater reductions in stress ( p = 0.006), and rumination ( p = 0.004) in the Yoga Nidra short-form group (EG1) and smaller decreases in total cortisol output ( p = 0.006) in the Yoga Nidra long-form group (EG2). The results in EG1 were mainly associated with the Describing facet. Nonjudging further predicted a greater decrease in anxiety ( p = 0.020) in EG1 and a greater increase in life satisfaction ( p = 0.024) in EG2. Observing predicted smaller gains in satisfaction with life ( p = 0.042) in EG2. Conclusions The findings highlight that individual mindfulness facets exert distinct influences on the psychological and physiological outcomes of Yoga Nidra. Describing and Nonjudging emerged as the most consistent moderators, reflecting mechanisms of emotional labeling and acceptance that align closely with Yoga Nidra. In contrast, Observing appeared to function particularly well in music-based interventions, where awareness unfolds without deliberate cognitive monitoring. These results emphasize the importance of trait mindfulness for understanding personalized mechanisms of relaxation and self-regulation. Preregistration This study was not preregistered in a publicly accessible registry.