The Effects of Mindfulness-Based Stress Reduction in Mental and Physical Health: Is Mindful Breathing Key?

Mindful breathing constitutes a crucial component of Mindfulness-Based Stress Reduction (MBSR). This study aimed to compare the effects of MBSR training with and without mindful breathing components on physical and mental health, with the primary goal of clarifying the specific contribution and significance of mindful breathing within the MBSR regimen.

Forty-eight participants were randomly assigned to either the experimental (MBSR) or the control (MBSR without mindful breathing) group. The assessment consisted of two parts: analyzing the functional structure of inner core muscles via ultrasound, utilizing B-mode for muscle thickness, M-mode for diaphragmatic excursion, and shear wave elastography for muscle elasticity. Mental health assessments employed the Five Facet Mindfulness Questionnaire (FFMQ), the 21-item Depression Anxiety Stress Scales (DASS-21), and the Regulatory Self-Efficacy Scale (RESE).

After the intervention, the experimental group demonstrated a significant increase in diaphragmatic excursion and increased contracted state multifidus muscle thickness in contrast to the control group. Both groups exhibited improved mental health status compared to the pre-intervention period, with no substantial difference between the experimental and control groups.

Mindful breathing may play a crucial role in activating inner core muscles within MBSR practice, notably contributing to increased diaphragmatic excursion. However, it is not the central component in promoting mental health through this practice.

This study was preregistered with the Chinese Clinical Trial Registry (ChiCTR2300070457).