PTSD symptom reduction with mindfulness-based stretching and deep breathing exercise: randomized controlled clinical trial of efficacy

J Clin Endocrinol Metab. 2013 Jul;98(7):2984-92. doi: 10.1210/jc.2012-3742. Epub 2013 May 29.


Context: Abnormal cortisol levels are a key pathophysiological indicator of post-traumatic stress disorder (PTSD). Endogenous normalization of cortisol concentration through exercise may be associated with PTSD symptom reduction.

Objective: The aim of the study was to determine whether mindfulness-based stretching and deep breathing exercise (MBX) normalizes cortisol levels and reduces PTSD symptom severity among individuals with subclinical features of PTSD.

Design and setting: A randomized controlled trial was conducted at the University of New Mexico Health Sciences Center.

Participants: Twenty-nine nurses (28 female) aged 45-66 years participated in the study.

Intervention: Sixty-minute MBX sessions were conducted semiweekly for 8 weeks.

Main outcome measures: Serum cortisol was measured, and the PTSD Checklist-Civilian version (PCL-C) was performed at baseline and weeks 4, 8, and 16.

Results: Twenty-nine participants completed the study procedures, 22 (79%) with PTSD symptoms (MBX, n = 11; control, n = 11), and 7 (21%) without PTSD (BASE group). Eight-week outcomes for the MBX group were superior to those for the control group (mean difference for PCL-C scores, -13.6; 95% confidence interval [CI], -25.6, -1.6; P = .01; mean difference for serum cortisol, 5.8; 95% CI, 0.83, 10.8; P = .01). No significant differences were identified between groups in any other items. The changes in the MBX group were maintained at the 16-week follow-up (P = .85 for PCL-C; P = .21 for cortisol). Our data show that improved PTSD scores were associated with normalization of cortisol levels (P < .05).

Conclusions: The results suggest that MBX appears to reduce the prevalence of PTSD-like symptoms in individuals exhibiting subclinical features of PTSD.

Trial registration: NCT01462045.

Publication types

  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural

MeSH terms

  • Academic Medical Centers
  • Adrenocorticotropic Hormone / blood
  • Adrenocorticotropic Hormone / metabolism
  • Aged
  • Breathing Exercises*
  • Dehydroepiandrosterone Sulfate / blood
  • Down-Regulation*
  • Female
  • Follow-Up Studies
  • Humans
  • Hydrocortisone / blood*
  • Hydrocortisone / metabolism
  • Male
  • Middle Aged
  • Muscle Stretching Exercises*
  • Neurosecretory Systems / physiopathology*
  • New Mexico
  • Nurses
  • Psychiatric Status Rating Scales
  • Psychophysiology
  • Severity of Illness Index
  • Stress Disorders, Post-Traumatic / blood
  • Stress Disorders, Post-Traumatic / physiopathology
  • Stress Disorders, Post-Traumatic / psychology
  • Stress Disorders, Post-Traumatic / therapy*


  • Dehydroepiandrosterone Sulfate
  • Adrenocorticotropic Hormone
  • Hydrocortisone

Associated data