Cortisol level modulated by integrative meditation in a dose-dependent fashion

Prior research has shown that an additional training session immediately after acute stress decreases release of salivary cortisol in a college student group trained with 5-day integrative body-mind training (IBMT) in comparison with a control group given the same amount of relaxation training. However, 5 days of training does not influence the basal secretion of cortisol. The current study seeks to extend this finding and determine whether increasing amounts of IBMT will decrease the basal cortisol level, suggesting reduced stress to daily activities. Thirty-four Chinese undergraduates were randomly assigned either to 4 weeks of IBMT or a relaxation control. Salivary cortisol levels at baseline before training and the three stages of a stress intervention test (i.e. rest, stress and additional 20-min practice) after 2 and 4 weeks of training were assessed. The basal cortisol level decreased significantly in the IBMT but not in relaxation group after 2 and 4 weeks of training. An additional IBMT practice session immediately after acute stress produced significantly lower cortisol release for the IBMT group in comparison with relaxation at weeks 2 and 4. The results indicate that IBMT produces a change in the basal endocrine system and larger acute effects as the dose of training increases.