[Efficacy of the controlled breathing therapy on stress: biological correlates. preliminary study]

The objective was to compare the efficacy of a psychophysiological intervention, "voluntary management breathing control therapy", with psychological information about stress in a placebo-controlled trial. 50 subjects recruited from a university course for people over 55 participated in the study Levels of morning and night salivary cortisol before and after treatment were evaluated. After 4 weeks the difference in cortisol decrease between voluntary breathing therapy and psychological information about stress and placebo condition was not significant although the group of voluntary breathing therapy showed a decrease in cortisol with an important effect size. Decreases in cortisol differed between men and women. Even the small number of sessions, the voluntary control therapy showed an effect over the cortisol, which diminished. This should be tested in different populations and with a longer number of sessions.