The goal of this randomized controlled trial was to test whether the placebo or nonspecific enhancement of well-being brought about by a health-promoting behaviour was a result of the response expectancy theory or the motivational concordance theory. A total of 57 participants completed a breathing exercise – the Buteyko Method over a 4-day period. The results remained consistent with the hypothesis that placebo effects in therapeutic contexts are mediated through the affective consequences of performing a motivated ritual. Sierra, C, Hyland, M. (2011) Health Psychol. Volume 30, Issue 6, pp. 793-796. Read the Study