Placebo effects on the quantity and quality of relaxation training.

Many people find it difficult to practice progressive muscle relaxation (PMR) regularly. We attempted to improve relaxation quantity (i.e. adherence), and relaxation quality via placebo. A total of 100 women were randomly assigned to a standard group, which practiced PMR at home every day for two weeks, or a placebo group, which practiced PMR for two weeks with additional daily placebo treatment. To monitor adherence to relaxation practice, we used a smartphone app. The placebo group practiced more often than the standard group. Both groups did not differ in their reported relaxation level after the daily exercises.