The effectiveness of mindfulness therapy on psychological flexibility and sports self-efficacy in adolescent female volleyball players in Tonekabon city.

The present study was conducted to determine the effectiveness of mindfulness therapy on psychological flexibility and sports self-efficacy in adolescent female volleyball players in Tonekabon city. The present study was a semi-experimental study with a pre-test-post-test design with a control group. The statistical population of the study included all adolescent female volleyball players in Tonekabon city in 1404. 30 people from the statistical population were selected by purposive sampling method and randomly assigned to two experimental and control groups (15 people in each group). The experimental group received 8 90-minute mindfulness therapy sessions. The research tools included the Ben Itzhak, Blevstein, and Moore (2014) Psychological Flexibility Questionnaire and the Kerl et al. (2007) Sports Self-Efficacy Scale. The results of the multivariate analysis of covariance test showed that there was a significant difference at the 0.01 level between the mean of psychological flexibility and sports self-efficacy in the experimental and control groups. The results showed that mindfulness therapy is an effective method for improving psychological flexibility and sports self-efficacy.