Effectiveness of an online Acceptance and Commitment Therapy-based sport psychology programme for managing trait perfectionism, perfectionistic thoughts, and emotions in athletes.

Perfectionism is related to a number of problems for athletes that include performance and wellbeing difficulties. Some of these problems are due to their trait perfectionism and others due to the experience of perfectionistic cognitions - automatic ruminative thoughts and images about the need to be perfect. A small number of studies have examined the effectiveness of different types of interventions to help reduce trait perfectionism, perfectionistic cognitions, and related problems in athletes. The current study builds on existing research by assessing the effectiveness of a novel online Acceptance and Commitment Therapy (ACT)-based programme to do the same.