1 Department of Psychiatry, Oxford University, Oxford, UK kearnan.myall@kellogg.ox.ac.uk jesus.monteromarin@psych.ox.ac.uk.
2 Teaching, Reseach and Innovation Unit, Parc Sanitari Sant Joan de Déu, Sant Boi de Llobregat, Spain.
3 School of Human Science, University of Greenwich, London, UK.
4 Department of Psychiatry, Oxford University, Oxford, UK.
5 Oxford Health NHS Foundation Trust, NHS, Oxford, UK.
6 Department of Education, Concordia University, Montreal, Quebec, Canada.
7 Bodleian Health Care Libraries, Oxford University, Oxford, UK.

Objective: To determine the effectiveness of mindfulness-based programmes (MBPs) on the mental health of elite athletes.

Design: Systematic review and meta-analysis.

Data sources: Eight online databases (Embase, PsycINFO, SPORTDiscus, MEDLINE, Scopus, Cochrane CENTRAL, ProQuest Dissertations & Theses and Google Scholar), plus forward and backward searching from included studies and previous systematic reviews.

Eligibility criteria for selecting studies: Studies were included if they were randomised controlled trials (RCTs) that compared an MBP against a control, in current or former elite athletes.

Results: Of 2386 articles identified, 12 RCTs were included in this systematic review and meta-analysis, comprising a total of 614 elite athletes (314 MBPs and 300 controls). Overall, MBPs improved mental health, with large significant pooled effect sizes for reducing symptoms of anxiety (hedges g=-0.87, number of studies (n)=6, p=0.017, I ²=90) and stress (g=-0.91, n=5, p=0.012, I ²=74) and increasing psychological well-being (g=0.96, n=5, p=0.039., I ²=89). Overall, the risk of bias and certainty of evidence was moderate, and all findings were subject to high estimated levels of heterogeneity.

Conclusion: MBPs improved several mental health outcomes. Given the moderate degree of evidence, high-quality, adequately powered trials are required in the future. These studies should emphasise intervention fidelity, teacher competence and scalability within elite sport.

Prospero registration number: CRD42020176654.