Objective: This systematic review and multilevel meta-analysis aimed to quantify the effects of structured self-talk interventions on athletic performance and psychological functioning in athletes and to determine whether intervention, sport, and participant characteristics moderate these effects.

Methods: A systematic search of PubMed, Web of Science, Scopus, SPORTDiscus, and PsycINFO was conducted for studies published from January 2020 to January 2026. Eligible studies were randomized controlled trials and controlled experimental studies that examined structured self-talk interventions in athletic populations and reported at least one performance or psychological outcome. The primary outcome was athletic performance, whereas secondary outcomes included self-confidence, anxiety, motivation, perceived competence, attentional control, and other theoretically relevant psychological outcomes. Two independent reviewers conducted study selection, data extraction, and risk-of-bias assessment. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated using a random-effects framework. A multilevel meta-analytic model was employed to account for the statistical dependency of multiple effect sizes extracted from individual studies. Heterogeneity was evaluated using variance components and I² statistics, and moderator analyses examined self-talk type, intervention duration, sport type, competitive level, and participant characteristics.

Results: The systematic search identified 3,247 records, of which 68 studies met the eligibility criteria and 54 were included in the quantitative synthesis. The multilevel meta-analysis demonstrated a significant moderate positive effect of self-talk interventions on athletic performance (SMD=0.42, 95% CI [0.31, 0.53], P<0.001). Self-talk interventions also produced significant effects on selected psychological outcomes, including self-confidence (SMD=0.38, 95% CI [0.26, 0.50]), anxiety (SMD=−0.29, 95% CI [−0.41, −0.17]), and attentional control (SMD=0.34, 95% CI [0.22, 0.46]). Moderator analyses indicated that instructional self-talk produced significantly larger performance effects than motivational self-talk (p = 0.02). Longer interventions (≥4 weeks) and team-sport contexts were also associated with larger effects. Conclusions: These findings highlight the importance of matching self-talk strategies to the demands of the sport and the targeted psychological or performance outcome. Future research should employ theoretically grounded and standardized intervention protocols, adequately powered controlled designs, and longer follow-up periods, with particular attention to the generalizability and transfer of self-talk effects from controlled experimental tasks to ecologically valid competitive settings.