Real time biofeedback and athletic performance in competitive athletes

Background: Real-time physiological and biomechanical feedback may support athletic self-regulation, but the evidence combines markedly different technologies, performance tasks and methodological standards. Objective: To evaluate controlled biofeedback interventions in competitive athletes and distinguish direct performance effects from physiological proxies and multicomponent treatment effects. Methods: A retrospectively developed protocol defined competitive athletes internationally, contemporaneous feedback from measured signals, concurrent comparators and direct sport or validated motor-performance outcomes. PubMed and Europe PMC searches were executed on 9 October 2026. Search responses, eligibility records and calculation inputs were retained. Two reviewers independently screened records, assessed eligibility, extracted data and appraised the evidence; disagreements were resolved through discussion or adjudication by a third researcher. RoB 2 and ROBINS-I were applied according to design, with outcome-specific GRADE judgments. Independent group mean differences were recalculated with Welch 95% confidence intervals; standardized effects were plotted descriptively. Results: PubMed returned 476 identifiers and Europe PMC returned 484 records, yielding 531 database records after removal of 429 cross-source identifier duplicates. Forty-six database candidates and eleven supplied or citation-identified candidates formed 57 report packets sought; 33 were assessed and 24 were not obtained. Fifteen assessed reports met the operational criteria, with unresolved study linkage. Eight contrasts from seven reports could be recalculated. Putting error was −2.21 cm (95% CI −10.33 to 5.91), shooting accuracy 0.30 points (−0.04 to 0.64), batting score 1.40 points (−10.49 to 13.29), and reactive strength index 0.19 units (0.02 to 0.36). These are distinct comparisons, not components of one pooled estimate. Reporting contradictions, small samples and incomplete methods limited certainty. Conclusions: The assessed evidence does not establish a general performance benefit from real-time biofeedback. Some task-specific findings warrant further investigation, but certainty is low or very low. Incomplete search coverage, unavailable reports and possible cohort overlap limit the completeness and generalizability of the findings.