The effect of tart cherry juice (TCJ) supplementation on exercise-induced muscle damage (EIMD) in an athletic population.

Introduction: This systematic review and meta-analysis quantified the effect of tart cherry juice (TCJ) supplementation on exercise-induced muscle damage (EIMD). Evidence supported TCJ's beneficial effects on muscular function and inflammatory biomarkers interleukin (IL)-6 and IL-8.

Method: PubMed, Scopus, and Web of Science were searched up to January 2024. Risk of bias was assessed using RevMan® software. Mean differences and 95% confidence intervals (CIs) of maximal voluntary isometric contraction (MVIC), inflammatory markers, creatine kinase (CK), and visual analog scale (VAS) score were pooled using fixed- or random-effect models. Heterogeneity was assessed using Chi-square or I ² statistics.

Results: Ten trials were included in the analysis. TCJ supplementation significantly improved MVIC [weighted mean difference (WMD) = 9.13%, 95% CI (6.42-11.84), I ² = 62.3%] and decreased IL-6 [WMD = -0.4 pg/ml, 95% CI (-0.68 to -0.11), I ² = 62.2%] and IL-8 [WMD = -0.3 pg/ml, 95% CI (-0.6 to -0.0), I ² = 46.3%]. No significant changes were found in CK, C-reactive protein, IL-1β, tumor necrosis factor-alpha, or VAS score. Dose-response analysis revealed a significant non-linear association between daily TCJ dose and MVIC effect size.

Conclusion: TCJ supplementation may improve muscle function and some inflammatory biomarkers in EIMD. Further high-quality studies with larger sample sizes are needed to determine TCJ's long-term effects.