Impact of Mango Puree Supplementation on Inflammatory, Muscle Damage, and Selected T-Cell Biomarkers in Elite Beach Volleyball Players During Regular Training

<b>Background/Objectives</b>: Mango is a tropical fruit rich in polyphenols and carotenoids that may support recovery-related physiological responses during athletic training. This study examined the effects of mango puree supplementation on inflammatory biomarkers, muscle damage, and selected T-cell subsets in Thai men's national beach volleyball players during regular training. <b>Methods</b>: Fifteen male athletes completed a pilot randomized, single-blind, crossover trial. Participants consumed the mango puree or placebo (600 g/day) for 4 weeks, separated by a 2-week washout period. Blood samples and physiological measurements were collected at baseline and at the end of each intervention period. Outcomes were analyzed using linear mixed-effects models. <b>Results</b>: Mango puree supplementation was associated with lower concentrations of C-reactive protein (mean difference: -1.6 mg/L; 95% CI: -2.1 to -1.1; <i>p</i> < 0.001), interleukin-6 (-0.7 pg/mL; 95% CI: -1.2 to -0.3; <i>p</i> = 0.003), and creatine kinase (-290.1 U/L; 95% CI: -356.1 to -224.1; <i>p</i> < 0.001) compared with the placebo. The percentage of CD4+ T cells (9.82 percentage points; 95% CI: 5.0 to 14.6; <i>p</i> < 0.001) and the CD4/CD8 ratio (0.37; 95% CI: 0.11 to 0.63; <i>p</i> = 0.007) were higher during mango puree supplementation, while CD8+ T-cell percentage did not differ between conditions. No significant treatment effects were observed for body composition parameters or blood pressure (all <i>p</i> > 0.05). Total energy intake remained unchanged across intervention periods (<i>p</i> > 0.05). <b>Conclusions</b>: Mango puree supplementation during regular training was associated with lower inflammatory and muscle damage biomarkers and alterations in selected T-cell subsets compared with the placebo.