Effects of cholecalciferol supplementation on inflammatory markers and muscle damage indices of soccer players after a simulated soccer match

Abstract Objectives Soccer-induced muscle damage and inflammation lead to a reduction in athletic performance. The aim of this study was to determine whether supplementation with cholecalciferol would reduce inflammation and muscle damage in soccer players after a simulated soccer match. Methods Twenty-two soccer players (median age 27 y, interquartile range 5 y) were divided randomly into two groups, as follows: a cholecalciferol group (n = 11) and a placebo group (n = 11). Cholecalciferol supplements (50 000 IU/wk) or placebos were administered to the groups by an independent co-worker. After 8 wk, the athletes participated in a simulated soccer match, and perceived exertion and heart rates were measured during the trial. Blood samples were obtained presupplementation, postsupplementation, immediately after, and 2- and 24-h postexercise for measurement of lactate dehydrogenase, creatine phosphokinase, C-reactive protein (CRP), and interleukin (IL)-6. Results The intervention group demonstrated a significant increase in serum 25-hydroxyvitamin D levels (53.93, 10.68 ng/mL , P P ˃ 0.05) but showed increased IL-6 ( P  = 0.034). In addition, the ratings of perceived exertion and heart rates were not altered by vitamin D compared with placebo ingestion ( P  = 0.155 versus P  = 0.261; P  = 0.600 versus P  = 0.983). Conclusion The study showed that 50 000 IU/wk of cholecalciferol supplementation for 8 wk increased the 25-hydroxyvitamin D levels, with no effect on muscle damage indices or CRP. However, The IL-6 concentration was generally higher in the intervention group.