The effect of pre-competition training on biochemical indices and immune function of volleyball players.

Objective: Pre-competition sports training can have varying effects on an athlete's immune function, including causing reduced resistance. The aim of this study was to explore effects of pre-competition training on some biochemical indices and immunologic functions in top-level volleyball athletes to determine whether training should be modified for optimal health.

Methods: Biochemical indices (Hb, BUN, CK, LDH) and immunologic function (IgA, IgG, IgM, CD3(+), CD4(+), CD8(+)) were detected by semiautomatic biochemistry analyzer, light scattering photometer, or flow cytometry in sera from 24 top-level volleyball athletes and compared before and after pre-competition training.

Results: After training, the levels of Hb, IgA, IgG, IgM, and CD4(+) and the CD4(+)/CD8(+) ratio decreased significantly, while BUN, CK, LDH, and CD8(+) increased significantly (P < 0.05). Further, the decrease in Hb levels in female athletes was more significant than that in male athletes (P < 0.05).

Conclusions: These results indicate that pre-competition training affects biochemical indices and immunologic function in this group of athletes. Additionally, more dramatic changes in Hb in female athletes may indicate a need for adapted training loads and rest periods for females.