Effects of summer training camp on serum opsonic activity and plasma cytokine levels in female long-distance runners.

In a summer training camp, strenuous physical exercises are carried out to improve endurance ability. The effects of the training stress on the immune system have been studied extensively. However, less attention has been paid to non-specific immunological changes. Serum opsonic activity (SOA) is a more direct and suitable indicator of non-specific humoral immunity. In this study, we used the luminal-dependent chemiluminescence (LmCL) to measure reactive oxygen species generation from pooled human neutrophils as an indicator of SOA. We also measured plasma myeloperoxidase (MPO) and plasma cytokine levels. Twenty-two female college runners took part in this study after giving their written informed consent. There was no significant difference in the physical characteristics and serum enzyme levels. However, significant differences were observed in the changes of blood property and plasma cytokine levels. According to MPO levels, neutrophils in vivo may be deactivated during the camp. Positive correlations between fluctuations of pro- and anti-inflammatory cytokine levels were observed in this study. According to the results of peak time and peak height of LmCL, SOA seems to increase at first qualitatively and then quantitatively during the summer camp. The increased SOA level may compensate for the decrease in neutrophil activity.