Variation in plasma cytokine concentration during a training season in elite kayakers.

BACKGROUND

The purpose of this study was to investigate the differences in cytokines levels in the peripheral blood of kayakers at different moments of training.

METHODS

The sample comprised 12 elite kayakers preparing for the Beijing Olympic Games. Blood samples were collected at different time points of the training season: baseline (t0-November) after 6 weeks of off-training and before the start of the training season; t1 (January) at week 11 after a period of high-volume training; t2 (April) at week 26 at the end of a period of high intensity training sessions; t3 (June) at week 31 after a competitive period.

RESULTS

Decreases in cytokine levels were found for IL-1β and IL-18 at t1. IL-1 then increased throughout the remaining training season while IL-18 leveled off towards the end of the season. IL-1ra showed an exponential increase at t2 before leveling-off in the last period of training. No significant changes were found for IL-6, IFN-γ and TNF-α. No differences were observed in the magnitude and pattern of cytokines changes across the training season between the elite female and male kayakers.

CONCLUSIONS

Increases in training volume were able to induce decreases in pro-inflammatory plasma cytokine coinciding with the reported increase in upper respiratory tract infections in the kayakers.