Effects of match play and training on circulating S100B concentration in professional rugby players.

Objectives: Examine the effects of match play and a season of training on serum S100B concentration in male professional rugby players. To assess the influence of contact play, values were compared with age- and fitness-matched athletes not involved in a contact sport.
Methods: Over a 2-year period, blood samples were collected from 38 players in pre-season, end of season, and post-matches (within 2 h). A control group of rowers (n = 15) was assessed pre- and post-training.
Results: S100B concentration changed significantly over a season (χ2(2) = 17.636, p < 0.0005); post-match values were significantly increased from baseline (early season: Z = -3.670, p < 0.0005; late season: Z = -3.408, p = 0.001). There were no significant differences in S100B concentrations between pre-seasons (Z = -1.601, p = 0.109), or between end of season and subsequent pre-season (Z = -0.330, p = 0.741). While comparable at baseline, samples taken from rugby players post-match were significantly increased compared with samples taken from rowers post-exercise (U = 47.0, p < 0.0005).
Conclusion: Exercise has a significant effect on circulating S100B in elite male athletes, with levels following rugby matches significantly higher than following non-contact sport. This elevation in S100B is temporary, with a return to baseline values after periods without play.