Decreased mean sphered cell volume values in top-level rugby players are related to the intravascular hemolysis induced by exercise

Sports anemia is a common risk for athletes. Intravasclar hemolysis is the principal source of an accelerated turnover of erythrocytes in sportsmen. The hemolysis induces some biochemical and hematological modifications; in particular, high concentrations of total and indirect (unconjugated) bilirubin could be reported in professional athletes. We recruited 24 rugby players of the Italian National Team. In these athletes we measured hematological parameters, including mean sphered cell volume (MSCV) by means of Coulter LH 750 (Beckman Coulter, Brea, CA, USA), beside biochemical parameters, including bilirubin and haptoglobin. We observed differences in the athletes' indirect bilirubin between the blood drawing performed before the start of training and competitions and the one performed at the end of the competition season. The bilirubin was increased during competition season from 7% to 329% when compared with the baseline value measured before training and competitions. MSCV, in contrast, decreased from a mean of 88.4 fL to 86 fL. The MSCV decrease in association with an indirect bilirubin increase is a specific sign of erythrocyte destruction, and specific training and competitions schemes and diet or therapy modifications should be decided according to their values. The modifications of MSCV are correlated with those of haptoglobin and hemoglobin, but not with reticulocytosis.