Effect of Physical Fitness and Endurance Exercise on Indirect Biomarkers of Recombinant Erythropoietin Misuse - Abellan, R; Ventura, R; Pichini, S; Palmi, I; Bellver, M; Olive, R; Pacifici, R; Pascual, J A; Zuccaro, P; Segura, J (International Journal of Sports Medicine, 2007)